add support precision of DateTime selectors when encoding/decoding cu…

…rsors add spec coverage for timestamp order_by selector in pagination fetch

Bump version to 0.3.1

.github/workflows/test.yml

@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-18.04
     strategy:
       matrix:
-        ruby-version: ['2.6', '2.7', '3.0', '3.1']
+        ruby-version: ['2.7', '3.0', '3.1']
         mysql-version: ['5.7', '8.0']
 
     steps:
@@ -49,7 +49,7 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        ruby-version: ['2.6', '2.7', '3.0', '3.1']
+        ruby-version: ['2.7', '3.0', '3.1']
         postgres-version: [14, 13, 12]
 
     steps:

.ruby-version

@@ -1 +1 @@
-ruby-2.7.5
+2.7.4

CHANGELOG.md

@@ -14,6 +14,11 @@ These are the latest changes on the project's `master` branch that have not yet
   Follow the same format as previous releases by categorizing your feature into "Added", "Changed", "Deprecated", "Removed", "Fixed", or "Security".
 --->
 
+## [0.3.1] - 2023-01-13
+
+### Fixed
+- Ensure DateTime order_by fields will have expected paginated results by honoring of timestamps down to nanosecond on comparison.
+
 ## [0.3.0] - 2022-07-08
 
 ### Added

Gemfile

@@ -14,3 +14,4 @@ gem 'rubocop', '~> 1.31'
 gem 'mysql2', '~> 0.5'
 
 gem 'pg', '~> 1.4'
+

Gemfile.lock

@@ -1,38 +1,37 @@
 PATH
   remote: .
   specs:
-    rails_cursor_pagination (0.3.0)
+    rails_cursor_pagination (0.3.1)
       activerecord (>= 5.0)
 
 GEM
   remote: https://rubygems.org/
   specs:
-    activemodel (6.1.6)
-      activesupport (= 6.1.6)
-    activerecord (6.1.6)
-      activemodel (= 6.1.6)
-      activesupport (= 6.1.6)
-    activesupport (6.1.6)
+    activemodel (7.0.4.2)
+      activesupport (= 7.0.4.2)
+    activerecord (7.0.4.2)
+      activemodel (= 7.0.4.2)
+      activesupport (= 7.0.4.2)
+    activesupport (7.0.4.2)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
       tzinfo (~> 2.0)
-      zeitwerk (~> 2.3)
     ast (2.4.2)
-    concurrent-ruby (1.1.10)
+    concurrent-ruby (1.2.0)
     diff-lcs (1.5.0)
-    i18n (1.10.0)
+    i18n (1.12.0)
       concurrent-ruby (~> 1.0)
-    json (2.6.2)
-    minitest (5.15.0)
-    mysql2 (0.5.4)
+    json (2.6.3)
+    minitest (5.17.0)
+    mysql2 (0.5.5)
     parallel (1.22.1)
-    parser (3.1.2.0)
+    parser (3.2.0.0)
       ast (~> 2.4.1)
     pg (1.4.1)
     rainbow (3.1.1)
     rake (13.0.6)
-    regexp_parser (2.5.0)
+    regexp_parser (2.6.2)
     rexml (3.2.5)
     rspec (3.11.0)
       rspec-core (~> 3.11.0)
@@ -47,23 +46,22 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.11.0)
     rspec-support (3.11.0)
-    rubocop (1.31.2)
+    rubocop (1.44.1)
       json (~> 2.3)
       parallel (~> 1.10)
-      parser (>= 3.1.0.0)
+      parser (>= 3.2.0.0)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 1.8, < 3.0)
       rexml (>= 3.2.5, < 4.0)
-      rubocop-ast (>= 1.18.0, < 2.0)
+      rubocop-ast (>= 1.24.1, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 1.4.0, < 3.0)
-    rubocop-ast (1.18.0)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.24.1)
       parser (>= 3.1.1.0)
     ruby-progressbar (1.11.0)
-    tzinfo (2.0.4)
+    tzinfo (2.0.5)
       concurrent-ruby (~> 1.0)
-    unicode-display_width (2.2.0)
-    zeitwerk (2.5.4)
+    unicode-display_width (2.4.2)
 
 PLATFORMS
   ruby
@@ -77,4 +75,4 @@ DEPENDENCIES
   rubocop (~> 1.31)
 
 BUNDLED WITH
-   2.1.4
+   2.2.3

lib/rails_cursor_pagination/cursor.rb

@@ -42,18 +42,35 @@ def decode(encoded_string:, order_field: :id)
           end
           new(id: decoded, order_field: :id)
         else
-          unless decoded.is_a?(Array) && decoded.size == 2
-            raise InvalidCursorError,
-                  "The given cursor `#{encoded_string}` was decoded as " \
-                  "`#{decoded}` but could not be parsed"
-          end
-          new(id: decoded[1], order_field: order_field,
-              order_field_value: decoded[0])
+          decode_custom_order_field(encoded_string: encoded_string,
+              decoded: decoded, order_field: order_field)
         end
       rescue ArgumentError, JSON::ParserError
         raise InvalidCursorError,
               "The given cursor `#{encoded_string}` could not be decoded"
       end
+
+      def decode_custom_order_field(encoded_string:, decoded:, order_field:)
+        unless decoded.is_a?(Array) && decoded.size == 2
+          raise InvalidCursorError,
+                "The given cursor `#{encoded_string}` was decoded as " \
+                "`#{decoded}` but could not be parsed"
+        end
+        if decoded[0].is_a?(Hash) && ['seconds', 'nanoseconds'].all? { |key| decoded[0].key? key }
+          new(
+            id: decoded[1],
+            order_field: order_field,
+            order_field_value: Time.at(
+              decoded[0]['seconds'],
+              decoded[0]['nanoseconds'],
+              :nsec
+            )
+          )
+        else
+          new(id: decoded[1], order_field: order_field,
+              order_field_value: decoded[0])
+        end
+      end
     end
 
     # Initializes the record
@@ -89,7 +106,14 @@ def initialize(id:, order_field: :id, order_field_value: nil)
     def encode
       unencoded_cursor =
         if custom_order_field?
-          [@order_field_value, @id]
+          if @order_field_value.respond_to?(:strftime)
+            [{
+              seconds: order_field_value.to_i,
+              nanoseconds: order_field_value.nsec
+            }, @id]
+          else
+            [@order_field_value, @id]
+          end
         else
           @id
         end

lib/rails_cursor_pagination/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module RailsCursorPagination
-  VERSION = '0.3.0'
-end
+  VERSION = '0.3.1'
+end

spec/rails_cursor_pagination/cursor_spec.rb

@@ -51,6 +51,23 @@
         expect(decoded.order_field_value).to eq record.author
       end
     end
+
+    context 'when ordering by created_at' do
+      subject(:encoded) do
+        described_class.from_record(record: record, order_field: :created_at).encode
+      end
+
+      it 'produces a valid string' do
+        expect(encoded).to be_a(String)
+      end
+
+      it 'can be decoded back to the originally encoded value' do
+        decoded = described_class.decode(encoded_string: encoded,
+                                         order_field: :created_at)
+        expect(decoded.id).to eq record.id
+        expect(decoded.order_field_value).to eq record.created_at
+      end
+    end
   end
 
   describe '.from_record' do
@@ -156,6 +173,40 @@
       end
     end
 
+    context 'when decoding an encoded message with order_field :created_at' do
+      let(:record) { Post.create! id: 1, author: 'John', content: 'Post 1' }
+      let(:encoded) do
+        described_class.from_record(record: record, order_field: :created_at).encode
+      end
+
+      context 'and the order_field to decode is set to :id' do
+        subject(:decoded) do
+          described_class.decode(encoded_string: encoded)
+        end
+
+        it 'raises an InvalidCursorError' do
+          cursor = [{"seconds"=> record.created_at.to_i, "nanoseconds"=> record.created_at.nsec}, record.id]
+          msg = %Q|The given cursor `#{encoded}` was decoded as `#{cursor}` but could not be parsed|
+          expect { decoded }.to raise_error(
+            ::RailsCursorPagination::InvalidCursorError,
+            msg
+          )
+        end
+      end
+
+      context 'and the order_field to decode is set to :created_at' do
+        subject(:decoded) do
+          described_class.decode(encoded_string: encoded, order_field: :created_at)
+        end
+
+        it 'decodes the string succesfully' do
+          expect(decoded.id).to eq record.id
+          expect(decoded.order_field_value).to eq record.created_at
+          expect(decoded.order_field_value.nsec).to eq record.created_at.nsec
+        end
+      end
+    end
+
     context 'when decoding a message that did not come from a known encoder' do
       let(:encoded) { 'SomeGarbageString' }