Look for .gitlab-ci.yml only if checkout_sha is present

app/models/project_services/gitlab_ci_service.rb

@@ -40,10 +40,14 @@ class GitlabCiService < CiService
   def execute(data)
     return unless supported_events.include?(data[:object_kind])
 
-    ci_yaml_file = ci_yaml_file(data)
+    sha = data[:checkout_sha]
 
-    if ci_yaml_file
-      data.merge!(ci_yaml_file: ci_yaml_file)
+    if sha.present?
+      file = ci_yaml_file(sha)
+
+      if file && file.data
+        data.merge!(ci_yaml_file: file.data)
+      end
     end
 
     service_hook.execute(data)
@@ -129,15 +133,15 @@ class GitlabCiService < CiService
 
   private
 
-  def ci_yaml_file(data)
-    ref = data[:checkout_sha]
-    repo = project.repository
-    commit = repo.commit(ref)
-    blob = Gitlab::Git::Blob.find(repo, commit.id, ".gitlab-ci.yml")
-    blob && blob.data
+  def ci_yaml_file(sha)
+    repository.blob_at(sha, '.gitlab-ci.yml')
   end
 
   def fork_registration_path
     project_url.sub(/projects\/\d*/, "#{API_PREFIX}/forks")
   end
+
+  def repository
+    project.repository
+  end
 end

spec/models/project_services/gitlab_ci_service_spec.rb

@@ -58,7 +58,7 @@ describe GitlabCiService do
         service_hook = double
         service_hook.should_receive(:execute)
         @service.should_receive(:service_hook).and_return(service_hook)
-        @service.should_receive(:ci_yaml_file).with(push_sample_data)
+        @service.should_receive(:ci_yaml_file).with(push_sample_data[:checkout_sha])
 
         @service.execute(push_sample_data)
       end