Add backend support for selecting custom templates by ID

This is the first step to fixing
https://gitlab.com/gitlab-org/gitlab/issues/9146 and adds the backend
support in https://gitlab.com/gitlab-org/gitlab/merge_requests/17205.

The backend support is added first to avoid no-downtime issues with
creating new projects.

app/controllers/projects_controller.rb

@@ -376,6 +376,7 @@ class ProjectsController < Projects::ApplicationController
       :tag_list,
       :visibility_level,
       :template_name,
+      :template_project_id,
       :merge_method,
       :initialize_with_readme,
 

app/services/projects/create_from_template_service.rb

@@ -4,8 +4,11 @@ module Projects
   class CreateFromTemplateService < BaseService
     include Gitlab::Utils::StrongMemoize
 
+    attr_reader :template_name
+
     def initialize(user, params)
       @current_user, @params = user, params.to_h.dup
+      @template_name = @params.delete(:template_name).presence
     end
 
     def execute
@@ -21,12 +24,6 @@ module Projects
       file&.close
     end
 
-    def template_name
-      strong_memoize(:template_name) do
-        params.delete(:template_name).presence
-      end
-    end
-
     private
 
     def validate_template!

app/services/projects/create_service.rb

@@ -13,7 +13,7 @@ module Projects
     end
 
     def execute
-      if @params[:template_name].present?
+      if create_from_template?
         return ::Projects::CreateFromTemplateService.new(current_user, params).execute
       end
 
@@ -184,6 +184,10 @@ module Projects
 
     private
 
+    def create_from_template?
+      @params[:template_name].present? || @params[:template_project_id].present?
+    end
+
     def import_schedule
       if @project.errors.empty?
         @project.import_state.schedule if @project.import? && !@project.bare_repository_import?

changelogs/unreleased/sh-use-template-project-id-backend.yml

+---
+title: Add backend support for selecting custom templates by ID
+merge_request: 18178
+author:
+type: fixed

ee/app/models/ee/user.rb

@@ -182,12 +182,20 @@ module EE
       email_opted_in_source_id == EMAIL_OPT_IN_SOURCE_ID_GITLAB_COM ? 'GitLab.com' : ''
     end
 
-    def available_custom_project_templates(search: nil, subgroup_id: nil)
+    def available_custom_project_templates(search: nil, subgroup_id: nil, project_id: nil)
       templates = ::Gitlab::CurrentSettings.available_custom_project_templates(subgroup_id)
 
+      params = {}
+
+      if project_id
+        templates = templates.where(id: project_id)
+      else
+        params = { search: search, sort: 'name_asc' }
+      end
+
       ::ProjectsFinder.new(current_user: self,
                            project_ids_relation: templates,
-                           params: { search: search, sort: 'name_asc' })
+                           params: params)
                       .execute
     end
 

ee/app/services/ee/projects/create_from_template_service.rb

@@ -6,6 +6,16 @@ module EE
       extend ::Gitlab::Utils::Override
       include ::Gitlab::Utils::StrongMemoize
 
+      attr_reader :template_project_id, :subgroup_id
+
+      override :initialize
+      def initialize(user, params)
+        super
+
+        @template_project_id = @params.delete(:template_project_id).to_i if @params[:template_project_id].present?
+        @subgroup_id = @params.delete(:group_with_project_templates_id).presence
+      end
+
       override :execute
       def execute
         return super unless use_custom_template?
@@ -27,13 +37,19 @@ module EE
 
         return true if template_project.present?
 
-        project.errors.add(:template_name, _("'%{template_name}' is unknown or invalid" % { template_name: template_name }))
+        if template_project_id.present?
+          project.errors.add(:template_project_id,
+                             _("%{template_project_id} is unknown or invalid" % { template_project_id: template_project_id }))
+        else
+          project.errors.add(:template_name, _("'%{template_name}' is unknown or invalid" % { template_name: template_name }))
+        end
+
         false
       end
 
       def use_custom_template?
         strong_memoize(:use_custom_template) do
-          template_name &&
+          template_requested? &&
             ::Gitlab::Utils.to_boolean(params.delete(:use_custom_template)) &&
             ::Gitlab::CurrentSettings.custom_project_templates_enabled?
         end
@@ -41,13 +57,19 @@ module EE
 
       def template_project
         strong_memoize(:template_project) do
-          current_user.available_custom_project_templates(search: template_name, subgroup_id: subgroup_id)
-                      .first
+          templates =
+            if template_project_id.present?
+              current_user.available_custom_project_templates(project_id: template_project_id, subgroup_id: subgroup_id)
+            else
+              current_user.available_custom_project_templates(search: template_name, subgroup_id: subgroup_id)
+            end
+
+          templates.first
         end
       end
 
-      def subgroup_id
-        @subgroup_id ||= params.delete(:group_with_project_templates_id).presence
+      def template_requested?
+        template_name.present? || template_project_id.is_a?(Integer)
       end
 
       # rubocop: disable CodeReuse/ActiveRecord

ee/app/services/ee/projects/create_service.rb

@@ -12,7 +12,7 @@ module EE
         mirror_user_id = current_user.id if mirror
         mirror_trigger_builds = params.delete(:mirror_trigger_builds)
         ci_cd_only = ::Gitlab::Utils.to_boolean(params.delete(:ci_cd_only))
-        group_with_project_templates_id = params.delete(:group_with_project_templates_id) if params[:template_name].blank?
+        group_with_project_templates_id = params.delete(:group_with_project_templates_id) if params[:template_name].blank? && params[:template_project_id].blank?
 
         project = super do |project|
           # Repository size limit comes as MB from the view

ee/spec/models/user_spec.rb

@@ -302,6 +302,7 @@ describe User do
         let!(:private_project) { create :project, :private, namespace: group, name: 'private_project' }
         let!(:internal_project) { create :project, :internal, namespace: group, name: 'internal_project' }
         let!(:public_project) { create :project, :public, namespace: group, name: 'public_project' }
+        let!(:public_project_two) { create :project, :public, namespace: group, name: 'public_project_second' }
 
         it 'returns public projects' do
           expect(user.available_custom_project_templates).to include public_project
@@ -332,9 +333,27 @@ describe User do
         it 'allows to search available project templates by name' do
           projects = user.available_custom_project_templates(search: 'publi')
 
-          expect(projects.count).to eq 1
+          expect(projects.count).to eq 2
           expect(projects.first).to eq public_project
         end
+
+        it 'filters by project ID' do
+          projects = user.available_custom_project_templates(project_id: public_project.id)
+
+          expect(projects.count).to eq 1
+          expect(projects).to match_array([public_project])
+
+          projects = user.available_custom_project_templates(project_id: [public_project.id, public_project_two.id])
+
+          expect(projects.count).to eq 2
+          expect(projects).to match_array([public_project, public_project_two])
+        end
+
+        it 'does not return inaccessible projects' do
+          projects = user.available_custom_project_templates(project_id: private_project.id)
+
+          expect(projects.count).to eq 0
+        end
       end
     end
   end

ee/spec/services/projects/create_from_template_service_spec.rb

@@ -16,8 +16,10 @@ require 'spec_helper'
 # Group 2
 
 describe Projects::CreateFromTemplateService do
+  using RSpec::Parameterized::TableSyntax
+
   let(:group) { create(:group) }
-  let(:project) { create(:project, :public, namespace: group) }
+  let!(:project) { create(:project, :public, namespace: group) }
   let(:user) { create(:user) }
   let(:project_name) { project.name }
   let(:use_custom_template) { true }
@@ -30,13 +32,14 @@ describe Projects::CreateFromTemplateService do
   let(:subgroup_2) { create(:group, parent: group) }
   let(:subgroup_2_1) { create(:group, parent: subgroup_2) }
   let(:project_template) { create(:project, :public, namespace: subgroup_1_2) }
+  let(:template_name) { project_template.name }
   let(:namespace_id) { nil }
   let(:group_with_project_templates_id) { nil }
 
   let(:project_params) do
     {
       path: user.to_param,
-      template_name: project_name,
+      template_name: template_name,
       description: 'project description',
       visibility_level: Gitlab::VisibilityLevel::PUBLIC,
       use_custom_template: use_custom_template,
@@ -49,7 +52,7 @@ describe Projects::CreateFromTemplateService do
 
   before do
     stub_licensed_features(custom_project_templates: true)
-    stub_ee_application_setting(custom_project_templates_group_id: group.id)
+    stub_ee_application_setting(custom_project_templates_group_id: subgroup_1_2.id)
   end
 
   context '#execute' do
@@ -80,7 +83,7 @@ describe Projects::CreateFromTemplateService do
       end
 
       context 'when custom_project_template does not exist' do
-        let(:project_name) { 'whatever' }
+        let(:template_name) { 'whatever' }
 
         it 'does not attempt to import a project' do
           expect(::Projects::GitlabProjectsImportService).not_to receive(:new)
@@ -88,10 +91,18 @@ describe Projects::CreateFromTemplateService do
       end
     end
 
-    shared_examples 'creates project from custom template' do |subgroup_id|
-      # If we move the project inside a let block it throws a SEGFAULT error
+    where(:use_template_name) { [true, false] }
+
+    with_them do
       before do
-        project_params[:group_with_project_templates_id] = subgroup_id
+        if use_template_name
+          project_params[:template_name] = template_name
+          project_params.delete(:template_project_id)
+        else
+          project_params.delete(:template_name)
+          project_params[:template_project_id] = project_template.id
+        end
+
         @project = subject.execute
       end
 
@@ -109,97 +120,94 @@ describe Projects::CreateFromTemplateService do
           expect(@project.visibility_level).to eq(Gitlab::VisibilityLevel::PUBLIC)
         end
       end
-    end
 
-    it_behaves_like 'creates project from custom template', nil
-    it_behaves_like 'creates project from custom template', ''
+      describe 'creating project from a Group project template' do
+        let(:project_name) { project_template.name }
+        let(:group_with_project_templates_id) { subgroup_1_2.id }
+        let(:group2) { create(:group) }
 
-    describe 'creating project from a Group project template' do
-      let(:project_name) { project_template.name }
-      let(:group_with_project_templates_id) { subgroup_1_2.id }
-      let(:group2) { create(:group) }
-
-      before do
-        subgroup_1.update!(custom_project_templates_group_id: subgroup_1_2.id)
-        group.add_maintainer(user)
-        group2.add_maintainer(user)
-      end
+        before do
+          subgroup_1.update!(custom_project_templates_group_id: subgroup_1_2.id)
+          group.add_maintainer(user)
+          group2.add_maintainer(user)
+        end
 
-      shared_examples 'a persisted project' do
-        it "is persisted" do
-          project = subject.execute
+        shared_examples 'a persisted project' do
+          it "is persisted" do
+            project = subject.execute
 
-          expect(project).to be_saved
-          expect(project.import_scheduled?).to be(true)
+            expect(project).to be_saved
+            expect(project.import_scheduled?).to be(true)
+          end
         end
-      end
 
-      shared_examples 'a project that isn\'t persisted' do
-        it "isn't persisted" do
-          project = subject.execute
+        shared_examples 'a project that isn\'t persisted' do
+          it "isn't persisted" do
+            project = subject.execute
 
-          expect(project).not_to be_saved
-          expect(project.repository.empty?).to eq(true)
+            expect(project).not_to be_saved
+            expect(project.repository.empty?).to eq(true)
+          end
         end
-      end
 
-      context 'when the namespace is not a descendant of the Group owning the template' do
-        context 'when project is created under a group that is outside the hierarchy its root ancestor group' do
-          let(:namespace_id) { group2.id }
+        context 'when the namespace is not a descendant of the Group owning the template' do
+          context 'when project is created under a group that is outside the hierarchy its root ancestor group' do
+            let(:namespace_id) { group2.id }
 
-          it_behaves_like 'a project that isn\'t persisted'
-        end
+            it_behaves_like 'a project that isn\'t persisted'
+          end
 
-        context 'when project is created under a group that is a descendant of its root ancestor group' do
-          let(:namespace_id) { subgroup_2.id }
+          context 'when project is created under a group that is a descendant of its root ancestor group' do
+            let(:namespace_id) { subgroup_2.id }
 
-          it_behaves_like 'a project that isn\'t persisted'
-        end
+            it_behaves_like 'a project that isn\'t persisted'
+          end
 
-        context 'when project is created under a subgroup that is a descendant of its root ancestor group' do
-          let(:namespace_id) { subgroup_2_1.id }
+          context 'when project is created under a subgroup that is a descendant of its root ancestor group' do
+            let(:namespace_id) { subgroup_2_1.id }
 
-          it_behaves_like 'a project that isn\'t persisted'
-        end
+            it_behaves_like 'a project that isn\'t persisted'
+          end
 
-        context 'when project is created outside of group hierarchy' do
-          let(:user) { create(:user) }
-          let(:project) { create(:project, :public, namespace: user.namespace) }
-          let(:namespace_id) { user.namespace_id }
+          context 'when project is created outside of group hierarchy' do
+            let(:user) { create(:user) }
+            let(:project) { create(:project, :public, namespace: user.namespace) }
+            let(:namespace_id) { user.namespace_id }
 
-          it_behaves_like 'a project that isn\'t persisted'
+            it_behaves_like 'a project that isn\'t persisted'
+          end
         end
-      end
 
-      context 'when the namespace is inside the hierarchy of the Group owning the template' do
-        context 'when project is created under its parent group' do
-          let(:namespace_id) { subgroup_1.id }
+        context 'when the namespace is inside the hierarchy of the Group owning the template' do
+          context 'when project is created under its parent group' do
+            let(:namespace_id) { subgroup_1.id }
 
-          it_behaves_like 'a persisted project'
-        end
+            it_behaves_like 'a persisted project'
+          end
 
-        context 'when project is created under the same group' do
-          let(:namespace_id) { subgroup_1_2.id }
+          context 'when project is created under the same group' do
+            let(:namespace_id) { subgroup_1_2.id }
 
-          it_behaves_like 'a persisted project'
-        end
+            it_behaves_like 'a persisted project'
+          end
 
-        context 'when project is created under its descendant group' do
-          let(:namespace_id) { subgroup_1_2_1.id }
+          context 'when project is created under its descendant group' do
+            let(:namespace_id) { subgroup_1_2_1.id }
 
-          it_behaves_like 'a persisted project'
-        end
+            it_behaves_like 'a persisted project'
+          end
 
-        context 'when project is created under a group that is a descendant of its parent group' do
-          let(:namespace_id) { subgroup_1_1.id }
+          context 'when project is created under a group that is a descendant of its parent group' do
+            let(:namespace_id) { subgroup_1_1.id }
 
-          it_behaves_like 'a persisted project'
-        end
+            it_behaves_like 'a persisted project'
+          end
 
-        context 'when project is created under a subgroup that is a descendant of its parent group' do
-          let(:namespace_id) { subgroup_1_1_1.id }
+          context 'when project is created under a subgroup that is a descendant of its parent group' do
+            let(:namespace_id) { subgroup_1_1_1.id }
 
-          it_behaves_like 'a persisted project'
+            it_behaves_like 'a persisted project'
+          end
         end
       end
     end

ee/spec/services/projects/create_service_spec.rb

@@ -13,6 +13,20 @@ describe Projects::CreateService, '#execute' do
     }
   end
 
+  context 'with a template project ID' do
+    before do
+      opts.merge!(
+        template_project_id: 1
+      )
+    end
+
+    it 'creates a project using the template service' do
+      expect(::Projects::CreateFromTemplateService).to receive_message_chain(:new, :execute)
+
+      create_project(user, opts)
+    end
+  end
+
   context 'with a CI/CD only project' do
     before do
       opts.merge!(

locale/gitlab.pot

@@ -358,6 +358,9 @@ msgstr[1] ""
 msgid "%{tabname} changed"
 msgstr ""
 
+msgid "%{template_project_id} is unknown or invalid"
+msgstr ""
+
 msgid "%{text} %{files}"
 msgid_plural "%{text} %{files} files"
 msgstr[0] ""