Localize error messages in API V3

lib/api/errors/conflict.rb

@@ -31,7 +31,7 @@ module API
   module Errors
     class Conflict < ErrorBase
       def initialize
-        super 409, 'Couldn\'t update the resource because of conflicting modifications.'
+        super 409, I18n.t('api_v3.errors.code_409')
       end
     end
   end

lib/api/errors/form/invalid_resource_link.rb

@@ -32,10 +32,13 @@ module API
     module Form
       class InvalidResourceLink < StandardError
         def initialize(property, expected_resource, actual_resource = :unknown)
-          expected = expected_resource.to_s.singularize.capitalize
-          actual = actual_resource.to_s.singularize.capitalize
-          message = "For property #{property} a resource of type #{expected}" \
-                    " is expected but got a resource of type #{actual}"
+          property_localized = I18n.t("attributes.#{property}")
+          expected_localized = I18n.t("attributes.#{expected_resource.to_s.singularize}")
+          actual_localized = I18n.t("attributes.#{actual_resource.to_s.singularize}")
+          message = I18n.t('api_v3.errors.invalid_resource',
+                           property: property_localized,
+                           expected: expected_localized,
+                           actual: actual_localized)
 
           super(message)
         end

lib/api/errors/parse_error.rb

@@ -31,7 +31,7 @@ module API
   module Errors
     class ParseError < InvalidRequestBody
       def initialize(message)
-        super 'The request body was neither empty, nor did it contain a single JSON object.'
+        super I18n.t('api_v3.errors.parse_error')
 
         @details = { parseError: clean_parse_error(message) }
       end

lib/api/errors/unauthenticated.rb

@@ -31,7 +31,7 @@ module API
   module Errors
     class Unauthenticated < ErrorBase
       def initialize
-        super 401, 'You need to be authenticated to access this resource.'
+        super 401, I18n.t('api_v3.errors.code_401')
       end
     end
   end

lib/api/errors/unauthorized.rb

@@ -31,7 +31,7 @@ module API
   module Errors
     class Unauthorized < ErrorBase
       def initialize
-        super 403, 'You are not authorized to access this resource.'
+        super 403, I18n.t('api_v3.errors.code_403')
       end
     end
   end

lib/api/errors/unwritable_property.rb

@@ -35,7 +35,13 @@ module API
 
         fail ArgumentError, 'UnwritableProperty error must contain at least one invalid attribute!' if attributes.empty?
 
-        super 422, 'You must not write a read-only attribute.'
+        if attributes.length == 1
+          message = I18n.t('api_v3.errors.writing_read_only_attributes')
+        else
+          message = I18n.t('api_v3.errors.multiple_errors')
+        end
+
+        super 422, message
 
         if attributes.length > 1
           invalid_attributes.each do |attribute|

lib/api/errors/validation.rb

@@ -32,8 +32,11 @@ module API
     class Validation < ErrorBase
       def initialize(obj)
         messages = obj.respond_to?(:errors) ? obj.errors.full_messages : Array(obj)
+        message = I18n.t('api_v3.errors.multiple_errors')
 
-        super 422, (messages.length == 1) ? messages[0] + '.' : 'Multiple fields violated their constraints.'
+        message = messages[0] + '.' if messages.length == 1
+
+        super 422, message
 
         messages.each { |m| @errors << Validation.new(m) } if messages.length > 1
       end

lib/api/v3/render/render_api.rb

@@ -43,7 +43,9 @@ module API
               actual = request.content_type
 
               unless actual.starts_with? SUPPORTED_MEDIA_TYPE
-                message = "Expected content type '#{SUPPORTED_MEDIA_TYPE}' but got '#{actual}'."
+                message = I18n.t('api_v3.errors.invalid_content_type',
+                                 content_type: SUPPORTED_MEDIA_TYPE,
+                                 actual: actual)
 
                 fail API::Errors::InvalidRequestBody, message
               end
@@ -61,7 +63,9 @@ module API
             def context_object
               try_context_object
             rescue ::ActiveRecord::RecordNotFound
-              fail API::Errors::InvalidRenderContext.new('Context does not exist!')
+              fail API::Errors::InvalidRenderContext.new(
+                I18n.t('api_v3.errors.render.context_object_not_found')
+              )
             end
 
             def try_context_object
@@ -79,9 +83,13 @@ module API
               context = ::API::V3::Utilities::ResourceLinkParser.parse(params[:context])
 
               if context.nil?
-                fail API::Errors::InvalidRenderContext.new('No context found.')
+                fail API::Errors::InvalidRenderContext.new(
+                  I18n.t('api_v3.errors.render.context_not_found')
+                )
               elsif !SUPPORTED_CONTEXT_NAMESPACES.include? context[:ns]
-                fail API::Errors::InvalidRenderContext.new('Unsupported context found.')
+                fail API::Errors::InvalidRenderContext.new(
+                  I18n.t('api_v3.errors.render.unsupported_context')
+                )
               else
                 context
               end