Fetch GH PR source refs in bulkfix/speed-gh-pr-import

3 files changed, 18 insertions, 3 deletions

diff --git a/app/models/repository.rb b/app/models/repository.rb
index 6ab04440ca8..840ad386875 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -1032,6 +1032,11 @@ class Repository
     Gitlab::Popen.popen(args, path_to_repo)
   end
 
+  def fetch_refs(source_path, refspecs)
+    args = %W(#{Gitlab.config.git.bin_path} fetch --no-tags -f #{source_path}) +  refspecs
+    Gitlab::Popen.popen(args, path_to_repo)
+  end
+
   def create_ref(ref, ref_path)
     fetch_ref(path_to_repo, ref, ref_path)
   end
diff --git a/lib/gitlab/github_import/importer.rb b/lib/gitlab/github_import/importer.rb
index eea4a91f17d..0c7c9327c50 100644
--- a/lib/gitlab/github_import/importer.rb
+++ b/lib/gitlab/github_import/importer.rb
@@ -130,13 +130,23 @@ module Gitlab
 
       def import_pull_requests
         fetch_resources(:pull_requests, repo, state: :all, sort: :created, direction: :asc, per_page: 100) do |pull_requests|
+          project.repository.expire_branches_cache
+
+          refspecs = pull_requests.map do |raw|
+            gh_pull_request = PullRequestFormatter.new(project, raw, client)
+            next if gh_pull_request.source_branch_exists?
+
+            "pull/#{gh_pull_request.number}/head:#{gh_pull_request.source_branch_name}"
+          end
+
+          project.repository.fetch_refs(repo_url, refspecs.compact)
+
           pull_requests.each do |raw|
             gh_pull_request = PullRequestFormatter.new(project, raw, client)
 
             next unless gh_pull_request.valid?
 
             begin
-              restore_source_branch(gh_pull_request) unless gh_pull_request.source_branch_exists?
               restore_target_branch(gh_pull_request) unless gh_pull_request.target_branch_exists?
 
               merge_request = gh_pull_request.create!
diff --git a/lib/gitlab/github_import/pull_request_formatter.rb b/lib/gitlab/github_import/pull_request_formatter.rb
index add7236e339..ed90c3617fd 100644
--- a/lib/gitlab/github_import/pull_request_formatter.rb
+++ b/lib/gitlab/github_import/pull_request_formatter.rb
@@ -39,7 +39,7 @@ module Gitlab
       def source_branch_name
         @source_branch_name ||= begin
           if cross_project?
-            "pull/#{number}/#{source_branch_repo.full_name}/#{source_branch_ref}"
+            "pull-source/#{number}/#{source_branch_repo.full_name}/#{source_branch_ref}"
           else
             source_branch_exists? ? source_branch_ref : "pull/#{number}/#{source_branch_ref}"
           end
@@ -52,7 +52,7 @@ module Gitlab
 
       def target_branch_name
         @target_branch_name ||= begin
-          target_branch_exists? ? target_branch_ref : "pull/#{number}/#{target_branch_ref}"
+          target_branch_exists? ? target_branch_ref : "pull-target/#{number}/#{target_branch_ref}"
         end
       end