diff --git a/.rubocop.yml b/.rubocop.yml
index 8074b24a..a5b51f7b 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,7 +1,4 @@
 inherit_from: .rubocop_todo.yml
 
-Metrics/LineLength:
-  Max: 120
-
 Style/StringLiterals:
   Enabled: false
diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index d150c54d..ce6105cc 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -1,132 +1,25 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2020-09-09 23:09:21 UTC using RuboCop version 0.90.0.
+# on 2020-09-18 20:20:54 UTC using RuboCop version 0.91.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.
 
 # Offense count: 1
-# Cop supports --auto-correct.
-Layout/BlockEndNewline:
-  Exclude:
-    - 'spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-Layout/ClosingParenthesisIndentation:
-  Exclude:
-    - 'examples/helpers/eventwebhook/example.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-Layout/EmptyLineAfterGuardClause:
-  Exclude:
-    - 'lib/rack/sendgrid_webhook_verification.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-Layout/EmptyLineAfterMagicComment:
-  Exclude:
-    - 'test/sendgrid/helpers/mail/test_attachment.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: empty_lines, empty_lines_except_namespace, empty_lines_special, no_empty_lines, beginning_only, ending_only
-Layout/EmptyLinesAroundClassBody:
-  Exclude:
-    - 'test/sendgrid/permissions/test_scopes.rb'
-
-# Offense count: 7
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, IndentationWidth.
-# SupportedStyles: consistent, consistent_relative_to_receiver, special_for_inner_method_call, special_for_inner_method_call_in_parentheses
-Layout/FirstArgumentIndentation:
-  Exclude:
-    - 'examples/helpers/eventwebhook/example.rb'
-    - 'spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, IndentationWidth.
-# SupportedStyles: special_inside_parentheses, consistent, align_braces
-Layout/FirstHashElementIndentation:
-  Exclude:
-    - 'spec/fixtures/event_webhook.rb'
-
-# Offense count: 3
-# Cop supports --auto-correct.
-# Configuration parameters: AllowMultipleStyles, EnforcedHashRocketStyle, EnforcedColonStyle, EnforcedLastArgumentHashStyle.
-# SupportedHashRocketStyles: key, separator, table
-# SupportedColonStyles: key, separator, table
-# SupportedLastArgumentHashStyles: always_inspect, always_ignore, ignore_implicit, ignore_explicit
-Layout/HashAlignment:
-  Exclude:
-    - 'spec/fixtures/event_webhook.rb'
-
-# Offense count: 27
-# Cop supports --auto-correct.
-# Configuration parameters: AutoCorrect, AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
-# URISchemes: http, https
-Layout/LineLength:
-  Max: 381
-
-# Offense count: 1
-# Cop supports --auto-correct.
-Layout/MultilineBlockLayout:
-  Exclude:
-    - 'spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb'
-
-# Offense count: 3
-# Cop supports --auto-correct.
-# Configuration parameters: AllowForAlignment, EnforcedStyleForExponentOperator.
-# SupportedStylesForExponentOperator: space, no_space
-Layout/SpaceAroundOperators:
-  Exclude:
-    - 'spec/fixtures/event_webhook.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyleForEmptyBraces.
-# SupportedStyles: space, no_space
-# SupportedStylesForEmptyBraces: space, no_space
-Layout/SpaceBeforeBlockBraces:
-  EnforcedStyle: space
-
-# Offense count: 3
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, EnforcedStyleForEmptyBraces, SpaceBeforeBlockParameters.
-# SupportedStyles: space, no_space
-# SupportedStylesForEmptyBraces: space, no_space
-Layout/SpaceInsideBlockBraces:
+# Configuration parameters: Include.
+# Include: **/*.gemspec
+Gemspec/RequiredRubyVersion:
   Exclude:
-    - 'examples/ips/ips.rb'
-    - 'lib/sendgrid/helpers/ip_management/ip_management.rb'
+    - 'sendgrid-ruby.gemspec'
 
-# Offense count: 8
-# Cop supports --auto-correct.
-# Configuration parameters: AllowInHeredoc.
-Layout/TrailingWhitespace:
-  Exclude:
-    - 'examples/helpers/mail/example.rb'
-    - 'examples/mail/mail.rb'
-    - 'lib/sendgrid/helpers/permissions/scope.rb'
-    - 'spec/fixtures/event_webhook.rb'
-    - 'spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb'
-    - 'test/sendgrid/helpers/mail/test_attachment.rb'
-
-# Offense count: 2
-Lint/ImplicitStringConcatenation:
-  Exclude:
-    - 'test/sendgrid/helpers/mail/test_attachment.rb'
-
-# Offense count: 16
+# Offense count: 22
 Lint/UselessAssignment:
   Exclude:
+    - 'examples/scopes/scopes.rb'
     - 'spec/rack/sendgrid_webhook_verification_spec.rb'
 
-# Offense count: 4
+# Offense count: 8
 # Configuration parameters: IgnoredMethods.
 Metrics/AbcSize:
   Max: 144
@@ -137,22 +30,22 @@ Metrics/AbcSize:
 Metrics/BlockLength:
   Max: 96
 
-# Offense count: 1
+# Offense count: 3
 # Configuration parameters: CountComments, CountAsOne.
 Metrics/ClassLength:
-  Max: 123
+  Max: 2006
 
-# Offense count: 14
+# Offense count: 41
 # Configuration parameters: CountComments, CountAsOne, ExcludedMethods.
 Metrics/MethodLength:
-  Max: 83
+  Max: 141
 
-# Offense count: 1
+# Offense count: 2
 # Configuration parameters: CountKeywordArgs.
 Metrics/ParameterLists:
-  Max: 6
+  Max: 7
 
-# Offense count: 3
+# Offense count: 4
 # Configuration parameters: ExpectMatchingDefinition, CheckDefinitionPathHierarchy, Regex, IgnoreExecutableScripts, AllowedAcronyms.
 # AllowedAcronyms: CLI, DSL, ACL, API, ASCII, CPU, CSS, DNS, EOF, GUID, HTML, HTTP, HTTPS, ID, IP, JSON, LHS, QPS, RAM, RHS, RPC, SLA, SMTP, SQL, SSH, TCP, TLS, TTL, UDP, UI, UID, UUID, URI, URL, UTF8, VM, XML, XMPP, XSRF, XSS
 Naming/FileName:
@@ -160,6 +53,14 @@ Naming/FileName:
     - 'gemfiles/Sinatra_1.gemfile'
     - 'gemfiles/Sinatra_2.gemfile'
     - 'lib/sendgrid-ruby.rb'
+    - 'test/sendgrid/test_sendgrid-ruby.rb'
+
+# Offense count: 1
+# Configuration parameters: MinNameLength, AllowNamesEndingInNumbers, AllowedNames, ForbiddenNames.
+# AllowedNames: at, by, db, id, in, io, ip, of, on, os, pp, to
+Naming/MethodParameterName:
+  Exclude:
+    - 'lib/sendgrid/helpers/mail/personalization.rb'
 
 # Offense count: 1
 # Configuration parameters: NamePrefix, ForbiddenPrefixes, AllowedMethods, MethodDefinitionMacros.
@@ -172,50 +73,9 @@ Naming/PredicateName:
     - 'spec/**/*'
     - 'examples/helpers/eventwebhook/example.rb'
 
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, ProceduralMethods, FunctionalMethods, IgnoredMethods, AllowBracesOnProceduralOneLiners, BracesRequiredMethods.
-# SupportedStyles: line_count_based, semantic, braces_for_chaining, always_braces
-# ProceduralMethods: benchmark, bm, bmbm, create, each_with_object, measure, new, realtime, tap, with_object
-# FunctionalMethods: let, let!, subject, watch
-# IgnoredMethods: lambda, proc, it
-Style/BlockDelimiters:
-  Exclude:
-    - 'spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb'
-
-# Offense count: 14
+# Offense count: 35
 Style/Documentation:
-  Exclude:
-    - 'spec/**/*'
-    - 'test/**/*'
-    - 'lib/sendgrid/helpers/inbound/app.rb'
-    - 'lib/sendgrid/helpers/ip_management/ip_management.rb'
-    - 'lib/sendgrid/helpers/mail/category.rb'
-    - 'lib/sendgrid/helpers/permissions/scope.rb'
-    - 'lib/sendgrid/helpers/settings/mail_settings_dto.rb'
-    - 'lib/sendgrid/helpers/settings/partner_settings_dto.rb'
-    - 'lib/sendgrid/helpers/settings/settings.rb'
-    - 'lib/sendgrid/helpers/settings/tracking_settings_dto.rb'
-    - 'lib/sendgrid/helpers/settings/user_settings_dto.rb'
-    - 'lib/sendgrid/helpers/stats/email_stats.rb'
-    - 'lib/sendgrid/helpers/stats/metrics.rb'
-    - 'lib/sendgrid/helpers/stats/stats_response.rb'
-    - 'lib/sendgrid/sendgrid.rb'
-    - 'lib/sendgrid/twilio_email.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: compact, expanded
-Style/EmptyMethod:
-  Exclude:
-    - 'test/sendgrid/helpers/mail/test_attachment.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-Style/Encoding:
-  Exclude:
-    - 'test/sendgrid/helpers/mail/test_attachment.rb'
+  Enabled: false
 
 # Offense count: 4
 # Configuration parameters: EnforcedStyle.
@@ -224,34 +84,14 @@ Style/FormatStringToken:
   Exclude:
     - 'examples/emailactivity/emailactivity.rb'
 
-# Offense count: 72
+# Offense count: 97
 # Cop supports --auto-correct.
 # Configuration parameters: EnforcedStyle.
 # SupportedStyles: always, always_true, never
 Style/FrozenStringLiteralComment:
   Enabled: false
 
-# Offense count: 2
-# Configuration parameters: MinBodyLength.
-Style/GuardClause:
-  Exclude:
-    - 'lib/rack/sendgrid_webhook_verification.rb'
-    - 'lib/sendgrid/helpers/eventwebhook/eventwebhook.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-Style/IfUnlessModifier:
-  Exclude:
-    - 'lib/sendgrid/helpers/eventwebhook/eventwebhook.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: IgnoredMethods.
-Style/MethodCallWithoutArgsParentheses:
-  Exclude:
-    - 'examples/emailactivity/emailactivity.rb'
-
-# Offense count: 5
+# Offense count: 6
 Style/MixinUsage:
   Exclude:
     - 'examples/helpers/eventwebhook/example.rb'
@@ -259,63 +99,11 @@ Style/MixinUsage:
     - 'examples/helpers/settings/example.rb'
     - 'examples/helpers/stats/example.rb'
     - 'test/sendgrid/helpers/mail/test_attachment.rb'
+    - 'test/sendgrid/helpers/mail/test_mail.rb'
 
-# Offense count: 7
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: literals, strict
-Style/MutableConstant:
-  Exclude:
-    - 'lib/sendgrid/helpers/eventwebhook/eventwebhook.rb'
-    - 'spec/fixtures/event_webhook.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-Style/OrAssignment:
-  Exclude:
-    - 'lib/sendgrid/sendgrid.rb'
-    - 'lib/sendgrid/twilio_email.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-Style/RedundantCondition:
-  Exclude:
-    - 'lib/sendgrid/base_interface.rb'
-
-# Offense count: 2
-# Cop supports --auto-correct.
-# Configuration parameters: AllowMultipleReturnValues.
-Style/RedundantReturn:
-  Exclude:
-    - 'lib/rack/sendgrid_webhook_verification.rb'
-
-# Offense count: 6
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, AllowInnerSlashes.
-# SupportedStyles: slashes, percent_r, mixed
-Style/RegexpLiteral:
-  Exclude:
-    - 'spec/rack/sendgrid_webhook_verification_spec.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle.
-# SupportedStyles: implicit, explicit
-Style/RescueStandardError:
-  Exclude:
-    - 'lib/sendgrid/helpers/eventwebhook/eventwebhook.rb'
-
-# Offense count: 1
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyleForMultiline.
-# SupportedStylesForMultiline: comma, consistent_comma, no_comma
-Style/TrailingCommaInHashLiteral:
-  Exclude:
-    - 'spec/fixtures/event_webhook.rb'
-
-# Offense count: 27
+# Offense count: 55
 # Cop supports --auto-correct.
 # Configuration parameters: AutoCorrect, AllowHeredoc, AllowURI, URISchemes, IgnoreCopDirectives, IgnoredPatterns.
 # URISchemes: http, https
 Layout/LineLength:
-  Max: 381
+  Max: 3211
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9ff18474..100569cd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -171,7 +171,7 @@ All notable changes to this project will be documented in this file.
 
 ## [5.2.0] - 2017-10-30 ##
 ### Added
-- PR #234: Helpers for email statistics - global, category, subuser 
+- PR #234: Helpers for email statistics - global, category, subuser
 - Thanks to [Awin Abi](https://github.com/awinabi) for the pull request!
 
 ## [5.1.0] - 2017-9-1 ##
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index f54e47e8..10508b2d 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -149,10 +149,10 @@ Please run your code through:
    ```bash
    # Clone your fork of the repo into the current directory
    git clone https://github.com/sendgrid/sendgrid-ruby
-   
+
    # Navigate to the newly cloned directory
    cd sendgrid-ruby
-   
+
    # Assign the original repo to a remote called "upstream"
    git remote add upstream https://github.com/sendgrid/sendgrid-ruby
    ```
diff --git a/Makefile b/Makefile
index c35f356a..faee8997 100644
--- a/Makefile
+++ b/Makefile
@@ -5,6 +5,7 @@ install:
 
 test:
 	bundle exec rake
+	rubocop
 
 test-integ: test
 
diff --git a/README.md b/README.md
index de51c4ab..32bb603f 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 ![Twilio SendGrid Logo](twilio_sendgrid_logo.png)
 
-[![Travis Badge](https://travis-ci.org/sendgrid/sendgrid-ruby.svg?branch=main)](https://travis-ci.org/sendgrid/sendgrid-ruby) 
+[![Travis Badge](https://travis-ci.org/sendgrid/sendgrid-ruby.svg?branch=main)](https://travis-ci.org/sendgrid/sendgrid-ruby)
 [![Gem Version](https://badge.fury.io/rb/sendgrid-ruby.svg)](https://badge.fury.io/rb/sendgrid-ruby)
 [![Email Notifications Badge](https://dx.sendgrid.com/badge/ruby)](https://dx.sendgrid.com/newsletter/ruby)
 [![MIT licensed](https://img.shields.io/badge/license-MIT-blue.svg)](./LICENSE.md)
diff --git a/Rakefile b/Rakefile
index ad77bbfa..f94bea21 100644
--- a/Rakefile
+++ b/Rakefile
@@ -10,5 +10,5 @@ end
 
 RSpec::Core::RakeTask.new(:spec)
 
-desc "Run tests"
+desc 'Run tests'
 task default: %i[spec test]
diff --git a/examples/accesssettings/accesssettings.rb b/examples/accesssettings/accesssettings.rb
index caab8a17..90796bd6 100644
--- a/examples/accesssettings/accesssettings.rb
+++ b/examples/accesssettings/accesssettings.rb
@@ -63,7 +63,7 @@
 # Retrieve a specific whitelisted IP #
 # GET /access_settings/whitelist/{rule_id} #
 
-rule_id = "test_url_param"
+rule_id = 'test_url_param'
 response = sg.client.access_settings.whitelist._(rule_id).get
 puts response.status_code
 puts response.body
@@ -73,7 +73,7 @@
 # Remove a specific IP from the whitelist #
 # DELETE /access_settings/whitelist/{rule_id} #
 
-rule_id = "test_url_param"
+rule_id = 'test_url_param'
 response = sg.client.access_settings.whitelist._(rule_id).delete
 puts response.status_code
 puts response.body
diff --git a/examples/alerts/alerts.rb b/examples/alerts/alerts.rb
index 81128508..365b4873 100644
--- a/examples/alerts/alerts.rb
+++ b/examples/alerts/alerts.rb
@@ -32,7 +32,7 @@
 data = JSON.parse('{
   "email_to": "example@example.com"
 }')
-alert_id = "test_url_param"
+alert_id = 'test_url_param'
 response = sg.client.alerts._(alert_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -42,7 +42,7 @@
 # Retrieve a specific alert #
 # GET /alerts/{alert_id} #
 
-alert_id = "test_url_param"
+alert_id = 'test_url_param'
 response = sg.client.alerts._(alert_id).get
 puts response.status_code
 puts response.body
@@ -52,7 +52,7 @@
 # Delete an alert #
 # DELETE /alerts/{alert_id} #
 
-alert_id = "test_url_param"
+alert_id = 'test_url_param'
 response = sg.client.alerts._(alert_id).delete
 puts response.status_code
 puts response.body
diff --git a/examples/apikeys/apikeys.rb b/examples/apikeys/apikeys.rb
index 575207c5..a709ec97 100644
--- a/examples/apikeys/apikeys.rb
+++ b/examples/apikeys/apikeys.rb
@@ -41,7 +41,7 @@
     "user.profile.update"
   ]
 }')
-api_key_id = "test_url_param"
+api_key_id = 'test_url_param'
 response = sg.client.api_keys._(api_key_id).put(request_body: data)
 puts response.status_code
 puts response.body
@@ -54,7 +54,7 @@
 data = JSON.parse('{
   "name": "A New Hope"
 }')
-api_key_id = "test_url_param"
+api_key_id = 'test_url_param'
 response = sg.client.api_keys._(api_key_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -64,7 +64,7 @@
 # Retrieve an existing API Key #
 # GET /api_keys/{api_key_id} #
 
-api_key_id = "test_url_param"
+api_key_id = 'test_url_param'
 response = sg.client.api_keys._(api_key_id).get
 puts response.status_code
 puts response.body
@@ -74,7 +74,7 @@
 # Delete API keys #
 # DELETE /api_keys/{api_key_id} #
 
-api_key_id = "test_url_param"
+api_key_id = 'test_url_param'
 response = sg.client.api_keys._(api_key_id).delete
 puts response.status_code
 puts response.body
diff --git a/examples/asm/asm.rb b/examples/asm/asm.rb
index 42023f99..dc4a5be1 100644
--- a/examples/asm/asm.rb
+++ b/examples/asm/asm.rb
@@ -35,7 +35,7 @@
   "id": 103,
   "name": "Item Suggestions"
 }')
-group_id = "test_url_param"
+group_id = 'test_url_param'
 response = sg.client.asm.groups._(group_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -45,7 +45,7 @@
 # Get information on a single suppression group. #
 # GET /asm/groups/{group_id} #
 
-group_id = "test_url_param"
+group_id = 'test_url_param'
 response = sg.client.asm.groups._(group_id).get
 puts response.status_code
 puts response.body
@@ -55,7 +55,7 @@
 # Delete a suppression group. #
 # DELETE /asm/groups/{group_id} #
 
-group_id = "test_url_param"
+group_id = 'test_url_param'
 response = sg.client.asm.groups._(group_id).delete
 puts response.status_code
 puts response.body
@@ -71,7 +71,7 @@
     "test2@example.com"
   ]
 }')
-group_id = "test_url_param"
+group_id = 'test_url_param'
 response = sg.client.asm.groups._(group_id).suppressions.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -81,7 +81,7 @@
 # Retrieve all suppressions for a suppression group #
 # GET /asm/groups/{group_id}/suppressions #
 
-group_id = "test_url_param"
+group_id = 'test_url_param'
 response = sg.client.asm.groups._(group_id).suppressions.get
 puts response.status_code
 puts response.body
@@ -98,7 +98,7 @@
     "doesnotexists@example.com"
   ]
 }')
-group_id = "test_url_param"
+group_id = 'test_url_param'
 response = sg.client.asm.groups._(group_id).suppressions.search.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -108,8 +108,8 @@
 # Delete a suppression from a suppression group #
 # DELETE /asm/groups/{group_id}/suppressions/{email} #
 
-group_id = "test_url_param"
-email = "test_url_param"
+group_id = 'test_url_param'
+email = 'test_url_param'
 response = sg.client.asm.groups._(group_id).suppressions._(email).delete
 puts response.status_code
 puts response.body
@@ -143,7 +143,7 @@
 # Retrieve a Global Suppression #
 # GET /asm/suppressions/global/{email} #
 
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.asm.suppressions.global._(email).get
 puts response.status_code
 puts response.body
@@ -153,7 +153,7 @@
 # Delete a Global Suppression #
 # DELETE /asm/suppressions/global/{email} #
 
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.asm.suppressions.global._(email).delete
 puts response.status_code
 puts response.body
@@ -163,7 +163,7 @@
 # Retrieve all suppression groups for an email address #
 # GET /asm/suppressions/{email} #
 
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.asm.suppressions._(email).get
 puts response.status_code
 puts response.body
diff --git a/examples/campaigns/campaigns.rb b/examples/campaigns/campaigns.rb
index a4c532fd..c0cba430 100644
--- a/examples/campaigns/campaigns.rb
+++ b/examples/campaigns/campaigns.rb
@@ -54,7 +54,7 @@
   "subject": "New Products for Summer!",
   "title": "May Newsletter"
 }')
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -64,7 +64,7 @@
 # Retrieve a single campaign #
 # GET /campaigns/{campaign_id} #
 
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).get
 puts response.status_code
 puts response.body
@@ -74,7 +74,7 @@
 # Delete a Campaign #
 # DELETE /campaigns/{campaign_id} #
 
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).delete
 puts response.status_code
 puts response.body
@@ -87,7 +87,7 @@
 data = JSON.parse('{
   "send_at": 1489451436
 }')
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).schedules.patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -100,7 +100,7 @@
 data = JSON.parse('{
   "send_at": 1489771528
 }')
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).schedules.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -110,7 +110,7 @@
 # View Scheduled Time of a Campaign #
 # GET /campaigns/{campaign_id}/schedules #
 
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).schedules.get
 puts response.status_code
 puts response.body
@@ -120,7 +120,7 @@
 # Unschedule a Scheduled Campaign #
 # DELETE /campaigns/{campaign_id}/schedules #
 
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).schedules.delete
 puts response.status_code
 puts response.body
@@ -130,7 +130,7 @@
 # Send a Campaign #
 # POST /campaigns/{campaign_id}/schedules/now #
 
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).schedules.now.post
 puts response.status_code
 puts response.body
@@ -143,7 +143,7 @@
 data = JSON.parse('{
   "to": "your.email@example.com"
 }')
-campaign_id = "test_url_param"
+campaign_id = 'test_url_param'
 response = sg.client.campaigns._(campaign_id).schedules.test.post(request_body: data)
 puts response.status_code
 puts response.body
diff --git a/examples/clients/clients.rb b/examples/clients/clients.rb
index 62990f20..23f261a1 100644
--- a/examples/clients/clients.rb
+++ b/examples/clients/clients.rb
@@ -17,7 +17,7 @@
 # GET /clients/{client_type}/stats #
 
 params = JSON.parse('{"aggregated_by": "day", "start_date": "2016-01-01", "end_date": "2016-04-01"}')
-client_type = "test_url_param"
+client_type = 'test_url_param'
 response = sg.client.clients._(client_type).stats.get(query_params: params)
 puts response.status_code
 puts response.body
diff --git a/examples/contactdb/contactdb.rb b/examples/contactdb/contactdb.rb
index 0fdc69a2..04ce3e53 100644
--- a/examples/contactdb/contactdb.rb
+++ b/examples/contactdb/contactdb.rb
@@ -28,7 +28,7 @@
 # Retrieve a Custom Field #
 # GET /contactdb/custom_fields/{custom_field_id} #
 
-custom_field_id = "test_url_param"
+custom_field_id = 'test_url_param'
 response = sg.client.contactdb.custom_fields._(custom_field_id).get
 puts response.status_code
 puts response.body
@@ -38,7 +38,7 @@
 # Delete a Custom Field #
 # DELETE /contactdb/custom_fields/{custom_field_id} #
 
-custom_field_id = "test_url_param"
+custom_field_id = 'test_url_param'
 response = sg.client.contactdb.custom_fields._(custom_field_id).delete
 puts response.status_code
 puts response.body
@@ -88,7 +88,7 @@
   "name": "newlistname"
 }')
 params = JSON.parse('{"list_id": 1}')
-list_id = "test_url_param"
+list_id = 'test_url_param'
 response = sg.client.contactdb.lists._(list_id).patch(request_body: data, query_params: params)
 puts response.status_code
 puts response.body
@@ -99,7 +99,7 @@
 # GET /contactdb/lists/{list_id} #
 
 params = JSON.parse('{"list_id": 1}')
-list_id = "test_url_param"
+list_id = 'test_url_param'
 response = sg.client.contactdb.lists._(list_id).get(query_params: params)
 puts response.status_code
 puts response.body
@@ -110,7 +110,7 @@
 # DELETE /contactdb/lists/{list_id} #
 
 params = JSON.parse('{"delete_contacts": "true"}')
-list_id = "test_url_param"
+list_id = 'test_url_param'
 response = sg.client.contactdb.lists._(list_id).delete(query_params: params)
 puts response.status_code
 puts response.body
@@ -124,7 +124,7 @@
   "recipient_id1",
   "recipient_id2"
 ]')
-list_id = "test_url_param"
+list_id = 'test_url_param'
 response = sg.client.contactdb.lists._(list_id).recipients.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -135,7 +135,7 @@
 # GET /contactdb/lists/{list_id}/recipients #
 
 params = JSON.parse('{"page": 1, "page_size": 1, "list_id": 1}')
-list_id = "test_url_param"
+list_id = 'test_url_param'
 response = sg.client.contactdb.lists._(list_id).recipients.get(query_params: params)
 puts response.status_code
 puts response.body
@@ -145,8 +145,8 @@
 # Add a Single Recipient to a List #
 # POST /contactdb/lists/{list_id}/recipients/{recipient_id} #
 
-list_id = "test_url_param"
-recipient_id = "test_url_param"
+list_id = 'test_url_param'
+recipient_id = 'test_url_param'
 response = sg.client.contactdb.lists._(list_id).recipients._(recipient_id).post
 puts response.status_code
 puts response.body
@@ -157,8 +157,8 @@
 # DELETE /contactdb/lists/{list_id}/recipients/{recipient_id} #
 
 params = JSON.parse('{"recipient_id": 1, "list_id": 1}')
-list_id = "test_url_param"
-recipient_id = "test_url_param"
+list_id = 'test_url_param'
+recipient_id = 'test_url_param'
 response = sg.client.contactdb.lists._(list_id).recipients._(recipient_id).delete(query_params: params)
 puts response.status_code
 puts response.body
@@ -258,7 +258,7 @@
 # Retrieve a single recipient #
 # GET /contactdb/recipients/{recipient_id} #
 
-recipient_id = "test_url_param"
+recipient_id = 'test_url_param'
 response = sg.client.contactdb.recipients._(recipient_id).get
 puts response.status_code
 puts response.body
@@ -268,7 +268,7 @@
 # Delete a Recipient #
 # DELETE /contactdb/recipients/{recipient_id} #
 
-recipient_id = "test_url_param"
+recipient_id = 'test_url_param'
 response = sg.client.contactdb.recipients._(recipient_id).delete
 puts response.status_code
 puts response.body
@@ -278,7 +278,7 @@
 # Retrieve the lists that a recipient is on #
 # GET /contactdb/recipients/{recipient_id}/lists #
 
-recipient_id = "test_url_param"
+recipient_id = 'test_url_param'
 response = sg.client.contactdb.recipients._(recipient_id).lists.get
 puts response.status_code
 puts response.body
@@ -352,7 +352,7 @@
   "name": "The Millers"
 }')
 params = JSON.parse('{"segment_id": "test_string"}')
-segment_id = "test_url_param"
+segment_id = 'test_url_param'
 response = sg.client.contactdb.segments._(segment_id).patch(request_body: data, query_params: params)
 puts response.status_code
 puts response.body
@@ -363,7 +363,7 @@
 # GET /contactdb/segments/{segment_id} #
 
 params = JSON.parse('{"segment_id": 1}')
-segment_id = "test_url_param"
+segment_id = 'test_url_param'
 response = sg.client.contactdb.segments._(segment_id).get(query_params: params)
 puts response.status_code
 puts response.body
@@ -374,7 +374,7 @@
 # DELETE /contactdb/segments/{segment_id} #
 
 params = JSON.parse('{"delete_contacts": "true"}')
-segment_id = "test_url_param"
+segment_id = 'test_url_param'
 response = sg.client.contactdb.segments._(segment_id).delete(query_params: params)
 puts response.status_code
 puts response.body
@@ -385,7 +385,7 @@
 # GET /contactdb/segments/{segment_id}/recipients #
 
 params = JSON.parse('{"page": 1, "page_size": 1}')
-segment_id = "test_url_param"
+segment_id = 'test_url_param'
 response = sg.client.contactdb.segments._(segment_id).recipients.get(query_params: params)
 puts response.status_code
 puts response.body
diff --git a/examples/emailactivity/emailactivity.rb b/examples/emailactivity/emailactivity.rb
index 6634eb36..5485f6cf 100644
--- a/examples/emailactivity/emailactivity.rb
+++ b/examples/emailactivity/emailactivity.rb
@@ -27,7 +27,7 @@
 # GET /messages/{msg_id} #
 
 msg_id = "test_url_param"
-response = sg.client.messages._(msg_id).get()
+response = sg.client.messages._(msg_id).get
 puts response.status_code
 puts response.body
 puts response.headers
@@ -36,7 +36,7 @@
 # Request a CSV #
 # POST /messages/download #
 
-response = sg.client.messages.download.post()
+response = sg.client.messages.download.post
 puts response.status_code
 puts response.body
 puts response.headers
diff --git a/examples/helpers/eventwebhook/example.rb b/examples/helpers/eventwebhook/example.rb
index b99c7161..92ad81c1 100644
--- a/examples/helpers/eventwebhook/example.rb
+++ b/examples/helpers/eventwebhook/example.rb
@@ -8,9 +8,9 @@ def is_valid_signature(request)
   ec_public_key = event_webhook.convert_public_key_to_ecdsa(public_key)
 
   event_webhook.verify_signature(
-      ec_public_key,
-      request.body.read,
-      request.env[SendGrid::EventWebhookHeader::SIGNATURE],
-      request.env[SendGrid::EventWebhookHeader::TIMESTAMP]
+    ec_public_key,
+    request.body.read,
+    request.env[SendGrid::EventWebhookHeader::SIGNATURE],
+    request.env[SendGrid::EventWebhookHeader::TIMESTAMP]
   )
 end
diff --git a/examples/helpers/mail/example.rb b/examples/helpers/mail/example.rb
index 41cf546e..b248a588 100644
--- a/examples/helpers/mail/example.rb
+++ b/examples/helpers/mail/example.rb
@@ -36,7 +36,7 @@ def kitchen_sink
   personalization.add_substitution(Substitution.new(key: '%city%', value: 'Denver'))
   personalization.add_custom_arg(CustomArg.new(key: 'user_id', value: '343'))
   personalization.add_custom_arg(CustomArg.new(key: 'type', value: 'marketing'))
-  personalization.send_at = 1443636843
+  personalization.send_at = 1_443_636_843
   mail.add_personalization(personalization)
 
   personalization2 = Personalization.new
@@ -53,7 +53,7 @@ def kitchen_sink
   personalization2.add_substitution(Substitution.new(key: '%city%', value: 'Denver'))
   personalization2.add_custom_arg(CustomArg.new(key: 'user_id', value: '343'))
   personalization2.add_custom_arg(CustomArg.new(key: 'type', value: 'marketing'))
-  personalization2.send_at = 1443636843
+  personalization2.send_at = 1_443_636_843
   mail.add_personalization(personalization2)
 
   mail.add_content(Content.new(type: 'text/plain', value: 'some text here'))
@@ -89,7 +89,7 @@ def kitchen_sink
   mail.add_custom_arg(CustomArg.new(key: 'campaign', value: 'welcome'))
   mail.add_custom_arg(CustomArg.new(key: 'weekday', value: 'morning'))
 
-  mail.send_at = 1443636842
+  mail.send_at = 1_443_636_842
 
   # This must be a valid [batch ID](https://sendgrid.com/docs/API_Reference/SMTP_API/scheduling_parameters.html) to work
   # mail.batch_id = 'sendgrid_batch_id'
@@ -132,8 +132,8 @@ def dynamic_template_data_hello_world
   personalization = Personalization.new
   personalization.add_to(Email.new(email: 'test1@example.com', name: 'Example User'))
   personalization.add_dynamic_template_data(
-    "variable" => [
-      { "foo" => "bar" }, { "foo" => "baz" }
+    'variable' => [
+      { 'foo' => 'bar' }, { 'foo' => 'baz' }
     ]
   )
   mail.add_personalization(personalization)
diff --git a/examples/helpers/settings/example.rb b/examples/helpers/settings/example.rb
index 3cdb8494..0c2455e0 100644
--- a/examples/helpers/settings/example.rb
+++ b/examples/helpers/settings/example.rb
@@ -11,7 +11,7 @@
 puts response.headers
 
 # Turn on bcc settings
-response = settings.update_bcc(enabled: true, email: "email@example.com")
+response = settings.update_bcc(enabled: true, email: 'email@example.com')
 puts response.status_code
 puts response.body
 puts response.headers
diff --git a/examples/helpers/stats/example.rb b/examples/helpers/stats/example.rb
index d50acdbf..109a0349 100644
--- a/examples/helpers/stats/example.rb
+++ b/examples/helpers/stats/example.rb
@@ -7,7 +7,7 @@
 stats = SendGrid::EmailStats.new(sendgrid_client: sg_client)
 
 # Fetch stats by day, between 2 dates
-from = Date.new(2017, 10, 01)
+from = Date.new(2017, 10, 1)
 to = Date.new(2017, 10, 12)
 
 email_stats = stats.by_day(from, to)
@@ -25,7 +25,7 @@
 end
 
 # Fetch stats by week, between 2 dates for a category
-from = Date.new(2017, 10, 01)
+from = Date.new(2017, 10, 1)
 to = Date.new(2017, 10, 12)
 category = 'abcd'
 
diff --git a/examples/ips/ips.rb b/examples/ips/ips.rb
index eb341877..fc625cee 100644
--- a/examples/ips/ips.rb
+++ b/examples/ips/ips.rb
@@ -28,7 +28,7 @@
 params = {}
 response = sg.client.ips.get(query_params: params)
 all_ips = JSON.parse(response.body)
-unassigned_ips = all_ips.select {|ip| ip.subusers.empty?}
+unassigned_ips = all_ips.select { |ip| ip.subusers.empty? }
 puts response.status_code
 puts response.body
 puts unassigned_ips
@@ -62,7 +62,7 @@
 data = JSON.parse('{
   "name": "new_pool_name"
 }')
-pool_name = "test_url_param"
+pool_name = 'test_url_param'
 response = sg.client.ips.pools._(pool_name).put(request_body: data)
 puts response.status_code
 puts response.body
@@ -72,7 +72,7 @@
 # Retrieve all IPs in a specified pool. #
 # GET /ips/pools/{pool_name} #
 
-pool_name = "test_url_param"
+pool_name = 'test_url_param'
 response = sg.client.ips.pools._(pool_name).get
 puts response.status_code
 puts response.body
@@ -82,7 +82,7 @@
 # Delete an IP pool. #
 # DELETE /ips/pools/{pool_name} #
 
-pool_name = "test_url_param"
+pool_name = 'test_url_param'
 response = sg.client.ips.pools._(pool_name).delete
 puts response.status_code
 puts response.body
@@ -95,7 +95,7 @@
 data = JSON.parse('{
   "ip": "0.0.0.0"
 }')
-pool_name = "test_url_param"
+pool_name = 'test_url_param'
 response = sg.client.ips.pools._(pool_name).ips.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -105,8 +105,8 @@
 # Remove an IP address from a pool. #
 # DELETE /ips/pools/{pool_name}/ips/{ip} #
 
-pool_name = "test_url_param"
-ip = "test_url_param"
+pool_name = 'test_url_param'
+ip = 'test_url_param'
 response = sg.client.ips.pools._(pool_name).ips._(ip).delete
 puts response.status_code
 puts response.body
@@ -137,7 +137,7 @@
 # Retrieve warmup status for a specific IP address #
 # GET /ips/warmup/{ip_address} #
 
-ip_address = "test_url_param"
+ip_address = 'test_url_param'
 response = sg.client.ips.warmup._(ip_address).get
 puts response.status_code
 puts response.body
@@ -147,7 +147,7 @@
 # Remove an IP from warmup #
 # DELETE /ips/warmup/{ip_address} #
 
-ip_address = "test_url_param"
+ip_address = 'test_url_param'
 response = sg.client.ips.warmup._(ip_address).delete
 puts response.status_code
 puts response.body
@@ -157,7 +157,7 @@
 # Retrieve all IP pools an IP address belongs to #
 # GET /ips/{ip_address} #
 
-ip_address = "test_url_param"
+ip_address = 'test_url_param'
 response = sg.client.ips._(ip_address).get
 puts response.status_code
 puts response.body
diff --git a/examples/mail/mail.rb b/examples/mail/mail.rb
index fe8b8767..ad419c22 100644
--- a/examples/mail/mail.rb
+++ b/examples/mail/mail.rb
@@ -1,9 +1,7 @@
 require 'sendgrid-ruby'
 
-
 sg = SendGrid::API.new(api_key: ENV['SENDGRID_API_KEY'])
 
-
 ##################################################
 # Create a batch ID #
 # POST /mail/batch #
@@ -17,7 +15,7 @@
 # Validate batch ID #
 # GET /mail/batch/{batch_id} #
 
-batch_id = "test_url_param"
+batch_id = 'test_url_param'
 response = sg.client.mail.batch._(batch_id).get
 puts response.status_code
 puts response.body
@@ -166,8 +164,7 @@
     }
   }
 }')
-response = sg.client.mail._("send").post(request_body: data)
+response = sg.client.mail._('send').post(request_body: data)
 puts response.status_code
 puts response.body
 puts response.headers
-
diff --git a/examples/scopes/scopes.rb b/examples/scopes/scopes.rb
index 75447698..adec506b 100644
--- a/examples/scopes/scopes.rb
+++ b/examples/scopes/scopes.rb
@@ -1,8 +1,6 @@
 require_relative '../../lib/sendgrid-ruby.rb'
-
 sg = SendGrid::API.new(api_key: ENV['SENDGRID_API_KEY'])
 
-
 ##################################################
 # Retrieve a list of scopes for which this user has access. #
 # GET /scopes #
@@ -16,7 +14,6 @@
 # Update the name & scopes of an API Key #
 # PUT /api_keys/{api_key_id} #
 
-
 scopes = [
   "user.profile.read",
   "user.profile.update"
diff --git a/examples/senderauthentication/senderauthentication.rb b/examples/senderauthentication/senderauthentication.rb
index 17d72431..5a9b2ab6 100644
--- a/examples/senderauthentication/senderauthentication.rb
+++ b/examples/senderauthentication/senderauthentication.rb
@@ -68,7 +68,7 @@
   "custom_spf": true,
   "default": false
 }')
-domain_id = "test_url_param"
+domain_id = 'test_url_param'
 response = sg.client.whitelabel.domains._(domain_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -78,7 +78,7 @@
 # Retrieve a domain authentication. #
 # GET /whitelabel/domains/{domain_id} #
 
-domain_id = "test_url_param"
+domain_id = 'test_url_param'
 response = sg.client.whitelabel.domains._(domain_id).get
 puts response.status_code
 puts response.body
@@ -88,7 +88,7 @@
 # Delete a domain authentication. #
 # DELETE /whitelabel/domains/{domain_id} #
 
-domain_id = "test_url_param"
+domain_id = 'test_url_param'
 response = sg.client.whitelabel.domains._(domain_id).delete
 puts response.status_code
 puts response.body
@@ -101,7 +101,7 @@
 data = JSON.parse('{
   "username": "jane@example.com"
 }')
-domain_id = "test_url_param"
+domain_id = 'test_url_param'
 response = sg.client.whitelabel.domains._(domain_id).subuser.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -114,7 +114,7 @@
 data = JSON.parse('{
   "ip": "192.168.0.1"
 }')
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.domains._(id).ips.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -124,8 +124,8 @@
 # Remove an IP from a domain authentication. #
 # DELETE /whitelabel/domains/{id}/ips/{ip} #
 
-id = "test_url_param"
-ip = "test_url_param"
+id = 'test_url_param'
+ip = 'test_url_param'
 response = sg.client.whitelabel.domains._(id).ips._(ip).delete
 puts response.status_code
 puts response.body
@@ -135,7 +135,7 @@
 # Validate a domain authentication. #
 # POST /whitelabel/domains/{id}/validate #
 
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.domains._(id).validate.post
 puts response.status_code
 puts response.body
@@ -169,7 +169,7 @@
 # Retrieve a reverse DNS record #
 # GET /whitelabel/ips/{id} #
 
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.ips._(id).get
 puts response.status_code
 puts response.body
@@ -179,7 +179,7 @@
 # Delete a reverse DNS record #
 # DELETE /whitelabel/ips/{id} #
 
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.ips._(id).delete
 puts response.status_code
 puts response.body
@@ -189,7 +189,7 @@
 # Validate a reverse DNS record #
 # POST /whitelabel/ips/{id}/validate #
 
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.ips._(id).validate.post
 puts response.status_code
 puts response.body
@@ -257,7 +257,7 @@
 data = JSON.parse('{
   "default": true
 }')
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.links._(id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -267,7 +267,7 @@
 # Retrieve a Link Branding #
 # GET /whitelabel/links/{id} #
 
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.links._(id).get
 puts response.status_code
 puts response.body
@@ -277,7 +277,7 @@
 # Delete a Link Branding #
 # DELETE /whitelabel/links/{id} #
 
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.links._(id).delete
 puts response.status_code
 puts response.body
@@ -287,7 +287,7 @@
 # Validate a Link Branding #
 # POST /whitelabel/links/{id}/validate #
 
-id = "test_url_param"
+id = 'test_url_param'
 response = sg.client.whitelabel.links._(id).validate.post
 puts response.status_code
 puts response.body
@@ -300,7 +300,7 @@
 data = JSON.parse('{
   "username": "jane@example.com"
 }')
-link_id = "test_url_param"
+link_id = 'test_url_param'
 response = sg.client.whitelabel.links._(link_id).subuser.post(request_body: data)
 puts response.status_code
 puts response.body
diff --git a/examples/senders/senders.rb b/examples/senders/senders.rb
index 8928243b..e9b2239f 100644
--- a/examples/senders/senders.rb
+++ b/examples/senders/senders.rb
@@ -58,7 +58,7 @@
   "state": "Colorado",
   "zip": "80202"
 }')
-sender_id = "test_url_param"
+sender_id = 'test_url_param'
 response = sg.client.senders._(sender_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -68,7 +68,7 @@
 # View a Sender Identity #
 # GET /senders/{sender_id} #
 
-sender_id = "test_url_param"
+sender_id = 'test_url_param'
 response = sg.client.senders._(sender_id).get
 puts response.status_code
 puts response.body
@@ -78,7 +78,7 @@
 # Delete a Sender Identity #
 # DELETE /senders/{sender_id} #
 
-sender_id = "test_url_param"
+sender_id = 'test_url_param'
 response = sg.client.senders._(sender_id).delete
 puts response.status_code
 puts response.body
@@ -88,7 +88,7 @@
 # Resend Sender Identity Verification #
 # POST /senders/{sender_id}/resend_verification #
 
-sender_id = "test_url_param"
+sender_id = 'test_url_param'
 response = sg.client.senders._(sender_id).resend_verification.post
 puts response.status_code
 puts response.body
diff --git a/examples/subusers/subusers.rb b/examples/subusers/subusers.rb
index e56c2abe..0df9d31f 100644
--- a/examples/subusers/subusers.rb
+++ b/examples/subusers/subusers.rb
@@ -77,7 +77,7 @@
 data = JSON.parse('{
   "disabled": false
 }')
-subuser_name = "test_url_param"
+subuser_name = 'test_url_param'
 response = sg.client.subusers._(subuser_name).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -87,7 +87,7 @@
 # Delete a subuser #
 # DELETE /subusers/{subuser_name} #
 
-subuser_name = "test_url_param"
+subuser_name = 'test_url_param'
 response = sg.client.subusers._(subuser_name).delete
 puts response.status_code
 puts response.body
@@ -100,7 +100,7 @@
 data = JSON.parse('[
   "127.0.0.1"
 ]')
-subuser_name = "test_url_param"
+subuser_name = 'test_url_param'
 response = sg.client.subusers._(subuser_name).ips.put(request_body: data)
 puts response.status_code
 puts response.body
@@ -114,7 +114,7 @@
   "email": "example@example.com",
   "frequency": 500
 }')
-subuser_name = "test_url_param"
+subuser_name = 'test_url_param'
 response = sg.client.subusers._(subuser_name).monitor.put(request_body: data)
 puts response.status_code
 puts response.body
@@ -128,7 +128,7 @@
   "email": "example@example.com",
   "frequency": 50000
 }')
-subuser_name = "test_url_param"
+subuser_name = 'test_url_param'
 response = sg.client.subusers._(subuser_name).monitor.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -138,7 +138,7 @@
 # Retrieve monitor settings for a subuser #
 # GET /subusers/{subuser_name}/monitor #
 
-subuser_name = "test_url_param"
+subuser_name = 'test_url_param'
 response = sg.client.subusers._(subuser_name).monitor.get
 puts response.status_code
 puts response.body
@@ -148,7 +148,7 @@
 # Delete monitor settings #
 # DELETE /subusers/{subuser_name}/monitor #
 
-subuser_name = "test_url_param"
+subuser_name = 'test_url_param'
 response = sg.client.subusers._(subuser_name).monitor.delete
 puts response.status_code
 puts response.body
@@ -159,7 +159,7 @@
 # GET /subusers/{subuser_name}/stats/monthly #
 
 params = JSON.parse('{"date": "test_string", "sort_by_direction": "asc", "limit": 1, "sort_by_metric": "test_string", "offset": 1}')
-subuser_name = "test_url_param"
+subuser_name = 'test_url_param'
 response = sg.client.subusers._(subuser_name).stats.monthly.get(query_params: params)
 puts response.status_code
 puts response.body
diff --git a/examples/suppression/suppression.rb b/examples/suppression/suppression.rb
index 27b04ff6..4bb07591 100644
--- a/examples/suppression/suppression.rb
+++ b/examples/suppression/suppression.rb
@@ -1,9 +1,7 @@
 require 'sendgrid-ruby'
 
-
 sg = SendGrid::API.new(api_key: ENV['SENDGRID_API_KEY'])
 
-
 ##################################################
 # Retrieve all blocks #
 # GET /suppression/blocks #
@@ -34,7 +32,7 @@
 # Retrieve a specific block #
 # GET /suppression/blocks/{email} #
 
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.suppression.blocks._(email).get
 puts response.status_code
 puts response.body
@@ -44,7 +42,7 @@
 # Delete a specific block #
 # DELETE /suppression/blocks/{email} #
 
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.suppression.blocks._(email).delete
 puts response.status_code
 puts response.body
@@ -80,7 +78,7 @@
 # Retrieve a Bounce #
 # GET /suppression/bounces/{email} #
 
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.suppression.bounces._(email).get
 puts response.status_code
 puts response.body
@@ -91,7 +89,7 @@
 # DELETE /suppression/bounces/{email} #
 
 params = JSON.parse('{"email_address": "example@example.com"}')
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.suppression.bounces._(email).delete(query_params: params)
 puts response.status_code
 puts response.body
@@ -127,7 +125,7 @@
 # Retrieve a specific invalid email #
 # GET /suppression/invalid_emails/{email} #
 
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.suppression.invalid_emails._(email).get
 puts response.status_code
 puts response.body
@@ -137,7 +135,7 @@
 # Delete a specific invalid email #
 # DELETE /suppression/invalid_emails/{email} #
 
-email = "test_url_param"
+email = 'test_url_param'
 response = sg.client.suppression.invalid_emails._(email).delete
 puts response.status_code
 puts response.body
@@ -147,8 +145,8 @@
 # Retrieve a specific spam report #
 # GET /suppression/spam_report/{email} #
 
-email = "test_url_param"
-response = sg.client.suppression.spam_report._(email).get()
+email = 'test_url_param'
+response = sg.client.suppression.spam_report._(email).get
 puts response.status_code
 puts response.body
 puts response.headers
@@ -157,8 +155,8 @@
 # Delete a specific spam report #
 # DELETE /suppression/spam_report/{email} #
 
-email = "test_url_param"
-response = sg.client.suppression.spam_reports._(email).delete()
+email = 'test_url_param'
+response = sg.client.suppression.spam_reports._(email).delete
 puts response.status_code
 puts response.body
 puts response.headers
@@ -198,4 +196,3 @@
 puts response.status_code
 puts response.body
 puts response.headers
-
diff --git a/examples/templates/templates.rb b/examples/templates/templates.rb
index 3c4338a3..49c16ffc 100644
--- a/examples/templates/templates.rb
+++ b/examples/templates/templates.rb
@@ -30,7 +30,7 @@
 data = JSON.parse('{
   "name": "new_example_name"
 }')
-template_id = "test_url_param"
+template_id = 'test_url_param'
 response = sg.client.templates._(template_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -40,7 +40,7 @@
 # Retrieve a single transactional template. #
 # GET /templates/{template_id} #
 
-template_id = "test_url_param"
+template_id = 'test_url_param'
 response = sg.client.templates._(template_id).get
 puts response.status_code
 puts response.body
@@ -50,7 +50,7 @@
 # Delete a template. #
 # DELETE /templates/{template_id} #
 
-template_id = "test_url_param"
+template_id = 'test_url_param'
 response = sg.client.templates._(template_id).delete
 puts response.status_code
 puts response.body
@@ -68,7 +68,7 @@
   "subject": "<%subject%>",
   "template_id": "ddb96bbc-9b92-425e-8979-99464621b543"
 }')
-template_id = "test_url_param"
+template_id = 'test_url_param'
 response = sg.client.templates._(template_id).versions.post(request_body: data)
 puts response.status_code
 puts response.body
@@ -85,8 +85,8 @@
   "plain_content": "<%body%>",
   "subject": "<%subject%>"
 }')
-template_id = "test_url_param"
-version_id = "test_url_param"
+template_id = 'test_url_param'
+version_id = 'test_url_param'
 response = sg.client.templates._(template_id).versions._(version_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -96,8 +96,8 @@
 # Retrieve a specific transactional template version. #
 # GET /templates/{template_id}/versions/{version_id} #
 
-template_id = "test_url_param"
-version_id = "test_url_param"
+template_id = 'test_url_param'
+version_id = 'test_url_param'
 response = sg.client.templates._(template_id).versions._(version_id).get
 puts response.status_code
 puts response.body
@@ -107,8 +107,8 @@
 # Delete a transactional template version. #
 # DELETE /templates/{template_id}/versions/{version_id} #
 
-template_id = "test_url_param"
-version_id = "test_url_param"
+template_id = 'test_url_param'
+version_id = 'test_url_param'
 response = sg.client.templates._(template_id).versions._(version_id).delete
 puts response.status_code
 puts response.body
@@ -118,8 +118,8 @@
 # Activate a transactional template version. #
 # POST /templates/{template_id}/versions/{version_id}/activate #
 
-template_id = "test_url_param"
-version_id = "test_url_param"
+template_id = 'test_url_param'
+version_id = 'test_url_param'
 response = sg.client.templates._(template_id).versions._(version_id).activate.post
 puts response.status_code
 puts response.body
diff --git a/examples/user/user.rb b/examples/user/user.rb
index 8ada0e05..0f8f4f3f 100644
--- a/examples/user/user.rb
+++ b/examples/user/user.rb
@@ -106,7 +106,7 @@
 data = JSON.parse('{
   "status": "pause"
 }')
-batch_id = "test_url_param"
+batch_id = 'test_url_param'
 response = sg.client.user.scheduled_sends._(batch_id).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -116,7 +116,7 @@
 # Retrieve scheduled send #
 # GET /user/scheduled_sends/{batch_id} #
 
-batch_id = "test_url_param"
+batch_id = 'test_url_param'
 response = sg.client.user.scheduled_sends._(batch_id).get
 puts response.status_code
 puts response.body
@@ -126,7 +126,7 @@
 # Delete a cancellation or pause of a scheduled send #
 # DELETE /user/scheduled_sends/{batch_id} #
 
-batch_id = "test_url_param"
+batch_id = 'test_url_param'
 response = sg.client.user.scheduled_sends._(batch_id).delete
 puts response.status_code
 puts response.body
@@ -253,7 +253,7 @@
   "spam_check": false,
   "url": "http://newdomain.com/parse"
 }')
-hostname = "test_url_param"
+hostname = 'test_url_param'
 response = sg.client.user.webhooks.parse.settings._(hostname).patch(request_body: data)
 puts response.status_code
 puts response.body
@@ -263,7 +263,7 @@
 # Retrieve a specific parse setting #
 # GET /user/webhooks/parse/settings/{hostname} #
 
-hostname = "test_url_param"
+hostname = 'test_url_param'
 response = sg.client.user.webhooks.parse.settings._(hostname).get
 puts response.status_code
 puts response.body
@@ -273,7 +273,7 @@
 # Delete a parse setting #
 # DELETE /user/webhooks/parse/settings/{hostname} #
 
-hostname = "test_url_param"
+hostname = 'test_url_param'
 response = sg.client.user.webhooks.parse.settings._(hostname).delete
 puts response.status_code
 puts response.body
diff --git a/lib/rack/sendgrid_webhook_verification.rb b/lib/rack/sendgrid_webhook_verification.rb
index d9faa450..cf952d60 100644
--- a/lib/rack/sendgrid_webhook_verification.rb
+++ b/lib/rack/sendgrid_webhook_verification.rb
@@ -27,6 +27,7 @@ def initialize(app, public_key, *paths)
 
     def call(env)
       return @app.call(env) unless env['PATH_INFO'].match(@path_regex)
+
       request = Rack::Request.new(env)
 
       event_webhook = SendGrid::EventWebhook.new
@@ -39,9 +40,9 @@ def call(env)
       )
 
       if verified
-        return @app.call(env)
+        @app.call(env)
       else
-        return [
+        [
           403,
           { 'Content-Type' => 'text/plain' },
           ['SendGrid Request Verification Failed.']
diff --git a/lib/sendgrid/base_interface.rb b/lib/sendgrid/base_interface.rb
index c333f175..c288e632 100644
--- a/lib/sendgrid/base_interface.rb
+++ b/lib/sendgrid/base_interface.rb
@@ -17,7 +17,7 @@ class BaseInterface
   def initialize(auth:, host:, request_headers: nil, version: nil, impersonate_subuser: nil)
     @auth = auth
     @host = host
-    @version = version ? version : 'v3'
+    @version = version || 'v3'
     @impersonate_subuser = impersonate_subuser
     @user_agent = "sendgrid/#{SendGrid::VERSION};ruby"
     @request_headers = JSON.parse('
diff --git a/lib/sendgrid/helpers/eventwebhook/eventwebhook.rb b/lib/sendgrid/helpers/eventwebhook/eventwebhook.rb
index 2596dcf7..3ea3f137 100644
--- a/lib/sendgrid/helpers/eventwebhook/eventwebhook.rb
+++ b/lib/sendgrid/helpers/eventwebhook/eventwebhook.rb
@@ -25,15 +25,13 @@ def verify_signature(public_key, payload, signature, timestamp)
       payload_digest = Digest::SHA256.digest(timestamped_playload)
       decoded_signature = Base64.decode64(signature)
       public_key.dsa_verify_asn1(payload_digest, decoded_signature)
-    rescue
+    rescue StandardError
       false
     end
 
     def verify_engine
       # JRuby does not fully support ECDSA: https://github.com/jruby/jruby-openssl/issues/193
-      if RUBY_PLATFORM == "java"
-        raise NotSupportedError, "Event Webhook verification is not supported by JRuby"
-      end
+      raise NotSupportedError, "Event Webhook verification is not supported by JRuby" if RUBY_PLATFORM == "java"
     end
 
     class Error < ::RuntimeError
@@ -46,7 +44,7 @@ class NotSupportedError < Error
   # This class lists headers that get posted to the webhook. Read the docs for
   # more details: https://sendgrid.com/docs/for-developers/tracking-events/event
   class EventWebhookHeader
-    SIGNATURE = "HTTP_X_TWILIO_EMAIL_EVENT_WEBHOOK_SIGNATURE"
-    TIMESTAMP = "HTTP_X_TWILIO_EMAIL_EVENT_WEBHOOK_TIMESTAMP"
+    SIGNATURE = "HTTP_X_TWILIO_EMAIL_EVENT_WEBHOOK_SIGNATURE".freeze
+    TIMESTAMP = "HTTP_X_TWILIO_EMAIL_EVENT_WEBHOOK_TIMESTAMP".freeze
   end
 end
diff --git a/lib/sendgrid/helpers/ip_management/ip_management.rb b/lib/sendgrid/helpers/ip_management/ip_management.rb
index d6007ffd..1112fcad 100644
--- a/lib/sendgrid/helpers/ip_management/ip_management.rb
+++ b/lib/sendgrid/helpers/ip_management/ip_management.rb
@@ -11,7 +11,7 @@ def initialize(sendgrid_client:)
     def unassigned
       response = @sendgrid_client.ips.get
       ips = JSON.parse(response.body)
-      ips.select {|ip| ip.subusers.empty?}
+      ips.select { |ip| ip.subusers.empty? }
     end
   end
 end
diff --git a/lib/sendgrid/helpers/mail/attachment.rb b/lib/sendgrid/helpers/mail/attachment.rb
index e669ded7..0386fc75 100644
--- a/lib/sendgrid/helpers/mail/attachment.rb
+++ b/lib/sendgrid/helpers/mail/attachment.rb
@@ -20,16 +20,16 @@ def content=(content)
     def content
       return @encoded_content if @encoded_content
 
-      if @content.respond_to?(:read)
-        @encoded_content = encode @content
-      else
-        @encoded_content = @content
-      end
+      @encoded_content = if @content.respond_to?(:read)
+                           encode @content
+                         else
+                           @content
+                         end
     end
 
     def to_json(*)
       {
-        'content' => self.content,
+        'content' => content,
         'type' => type,
         'filename' => filename,
         'disposition' => disposition,
diff --git a/lib/sendgrid/helpers/mail/email.rb b/lib/sendgrid/helpers/mail/email.rb
index 030339e6..6d1e30a9 100644
--- a/lib/sendgrid/helpers/mail/email.rb
+++ b/lib/sendgrid/helpers/mail/email.rb
@@ -2,7 +2,6 @@
 
 module SendGrid
   class Email
-
     attr_accessor :email, :name
 
     def initialize(email: nil, name: nil)
diff --git a/lib/sendgrid/helpers/mail/header.rb b/lib/sendgrid/helpers/mail/header.rb
index d104dfaf..c9a7227f 100644
--- a/lib/sendgrid/helpers/mail/header.rb
+++ b/lib/sendgrid/helpers/mail/header.rb
@@ -11,7 +11,7 @@ def initialize(key: nil, value: nil)
 
     def to_json(*)
       {
-        'header' => self.header
+        'header' => header
       }.delete_if { |_, value| value.to_s.strip == '' }
     end
   end
diff --git a/lib/sendgrid/helpers/mail/mail.rb b/lib/sendgrid/helpers/mail/mail.rb
index 6230919e..2b32af80 100644
--- a/lib/sendgrid/helpers/mail/mail.rb
+++ b/lib/sendgrid/helpers/mail/mail.rb
@@ -4,7 +4,6 @@
 
 module SendGrid
   class Mail
-
     attr_accessor :subject, :ip_pool_name, :template_id, :send_at, :batch_id
     attr_reader :personalizations, :contents, :attachments, :categories, :sections, :headers, :custom_args
     attr_writer :from, :asm, :mail_settings, :tracking_settings, :reply_to
@@ -28,14 +27,14 @@ def initialize(from_email = nil, subj = nil, to_email = nil, cont = nil)
       @tracking_settings = nil
       @reply_to = nil
 
-      unless from_email.nil? && subj.nil? && to_email.nil? && cont.nil?
-        self.from = from_email
-        self.subject = subj
-        personalization = Personalization.new
-        personalization.add_to(to_email)
-        add_personalization(personalization)
-        add_content(cont)
-      end
+      return if from_email.nil? && subj.nil? && to_email.nil? && cont.nil?
+
+      self.from = from_email
+      self.subject = subj
+      personalization = Personalization.new
+      personalization.add_to(to_email)
+      add_personalization(personalization)
+      add_content(cont)
     end
 
     def from
@@ -53,7 +52,7 @@ def add_content(content)
     def check_for_secrets(patterns)
       contents = @contents.map { |content| content['value'] }.join(' ')
       patterns.each do |pattern|
-        raise SecurityError.new('Content contains sensitive information.') if contents.match(pattern)
+        raise SecurityError, 'Content contains sensitive information.' if contents.match(pattern)
       end
     end
 
diff --git a/lib/sendgrid/helpers/mail/mail_settings.rb b/lib/sendgrid/helpers/mail/mail_settings.rb
index 8b764203..875c4859 100644
--- a/lib/sendgrid/helpers/mail/mail_settings.rb
+++ b/lib/sendgrid/helpers/mail/mail_settings.rb
@@ -16,7 +16,6 @@ def sandbox_mode
       @sandbox_mode.nil? ? nil : @sandbox_mode.to_json
     end
 
-
     def bypass_list_management
       @bypass_list_management.nil? ? nil : @bypass_list_management.to_json
     end
diff --git a/lib/sendgrid/helpers/mail/personalization.rb b/lib/sendgrid/helpers/mail/personalization.rb
index 70383e9f..bc1ee13a 100644
--- a/lib/sendgrid/helpers/mail/personalization.rb
+++ b/lib/sendgrid/helpers/mail/personalization.rb
@@ -2,7 +2,6 @@
 
 module SendGrid
   class Personalization
-
     attr_reader :tos, :ccs, :bccs, :headers, :substitutions, :custom_args,
                 :dynamic_template_data
 
diff --git a/lib/sendgrid/helpers/mail/substitution.rb b/lib/sendgrid/helpers/mail/substitution.rb
index 92222c4e..738f4f5b 100644
--- a/lib/sendgrid/helpers/mail/substitution.rb
+++ b/lib/sendgrid/helpers/mail/substitution.rb
@@ -11,7 +11,7 @@ def initialize(key: nil, value: nil)
 
     def to_json(*)
       {
-        'substitution' => self.substitution
+        'substitution' => substitution
       }.delete_if { |_, value| value.to_s.strip == '' }
     end
   end
diff --git a/lib/sendgrid/helpers/permissions/scope.rb b/lib/sendgrid/helpers/permissions/scope.rb
index 944ab4d2..c7bd3ba9 100644
--- a/lib/sendgrid/helpers/permissions/scope.rb
+++ b/lib/sendgrid/helpers/permissions/scope.rb
@@ -4,7 +4,7 @@
 module SendGrid
   class Scope
     SCOPES = YAML.load_file(File.dirname(__FILE__) + '/scopes.yml').freeze
-    
+
     class << self
       def admin_permissions
         SCOPES.values.map(&:values).flatten
diff --git a/lib/sendgrid/sendgrid.rb b/lib/sendgrid/sendgrid.rb
index be4dc895..8207a389 100644
--- a/lib/sendgrid/sendgrid.rb
+++ b/lib/sendgrid/sendgrid.rb
@@ -12,7 +12,7 @@ class API < BaseInterface
     #
     def initialize(api_key:, host: nil, request_headers: nil, version: nil, impersonate_subuser: nil)
       auth = "Bearer #{api_key}"
-      host = 'https://api.sendgrid.com' unless host
+      host ||= 'https://api.sendgrid.com'
 
       super(auth: auth, host: host, request_headers: request_headers, version: version, impersonate_subuser: impersonate_subuser)
     end
diff --git a/lib/sendgrid/twilio_email.rb b/lib/sendgrid/twilio_email.rb
index 13c5cbdb..0d8ab0a6 100644
--- a/lib/sendgrid/twilio_email.rb
+++ b/lib/sendgrid/twilio_email.rb
@@ -13,7 +13,7 @@ class API < BaseInterface
     #
     def initialize(username:, password:, host: nil, request_headers: nil, version: nil, impersonate_subuser: nil)
       auth = "Basic #{Base64.strict_encode64("#{username}:#{password}")}"
-      host = 'https://email.twilio.com' unless host
+      host ||= 'https://email.twilio.com'
 
       super(auth: auth, host: host, request_headers: request_headers, version: version, impersonate_subuser: impersonate_subuser)
     end
diff --git a/mail_helper_v3.md b/mail_helper_v3.md
index 1b58570b..23b509dc 100644
--- a/mail_helper_v3.md
+++ b/mail_helper_v3.md
@@ -263,7 +263,7 @@ attachments = [
                              'base64 encoded content',
                              'image/png',
                              'inline',
-                             'Banner 2'),                             
+                             'Banner 2'),
 ]
 msg.add_attachments(attachments)
 
@@ -279,7 +279,7 @@ msg.set_global_headers(global_headers)
 msg.add_section('%section1%', 'Substitution for Section 1 Tag')
 sections = [
     '%section2%' => 'Substitution for Section 2 Tag',
-    '%section3%' => 'Substitution for Section 3 Tag'    
+    '%section3%' => 'Substitution for Section 3 Tag'
 ]
 msg.add_sections(sections)
 
diff --git a/sendgrid-ruby.gemspec b/sendgrid-ruby.gemspec
index 8c65b77c..279d0c39 100644
--- a/sendgrid-ruby.gemspec
+++ b/sendgrid-ruby.gemspec
@@ -1,5 +1,4 @@
-# coding: utf-8
-lib = File.expand_path('../lib', __FILE__)
+lib = File.expand_path('lib', __dir__)
 $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 require 'sendgrid/version'
 
@@ -20,13 +19,13 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(/^(test|spec|features)/)
   spec.require_paths = ['lib']
   spec.add_dependency 'ruby_http_client', '~> 3.4'
-  spec.add_development_dependency 'sinatra', '>= 1.4.7', '< 3'
-  spec.add_development_dependency 'rake', '~> 13.0'
-  spec.add_development_dependency 'rspec'
-  spec.add_development_dependency 'pry'
   spec.add_development_dependency 'faker'
-  spec.add_development_dependency 'rubocop'
   spec.add_development_dependency 'minitest', '~> 5.9'
+  spec.add_development_dependency 'pry'
   spec.add_development_dependency 'rack'
+  spec.add_development_dependency 'rake', '~> 13.0'
+  spec.add_development_dependency 'rspec'
+  spec.add_development_dependency 'rubocop'
   spec.add_development_dependency 'simplecov', '~> 0.18.5'
+  spec.add_development_dependency 'sinatra', '>= 1.4.7', '< 3'
 end
diff --git a/spec/fixtures/event_webhook.rb b/spec/fixtures/event_webhook.rb
index 05236df4..9195129c 100644
--- a/spec/fixtures/event_webhook.rb
+++ b/spec/fixtures/event_webhook.rb
@@ -2,21 +2,21 @@
 
 module Fixtures
   module EventWebhook
-    PUBLIC_KEY = 'MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE83T4O/n84iotIvIW4mdBgQ/7dAfSmpqIM8kF9mN1flpVKS3GRqe62gw+2fNNRaINXvVpiglSI8eNEc6wEA3F+g=='
-    FAILING_PUBLIC_KEY = 'MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEqTxd43gyp8IOEto2LdIfjRQrIbsd4SXZkLW6jDutdhXSJCWHw8REntlo7aNDthvj+y7GjUuFDb/R1NGe1OPzpA=='
-    SIGNATURE = 'MEUCIGHQVtGj+Y3LkG9fLcxf3qfI10QysgDWmMOVmxG0u6ZUAiEAyBiXDWzM+uOe5W0JuG+luQAbPIqHh89M15TluLtEZtM='
-    FAILING_SIGNATURE = 'MEUCIQCtIHJeH93Y+qpYeWrySphQgpNGNr/U+UyUlBkU6n7RAwIgJTz2C+8a8xonZGi6BpSzoQsbVRamr2nlxFDWYNH3j/0='
-    TIMESTAMP = '1600112502'
+    PUBLIC_KEY = 'MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE83T4O/n84iotIvIW4mdBgQ/7dAfSmpqIM8kF9mN1flpVKS3GRqe62gw+2fNNRaINXvVpiglSI8eNEc6wEA3F+g=='.freeze
+    FAILING_PUBLIC_KEY = 'MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEqTxd43gyp8IOEto2LdIfjRQrIbsd4SXZkLW6jDutdhXSJCWHw8REntlo7aNDthvj+y7GjUuFDb/R1NGe1OPzpA=='.freeze
+    SIGNATURE = 'MEUCIGHQVtGj+Y3LkG9fLcxf3qfI10QysgDWmMOVmxG0u6ZUAiEAyBiXDWzM+uOe5W0JuG+luQAbPIqHh89M15TluLtEZtM='.freeze
+    FAILING_SIGNATURE = 'MEUCIQCtIHJeH93Y+qpYeWrySphQgpNGNr/U+UyUlBkU6n7RAwIgJTz2C+8a8xonZGi6BpSzoQsbVRamr2nlxFDWYNH3j/0='.freeze
+    TIMESTAMP = '1600112502'.freeze
     PAYLOAD = [
-        {
-            email: 'hello@world.com',
-            event: 'dropped',
-            reason: 'Bounced Address',
-            sg_event_id: 'ZHJvcC0xMDk5NDkxOS1MUnpYbF9OSFN0T0doUTRrb2ZTbV9BLTA',
-            sg_message_id: 'LRzXl_NHStOGhQ4kofSm_A.filterdrecv-p3mdw1-756b745b58-kmzbl-18-5F5FC76C-9.0',
-            'smtp-id': '<LRzXl_NHStOGhQ4kofSm_A@ismtpd0039p1iad1.sendgrid.net>',
-            timestamp: 1600112492,
-        }
+      {
+        email: 'hello@world.com',
+        event: 'dropped',
+        reason: 'Bounced Address',
+        sg_event_id: 'ZHJvcC0xMDk5NDkxOS1MUnpYbF9OSFN0T0doUTRrb2ZTbV9BLTA',
+        sg_message_id: 'LRzXl_NHStOGhQ4kofSm_A.filterdrecv-p3mdw1-756b745b58-kmzbl-18-5F5FC76C-9.0',
+        'smtp-id': '<LRzXl_NHStOGhQ4kofSm_A@ismtpd0039p1iad1.sendgrid.net>',
+        timestamp: 1_600_112_492
+      }
     ].to_json + "\r\n" # Be sure to include the trailing carriage return and newline!
   end
 end
diff --git a/spec/rack/sendgrid_webhook_verification_spec.rb b/spec/rack/sendgrid_webhook_verification_spec.rb
index 4cd45604..11bfd0b1 100644
--- a/spec/rack/sendgrid_webhook_verification_spec.rb
+++ b/spec/rack/sendgrid_webhook_verification_spec.rb
@@ -12,19 +12,19 @@
     describe 'new' do
       it 'should initialize with an app, public key and a path' do
         expect do
-          Rack::SendGridWebhookVerification.new(@app, 'ABC', /\/email/)
+          Rack::SendGridWebhookVerification.new(@app, 'ABC', %r{/email})
         end.not_to raise_error
       end
 
       it 'should initialize with an app, public key and paths' do
         expect do
-          Rack::SendGridWebhookVerification.new(@app, 'ABC', /\/email/, /\/event/)
+          Rack::SendGridWebhookVerification.new(@app, 'ABC', %r{/email}, %r{/event})
         end.not_to raise_error
       end
     end
 
     describe 'calling against one path' do
-      let(:middleware) { Rack::SendGridWebhookVerification.new(@app, public_key, /\/email/) }
+      let(:middleware) { Rack::SendGridWebhookVerification.new(@app, public_key, %r{/email}) }
 
       it "should not intercept when the path doesn't match" do
         expect(SendGrid::EventWebhook).to_not receive(:new)
@@ -81,7 +81,7 @@
     end
 
     describe 'calling with multiple paths' do
-      let(:middleware) { Rack::SendGridWebhookVerification.new(@app, public_key, /\/email/, /\/events/) }
+      let(:middleware) { Rack::SendGridWebhookVerification.new(@app, public_key, %r{/email}, %r{/events}) }
 
       it "should not intercept when the path doesn't match" do
         expect(SendGrid::EventWebhook).to_not receive(:new)
diff --git a/spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb b/spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb
index 32d39950..1d928e82 100644
--- a/spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb
+++ b/spec/sendgrid/helpers/eventwebhook/eventwebhook_spec.rb
@@ -6,77 +6,79 @@
     it 'verifies a valid signature' do
       unless skip_jruby
         expect(verify(
-          Fixtures::EventWebhook::PUBLIC_KEY,
-          Fixtures::EventWebhook::PAYLOAD,
-          Fixtures::EventWebhook::SIGNATURE,
-          Fixtures::EventWebhook::TIMESTAMP
-        )).to be true
+                 Fixtures::EventWebhook::PUBLIC_KEY,
+                 Fixtures::EventWebhook::PAYLOAD,
+                 Fixtures::EventWebhook::SIGNATURE,
+                 Fixtures::EventWebhook::TIMESTAMP
+               )).to be true
       end
     end
 
     it 'rejects a bad key' do
       unless skip_jruby
         expect(verify(
-          Fixtures::EventWebhook::FAILING_PUBLIC_KEY,
-          Fixtures::EventWebhook::PAYLOAD,
-          Fixtures::EventWebhook::SIGNATURE,
-          Fixtures::EventWebhook::TIMESTAMP
-        )).to be false
+                 Fixtures::EventWebhook::FAILING_PUBLIC_KEY,
+                 Fixtures::EventWebhook::PAYLOAD,
+                 Fixtures::EventWebhook::SIGNATURE,
+                 Fixtures::EventWebhook::TIMESTAMP
+               )).to be false
       end
     end
 
     it 'rejects a bad payload' do
       unless skip_jruby
         expect(verify(
-          Fixtures::EventWebhook::PUBLIC_KEY,
-          'payload',
-          Fixtures::EventWebhook::SIGNATURE,
-          Fixtures::EventWebhook::TIMESTAMP
-        )).to be false
+                 Fixtures::EventWebhook::PUBLIC_KEY,
+                 'payload',
+                 Fixtures::EventWebhook::SIGNATURE,
+                 Fixtures::EventWebhook::TIMESTAMP
+               )).to be false
       end
     end
 
     it 'rejects a bad signature' do
       unless skip_jruby
         expect(verify(
-          Fixtures::EventWebhook::PUBLIC_KEY,
-          Fixtures::EventWebhook::PAYLOAD,
-          Fixtures::EventWebhook::FAILING_SIGNATURE,
-          Fixtures::EventWebhook::TIMESTAMP
-        )).to be false
+                 Fixtures::EventWebhook::PUBLIC_KEY,
+                 Fixtures::EventWebhook::PAYLOAD,
+                 Fixtures::EventWebhook::FAILING_SIGNATURE,
+                 Fixtures::EventWebhook::TIMESTAMP
+               )).to be false
       end
     end
 
     it 'rejects a bad timestamp' do
       unless skip_jruby
         expect(verify(
-          Fixtures::EventWebhook::PUBLIC_KEY,
-          Fixtures::EventWebhook::PAYLOAD,
-          Fixtures::EventWebhook::SIGNATURE,
-          'timestamp'
-        )).to be false
+                 Fixtures::EventWebhook::PUBLIC_KEY,
+                 Fixtures::EventWebhook::PAYLOAD,
+                 Fixtures::EventWebhook::SIGNATURE,
+                 'timestamp'
+               )).to be false
       end
     end
 
     it 'rejects a missing signature' do
       unless skip_jruby
         expect(verify(
-          Fixtures::EventWebhook::PUBLIC_KEY,
-          Fixtures::EventWebhook::PAYLOAD,
-          nil,
-          Fixtures::EventWebhook::TIMESTAMP
-        )).to be false
+                 Fixtures::EventWebhook::PUBLIC_KEY,
+                 Fixtures::EventWebhook::PAYLOAD,
+                 nil,
+                 Fixtures::EventWebhook::TIMESTAMP
+               )).to be false
       end
     end
 
     it 'throws an error when using jruby' do
       if skip_jruby
-        expect{ verify(
-          Fixtures::EventWebhook::PUBLIC_KEY,
-          Fixtures::EventWebhook::PAYLOAD,
-          Fixtures::EventWebhook::SIGNATURE, 
-          Fixtures::EventWebhook::TIMESTAMP
-        )}.to raise_error(SendGrid::EventWebhook::NotSupportedError)
+        expect do
+          verify(
+            Fixtures::EventWebhook::PUBLIC_KEY,
+            Fixtures::EventWebhook::PAYLOAD,
+            Fixtures::EventWebhook::SIGNATURE,
+            Fixtures::EventWebhook::TIMESTAMP
+          )
+        end .to raise_error(SendGrid::EventWebhook::NotSupportedError)
       end
     end
   end
diff --git a/spec/sendgrid/helpers/settings/settings_spec.rb b/spec/sendgrid/helpers/settings/settings_spec.rb
index 543ebc89..640be2a3 100644
--- a/spec/sendgrid/helpers/settings/settings_spec.rb
+++ b/spec/sendgrid/helpers/settings/settings_spec.rb
@@ -18,7 +18,7 @@
 
   describe '.update_bcc' do
     it 'updates bcc' do
-      bcc_response = settings.update_bcc(enabled: true, email: "email@example.com")
+      bcc_response = settings.update_bcc(enabled: true, email: 'email@example.com')
       expect(bcc_response).to be_a SendGrid::Response
     end
   end
diff --git a/spec/sendgrid/helpers/stats/email_stats_spec.rb b/spec/sendgrid/helpers/stats/email_stats_spec.rb
index 8c8cba0f..e9c6c633 100644
--- a/spec/sendgrid/helpers/stats/email_stats_spec.rb
+++ b/spec/sendgrid/helpers/stats/email_stats_spec.rb
@@ -7,26 +7,26 @@
 
   let(:sample_response) do
     [{
-      "date" => "2017-10-01",
-      "stats" => [
-        { "metrics" =>
+      'date' => '2017-10-01',
+      'stats' => [
+        { 'metrics' =>
           {
-            "blocks" => 101,
-            "bounce_drops" => 102,
-            "bounces" => 103,
-            "clicks" => 104,
-            "deferred" => 105,
-            "delivered" => 106,
-            "invalid_emails" => 107,
-            "opens" => 108,
-            "processed" => 109,
-            "requests" => 110,
-            "spam_report_drops" => 111,
-            "spam_reports" => 112,
-            "unique_clicks" => 113,
-            "unique_opens" => 114,
-            "unsubscribe_drops" => 115,
-            "unsubscribes" => 116
+            'blocks' => 101,
+            'bounce_drops' => 102,
+            'bounces' => 103,
+            'clicks' => 104,
+            'deferred' => 105,
+            'delivered' => 106,
+            'invalid_emails' => 107,
+            'opens' => 108,
+            'processed' => 109,
+            'requests' => 110,
+            'spam_report_drops' => 111,
+            'spam_reports' => 112,
+            'unique_clicks' => 113,
+            'unique_opens' => 114,
+            'unsubscribe_drops' => 115,
+            'unsubscribes' => 116
           } }
       ]
     }]
@@ -34,9 +34,9 @@
 
   let(:error_response) do
     {
-      "errors" => [
+      'errors' => [
         {
-          "message" => "end_date should be a YYYY-MM-DD formatted date"
+          'message' => 'end_date should be a YYYY-MM-DD formatted date'
         }
       ]
     }
diff --git a/spec/sendgrid/helpers/stats/metrics_spec.rb b/spec/sendgrid/helpers/stats/metrics_spec.rb
index fb53b7e8..b7a121b4 100644
--- a/spec/sendgrid/helpers/stats/metrics_spec.rb
+++ b/spec/sendgrid/helpers/stats/metrics_spec.rb
@@ -3,23 +3,23 @@
 describe SendGrid::Metrics do
   let(:params) do
     {
-      "date" => "2017-10-01",
-      "blocks" => 101,
-      "bounce_drops" => 102,
-      "bounces" => 103,
-      "clicks" => 104,
-      "deferred" => 105,
-      "delivered" => 106,
-      "invalid_emails" => 107,
-      "opens" => 108,
-      "processed" => 109,
-      "requests" => 110,
-      "spam_report_drops" => 111,
-      "spam_reports" => 112,
-      "unique_clicks" => 113,
-      "unique_opens" => 114,
-      "unsubscribe_drops" => 115,
-      "unsubscribes" => 116
+      'date' => '2017-10-01',
+      'blocks' => 101,
+      'bounce_drops' => 102,
+      'bounces' => 103,
+      'clicks' => 104,
+      'deferred' => 105,
+      'delivered' => 106,
+      'invalid_emails' => 107,
+      'opens' => 108,
+      'processed' => 109,
+      'requests' => 110,
+      'spam_report_drops' => 111,
+      'spam_reports' => 112,
+      'unique_clicks' => 113,
+      'unique_opens' => 114,
+      'unsubscribe_drops' => 115,
+      'unsubscribes' => 116
     }
   end
 
diff --git a/spec/sendgrid/helpers/stats/stats_response_spec.rb b/spec/sendgrid/helpers/stats/stats_response_spec.rb
index d6a3d30d..c3b99cbe 100644
--- a/spec/sendgrid/helpers/stats/stats_response_spec.rb
+++ b/spec/sendgrid/helpers/stats/stats_response_spec.rb
@@ -3,26 +3,26 @@
 describe SendGrid::StatsResponse do
   let(:params) do
     [{
-      "date" => "2017-10-01",
-      "stats" => [
-        { "metrics" =>
+      'date' => '2017-10-01',
+      'stats' => [
+        { 'metrics' =>
           {
-            "blocks" => 101,
-            "bounce_drops" => 102,
-            "bounces" => 103,
-            "clicks" => 104,
-            "deferred" => 105,
-            "delivered" => 106,
-            "invalid_emails" => 107,
-            "opens" => 108,
-            "processed" => 109,
-            "requests" => 110,
-            "spam_report_drops" => 111,
-            "spam_reports" => 112,
-            "unique_clicks" => 113,
-            "unique_opens" => 114,
-            "unsubscribe_drops" => 115,
-            "unsubscribes" => 116
+            'blocks' => 101,
+            'bounce_drops' => 102,
+            'bounces' => 103,
+            'clicks' => 104,
+            'deferred' => 105,
+            'delivered' => 106,
+            'invalid_emails' => 107,
+            'opens' => 108,
+            'processed' => 109,
+            'requests' => 110,
+            'spam_report_drops' => 111,
+            'spam_reports' => 112,
+            'unique_clicks' => 113,
+            'unique_opens' => 114,
+            'unsubscribe_drops' => 115,
+            'unsubscribes' => 116
           } }
       ]
     }]
@@ -50,9 +50,9 @@
   context 'errors' do
     let(:error_params) do
       {
-        "errors" => [
+        'errors' => [
           {
-            "message" => "end_date should be a YYYY-MM-DD formatted date"
+            'message' => 'end_date should be a YYYY-MM-DD formatted date'
           }
         ]
       }
diff --git a/test/sendgrid/helpers/mail/test_attachment.rb b/test/sendgrid/helpers/mail/test_attachment.rb
index f66ebb16..0fecca00 100644
--- a/test/sendgrid/helpers/mail/test_attachment.rb
+++ b/test/sendgrid/helpers/mail/test_attachment.rb
@@ -1,19 +1,17 @@
-# coding: utf-8
 require_relative "../../../../lib/sendgrid/helpers/mail/attachment"
 include SendGrid
 require "json"
 require "minitest/autorun"
 
 class TestAttachment < Minitest::Test
-  SAMPLE_INPUT = """Es blüht so grün wie Blüten blüh'n im Frühling
+  SAMPLE_INPUT = "Es blüht so grün wie Blüten blüh'n im Frühling
 Es blüht so grün wie Blüten blüh'n im Frühling
 Es blüht so grün wie Blüten blüh'n im Frühling
 Es blüht so grün wie Blüten blüh'n im Frühling
 Es blüht so grün wie Blüten blüh'n im Frühling
-""".force_encoding('UTF-8').encode
-  
-  def setup
-  end
+".force_encoding('UTF-8').encode
+
+  def setup; end
 
   def test_io_enocding
     attachment = Attachment.new
diff --git a/test/sendgrid/helpers/mail/test_email.rb b/test/sendgrid/helpers/mail/test_email.rb
index 182c0d03..28f5c2ce 100644
--- a/test/sendgrid/helpers/mail/test_email.rb
+++ b/test/sendgrid/helpers/mail/test_email.rb
@@ -5,27 +5,27 @@ class TestEmail < Minitest::Test
   include SendGrid
 
   def test_split_email_full_email
-    @email = Email.new(email: "Example User <test1@example.com>")
+    @email = Email.new(email: 'Example User <test1@example.com>')
     expected_json = {
-      "email" => "test1@example.com",
-      "name" => "Example User"
+      'email' => 'test1@example.com',
+      'name' => 'Example User'
     }
     assert_equal @email.to_json, expected_json
   end
 
   def test_split_email_only_email
-    @email = Email.new(email: "test1@example.com")
+    @email = Email.new(email: 'test1@example.com')
     expected_json = {
-      "email" => "test1@example.com"
+      'email' => 'test1@example.com'
     }
     assert_equal @email.to_json, expected_json
   end
 
   def test_split_email_name_and_email
-    @email = Email.new(name: "Example User", email: "test1@example.com")
+    @email = Email.new(name: 'Example User', email: 'test1@example.com')
     expected_json = {
-      "email" => "test1@example.com",
-      "name" => "Example User"
+      'email' => 'test1@example.com',
+      'name' => 'Example User'
     }
     assert_equal @email.to_json, expected_json
   end
diff --git a/test/sendgrid/helpers/mail/test_mail.rb b/test/sendgrid/helpers/mail/test_mail.rb
index e63b2d4a..ec44153a 100644
--- a/test/sendgrid/helpers/mail/test_mail.rb
+++ b/test/sendgrid/helpers/mail/test_mail.rb
@@ -1,7 +1,7 @@
-require_relative "../../../../lib/sendgrid/helpers/mail/mail"
-require_relative "../../../../lib/sendgrid/sendgrid"
+require_relative '../../../../lib/sendgrid/helpers/mail/mail'
+require_relative '../../../../lib/sendgrid/sendgrid'
 include SendGrid
-require "json"
+require 'json'
 require 'minitest/autorun'
 
 class TestMail < Minitest::Test
@@ -19,100 +19,100 @@ def test_hello_world
 
   def test_kitchen_sink
     mail = SendGrid::Mail.new
-    mail.from = Email.new(email: "test@example.com")
-    mail.subject = "Hello World from the Twilio SendGrid Ruby Library"
+    mail.from = Email.new(email: 'test@example.com')
+    mail.subject = 'Hello World from the Twilio SendGrid Ruby Library'
     personalization = Personalization.new
-    personalization.add_to(Email.new(email: "test@example.com", name: "Example User"))
-    personalization.add_to(Email.new(email: "test@example.com", name: "Example User"))
-    personalization.add_cc(Email.new(email: "test@example.com", name: "Example User"))
-    personalization.add_cc(Email.new(email: "test@example.com", name: "Example User"))
-    personalization.add_bcc(Email.new(email: "test@example.com", name: "Example User"))
-    personalization.add_bcc(Email.new(email: "test@example.com", name: "Example User"))
-    personalization.subject = "Hello World from the Personalized Twilio SendGrid Ruby Library"
-    personalization.add_header(Header.new(key: "X-Test", value: "True"))
-    personalization.add_header(Header.new(key: "X-Mock", value: "False"))
-    personalization.add_substitution(Substitution.new(key: "%name%", value: "Example User"))
-    personalization.add_substitution(Substitution.new(key: "%city%", value: "Denver"))
-    personalization.add_custom_arg(CustomArg.new(key: "user_id", value: "343"))
-    personalization.add_custom_arg(CustomArg.new(key: "type", value: "marketing"))
-    personalization.send_at = 1443636843
+    personalization.add_to(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization.add_to(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization.add_cc(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization.add_cc(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization.add_bcc(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization.add_bcc(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization.subject = 'Hello World from the Personalized Twilio SendGrid Ruby Library'
+    personalization.add_header(Header.new(key: 'X-Test', value: 'True'))
+    personalization.add_header(Header.new(key: 'X-Mock', value: 'False'))
+    personalization.add_substitution(Substitution.new(key: '%name%', value: 'Example User'))
+    personalization.add_substitution(Substitution.new(key: '%city%', value: 'Denver'))
+    personalization.add_custom_arg(CustomArg.new(key: 'user_id', value: '343'))
+    personalization.add_custom_arg(CustomArg.new(key: 'type', value: 'marketing'))
+    personalization.send_at = 1_443_636_843
     mail.add_personalization(personalization)
 
     personalization2 = Personalization.new
-    personalization2.add_to(Email.new(email: "test@example.com", name: "Example User"))
-    personalization2.add_to(Email.new(email: "test@example.com", name: "Example User"))
-    personalization2.add_cc(Email.new(email: "test@example.com", name: "Example User"))
-    personalization2.add_cc(Email.new(email: "test@example.com", name: "Example User"))
-    personalization2.add_bcc(Email.new(email: "test@example.com", name: "Example User"))
-    personalization2.add_bcc(Email.new(email: "test@example.com", name: "Example User"))
-    personalization2.subject = "Hello World from the Personalized Twilio SendGrid Ruby Library"
-    personalization2.add_header(Header.new(key: "X-Test", value: "True"))
-    personalization2.add_header(Header.new(key: "X-Mock", value: "False"))
-    personalization2.add_substitution(Substitution.new(key: "%name%", value: "Example User"))
-    personalization2.add_substitution(Substitution.new(key: "%city%", value: "Denver"))
-    personalization2.add_custom_arg(CustomArg.new(key: "user_id", value: "343"))
-    personalization2.add_custom_arg(CustomArg.new(key: "type", value: "marketing"))
-    personalization2.send_at = 1443636843
+    personalization2.add_to(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization2.add_to(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization2.add_cc(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization2.add_cc(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization2.add_bcc(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization2.add_bcc(Email.new(email: 'test@example.com', name: 'Example User'))
+    personalization2.subject = 'Hello World from the Personalized Twilio SendGrid Ruby Library'
+    personalization2.add_header(Header.new(key: 'X-Test', value: 'True'))
+    personalization2.add_header(Header.new(key: 'X-Mock', value: 'False'))
+    personalization2.add_substitution(Substitution.new(key: '%name%', value: 'Example User'))
+    personalization2.add_substitution(Substitution.new(key: '%city%', value: 'Denver'))
+    personalization2.add_custom_arg(CustomArg.new(key: 'user_id', value: '343'))
+    personalization2.add_custom_arg(CustomArg.new(key: 'type', value: 'marketing'))
+    personalization2.send_at = 1_443_636_843
     mail.add_personalization(personalization2)
 
-    mail.add_content(Content.new(type: "text/plain", value: "some text here"))
-    mail.add_content(Content.new(type: "text/html", value: "<html><body>some text here</body></html>"))
+    mail.add_content(Content.new(type: 'text/plain', value: 'some text here'))
+    mail.add_content(Content.new(type: 'text/html', value: '<html><body>some text here</body></html>'))
 
     attachment = Attachment.new
-    attachment.content = "TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2NpbmcgZWxpdC4gQ3JhcyBwdW12"
-    attachment.type = "application/pdf"
-    attachment.filename = "balance_001.pdf"
-    attachment.disposition = "attachment"
-    attachment.content_id = "Balance Sheet"
+    attachment.content = 'TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2NpbmcgZWxpdC4gQ3JhcyBwdW12'
+    attachment.type = 'application/pdf'
+    attachment.filename = 'balance_001.pdf'
+    attachment.disposition = 'attachment'
+    attachment.content_id = 'Balance Sheet'
 
     mail.add_attachment(attachment)
 
     attachment2 = Attachment.new
-    attachment2.content = "BwdW"
-    attachment2.type = "image/png"
-    attachment2.filename = "banner.png"
-    attachment2.disposition = "inline"
-    attachment2.content_id = "Banner"
+    attachment2.content = 'BwdW'
+    attachment2.type = 'image/png'
+    attachment2.filename = 'banner.png'
+    attachment2.disposition = 'inline'
+    attachment2.content_id = 'Banner'
     mail.add_attachment(attachment2)
 
-    mail.template_id = "13b8f94f-bcae-4ec6-b752-70d6cb59f932"
+    mail.template_id = '13b8f94f-bcae-4ec6-b752-70d6cb59f932'
 
-    mail.add_section(Section.new(key: "%section1%", value: "Substitution Text for Section 1"))
-    mail.add_section(Section.new(key: "%section2%", value: "Substitution Text for Section 2"))
+    mail.add_section(Section.new(key: '%section1%', value: 'Substitution Text for Section 1'))
+    mail.add_section(Section.new(key: '%section2%', value: 'Substitution Text for Section 2'))
 
-    mail.add_header(Header.new(key: "X-Test3", value: "test3"))
-    mail.add_header(Header.new(key: "X-Test4", value: "test4"))
+    mail.add_header(Header.new(key: 'X-Test3', value: 'test3'))
+    mail.add_header(Header.new(key: 'X-Test4', value: 'test4'))
 
-    mail.add_category(Category.new(name: "May"))
-    mail.add_category(Category.new(name: "2016"))
+    mail.add_category(Category.new(name: 'May'))
+    mail.add_category(Category.new(name: '2016'))
 
-    mail.add_custom_arg(CustomArg.new(key: "campaign", value: "welcome"))
-    mail.add_custom_arg(CustomArg.new(key: "weekday", value: "morning"))
+    mail.add_custom_arg(CustomArg.new(key: 'campaign', value: 'welcome'))
+    mail.add_custom_arg(CustomArg.new(key: 'weekday', value: 'morning'))
 
-    mail.send_at = 1443636842
+    mail.send_at = 1_443_636_842
 
-    mail.batch_id = "sendgrid_batch_id"
+    mail.batch_id = 'sendgrid_batch_id'
 
     mail.asm = ASM.new(group_id: 99, groups_to_display: [4, 5, 6, 7, 8])
 
-    mail.ip_pool_name = "23"
+    mail.ip_pool_name = '23'
 
     mail_settings = MailSettings.new
-    mail_settings.bcc = BccSettings.new(enable: true, email: "test@example.com")
+    mail_settings.bcc = BccSettings.new(enable: true, email: 'test@example.com')
     mail_settings.bypass_list_management = BypassListManagement.new(enable: true)
-    mail_settings.footer = Footer.new(enable: true, text: "Footer Text", html: "<html><body>Footer Text</body></html>")
+    mail_settings.footer = Footer.new(enable: true, text: 'Footer Text', html: '<html><body>Footer Text</body></html>')
     mail_settings.sandbox_mode = SandBoxMode.new(enable: true)
-    mail_settings.spam_check = SpamCheck.new(enable: true, threshold: 1, post_to_url: "https://spamcatcher.sendgrid.com")
+    mail_settings.spam_check = SpamCheck.new(enable: true, threshold: 1, post_to_url: 'https://spamcatcher.sendgrid.com')
     mail.mail_settings = mail_settings
 
     tracking_settings = TrackingSettings.new
     tracking_settings.click_tracking = ClickTracking.new(enable: false, enable_text: false)
-    tracking_settings.open_tracking = OpenTracking.new(enable: true, substitution_tag: "Optional tag to replace with the open image in the body of the message")
-    tracking_settings.subscription_tracking = SubscriptionTracking.new(enable: true, text: "text to insert into the text/plain portion of the message", html: "html to insert into the text/html portion of the message", substitution_tag: "Optional tag to replace with the open image in the body of the message")
-    tracking_settings.ganalytics = Ganalytics.new(enable: true, utm_source: "some source", utm_medium: "some medium", utm_term: "some term", utm_content: "some content", utm_campaign: "some campaign")
+    tracking_settings.open_tracking = OpenTracking.new(enable: true, substitution_tag: 'Optional tag to replace with the open image in the body of the message')
+    tracking_settings.subscription_tracking = SubscriptionTracking.new(enable: true, text: 'text to insert into the text/plain portion of the message', html: 'html to insert into the text/html portion of the message', substitution_tag: 'Optional tag to replace with the open image in the body of the message')
+    tracking_settings.ganalytics = Ganalytics.new(enable: true, utm_source: 'some source', utm_medium: 'some medium', utm_term: 'some term', utm_content: 'some content', utm_campaign: 'some campaign')
     mail.tracking_settings = tracking_settings
 
-    mail.reply_to = Email.new(email: "test@example.com")
+    mail.reply_to = Email.new(email: 'test@example.com')
 
     assert_equal(mail.to_json, JSON.parse('{"asm":{"group_id":99,"groups_to_display":[4,5,6,7,8]},"attachments":[{"content":"TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2NpbmcgZWxpdC4gQ3JhcyBwdW12","content_id":"Balance Sheet","disposition":"attachment","filename":"balance_001.pdf","type":"application/pdf"},{"content":"BwdW","content_id":"Banner","disposition":"inline","filename":"banner.png","type":"image/png"}],"batch_id":"sendgrid_batch_id","categories":["May","2016"],"content":[{"type":"text/plain","value":"some text here"},{"type":"text/html","value":"<html><body>some text here</body></html>"}],"custom_args":{"campaign":"welcome","weekday":"morning"},"from":{"email":"test@example.com"},"headers":{"X-Test3":"test3","X-Test4":"test4"},"ip_pool_name":"23","mail_settings":{"bcc":{"email":"test@example.com","enable":true},"bypass_list_management":{"enable":true},"footer":{"enable":true,"html":"<html><body>Footer Text</body></html>","text":"Footer Text"},"sandbox_mode":{"enable":true},"spam_check":{"enable":true,"post_to_url":"https://spamcatcher.sendgrid.com","threshold":1}},"personalizations":[{"bcc":[{"email":"test@example.com","name":"Example User"},{"email":"test@example.com","name":"Example User"}],"cc":[{"email":"test@example.com","name":"Example User"},{"email":"test@example.com","name":"Example User"}],"custom_args":{"type":"marketing","user_id":"343"},"headers":{"X-Mock":"False","X-Test":"True"},"send_at":1443636843,"subject":"Hello World from the Personalized Twilio SendGrid Ruby Library","substitutions":{"%city%":"Denver","%name%":"Example User"},"to":[{"email":"test@example.com","name":"Example User"},{"email":"test@example.com","name":"Example User"}]},{"bcc":[{"email":"test@example.com","name":"Example User"},{"email":"test@example.com","name":"Example User"}],"cc":[{"email":"test@example.com","name":"Example User"},{"email":"test@example.com","name":"Example User"}],"custom_args":{"type":"marketing","user_id":"343"},"headers":{"X-Mock":"False","X-Test":"True"},"send_at":1443636843,"subject":"Hello World from the Personalized Twilio SendGrid Ruby Library","substitutions":{"%city%":"Denver","%name%":"Example User"},"to":[{"email":"test@example.com","name":"Example User"},{"email":"test@example.com","name":"Example User"}]}],"reply_to":{"email":"test@example.com"},"sections":{"%section1%":"Substitution Text for Section 1","%section2%":"Substitution Text for Section 2"},"send_at":1443636842,"subject":"Hello World from the Twilio SendGrid Ruby Library","template_id":"13b8f94f-bcae-4ec6-b752-70d6cb59f932","tracking_settings":{"click_tracking":{"enable":false,"enable_text":false},"ganalytics":{"enable":true,"utm_campaign":"some campaign","utm_content":"some content","utm_medium":"some medium","utm_source":"some source","utm_term":"some term"},"open_tracking":{"enable":true,"substitution_tag":"Optional tag to replace with the open image in the body of the message"},"subscription_tracking":{"enable":true,"html":"html to insert into the text/html portion of the message","substitution_tag":"Optional tag to replace with the open image in the body of the message","text":"text to insert into the text/plain portion of the message"}}}'))
   end
@@ -153,16 +153,16 @@ def test_add_section
     mail = SendGrid::Mail.new
     mail.add_section(Section.new(key: '%section1%', value: 'Substitution Text for Section 1'))
     expected_json = {
-      "sections" => {
-        "%section1%" => "Substitution Text for Section 1"
+      'sections' => {
+        '%section1%' => 'Substitution Text for Section 1'
       }
     }
     assert_equal mail.to_json, expected_json
     mail.add_section(Section.new(key: '%section2%', value: 'Substitution Text for Section 2'))
     expected_json = {
-      "sections" => {
-        "%section1%" => "Substitution Text for Section 1",
-        "%section2%" => "Substitution Text for Section 2"
+      'sections' => {
+        '%section1%' => 'Substitution Text for Section 1',
+        '%section2%' => 'Substitution Text for Section 2'
       }
     }
     assert_equal mail.to_json, expected_json
@@ -172,16 +172,16 @@ def test_add_header
     mail = SendGrid::Mail.new
     mail.add_header(Header.new(key: 'X-Test3', value: 'test3'))
     expected_json = {
-      "headers" => {
-        "X-Test3" => "test3"
+      'headers' => {
+        'X-Test3' => 'test3'
       }
     }
     assert_equal mail.to_json, expected_json
     mail.add_header(Header.new(key: 'X-Test4', value: 'test4'))
     expected_json = {
-      "headers" => {
-        "X-Test3" => "test3",
-        "X-Test4" => "test4"
+      'headers' => {
+        'X-Test3' => 'test3',
+        'X-Test4' => 'test4'
       }
     }
     assert_equal mail.to_json, expected_json
@@ -191,16 +191,16 @@ def test_add_custom_arg
     mail = SendGrid::Mail.new
     mail.add_custom_arg(CustomArg.new(key: 'campaign 1', value: 'welcome 1'))
     expected_json = {
-      "custom_args" => {
-        "campaign 1" => "welcome 1"
+      'custom_args' => {
+        'campaign 1' => 'welcome 1'
       }
     }
     assert_equal mail.to_json, expected_json
     mail.add_custom_arg(CustomArg.new(key: 'campaign 2', value: 'welcome 2'))
     expected_json = {
-      "custom_args" => {
-        "campaign 1" => "welcome 1",
-        "campaign 2" => "welcome 2"
+      'custom_args' => {
+        'campaign 1' => 'welcome 1',
+        'campaign 2' => 'welcome 2'
       }
     }
     assert_equal mail.to_json, expected_json
@@ -208,14 +208,14 @@ def test_add_custom_arg
 
   def test_add_non_string_custom_arg
     mail = Mail.new
-    mail.add_custom_arg(CustomArg.new(key: "Integer", value: 1))
-    mail.add_custom_arg(CustomArg.new(key: "Array", value: [1, "a", true]))
-    mail.add_custom_arg(CustomArg.new(key: "Hash", value: { "a" => 1, "b" => 2 }))
+    mail.add_custom_arg(CustomArg.new(key: 'Integer', value: 1))
+    mail.add_custom_arg(CustomArg.new(key: 'Array', value: [1, 'a', true]))
+    mail.add_custom_arg(CustomArg.new(key: 'Hash', value: { 'a' => 1, 'b' => 2 }))
     expected_json = {
-      "custom_args" => {
-        "Integer" => "1",
-        "Array" => "[1, \"a\", true]",
-        "Hash" => "{\"a\"=>1, \"b\"=>2}"
+      'custom_args' => {
+        'Integer' => '1',
+        'Array' => '[1, "a", true]',
+        'Hash' => '{"a"=>1, "b"=>2}'
       }
     }
     assert_equal mail.to_json, expected_json
@@ -236,11 +236,9 @@ def test_add_valid_category
 
   def test_add_more_than_1_valid_category
     mail = SendGrid::Mail.new
-    category_1 = Category.new(name: 'foo')
-    category_2 = Category.new(name: 'bar')
-    mail.add_category(category_1)
-    mail.add_category(category_2)
-    assert_equal(['foo', 'bar'], mail.categories)
+    mail.add_category(Category.new(name: 'foo'))
+    mail.add_category(Category.new(name: 'bar'))
+    assert_equal(%w[foo bar], mail.categories)
   end
 
   def test_add_invalid_category
diff --git a/test/sendgrid/helpers/mail/test_personalizations.rb b/test/sendgrid/helpers/mail/test_personalizations.rb
index b6517e86..3b8c0efe 100644
--- a/test/sendgrid/helpers/mail/test_personalizations.rb
+++ b/test/sendgrid/helpers/mail/test_personalizations.rb
@@ -9,14 +9,14 @@ def test_add_to
     @personalization.add_to(Email.new(email: 'test1@example.com', name: 'Example User'))
     @personalization.add_to(Email.new(email: 'test2@example.com', name: 'Example User 2'))
     expected_json = {
-      "to" => [
+      'to' => [
         {
-          "email" => "test1@example.com",
-          "name" => "Example User"
+          'email' => 'test1@example.com',
+          'name' => 'Example User'
         },
         {
-          "email" => "test2@example.com",
-          "name" => "Example User 2"
+          'email' => 'test2@example.com',
+          'name' => 'Example User 2'
         }
       ]
     }
@@ -28,14 +28,14 @@ def test_add_cc
     @personalization.add_cc(Email.new(email: 'test1@example.com', name: 'Example User'))
     @personalization.add_cc(Email.new(email: 'test2@example.com', name: 'Example User 2'))
     expected_json = {
-      "cc" => [
+      'cc' => [
         {
-          "email" => "test1@example.com",
-          "name" => "Example User"
+          'email' => 'test1@example.com',
+          'name' => 'Example User'
         },
         {
-          "email" => "test2@example.com",
-          "name" => "Example User 2"
+          'email' => 'test2@example.com',
+          'name' => 'Example User 2'
         }
       ]
     }
@@ -47,14 +47,14 @@ def test_add_bcc
     @personalization.add_bcc(Email.new(email: 'test1@example.com', name: 'Example User'))
     @personalization.add_bcc(Email.new(email: 'test2@example.com', name: 'Example User 2'))
     expected_json = {
-      "bcc" => [
+      'bcc' => [
         {
-          "email" => "test1@example.com",
-          "name" => "Example User"
+          'email' => 'test1@example.com',
+          'name' => 'Example User'
         },
         {
-          "email" => "test2@example.com",
-          "name" => "Example User 2"
+          'email' => 'test2@example.com',
+          'name' => 'Example User 2'
         }
       ]
     }
@@ -65,16 +65,16 @@ def test_add_header
     @personalization = Personalization.new
     @personalization.add_header(Header.new(key: 'X-Test', value: 'True'))
     expected_json = {
-      "headers" => {
-        "X-Test" => "True"
+      'headers' => {
+        'X-Test' => 'True'
       }
     }
     assert_equal @personalization.to_json, expected_json
     @personalization.add_header(Header.new(key: 'X-Test 1', value: 'False'))
     expected_json = {
-      "headers" => {
-        "X-Test" => "True",
-        "X-Test 1" => "False"
+      'headers' => {
+        'X-Test' => 'True',
+        'X-Test 1' => 'False'
       }
     }
     assert_equal @personalization.to_json, expected_json
@@ -84,16 +84,16 @@ def test_add_substitution
     @personalization = Personalization.new
     @personalization.add_substitution(Substitution.new(key: '%name%', value: 'Example User'))
     expected_json = {
-      "substitutions" => {
-        "%name%" => "Example User"
+      'substitutions' => {
+        '%name%' => 'Example User'
       }
     }
     assert_equal @personalization.to_json, expected_json
     @personalization.add_substitution(Substitution.new(key: '%name 1%', value: 'Example User 1'))
     expected_json = {
-      "substitutions" => {
-        "%name%" => "Example User",
-        "%name 1%" => "Example User 1"
+      'substitutions' => {
+        '%name%' => 'Example User',
+        '%name 1%' => 'Example User 1'
       }
     }
     assert_equal @personalization.to_json, expected_json
@@ -103,16 +103,16 @@ def test_add_custom_arg
     @personalization = Personalization.new
     @personalization.add_custom_arg(CustomArg.new(key: 'user_id', value: '343'))
     expected_json = {
-      "custom_args" => {
-        "user_id" => "343"
+      'custom_args' => {
+        'user_id' => '343'
       }
     }
     assert_equal @personalization.to_json, expected_json
     @personalization.add_custom_arg(CustomArg.new(key: 'city', value: 'denver'))
     expected_json = {
-      "custom_args" => {
-        "user_id" => "343",
-        "city" => "denver"
+      'custom_args' => {
+        'user_id' => '343',
+        'city' => 'denver'
       }
     }
     assert_equal @personalization.to_json, expected_json
@@ -121,13 +121,13 @@ def test_add_custom_arg
   def test_add_dynamic_template_data
     @personalization = Personalization.new
     @personalization.add_dynamic_template_data(
-      "name" => "Example User",
-      "city" => "Denver"
+      'name' => 'Example User',
+      'city' => 'Denver'
     )
     expected_json = {
-      "dynamic_template_data" => {
-        "name" => "Example User",
-        "city" => "Denver"
+      'dynamic_template_data' => {
+        'name' => 'Example User',
+        'city' => 'Denver'
       }
     }
     assert_equal @personalization.to_json, expected_json
diff --git a/test/sendgrid/permissions/test_scopes.rb b/test/sendgrid/permissions/test_scopes.rb
index 2d5eefb3..a299ce25 100644
--- a/test/sendgrid/permissions/test_scopes.rb
+++ b/test/sendgrid/permissions/test_scopes.rb
@@ -2,7 +2,6 @@
 require 'minitest/autorun'
 
 class TestCategory < Minitest::Test
-
   include SendGrid
 
   # usecases
@@ -34,5 +33,4 @@ def test_read_only_and_full_access_from_file
       assert_equal Scope.send("#{endpoint}_full_access_permissions"), @scopes_from_yaml[endpoint].values.flatten
     end
   end
-
 end
diff --git a/test/sendgrid/test_sendgrid-ruby.rb b/test/sendgrid/test_sendgrid-ruby.rb
index e5357174..a0ef10e4 100644
--- a/test/sendgrid/test_sendgrid-ruby.rb
+++ b/test/sendgrid/test_sendgrid-ruby.rb
@@ -6,46 +6,45 @@
 require 'minitest/unit'
 
 class TestAPI < MiniTest::Test
-
-    def setup
-        @sg = SendGrid::API.new(api_key: "SENDGRID_API_KEY")
-    end
-
-    def test_init
-        headers = JSON.parse('
-            {
-                "X-Test": "test"
-            }
-        ')
-        subuser = 'test_user'
-        sg = SendGrid::API.new(api_key: "SENDGRID_API_KEY", host: "https://api.test.com", request_headers: headers, version: "v3", impersonate_subuser: subuser)
-
-        assert_equal("https://api.test.com", sg.host)
-        user_agent       = "sendgrid/#{SendGrid::VERSION};ruby"
-        test_headers = JSON.parse('
-                {
-                    "Authorization": "Bearer SENDGRID_API_KEY",
-                    "Accept": "application/json",
-                    "X-Test": "test",
-                    "User-Agent": "' + user_agent + '",
-                    "On-Behalf-Of": "' + subuser + '"
-                }
-            ')
-        assert_equal(test_headers, sg.request_headers)
-        assert_equal("v3", sg.version)
-        assert_equal(subuser, sg.impersonate_subuser)
-        assert_equal("6.3.4", SendGrid::VERSION)
-        assert_instance_of(SendGrid::Client, sg.client)
-    end
-
-    def test_init_when_impersonate_subuser_is_not_given
-        sg = SendGrid::API.new(api_key: "SENDGRID_API_KEY", host: "https://api.test.com", version: "v3")
-        refute_includes(sg.request_headers, 'On-Behalf-Of')
-    end
-
-    def test_access_settings_activity_get
-        params = JSON.parse('{"limit": 1}')
-        headers = JSON.parse('{"X-Mock": 200}')
+  def setup
+    @sg = SendGrid::API.new(api_key: 'SENDGRID_API_KEY')
+  end
+
+  def test_init
+    headers = JSON.parse('
+          {
+              "X-Test": "test"
+          }
+      ')
+    subuser = 'test_user'
+    sg = SendGrid::API.new(api_key: 'SENDGRID_API_KEY', host: 'https://api.test.com', request_headers: headers, version: 'v3', impersonate_subuser: subuser)
+
+    assert_equal('https://api.test.com', sg.host)
+    user_agent = "sendgrid/#{SendGrid::VERSION};ruby"
+    test_headers = JSON.parse('
+              {
+                  "Authorization": "Bearer SENDGRID_API_KEY",
+                  "Accept": "application/json",
+                  "X-Test": "test",
+                  "User-Agent": "' + user_agent + '",
+                  "On-Behalf-Of": "' + subuser + '"
+              }
+          ')
+    assert_equal(test_headers, sg.request_headers)
+    assert_equal('v3', sg.version)
+    assert_equal(subuser, sg.impersonate_subuser)
+    assert_equal('6.3.4', SendGrid::VERSION)
+    assert_instance_of(SendGrid::Client, sg.client)
+  end
+
+  def test_init_when_impersonate_subuser_is_not_given
+    sg = SendGrid::API.new(api_key: 'SENDGRID_API_KEY', host: 'https://api.test.com', version: 'v3')
+    refute_includes(sg.request_headers, 'On-Behalf-Of')
+  end
+
+  def test_access_settings_activity_get
+    params = JSON.parse('{"limit": 1}')
+    headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.access_settings.activity.get(query_params: params, request_headers: headers)
 
@@ -97,7 +96,7 @@ def test_access_settings_whitelist_delete
   end
 
   def test_access_settings_whitelist__rule_id__get
-    rule_id = "test_url_param"
+    rule_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.access_settings.whitelist._(rule_id).get(request_headers: headers)
@@ -106,7 +105,7 @@ def test_access_settings_whitelist__rule_id__get
   end
 
   def test_access_settings_whitelist__rule_id__delete
-    rule_id = "test_url_param"
+    rule_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.access_settings.whitelist._(rule_id).delete(request_headers: headers)
@@ -139,7 +138,7 @@ def test_alerts__alert_id__patch
     data = JSON.parse('{
 "email_to": "example@example.com"
 }')
-    alert_id = "test_url_param"
+    alert_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.alerts._(alert_id).patch(request_body: data, request_headers: headers)
@@ -148,7 +147,7 @@ def test_alerts__alert_id__patch
   end
 
   def test_alerts__alert_id__get
-    alert_id = "test_url_param"
+    alert_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.alerts._(alert_id).get(request_headers: headers)
@@ -157,7 +156,7 @@ def test_alerts__alert_id__get
   end
 
   def test_alerts__alert_id__delete
-    alert_id = "test_url_param"
+    alert_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.alerts._(alert_id).delete(request_headers: headers)
@@ -199,7 +198,7 @@ def test_api_keys__api_key_id__put
 "user.profile.update"
 ]
 }')
-    api_key_id = "test_url_param"
+    api_key_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.api_keys._(api_key_id).put(request_body: data, request_headers: headers)
@@ -211,7 +210,7 @@ def test_api_keys__api_key_id__patch
     data = JSON.parse('{
 "name": "A New Hope"
 }')
-    api_key_id = "test_url_param"
+    api_key_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.api_keys._(api_key_id).patch(request_body: data, request_headers: headers)
@@ -220,7 +219,7 @@ def test_api_keys__api_key_id__patch
   end
 
   def test_api_keys__api_key_id__get
-    api_key_id = "test_url_param"
+    api_key_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.api_keys._(api_key_id).get(request_headers: headers)
@@ -229,7 +228,7 @@ def test_api_keys__api_key_id__get
   end
 
   def test_api_keys__api_key_id__delete
-    api_key_id = "test_url_param"
+    api_key_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.api_keys._(api_key_id).delete(request_headers: headers)
@@ -265,7 +264,7 @@ def test_asm_groups__group_id__patch
 "id": 103,
 "name": "Item Suggestions"
 }')
-    group_id = "test_url_param"
+    group_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.asm.groups._(group_id).patch(request_body: data, request_headers: headers)
@@ -274,7 +273,7 @@ def test_asm_groups__group_id__patch
   end
 
   def test_asm_groups__group_id__get
-    group_id = "test_url_param"
+    group_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.asm.groups._(group_id).get(request_headers: headers)
@@ -283,7 +282,7 @@ def test_asm_groups__group_id__get
   end
 
   def test_asm_groups__group_id__delete
-    group_id = "test_url_param"
+    group_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.asm.groups._(group_id).delete(request_headers: headers)
@@ -298,7 +297,7 @@ def test_asm_groups__group_id__suppressions_post
 "test2@example.com"
 ]
 }')
-    group_id = "test_url_param"
+    group_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.asm.groups._(group_id).suppressions.post(request_body: data, request_headers: headers)
@@ -307,7 +306,7 @@ def test_asm_groups__group_id__suppressions_post
   end
 
   def test_asm_groups__group_id__suppressions_get
-    group_id = "test_url_param"
+    group_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.asm.groups._(group_id).suppressions.get(request_headers: headers)
@@ -323,7 +322,7 @@ def test_asm_groups__group_id__suppressions_search_post
 "doesnotexists@example.com"
 ]
 }')
-    group_id = "test_url_param"
+    group_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.asm.groups._(group_id).suppressions.search.post(request_body: data, request_headers: headers)
@@ -332,8 +331,8 @@ def test_asm_groups__group_id__suppressions_search_post
   end
 
   def test_asm_groups__group_id__suppressions__email__delete
-    group_id = "test_url_param"
-    email = "test_url_param"
+    group_id = 'test_url_param'
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.asm.groups._(group_id).suppressions._(email).delete(request_headers: headers)
@@ -364,7 +363,7 @@ def test_asm_suppressions_global_post
   end
 
   def test_asm_suppressions_global__email__get
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.asm.suppressions.global._(email).get(request_headers: headers)
@@ -373,7 +372,7 @@ def test_asm_suppressions_global__email__get
   end
 
   def test_asm_suppressions_global__email__delete
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.asm.suppressions.global._(email).delete(request_headers: headers)
@@ -382,7 +381,7 @@ def test_asm_suppressions_global__email__delete
   end
 
   def test_asm_suppressions__email__get
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.asm.suppressions._(email).get(request_headers: headers)
@@ -446,7 +445,7 @@ def test_campaigns__campaign_id__patch
 "subject": "New Products for Summer!",
 "title": "May Newsletter"
 }')
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.campaigns._(campaign_id).patch(request_body: data, request_headers: headers)
@@ -455,7 +454,7 @@ def test_campaigns__campaign_id__patch
   end
 
   def test_campaigns__campaign_id__get
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.campaigns._(campaign_id).get(request_headers: headers)
@@ -464,7 +463,7 @@ def test_campaigns__campaign_id__get
   end
 
   def test_campaigns__campaign_id__delete
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.campaigns._(campaign_id).delete(request_headers: headers)
@@ -476,7 +475,7 @@ def test_campaigns__campaign_id__schedules_patch
     data = JSON.parse('{
 "send_at": 1489451436
 }')
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.campaigns._(campaign_id).schedules.patch(request_body: data, request_headers: headers)
@@ -488,7 +487,7 @@ def test_campaigns__campaign_id__schedules_post
     data = JSON.parse('{
 "send_at": 1489771528
 }')
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.campaigns._(campaign_id).schedules.post(request_body: data, request_headers: headers)
@@ -497,7 +496,7 @@ def test_campaigns__campaign_id__schedules_post
   end
 
   def test_campaigns__campaign_id__schedules_get
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.campaigns._(campaign_id).schedules.get(request_headers: headers)
@@ -506,7 +505,7 @@ def test_campaigns__campaign_id__schedules_get
   end
 
   def test_campaigns__campaign_id__schedules_delete
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.campaigns._(campaign_id).schedules.delete(request_headers: headers)
@@ -515,7 +514,7 @@ def test_campaigns__campaign_id__schedules_delete
   end
 
   def test_campaigns__campaign_id__schedules_now_post
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.campaigns._(campaign_id).schedules.now.post(request_headers: headers)
@@ -527,7 +526,7 @@ def test_campaigns__campaign_id__schedules_test_post
     data = JSON.parse('{
 "to": "your.email@example.com"
 }')
-    campaign_id = "test_url_param"
+    campaign_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.campaigns._(campaign_id).schedules.test.post(request_body: data, request_headers: headers)
@@ -573,7 +572,7 @@ def test_clients_stats_get
 
   def test_clients__client_type__stats_get
     params = JSON.parse('{"aggregated_by": "day", "start_date": "2016-01-01", "end_date": "2016-04-01"}')
-    client_type = "test_url_param"
+    client_type = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.clients._(client_type).stats.get(query_params: params, request_headers: headers)
@@ -602,7 +601,7 @@ def test_contactdb_custom_fields_get
   end
 
   def test_contactdb_custom_fields__custom_field_id__get
-    custom_field_id = "test_url_param"
+    custom_field_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.custom_fields._(custom_field_id).get(request_headers: headers)
@@ -611,7 +610,7 @@ def test_contactdb_custom_fields__custom_field_id__get
   end
 
   def test_contactdb_custom_fields__custom_field_id__delete
-    custom_field_id = "test_url_param"
+    custom_field_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 202}')
 
     response = @sg.client.contactdb.custom_fields._(custom_field_id).delete(request_headers: headers)
@@ -657,7 +656,7 @@ def test_contactdb_lists__list_id__patch
 "name": "newlistname"
 }')
     params = JSON.parse('{"list_id": 1}')
-    list_id = "test_url_param"
+    list_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.lists._(list_id).patch(request_body: data, query_params: params, request_headers: headers)
@@ -667,7 +666,7 @@ def test_contactdb_lists__list_id__patch
 
   def test_contactdb_lists__list_id__get
     params = JSON.parse('{"list_id": 1}')
-    list_id = "test_url_param"
+    list_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.lists._(list_id).get(query_params: params, request_headers: headers)
@@ -677,7 +676,7 @@ def test_contactdb_lists__list_id__get
 
   def test_contactdb_lists__list_id__delete
     params = JSON.parse('{"delete_contacts": "true"}')
-    list_id = "test_url_param"
+    list_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 202}')
 
     response = @sg.client.contactdb.lists._(list_id).delete(query_params: params, request_headers: headers)
@@ -690,7 +689,7 @@ def test_contactdb_lists__list_id__recipients_post
 "recipient_id1",
 "recipient_id2"
 ]')
-    list_id = "test_url_param"
+    list_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.contactdb.lists._(list_id).recipients.post(request_body: data, request_headers: headers)
@@ -700,7 +699,7 @@ def test_contactdb_lists__list_id__recipients_post
 
   def test_contactdb_lists__list_id__recipients_get
     params = JSON.parse('{"page": 1, "page_size": 1, "list_id": 1}')
-    list_id = "test_url_param"
+    list_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.lists._(list_id).recipients.get(query_params: params, request_headers: headers)
@@ -709,8 +708,8 @@ def test_contactdb_lists__list_id__recipients_get
   end
 
   def test_contactdb_lists__list_id__recipients__recipient_id__post
-    list_id = "test_url_param"
-    recipient_id = "test_url_param"
+    list_id = 'test_url_param'
+    recipient_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.contactdb.lists._(list_id).recipients._(recipient_id).post(request_headers: headers)
@@ -720,8 +719,8 @@ def test_contactdb_lists__list_id__recipients__recipient_id__post
 
   def test_contactdb_lists__list_id__recipients__recipient_id__delete
     params = JSON.parse('{"recipient_id": 1, "list_id": 1}')
-    list_id = "test_url_param"
-    recipient_id = "test_url_param"
+    list_id = 'test_url_param'
+    recipient_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.contactdb.lists._(list_id).recipients._(recipient_id).delete(query_params: params, request_headers: headers)
@@ -804,7 +803,7 @@ def test_contactdb_recipients_count_get
   end
 
   def test_contactdb_recipients_search_get
-    params = { field_name: "test_string" }
+    params = { field_name: 'test_string' }
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.recipients.search.get(query_params: params, request_headers: headers)
@@ -813,7 +812,7 @@ def test_contactdb_recipients_search_get
   end
 
   def test_contactdb_recipients__recipient_id__get
-    recipient_id = "test_url_param"
+    recipient_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.recipients._(recipient_id).get(request_headers: headers)
@@ -822,7 +821,7 @@ def test_contactdb_recipients__recipient_id__get
   end
 
   def test_contactdb_recipients__recipient_id__delete
-    recipient_id = "test_url_param"
+    recipient_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.contactdb.recipients._(recipient_id).delete(request_headers: headers)
@@ -831,7 +830,7 @@ def test_contactdb_recipients__recipient_id__delete
   end
 
   def test_contactdb_recipients__recipient_id__lists_get
-    recipient_id = "test_url_param"
+    recipient_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.recipients._(recipient_id).lists.get(request_headers: headers)
@@ -901,7 +900,7 @@ def test_contactdb_segments__segment_id__patch
 "name": "The Millers"
 }')
     params = JSON.parse('{"segment_id": "test_string"}')
-    segment_id = "test_url_param"
+    segment_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.segments._(segment_id).patch(request_body: data, query_params: params, request_headers: headers)
@@ -911,7 +910,7 @@ def test_contactdb_segments__segment_id__patch
 
   def test_contactdb_segments__segment_id__get
     params = JSON.parse('{"segment_id": 1}')
-    segment_id = "test_url_param"
+    segment_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.segments._(segment_id).get(query_params: params, request_headers: headers)
@@ -921,7 +920,7 @@ def test_contactdb_segments__segment_id__get
 
   def test_contactdb_segments__segment_id__delete
     params = JSON.parse('{"delete_contacts": "true"}')
-    segment_id = "test_url_param"
+    segment_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.contactdb.segments._(segment_id).delete(query_params: params, request_headers: headers)
@@ -931,7 +930,7 @@ def test_contactdb_segments__segment_id__delete
 
   def test_contactdb_segments__segment_id__recipients_get
     params = JSON.parse('{"page": 1, "page_size": 1}')
-    segment_id = "test_url_param"
+    segment_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.contactdb.segments._(segment_id).recipients.get(query_params: params, request_headers: headers)
@@ -997,7 +996,7 @@ def test_ips_pools__pool_name__put
     data = JSON.parse('{
 "name": "new_pool_name"
 }')
-    pool_name = "test_url_param"
+    pool_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.ips.pools._(pool_name).put(request_body: data, request_headers: headers)
@@ -1006,7 +1005,7 @@ def test_ips_pools__pool_name__put
   end
 
   def test_ips_pools__pool_name__get
-    pool_name = "test_url_param"
+    pool_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.ips.pools._(pool_name).get(request_headers: headers)
@@ -1015,7 +1014,7 @@ def test_ips_pools__pool_name__get
   end
 
   def test_ips_pools__pool_name__delete
-    pool_name = "test_url_param"
+    pool_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.ips.pools._(pool_name).delete(request_headers: headers)
@@ -1027,7 +1026,7 @@ def test_ips_pools__pool_name__ips_post
     data = JSON.parse('{
 "ip": "0.0.0.0"
 }')
-    pool_name = "test_url_param"
+    pool_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.ips.pools._(pool_name).ips.post(request_body: data, request_headers: headers)
@@ -1036,8 +1035,8 @@ def test_ips_pools__pool_name__ips_post
   end
 
   def test_ips_pools__pool_name__ips__ip__delete
-    pool_name = "test_url_param"
-    ip = "test_url_param"
+    pool_name = 'test_url_param'
+    ip = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.ips.pools._(pool_name).ips._(ip).delete(request_headers: headers)
@@ -1065,7 +1064,7 @@ def test_ips_warmup_get
   end
 
   def test_ips_warmup__ip_address__get
-    ip_address = "test_url_param"
+    ip_address = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.ips.warmup._(ip_address).get(request_headers: headers)
@@ -1074,7 +1073,7 @@ def test_ips_warmup__ip_address__get
   end
 
   def test_ips_warmup__ip_address__delete
-    ip_address = "test_url_param"
+    ip_address = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.ips.warmup._(ip_address).delete(request_headers: headers)
@@ -1083,7 +1082,7 @@ def test_ips_warmup__ip_address__delete
   end
 
   def test_ips__ip_address__get
-    ip_address = "test_url_param"
+    ip_address = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.ips._(ip_address).get(request_headers: headers)
@@ -1100,7 +1099,7 @@ def test_mail_batch_post
   end
 
   def test_mail_batch__batch_id__get
-    batch_id = "test_url_param"
+    batch_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.mail.batch._(batch_id).get(request_headers: headers)
@@ -1249,7 +1248,7 @@ def test_mail_send_post
 }')
     headers = JSON.parse('{"X-Mock": 202}')
 
-    response = @sg.client.mail._("send").post(request_body: data, request_headers: headers)
+    response = @sg.client.mail._('send').post(request_body: data, request_headers: headers)
 
     assert_equal('202', response.status_code)
   end
@@ -1515,13 +1514,13 @@ def test_senders_post
 }')
     headers = JSON.parse('{"X-Mock": 201}')
     response = @sg.client.senders.post(request_body: data, request_headers: headers)
-    assert_equal(response.status_code, "201")
+    assert_equal(response.status_code, '201')
   end
 
   def test_senders_get
     headers = JSON.parse('{"X-Mock": 200}')
     response = @sg.client.senders.get(request_headers: headers)
-    assert_equal(response.status_code, "200")
+    assert_equal(response.status_code, '200')
   end
 
   def test_senders__sender_id__patch
@@ -1542,31 +1541,31 @@ def test_senders__sender_id__patch
 "state": "Colorado",
 "zip": "80202"
 }')
-    sender_id = "test_url_param"
+    sender_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
     response = @sg.client.senders._(sender_id).patch(request_body: data, request_headers: headers)
-    assert_equal(response.status_code, "200")
+    assert_equal(response.status_code, '200')
   end
 
   def test_senders__sender_id__get
-    sender_id = "test_url_param"
+    sender_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
     response = @sg.client.senders._(sender_id).get(request_headers: headers)
-    assert_equal(response.status_code, "200")
+    assert_equal(response.status_code, '200')
   end
 
   def test_senders__sender_id__delete
-    sender_id = "test_url_param"
+    sender_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
     response = @sg.client.senders._(sender_id).delete(request_headers: headers)
-    assert_equal(response.status_code, "204")
+    assert_equal(response.status_code, '204')
   end
 
   def test_senders__sender_id__resend_verification_post
-    sender_id = "test_url_param"
+    sender_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
     response = @sg.client.senders._(sender_id).resend_verification.post(request_headers: headers)
-    assert_equal(response.status_code, "204")
+    assert_equal(response.status_code, '204')
   end
 
   def test_stats_get
@@ -1644,7 +1643,7 @@ def test_subusers__subuser_name__patch
     data = JSON.parse('{
 "disabled": false
 }')
-    subuser_name = "test_url_param"
+    subuser_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.subusers._(subuser_name).patch(request_body: data, request_headers: headers)
@@ -1653,7 +1652,7 @@ def test_subusers__subuser_name__patch
   end
 
   def test_subusers__subuser_name__delete
-    subuser_name = "test_url_param"
+    subuser_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.subusers._(subuser_name).delete(request_headers: headers)
@@ -1665,7 +1664,7 @@ def test_subusers__subuser_name__ips_put
     data = JSON.parse('[
 "127.0.0.1"
 ]')
-    subuser_name = "test_url_param"
+    subuser_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.subusers._(subuser_name).ips.put(request_body: data, request_headers: headers)
@@ -1678,7 +1677,7 @@ def test_subusers__subuser_name__monitor_put
 "email": "example@example.com",
 "frequency": 500
 }')
-    subuser_name = "test_url_param"
+    subuser_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.subusers._(subuser_name).monitor.put(request_body: data, request_headers: headers)
@@ -1691,7 +1690,7 @@ def test_subusers__subuser_name__monitor_post
 "email": "example@example.com",
 "frequency": 50000
 }')
-    subuser_name = "test_url_param"
+    subuser_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.subusers._(subuser_name).monitor.post(request_body: data, request_headers: headers)
@@ -1700,7 +1699,7 @@ def test_subusers__subuser_name__monitor_post
   end
 
   def test_subusers__subuser_name__monitor_get
-    subuser_name = "test_url_param"
+    subuser_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.subusers._(subuser_name).monitor.get(request_headers: headers)
@@ -1709,7 +1708,7 @@ def test_subusers__subuser_name__monitor_get
   end
 
   def test_subusers__subuser_name__monitor_delete
-    subuser_name = "test_url_param"
+    subuser_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.subusers._(subuser_name).monitor.delete(request_headers: headers)
@@ -1719,7 +1718,7 @@ def test_subusers__subuser_name__monitor_delete
 
   def test_subusers__subuser_name__stats_monthly_get
     params = JSON.parse('{"date": "test_string", "sort_by_direction": "asc", "limit": 1, "sort_by_metric": "test_string", "offset": 1}')
-    subuser_name = "test_url_param"
+    subuser_name = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.subusers._(subuser_name).stats.monthly.get(query_params: params, request_headers: headers)
@@ -1752,7 +1751,7 @@ def test_suppression_blocks_delete
   end
 
   def test_suppression_blocks__email__get
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.suppression.blocks._(email).get(request_headers: headers)
@@ -1761,7 +1760,7 @@ def test_suppression_blocks__email__get
   end
 
   def test_suppression_blocks__email__delete
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.suppression.blocks._(email).delete(request_headers: headers)
@@ -1794,7 +1793,7 @@ def test_suppression_bounces_delete
   end
 
   def test_suppression_bounces__email__get
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.suppression.bounces._(email).get(request_headers: headers)
@@ -1804,7 +1803,7 @@ def test_suppression_bounces__email__get
 
   def test_suppression_bounces__email__delete
     params = JSON.parse('{"email_address": "example@example.com"}')
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.suppression.bounces._(email).delete(query_params: params, request_headers: headers)
@@ -1837,7 +1836,7 @@ def test_suppression_invalid_emails_delete
   end
 
   def test_suppression_invalid_emails__email__get
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.suppression.invalid_emails._(email).get(request_headers: headers)
@@ -1846,7 +1845,7 @@ def test_suppression_invalid_emails__email__get
   end
 
   def test_suppression_invalid_emails__email__delete
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.suppression.invalid_emails._(email).delete(request_headers: headers)
@@ -1855,7 +1854,7 @@ def test_suppression_invalid_emails__email__delete
   end
 
   def test_suppression_spam_report__email__get
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.suppression.spam_reports._(email).get(request_headers: headers)
@@ -1864,10 +1863,10 @@ def test_suppression_spam_report__email__get
   end
 
   def test_suppression_spam_report__email__delete
-    email = "test_url_param"
+    email = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
-        response = @sg.client.suppression.spam_reports._(email).delete(request_headers: headers)
+    response = @sg.client.suppression.spam_reports._(email).delete(request_headers: headers)
 
     assert_equal('204', response.status_code)
   end
@@ -1928,7 +1927,7 @@ def test_templates__template_id__patch
     data = JSON.parse('{
 "name": "new_example_name"
 }')
-    template_id = "test_url_param"
+    template_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.templates._(template_id).patch(request_body: data, request_headers: headers)
@@ -1937,7 +1936,7 @@ def test_templates__template_id__patch
   end
 
   def test_templates__template_id__get
-    template_id = "test_url_param"
+    template_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.templates._(template_id).get(request_headers: headers)
@@ -1946,7 +1945,7 @@ def test_templates__template_id__get
   end
 
   def test_templates__template_id__delete
-    template_id = "test_url_param"
+    template_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.templates._(template_id).delete(request_headers: headers)
@@ -1963,7 +1962,7 @@ def test_templates__template_id__versions_post
 "subject": "<%subject%>",
 "template_id": "ddb96bbc-9b92-425e-8979-99464621b543"
 }')
-    template_id = "test_url_param"
+    template_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.templates._(template_id).versions.post(request_body: data, request_headers: headers)
@@ -1979,8 +1978,8 @@ def test_templates__template_id__versions__version_id__patch
 "plain_content": "<%body%>",
 "subject": "<%subject%>"
 }')
-    template_id = "test_url_param"
-    version_id = "test_url_param"
+    template_id = 'test_url_param'
+    version_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.templates._(template_id).versions._(version_id).patch(request_body: data, request_headers: headers)
@@ -1989,8 +1988,8 @@ def test_templates__template_id__versions__version_id__patch
   end
 
   def test_templates__template_id__versions__version_id__get
-    template_id = "test_url_param"
-    version_id = "test_url_param"
+    template_id = 'test_url_param'
+    version_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.templates._(template_id).versions._(version_id).get(request_headers: headers)
@@ -1999,8 +1998,8 @@ def test_templates__template_id__versions__version_id__get
   end
 
   def test_templates__template_id__versions__version_id__delete
-    template_id = "test_url_param"
-    version_id = "test_url_param"
+    template_id = 'test_url_param'
+    version_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.templates._(template_id).versions._(version_id).delete(request_headers: headers)
@@ -2009,8 +2008,8 @@ def test_templates__template_id__versions__version_id__delete
   end
 
   def test_templates__template_id__versions__version_id__activate_post
-    template_id = "test_url_param"
-    version_id = "test_url_param"
+    template_id = 'test_url_param'
+    version_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.templates._(template_id).versions._(version_id).activate.post(request_headers: headers)
@@ -2205,7 +2204,7 @@ def test_user_scheduled_sends__batch_id__patch
     data = JSON.parse('{
 "status": "pause"
 }')
-    batch_id = "test_url_param"
+    batch_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.user.scheduled_sends._(batch_id).patch(request_body: data, request_headers: headers)
@@ -2214,7 +2213,7 @@ def test_user_scheduled_sends__batch_id__patch
   end
 
   def test_user_scheduled_sends__batch_id__get
-    batch_id = "test_url_param"
+    batch_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.user.scheduled_sends._(batch_id).get(request_headers: headers)
@@ -2223,7 +2222,7 @@ def test_user_scheduled_sends__batch_id__get
   end
 
   def test_user_scheduled_sends__batch_id__delete
-    batch_id = "test_url_param"
+    batch_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.user.scheduled_sends._(batch_id).delete(request_headers: headers)
@@ -2340,7 +2339,7 @@ def test_user_webhooks_parse_settings__hostname__patch
 "spam_check": false,
 "url": "http://newdomain.com/parse"
 }')
-    hostname = "test_url_param"
+    hostname = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.user.webhooks.parse.settings._(hostname).patch(request_body: data, request_headers: headers)
@@ -2349,7 +2348,7 @@ def test_user_webhooks_parse_settings__hostname__patch
   end
 
   def test_user_webhooks_parse_settings__hostname__get
-    hostname = "test_url_param"
+    hostname = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.user.webhooks.parse.settings._(hostname).get(request_headers: headers)
@@ -2358,7 +2357,7 @@ def test_user_webhooks_parse_settings__hostname__get
   end
 
   def test_user_webhooks_parse_settings__hostname__delete
-    hostname = "test_url_param"
+    hostname = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.user.webhooks.parse.settings._(hostname).delete(request_headers: headers)
@@ -2433,7 +2432,7 @@ def test_whitelabel_domains__domain_id__patch
 "custom_spf": true,
 "default": false
 }')
-    domain_id = "test_url_param"
+    domain_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.domains._(domain_id).patch(request_body: data, request_headers: headers)
@@ -2442,7 +2441,7 @@ def test_whitelabel_domains__domain_id__patch
   end
 
   def test_whitelabel_domains__domain_id__get
-    domain_id = "test_url_param"
+    domain_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.domains._(domain_id).get(request_headers: headers)
@@ -2451,7 +2450,7 @@ def test_whitelabel_domains__domain_id__get
   end
 
   def test_whitelabel_domains__domain_id__delete
-    domain_id = "test_url_param"
+    domain_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.whitelabel.domains._(domain_id).delete(request_headers: headers)
@@ -2463,7 +2462,7 @@ def test_whitelabel_domains__domain_id__subuser_post
     data = JSON.parse('{
 "username": "jane@example.com"
 }')
-    domain_id = "test_url_param"
+    domain_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 201}')
 
     response = @sg.client.whitelabel.domains._(domain_id).subuser.post(request_body: data, request_headers: headers)
@@ -2475,7 +2474,7 @@ def test_whitelabel_domains__id__ips_post
     data = JSON.parse('{
 "ip": "192.168.0.1"
 }')
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.domains._(id).ips.post(request_body: data, request_headers: headers)
@@ -2484,8 +2483,8 @@ def test_whitelabel_domains__id__ips_post
   end
 
   def test_whitelabel_domains__id__ips__ip__delete
-    id = "test_url_param"
-    ip = "test_url_param"
+    id = 'test_url_param'
+    ip = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.domains._(id).ips._(ip).delete(request_headers: headers)
@@ -2494,7 +2493,7 @@ def test_whitelabel_domains__id__ips__ip__delete
   end
 
   def test_whitelabel_domains__id__validate_post
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.domains._(id).validate.post(request_headers: headers)
@@ -2525,7 +2524,7 @@ def test_whitelabel_ips_get
   end
 
   def test_whitelabel_ips__id__get
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.ips._(id).get(request_headers: headers)
@@ -2534,7 +2533,7 @@ def test_whitelabel_ips__id__get
   end
 
   def test_whitelabel_ips__id__delete
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.whitelabel.ips._(id).delete(request_headers: headers)
@@ -2543,7 +2542,7 @@ def test_whitelabel_ips__id__delete
   end
 
   def test_whitelabel_ips__id__validate_post
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.ips._(id).validate.post(request_headers: headers)
@@ -2605,7 +2604,7 @@ def test_whitelabel_links__id__patch
     data = JSON.parse('{
 "default": true
 }')
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.links._(id).patch(request_body: data, request_headers: headers)
@@ -2614,7 +2613,7 @@ def test_whitelabel_links__id__patch
   end
 
   def test_whitelabel_links__id__get
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.links._(id).get(request_headers: headers)
@@ -2623,7 +2622,7 @@ def test_whitelabel_links__id__get
   end
 
   def test_whitelabel_links__id__delete
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 204}')
 
     response = @sg.client.whitelabel.links._(id).delete(request_headers: headers)
@@ -2632,7 +2631,7 @@ def test_whitelabel_links__id__delete
   end
 
   def test_whitelabel_links__id__validate_post
-    id = "test_url_param"
+    id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.links._(id).validate.post(request_headers: headers)
@@ -2644,7 +2643,7 @@ def test_whitelabel_links__link_id__subuser_post
     data = JSON.parse('{
 "username": "jane@example.com"
 }')
-    link_id = "test_url_param"
+    link_id = 'test_url_param'
     headers = JSON.parse('{"X-Mock": 200}')
 
     response = @sg.client.whitelabel.links._(link_id).subuser.post(request_body: data, request_headers: headers)
@@ -2655,7 +2654,7 @@ def test_whitelabel_links__link_id__subuser_post
   def test_license_file_year
     # Read the third line from the license file
     year = IO.readlines('./LICENSE.md')[2].gsub(/[^\d]/, '')
-    self.assert_equal("#{Time.now.year}", year)
+    assert_equal(Time.now.year.to_s, year)
   end
 
   def test_env_sample_exists