Fix bug for repeated fork requests

When asking to fork a project and a project with the same name
already exists (likely from a previous fork), the recovery from
the fork failure would inadvertantly delete the repo of the
existing destination project.

1 files changed, 25 insertions, 17 deletions

diff --git a/app/contexts/projects/fork_context.rb b/app/contexts/projects/fork_context.rb
index e206a1cdf87..f2a0684b01c 100644
--- a/app/contexts/projects/fork_context.rb
+++ b/app/contexts/projects/fork_context.rb
@@ -10,28 +10,36 @@ module Projects
       project = Project.new
       project.initialize_dup(@from_project)
       project.name = @from_project.name
-      project.path = @from_project.path 
+      project.path = @from_project.path
       project.namespace = current_user.namespace
+      project.creator = current_user
 
-      Project.transaction do
-        #First save the DB entries as they can be rolled back if the repo fork fails
-        project.creator = current_user
-        project.build_forked_project_link(forked_to_project_id: project.id, forked_from_project_id: @from_project.id)
-        if project.save
-          project.users_projects.create(project_access: UsersProject::MASTER, user: current_user)
+      # If the project cannot save, we do not want to trigger the project destroy
+      # as this can have the side effect of deleting a repo attached to an existing
+      # project with the same name and namespace
+      if project.valid?
+        begin
+          Project.transaction do
+            #First save the DB entries as they can be rolled back if the repo fork fails
+            project.build_forked_project_link(forked_to_project_id: project.id, forked_from_project_id: @from_project.id)
+            if project.save
+              project.users_projects.create(project_access: UsersProject::MASTER, user: current_user)
+            end
+            #Now fork the repo
+            unless gitlab_shell.fork_repository(@from_project.path_with_namespace, project.namespace.path)
+              raise "forking failed in gitlab-shell"
+            end
+            project.ensure_satellite_exists
+          end
+        rescue => ex
+          project.errors.add(:base, "Fork transaction failed.")
+          project.destroy
         end
-        #Now fork the repo
-        unless gitlab_shell.fork_repository(@from_project.path_with_namespace, project.namespace.path)
-          raise "forking failed in gitlab-shell"
-        end
-        project.ensure_satellite_exists
-
+      else
+        project.errors.add(:base, "Invalid fork destination")
       end
       project
-    rescue => ex
-      project.errors.add(:base, "Can't fork project. Please try again later")
-      project.destroy
-    end
 
+    end
   end
 end