Speed up project creation for users with many projects

When a user creates a project in a group, we refresh the
`authorized_projects` table for all members of that group using Sidekiq.
This includes the user that created the project, but that alone would
mean that if the Sidekiq job didn't finish almost immediately, a user
could create a project that they'd be unable to see for a few seconds.

We solved this by immediately refreshing all the projects for the user
who created the project. However, that in turn can be quite slow,
because we need to recompute the entire project authorization structure
for a user.

This commit changes that to just insert a single row to
`authorized_projects` for the user who created the project. It should be
accurate all the time, but if it is not quite right, the Sidekiq job
will correct it shortly after anyway.

app/services/projects/create_service.rb

@@ -107,12 +107,13 @@ module Projects
       create_readme if @initialize_with_readme
     end
 
-    # Refresh the current user's authorizations inline (so they can access the
-    # project immediately after this request completes), and any other affected
-    # users in the background
+    # Add an authorization for the current user authorizations inline
+    # (so they can access the project immediately after this request
+    # completes), and any other affected users in the background
     def setup_authorizations
       if @project.group
-        current_user.refresh_authorized_projects
+        current_user.project_authorizations.create!(project: @project,
+                                                    access_level: @project.group.max_member_access_for_user(current_user))
 
         if Feature.enabled?(:specialized_project_authorization_workers)
           AuthorizedProjectUpdate::ProjectCreateWorker.perform_async(@project.id)

changelogs/unreleased/insert-project-authorization-directly-when-creating-project.yml

+---
+title: Speed up project creation for users with many projects
+merge_request:
+author:
+type: performance

spec/services/projects/create_service_spec.rb

@@ -676,10 +676,6 @@ RSpec.describe Projects::CreateService, '#execute' do
     end
 
     it 'updates authorization for current_user' do
-      expect(Users::RefreshAuthorizedProjectsService).to(
-        receive(:new).with(user).and_call_original
-      )
-
       project = create_project(user, opts)
 
       expect(
@@ -711,10 +707,6 @@ RSpec.describe Projects::CreateService, '#execute' do
       end
 
       it 'updates authorization for current_user' do
-        expect(Users::RefreshAuthorizedProjectsService).to(
-          receive(:new).with(user).and_call_original
-        )
-
         project = create_project(user, opts)
 
         expect(