Merge branch 'zj-workhorse-to-serve-diffs' into 'master' 14722-searching-for-usernames-should-only-be-possible-for-search-strings-with-a-valid-format

Workhorse to serve raw diffs

Fixes (partially) #13999

Dependent on: gitlab-org/gitlab-workhorse!45

See merge request !4130

7 files changed, 30 insertions, 31 deletions

diff --git a/CHANGELOG b/CHANGELOG
index dbaa396143f..ce8f2823c25 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -172,6 +172,7 @@ v 8.7.6
   - Fix import from GitLab.com to a private instance failure. !4181
   - Fix external imports not finding the import data. !4106
   - Fix notification delay when changing status of an issue
+  - Bump Workhorse to 0.7.5 so it can serve raw diffs
 
 v 8.7.5
   - Fix relative links in wiki pages. !4050
diff --git a/GITLAB_WORKHORSE_VERSION b/GITLAB_WORKHORSE_VERSION
index 0a1ffad4b4d..8bd6ba8c5c3 100644
--- a/GITLAB_WORKHORSE_VERSION
+++ b/GITLAB_WORKHORSE_VERSION
@@ -1 +1 @@
-0.7.4
+0.7.5
diff --git a/app/controllers/projects/merge_requests_controller.rb b/app/controllers/projects/merge_requests_controller.rb
index 0de34420883..06a114dcbe8 100644
--- a/app/controllers/projects/merge_requests_controller.rb
+++ b/app/controllers/projects/merge_requests_controller.rb
@@ -58,9 +58,16 @@ class Projects::MergeRequestsController < Projects::ApplicationController
 
     respond_to do |format|
       format.html
-      format.json { render json: @merge_request }
-      format.diff { render text: @merge_request.to_diff }
-      format.patch { render text: @merge_request.to_patch }
+      format.json   { render json: @merge_request }
+      format.patch  { render text: @merge_request.to_patch }
+      format.diff do
+        headers.store(*Gitlab::Workhorse.send_git_diff(@project.repository,
+                                                        @merge_request.diff_base_commit.id,
+                                                        @merge_request.last_commit.id))
+        headers['Content-Disposition'] = 'inline'
+
+        head :ok
+      end
     end
   end
 
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 6c7668778ba..b0ed8182855 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -313,13 +313,6 @@ class MergeRequest < ActiveRecord::Base
     )
   end
 
-  # Returns the raw diff for this merge request
-  #
-  # see "git diff"
-  def to_diff
-    target_project.repository.diff_text(diff_base_commit.sha, source_sha)
-  end
-
   # Returns the commit as a series of email patches.
   #
   # see "git format-patch"
diff --git a/features/project/merge_requests.feature b/features/project/merge_requests.feature
index 396eb7cc11b..0e97e4d5954 100644
--- a/features/project/merge_requests.feature
+++ b/features/project/merge_requests.feature
@@ -74,18 +74,6 @@ Feature: Project Merge Requests
     And I submit new merge request "Wiki Feature"
     Then I should see merge request "Wiki Feature"
 
-  Scenario: I download a diff on a public merge request
-    Given public project "Community"
-    And "John Doe" owns public project "Community"
-    And project "Community" has "Bug CO-01" open merge request with diffs inside
-    Given I logout directly
-    And I visit merge request page "Bug CO-01"
-    And I click on "Email Patches"
-    Then I should see a patch diff
-    And I visit merge request page "Bug CO-01"
-    And I click on "Plain Diff"
-    Then I should see a patch diff
-
   @javascript
   Scenario: I comment on a merge request
     Given I visit merge request page "Bug NS-04"
diff --git a/lib/gitlab/workhorse.rb b/lib/gitlab/workhorse.rb
index c3ddd4c2680..7f6ef71b303 100644
--- a/lib/gitlab/workhorse.rb
+++ b/lib/gitlab/workhorse.rb
@@ -29,9 +29,22 @@ module Gitlab
           "git-archive:#{encode(params)}",
         ]
       end
-      
+
+      def send_git_diff(repository, from, to)
+        params = {
+            'RepoPath'  => repository.path_to_repo,
+            'ShaFrom'   => from,
+            'ShaTo'     => to
+        }
+
+        [
+          SEND_DATA_HEADER,
+          "git-diff:#{encode(params)}"
+        ]
+      end
+
       protected
-      
+
       def encode(hash)
         Base64.urlsafe_encode64(JSON.dump(hash))
       end
diff --git a/spec/controllers/projects/merge_requests_controller_spec.rb b/spec/controllers/projects/merge_requests_controller_spec.rb
index 2a9ee881e98..1301574f489 100644
--- a/spec/controllers/projects/merge_requests_controller_spec.rb
+++ b/spec/controllers/projects/merge_requests_controller_spec.rb
@@ -84,17 +84,14 @@ describe Projects::MergeRequestsController do
     end
 
     describe "as diff" do
-      include_examples "export merge as", :diff
-      let(:format) { :diff }
-
-      it "should really only be a git diff" do
+      it "triggers workhorse to serve the request" do
         get(:show,
             namespace_id: project.namespace.to_param,
             project_id: project.to_param,
             id: merge_request.iid,
-            format: format)
+            format: :diff)
 
-        expect(response.body).to start_with("diff --git")
+        expect(response.headers['Gitlab-Workhorse-Send-Data']).to start_with("git-diff:")
       end
     end