[api] Fix view=blame for attributes

by forwarding also the view parameter to the backend.

This was necessary as the API was not delivering what it was
supposed to do with a view parameter.
This was especially important for the standard blame view.

src/api/app/controllers/attribute_controller.rb

@@ -182,9 +182,9 @@ def show_attribute
     # init
     # checks
     # exec
-    if params[:rev] || @attribute_container.nil?
+    if params[:rev] || params[:meta] || params[:view] || @attribute_container.nil?
       # old or remote instance entry
-      render xml: Backend::Api::Sources::Package.attributes(params[:project], params[:package], params[:rev])
+      render xml: Backend::Api::Sources::Package.attributes(params[:project], params[:package], params)
       return
     end
 

src/api/lib/backend/api/sources/package.rb

@@ -8,10 +8,12 @@ module Package
         # Returns the attributes content
         # @param revision [String] Revision hash/number.
         # @return [String]
-        def self.attributes(project_name, package_name, revision)
+        def self.attributes(project_name, package_name, options = {})
           params = { meta: 1 }
-          params[:rev] = revision if revision
-          http_get(['/source/:project/:package/_attribute', project_name, package_name || '_project'], params: params)
+          params[:rev]  = options[:rev]  if options[:rev]
+          params[:view] = options[:view] if options[:view]
+          http_get(['/source/:project/:package/_attribute', project_name, package_name || '_project'],
+                   params: params, accepted: [:rev, :meta, :view])
         end
 
         # Writes the content in xml for attributes

src/api/test/functional/attributes_test.rb

@@ -150,6 +150,11 @@ def test_create_type
     assert_response :success
     assert_xml_tag tag: 'value', content: 'A'
     assert_xml_tag tag: 'value', content: 'B'
+    # blame view is working
+    get '/source/home:adrian/_project/_attribute?view=blame&meta=1'
+    assert_response :success
+    assert_match(/^   . \(adrian/, @response.body)
+
     # cleanup
     login_Iggy
     delete '/attribute/TEST/Dummy/_meta'