Merge pull request #444 from aew/master

Set :en as fallback locale for grape errors when translations are missin...

Author: dblock

CHANGELOG.md

@@ -6,6 +6,7 @@ Next Release
 * Grape is no longer tested against Ruby 1.8.7.
 * [#442](https://github.com/intridea/grape/issues/442): Enable incrementally building on top of a previous API version - [@dblock](https://github.com/dblock).
 * [#442](https://github.com/intridea/grape/issues/442): API `version` can now take an array of multiple versions - [@dblock](https://github.com/dblock).
+* [#444](https://github.com/intridea/grape/issues/444): Added :en as fallback locale for I18n - [@aew](https://github.com/aew).
 
 * Your contribution here.
 

README.md

@@ -430,6 +430,12 @@ rescue_from Grape::Exceptions::Validation do |e|
 end
 ```
 
+### I18n
+
+Grape supports I18n for parameter-related error messages, but will fallback to English if 
+translations for the default locale have not been provided. See [en.yml](lib/grape/locale/en.yml) for message keys.
+
+
 ## Headers
 
 Request headers are available through the `headers` helper or from `env` in their original form.

lib/grape/exceptions/base.rb

@@ -4,6 +4,7 @@ class Base < StandardError
 
       BASE_MESSAGES_KEY = 'grape.errors.messages'
       BASE_ATTRIBUTES_KEY = 'grape.errors.attributes'
+      FALLBACK_LOCALE = :en
 
       attr_reader :status, :message, :headers
 
@@ -58,7 +59,8 @@ def translate_message(key, options = {})
       end
 
       def translate(key, options = {})
-        ::I18n.translate(key, options)
+        message = ::I18n.translate(key, options)
+        message.present? ? message : ::I18n.translate(key, options.merge({:locale => FALLBACK_LOCALE}))
       end
 
     end

spec/grape/validations/coerce_spec.rb

@@ -6,19 +6,37 @@
   def app; subject end
 
   describe 'coerce' do
-    it "i18n error on malformed input" do
-      I18n.load_path << File.expand_path('../zh-CN.yml',__FILE__)
-      I18n.reload!
-      I18n.locale = :'zh-CN'
-      subject.params { requires :age, :type => Integer }
-      subject.get '/single' do 'int works'; end
+    
+    context "i18n" do
+    
+      after :each do
+        I18n.locale = :en
+      end
+    
+      it "i18n error on malformed input" do
+        I18n.load_path << File.expand_path('../zh-CN.yml',__FILE__)
+        I18n.reload!
+        I18n.locale = :'zh-CN'
+        subject.params { requires :age, :type => Integer }
+        subject.get '/single' do 'int works'; end
+
+        get '/single', :age => '43a'
+        last_response.status.should == 400
+        last_response.body.should == '年龄格式不正确'
+      end
+    
+      it 'gives an english fallback error when default locale message is blank' do
+        I18n.locale = :'pt-BR'
+        subject.params { requires :age, :type => Integer }
+        subject.get '/single' do 'int works'; end
 
-      get '/single', :age => '43a'
-      last_response.status.should == 400
-      last_response.body.should == '年龄格式不正确'
-      I18n.locale = :en
+        get '/single', :age => '43a'
+        last_response.status.should == 400
+        last_response.body.should == 'invalid parameter: age'
+      end
 
     end
+    
     it 'error on malformed input' do
       subject.params { requires :int, :type => Integer }
       subject.get '/single' do 'int works'; end