Merge branch 'cloud_translation'

Author: vincentvanbush

README.md

@@ -107,6 +107,79 @@ Keys marked as deleted (i.e. still existing but deleted from the Lit UI) are *no
 
 Deleted keys whose translations are encountered during import are restored automatically.
 
+### Cloud translation services
+
+Lit can use external translation services such as [Google Cloud Translation API](https://cloud.google.com/translate/) and [Yandex.Translate API](https://translate.yandex.com/developers) to tentatively translate localizations to a given language.
+Currently, Google and Yandex translation providers are supported, but extending it to any other translation provider of your choice is as easy as subclassing `Lit::CloudTranslation::Providers::Base`; see classes in `lib/lit/cloud_translation/providers` for reference.
+
+#### Usage
+
+Configure your translation provider using one of routines described below. When a translation provider is configured, each localization in Lit web UI will have a "Translate using _Provider Name_" button next to it, which by default translates to the localization's language from the localization currently saved for the app's `I18n.default_locale`.
+Next to the button, there is a dropdown that allows translating from the key's localization in a language different than the default one.
+
+#### Google Cloud Translation API
+
+Insert this into your Lit initializer:
+```
+require 'lit/cloud_translation/providers/google'
+
+Lit::CloudTranslation.provider = Lit::CloudTranslation::Providers::Google
+```
+
+...and make sure you have this in your Gemfile:
+```
+gem 'google-cloud-translate'
+```
+
+To use translation via Google, you need to obtain a [service account key](https://cloud.google.com/iam/docs/creating-managing-service-account-keys) containing all the credentials required by the API.
+
+These credentials can be given in three ways:
+* via a `.json` keyfile, the path to which should be stored in the `GOOGLE_TRANSLATE_API_KEYFILE` environment variable,
+* programmatically, in the initializer - be sure to use secrets in all the sensitive fields so you don't expose private credentials in the code:
+  ```
+  Lit::CloudTranslation.configure do |config|
+    config.keyfile_hash = {
+      'type' => 'service_account',
+      'project_id' => 'foo',
+      'private_key_id' => 'keyid',
+      ... # see Google docs link above for reference
+    }
+  end
+  ```
+* directly via `GOOGLE_TRANSLATE_API_<element>` environment variables, where e.g. the `GOOGLE_TRANSLATE_API_PROJECT_ID` variable corresponds to the `project_id` element of a JSON keyfile. Typically, only the following variables are mandatory:
+  * `GOOGLE_TRANSLATE_API_PROJECT_ID`
+  * `GOOGLE_TRANSLATE_API_PRIVATE_KEY` (make sure that it contains correct line breaks and markers of the private key's begin and end)
+  * `GOOGLE_TRANSLATE_API_CLIENT_EMAIL`
+
+#### Yandex.Translate API
+
+Insert this into your Lit initializer:
+```
+require 'lit/cloud_translation/providers/yandex'
+
+Lit::CloudTranslation.provider = Lit::CloudTranslation::Providers::Yandex
+```
+
+To use Yandex translation, an [API key must be obtained](https://translate.yandex.com/developers/keys). Then, you can pass it to your application via the `YANDEX_TRANSLATE_API_KEY` environment variable.
+
+The API key can also be set programmatically in your Lit initializer (again, be sure to use secrets if you choose to do so):
+```
+Lit::CloudTranslation.configure do |config|
+  config.api_key = 'the_api_key'
+end
+```
+
+### 0.3 -> 1.0 upgrade guide
+
+Also applies to upgrading from `0.4.pre.alpha` versions.
+
+1. Specify `gem 'lit', '~> 1.0'` in your Gemfile and run `bundle update lit`.
+2. Run Lit migrations - `rails db:migrate`.
+   * __Caution:__ One of the new migrations adds a unique index in `lit_localizations` on `(localization_key_id, locale_id)`, which may cause constraint violations in some cases. If you encounter such errors during running this migration - in this case you'll need to enter Rails console and remove duplicates manually. The following query might be helpful to determine duplicate locale/localization key ID pairs:
+   ```
+   Lit::Localization.group(:locale_id, :localization_key_id).having('count(*) > 1').count
+   ```
+
 ### 0.2 -> 0.3 upgrade guide
 
 1. Specify exact lit version in your Gemfile: `gem 'lit', '~> 0.3.0'`

app/controllers/lit/cloud_translations_controller.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module Lit
+  class CloudTranslationsController < ::Lit::ApplicationController
+    def show
+      params.delete(:from) if params[:from] == 'auto'
+      @target_localization = Localization.find(params[:localization_id])
+      @localization_key = @target_localization.localization_key
+      if params[:from]
+        @localization = @localization_key.localizations.joins(:locale)
+                                         .find_by!(lit_locales: { locale: params[:from] })
+      end
+      opts =
+        {
+          # if :from was auto, translate from the target localization's
+          # current text itself
+          text: (@localization || @target_localization).value,
+          from: params[:from],
+          to: @target_localization.locale.locale
+        }.compact
+      @translated_text = Lit::CloudTranslation.translate(opts)
+    rescue Lit::CloudTranslation::TranslationError => e
+      @error_message = "Translation failed. #{e.message}"
+    end
+  end
+end

app/controllers/lit/localizations_controller.rb

@@ -48,7 +48,8 @@ def find_localization_key
     end
 
     def find_localization
-      @localization = @localization_key.localizations.find(params[:id])
+      @localization =
+        @localization_key.localizations.includes(:locale).find(params[:id])
     end
 
     def after_update_operations

app/helpers/lit/localizations_helper.rb

@@ -12,5 +12,9 @@ def ejs(val)
     def allow_wysiwyg_editor?(key)
       Lit.all_translations_are_html_safe || key.to_s =~ /(\b|_|\.)html$/
     end
+
+    def available_locales_with_default_first
+      I18n.available_locales.sort_by { |l| l == I18n.default_locale ? 0 : 1 }
+    end
   end
 end

app/views/lit/cloud_translations/show.js.erb

@@ -0,0 +1,14 @@
+<% if @translated_text.is_a?(String) %>
+  $('.localization_row[data-id="<%= @target_localization.id %>"] textarea').val("<%= j @translated_text %>");
+<% elsif @translated_text.is_a?(Array) %>
+  $inputs = $('.localization_row[data-id="<%= @target_localization.id %>"] input[type=text]');
+  var translated_elements = JSON.parse("<%= j @translated_text.to_json.html_safe %>");
+  for (i in $inputs.toArray()) {
+    $input = $($inputs[i]);
+    $input.val(translated_elements[i]);
+  }
+<% elsif @error_message.present? %>
+  alert("<%= j @error_message %>")
+<% else %>
+  alert("An unknown error has occurred while translating.")
+<% end %>

app/views/lit/localizations/_form.html.erb

@@ -19,5 +19,32 @@
 
   <button class="btn btn-primary btn-sm" type="submit"><%= I18n.t('lit.common.update', default: "Update") %></button>
   <button class="btn btn-default btn-sm cancel" type="reset"><%= I18n.t('lit.common.cancel', default: 'Cancel') %></button>
+
+  <% if Lit::CloudTranslation.provider %>
+    <div class="btn-group pull-right">
+      <%= link_to "Translate using #{Lit::CloudTranslation.provider.name.demodulize}", cloud_translation_path(from: I18n.default_locale, localization_id: @localization.id), remote: true, class: 'btn btn-sm btn-default' %>
+      <button class="btn btn-sm dropdown-toggle" data-toggle="dropdown">
+        <span class="caret"></span>
+        <span class="sr-only">Source languages</span>
+      </button>
+      <ul class="dropdown-menu">
+        <li>
+          <a>Translate from:</a>
+        </li>
+        <li role="separator" class="divider"></li>
+        <% (available_locales_with_default_first + [:auto]).each_with_index do |source_locale, i| %>
+          <li>
+            <%= link_to cloud_translation_path(from: source_locale, localization_id: @localization.id), remote: true do %>
+              <% if i == 0 %>
+                <strong><%= source_locale.to_s %></strong>
+              <% else %>
+                <%= source_locale.to_s %>
+              <% end %>
+            <% end %>
+          </li>
+        <% end %>
+      </ul>
+    </div>
+  <% end %>
 <% end %>
 

config/routes.rb

@@ -50,5 +50,7 @@
     end
   end
 
+  resource :cloud_translation, only: :show
+
   root to: 'dashboard#index'
 end

gemfiles/rails_4.2.gemfile.lock

@@ -53,6 +53,7 @@ GEM
     arel (6.0.4)
     bcrypt (3.1.12)
     builder (3.2.3)
+    byebug (10.0.2)
     capybara (3.12.0)
       addressable
       mini_mime (>= 0.1.3)
@@ -82,35 +83,66 @@ GEM
       warden (~> 1.2.3)
     erubis (2.7.0)
     execjs (2.7.0)
+    faraday (0.15.4)
+      multipart-post (>= 1.2, < 3)
     ffi (1.9.25)
     globalid (0.4.1)
       activesupport (>= 4.2.0)
+    google-cloud-core (1.2.7)
+      google-cloud-env (~> 1.0)
+    google-cloud-env (1.0.5)
+      faraday (~> 0.11)
+    google-cloud-translate (1.2.4)
+      faraday (~> 0.13)
+      google-cloud-core (~> 1.2)
+      googleauth (~> 0.6.2)
+    googleauth (0.6.7)
+      faraday (~> 0.12)
+      jwt (>= 1.4, < 3.0)
+      memoist (~> 0.16)
+      multi_json (~> 1.11)
+      os (>= 0.9, < 2.0)
+      signet (~> 0.7)
     hashdiff (0.3.7)
     i18n (0.9.5)
       concurrent-ruby (~> 1.0)
     jquery-rails (4.3.3)
       rails-dom-testing (>= 1, < 3)
       railties (>= 4.2.0)
       thor (>= 0.14, < 2.0)
+    jwt (2.1.0)
     loofah (2.2.3)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.7.1)
       mini_mime (>= 0.1.1)
+    memoist (0.16.0)
     metaclass (0.0.4)
     method_source (0.9.2)
     mini_mime (1.0.1)
     mini_portile2 (2.3.0)
+    minispec-metadata (2.0.0)
+      minitest
     minitest (5.11.3)
+    minitest-vcr (1.4.0)
+      minispec-metadata (~> 2.0)
+      minitest (>= 4.7.5)
+      vcr (>= 2.9)
     mocha (1.7.0)
       metaclass (~> 0.0.1)
+    multi_json (1.13.1)
+    multipart-post (2.0.0)
     nokogiri (1.8.5)
       mini_portile2 (~> 2.3.0)
     orm_adapter (0.5.0)
+    os (1.0.0)
     pg (0.18.4)
     pry (0.12.2)
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
+    pry-byebug (3.6.0)
+      byebug (~> 10.0)
+      pry (~> 0.10)
     pry-rails (0.3.7)
       pry (>= 0.10.4)
     public_suffix (3.0.3)
@@ -162,6 +194,11 @@ GEM
       sprockets (>= 2.8, < 4.0)
       sprockets-rails (>= 2.0, < 4.0)
       tilt (>= 1.1, < 3)
+    signet (0.11.0)
+      addressable (~> 2.3)
+      faraday (~> 0.9)
+      jwt (>= 1.5, < 3.0)
+      multi_json (~> 1.10)
     sprockets (3.7.2)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
@@ -177,6 +214,7 @@ GEM
     tilt (2.0.9)
     tzinfo (1.2.5)
       thread_safe (~> 0.1)
+    vcr (4.0.0)
     warden (1.2.7)
       rack (>= 1.0)
     webmock (3.4.2)
@@ -195,16 +233,21 @@ DEPENDENCIES
   coffee-rails
   database_cleaner
   devise
+  google-cloud-translate (~> 1.2.4)
   jquery-rails
   lit!
+  minitest (~> 5.11.3)
+  minitest-vcr (~> 1.4.0)
   mocha
   pg (~> 0.18.4)
+  pry-byebug (~> 3.6.0)
   pry-rails
   rails (~> 4.2.0)
   redis
   sass-rails
   test_after_commit
   test_declarative
+  vcr (~> 4.0.0)
   webmock
 
 BUNDLED WITH