Merge branch 'sh-fix-create-projects-with-prometheus-service' into 'master'

Fix errors creating project with active Prometheus service template

Closes #212419

See merge request gitlab-org/gitlab!30340

app/services/projects/create_service.rb

@@ -173,6 +173,10 @@ module Projects
     def create_prometheus_service
       service = @project.find_or_initialize_service(::PrometheusService.to_param)
 
+      # If the service has already been inserted in the database, that
+      # means it came from a template, and there's nothing more to do.
+      return if service.persisted?
+
       if service.prometheus_available?
         service.save!
       else

changelogs/unreleased/sh-fix-create-projects-with-prometheus-service.yml

+---
+title: Fix errors creating project with active Prometheus service template
+merge_request: 30340
+author:
+type: fixed

spec/services/projects/create_service_spec.rb

@@ -348,6 +348,7 @@ describe Projects::CreateService, '#execute' do
       project = create_project(user, opts)
 
       expect(project.services.count).to eq 1
+      expect(project.errors).to be_empty
     end
   end