Drop dependency on Google API Client

This commit makes several changes, first, it replaces Google API Client
with custom code using Faraday to call the JSON REST API.
The new code uses the new Translate endpoint, switched to HTTP POST,
and adds support for service accounts in addition to API keys.

[closes #1046, closes #1047, closes #1049]

google-cloud-translate/Rakefile

@@ -25,20 +25,63 @@ end
 
 # Acceptance tests
 desc "Runs the translate acceptance tests."
-task :acceptance, :key do |t, args|
+task :acceptance, :project, :keyfile, :key do |t, args|
+  project = args[:project]
+  project ||= ENV["GCLOUD_TEST_PROJECT"] || ENV["TRANSLATE_TEST_PROJECT"]
+  keyfile = args[:keyfile]
+  keyfile ||= ENV["GCLOUD_TEST_KEYFILE"] || ENV["TRANSLATE_TEST_KEYFILE"]
+  if keyfile
+    keyfile = File.read keyfile
+  else
+    keyfile ||= ENV["GCLOUD_TEST_KEYFILE_JSON"] || ENV["TRANSLATE_TEST_KEYFILE_JSON"]
+  end
+  if project.nil? || keyfile.nil?
+    fail "You must provide a project and keyfile. e.g. rake acceptance[test123, /path/to/keyfile.json] or TRANSLATE_TEST_PROJECT=test123 TRANSLATE_TEST_KEYFILE=/path/to/keyfile.json rake acceptance"
+  end
   key = args[:key]
   key ||= ENV["GCLOUD_TEST_KEY"] || ENV["TRANSLATE_TEST_KEY"]
-  if key.nil?
-    fail "You must provide a key. e.g. rake acceptance[api_key] or TRANSLATE_TEST_KEY=api_key rake acceptance"
+
+  # run tests with api key credentials when available
+  if key
+    puts "running acceptance tests with API key"
+    # Rake::Task["acceptance:key"].invoke key
+    puts `bundle exec rake acceptance:key[#{key}]`
   end
+
+  # always run tests with service account credentials
+  puts "running acceptance tests with service account"
+
   # always overwrite when running tests
-  ENV["TRANSLATE_KEY"] = key
+  ENV["TRANSLATE_PROJECT"] = project
+  ENV["TRANSLATE_KEYFILE"] = nil
+  ENV["TRANSLATE_KEYFILE_JSON"] = keyfile
+  ENV["TRANSLATE_KEY"] = nil
 
   $LOAD_PATH.unshift "lib", "acceptance"
   Dir.glob("acceptance/**/*_test.rb").each { |file| require_relative file }
 end
 
 namespace :acceptance do
+  task :key, :key do |t, args|
+    key = args[:key]
+    key ||= ENV["GCLOUD_TEST_KEY"] || ENV["TRANSLATE_TEST_KEY"]
+    if key.nil?
+      fail "unable to run acceptance tests with api key credentials"
+    end
+    # always overwrite when running tests
+    ENV["TRANSLATE_PROJECT"] = nil
+    ENV["TRANSLATE_KEYFILE"] = nil
+    ENV["GOOGLE_CLOUD_KEYFILE"] = nil
+    ENV["GCLOUD_KEYFILE"] = nil
+    ENV["TRANSLATE_KEYFILE_JSON"] = nil
+    ENV["GOOGLE_CLOUD_KEYFILE_JSON"] = nil
+    ENV["GCLOUD_KEYFILE_JSON"] = nil
+    ENV["TRANSLATE_KEY"] = key
+
+    $LOAD_PATH.unshift "lib", "acceptance"
+    Dir.glob("acceptance/**/*_test.rb").each { |file| require_relative file }
+  end
+
   desc "Runs acceptance tests with coverage."
   task :coverage, :project, :keyfile do |t, args|
     require "simplecov"

google-cloud-translate/google-cloud-translate.gemspec

@@ -19,7 +19,6 @@ Gem::Specification.new do |gem|
   gem.required_ruby_version = ">= 2.0.0"
 
   gem.add_dependency "google-cloud-core", "~> 0.21.0"
-  gem.add_dependency "google-api-client", "~> 0.9.11"
 
   gem.add_development_dependency "minitest", "~> 5.9"
   gem.add_development_dependency "minitest-autotest", "~> 1.0"

google-cloud-translate/lib/google-cloud-translate.rb

@@ -36,6 +36,14 @@ module Cloud
     # keys](https://cloud.google.com/translate/v2/using_rest#creating-server-api-keys).
     #
     # @param [String] key a public API access key (not an OAuth 2.0 token)
+    # @param [String, Array<String>] scope The OAuth 2.0 scopes controlling the
+    #   set of resources and operations that the connection can access. See
+    #   [Using OAuth 2.0 to Access Google
+    #   APIs](https://developers.google.com/identity/protocols/OAuth2).
+    #
+    #   The default scope is:
+    #
+    #   * `https://www.googleapis.com/auth/cloud-platform`
     # @param [Integer] retries Number of times to retry requests on server
     #   error. The default value is `3`. Optional.
     # @param [Integer] timeout Default timeout to use in requests. Optional.
@@ -62,8 +70,10 @@ module Cloud
     #   translation = translate.translate "Hello world!", to: "la"
     #   translation.text #=> "Salve mundi!"
     #
-    def translate key = nil, retries: nil, timeout: nil
-      Google::Cloud.translate key, retries: (retries || @retries),
+    def translate key = nil, scope: nil, retries: nil, timeout: nil
+      Google::Cloud.translate key, project: @project, keyfile: @keyfile,
+                                   scope: scope,
+                                   retries: (retries || @retries),
                                    timeout: (timeout || @timeout)
     end
 
@@ -80,6 +90,18 @@ def translate key = nil, retries: nil, timeout: nil
     # keys](https://cloud.google.com/translate/v2/using_rest#creating-server-api-keys).
     #
     # @param [String] key a public API access key (not an OAuth 2.0 token)
+    # @param [String] project Project identifier for the Translate service you
+    #   are connecting to.
+    # @param [String, Hash] keyfile Keyfile downloaded from Google Cloud. If
+    #   file path the file must be readable.
+    # @param [String, Array<String>] scope The OAuth 2.0 scopes controlling the
+    #   set of resources and operations that the connection can access. See
+    #   [Using OAuth 2.0 to Access Google
+    #   APIs](https://developers.google.com/identity/protocols/OAuth2).
+    #
+    #   The default scope is:
+    #
+    #   * `https://www.googleapis.com/auth/cloud-platform`
     # @param [Integer] retries Number of times to retry requests on server
     #   error. The default value is `3`. Optional.
     # @param [Integer] timeout Default timeout to use in requests. Optional.
@@ -104,9 +126,12 @@ def translate key = nil, retries: nil, timeout: nil
     #   translation = translate.translate "Hello world!", to: "la"
     #   translation.text #=> "Salve mundi!"
     #
-    def self.translate key = nil, retries: nil, timeout: nil
+    def self.translate key = nil, project: nil, keyfile: nil, scope: nil,
+                       retries: nil, timeout: nil
       require "google/cloud/translate"
-      Google::Cloud::Translate.new key: key, retries: retries, timeout: timeout
+      Google::Cloud::Translate.new key: key, project: project, keyfile: keyfile,
+                                   scope: scope, retries: retries,
+                                   timeout: timeout
     end
   end
 end

google-cloud-translate/lib/google/cloud/translate.rb

@@ -219,6 +219,18 @@ module Translate
       # the specific instructions for [Server
       # keys](https://cloud.google.com/translate/v2/using_rest#creating-server-api-keys).
       #
+      # @param [String] project Project identifier for the Translate service you
+      #   are connecting to.
+      # @param [String, Hash] keyfile Keyfile downloaded from Google Cloud. If
+      #   file path the file must be readable.
+      # @param [String, Array<String>] scope The OAuth 2.0 scopes controlling
+      #   the set of resources and operations that the connection can access.
+      #   See [Using OAuth 2.0 to Access Google
+      #   APIs](https://developers.google.com/identity/protocols/OAuth2).
+      #
+      #   The default scope is:
+      #
+      #   * `https://www.googleapis.com/auth/cloud-platform`
       # @param [String] key a public API access key (not an OAuth 2.0 token)
       # @param [Integer] retries Number of times to retry requests on server
       #   error. The default value is `3`. Optional.
@@ -229,7 +241,20 @@ module Translate
       # @example
       #   require "google/cloud/translate"
       #
-      #   translate = Google::Cloud::Translate.new key: "api-key-abc123XYZ789"
+      #   translate = Google::Cloud::Translate.new(
+      #     project: "my-todo-project",
+      #     keyfile: "/path/to/keyfile.json"
+      #   )
+      #
+      #   translation = translate.translate "Hello world!", to: "la"
+      #   translation.text #=> "Salve mundi!"
+      #
+      # @example Using API Key.
+      #   require "google/cloud/translate"
+      #
+      #   translate = Google::Cloud::Translate.new(
+      #     key: "api-key-abc123XYZ789"
+      #   )
       #
       #   translation = translate.translate "Hello world!", to: "la"
       #   translation.text #=> "Salve mundi!"
@@ -244,17 +269,30 @@ module Translate
       #   translation = translate.translate "Hello world!", to: "la"
       #   translation.text #=> "Salve mundi!"
       #
-      def self.new key: nil, retries: nil, timeout: nil
+      def self.new project: nil, keyfile: nil, scope: nil, key: nil,
+                   retries: nil, timeout: nil
+        project ||= Google::Cloud::Translate::Api.default_project
+        project = project.to_s # Always cast to a string
+
         key ||= ENV["TRANSLATE_KEY"]
         key ||= ENV["GOOGLE_CLOUD_KEY"]
-        if key.nil?
-          key_missing_msg = "An API key is required to use the Translate API."
-          fail ArgumentError, key_missing_msg
+        if key
+          return Google::Cloud::Translate::Api.new(
+            Google::Cloud::Translate::Service.new(
+              project, nil, retries: retries, timeout: timeout, key: key))
+        end
+
+        if keyfile.nil?
+          credentials = Google::Cloud::Translate::Credentials.default(
+            scope: scope)
+        else
+          credentials = Google::Cloud::Translate::Credentials.new(
+            keyfile, scope: scope)
         end
 
         Google::Cloud::Translate::Api.new(
           Google::Cloud::Translate::Service.new(
-            key, retries: retries, timeout: timeout))
+            project, credentials, retries: retries, timeout: timeout))
       end
     end
   end

google-cloud-translate/lib/google/cloud/translate/api.rb

@@ -13,6 +13,7 @@
 # limitations under the License.
 
 
+require "google/cloud/core/environment"
 require "google/cloud/translate/service"
 require "google/cloud/translate/translation"
 require "google/cloud/translate/detection"
@@ -62,6 +63,32 @@ def initialize service
           @service = service
         end
 
+        ##
+        # The Translate project connected to.
+        #
+        # @example
+        #   require "google/cloud/translate"
+        #
+        #   translate = Google::Cloud::Translate.new(
+        #     project: "my-todo-project",
+        #     keyfile: "/path/to/keyfile.json"
+        #   )
+        #
+        #   translate.project #=> "my-todo-project"
+        #
+        def project
+          service.project
+        end
+
+        ##
+        # @private Default project.
+        def self.default_project
+          ENV["TRANSLATE_PROJECT"] ||
+            ENV["GOOGLE_CLOUD_PROJECT"] ||
+            ENV["GCLOUD_PROJECT"] ||
+            Google::Cloud::Core::Environment.project_id
+        end
+
         ##
         # Returns text translations from one language to another.
         #
@@ -227,7 +254,7 @@ def detect *text
         def languages language = nil
           language = language.to_s if language
           gapi = service.languages language
-          Array(gapi.languages).map { |g| Language.from_gapi g }
+          Array(gapi["languages"]).map { |g| Language.from_gapi g }
         end
       end
     end

google-cloud-translate/lib/google/cloud/translate/credentials.rb

@@ -0,0 +1,42 @@
+# Copyright 2016 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+require "google/cloud/credentials"
+
+module Google
+  module Cloud
+    module Translate
+      ##
+      # @private Represents the OAuth 2.0 signing logic for Translate.
+      class Credentials < Google::Cloud::Credentials
+        SCOPE = ["https://www.googleapis.com/auth/cloud-platform"]
+        PATH_ENV_VARS = %w(TRANSLATE_KEYFILE GOOGLE_CLOUD_KEYFILE
+                           GCLOUD_KEYFILE)
+        JSON_ENV_VARS = %w(TRANSLATE_KEYFILE_JSON GOOGLE_CLOUD_KEYFILE_JSON
+                           GCLOUD_KEYFILE_JSON)
+
+        ##
+        # @private Sign Oauth2 API calls.
+        def sign_http_request request #:nodoc:
+          if @client
+            @client.fetch_access_token! if @client.expires_within? 30
+            @client.generate_authenticated_request request: request
+          end
+          request
+        end
+      end
+    end
+  end
+end

google-cloud-translate/lib/google/cloud/translate/detection.rb

@@ -88,8 +88,8 @@ def language
         # @private New Detection from a ListDetectionsResponse object as
         # defined by the Google API Client object.
         def self.from_gapi gapi, text
-          res = text.zip(Array(gapi.detections)).map do |txt, detections_gapi|
-            results = detections_gapi.map { |g| Result.from_gapi g }
+          res = text.zip(Array(gapi["detections"])).map do |txt, detections|
+            results = detections.map { |g| Result.from_gapi g }
             new txt, results
           end
           return res.first if res.size == 1
@@ -130,7 +130,7 @@ def initialize confidence, language
           # @private New Detection::Result from a DetectionsResource object as
           # defined by the Google API Client object.
           def self.from_gapi gapi
-            new gapi.confidence, gapi.language
+            new gapi["confidence"], gapi["language"]
           end
         end
       end

google-cloud-translate/lib/google/cloud/translate/language.rb

@@ -62,7 +62,7 @@ def initialize code, name
         # @private New Language from a LanguagesResource object as defined by
         # the Google API Client object.
         def self.from_gapi gapi
-          new gapi.language, gapi.name
+          new gapi["language"], gapi["name"]
         end
       end
     end