Add container repository create service with specs

app/models/container_repository.rb

@@ -58,4 +58,8 @@ class ContainerRepository < ActiveRecord::Base
       client.delete_repository_tag(self.path, digest)
     end
   end
+
+  def self.create_from_path(path)
+    self.create(project: path.repository_project, name: path.repository_name)
+  end
 end

app/services/container_registry/create_repository_service.rb

+module ContainerRegistry
+  ##
+  # Service for creating a container repository.
+  #
+  # It is usually executed before registry authenticator returns
+  # a token for given request.
+  #
+  class CreateRepositoryService < BaseService
+    def execute(path)
+      @path = path
+
+      return if path.has_repository?
+
+      unless user_can_create? || legacy_trigger_can_create?
+        raise Gitlab::Access::AccessDeniedError
+      end
+
+      ContainerRepository.create_from_path(path)
+    end
+
+    private
+
+    def user_can_create?
+      can?(@current_user, :create_container_image, @path.repository_project)
+    end
+
+    ## TODO, remove it after removing legacy triggers.
+    #
+    def legacy_trigger_can_create?
+      @current_user.nil? && @project == @path.repository_project
+    end
+  end
+end

spec/services/container_registry/create_repository_service_spec.rb

+require 'spec_helper'
+
+describe ContainerRegistry::CreateRepositoryService, '#execute' do
+  let(:project) { create(:empty_project) }
+  let(:user) { create(:user) }
+
+  let(:path) do
+    ContainerRegistry::Path.new("#{project.full_path}/my/image")
+  end
+
+  let(:service) { described_class.new(project, user) }
+
+  before do
+    stub_container_registry_config(enabled: true)
+  end
+
+  context 'when container repository already exists' do
+    before do
+      create(:container_repository, project: project, name: 'my/image')
+    end
+
+    it 'does not create container repository again' do
+      expect { service.execute(path) }
+        .to raise_error(Gitlab::Access::AccessDeniedError)
+        .and change { ContainerRepository.count }.by(0)
+    end
+  end
+
+  context 'when repository is created by an user' do
+    context 'when user has no ability to create a repository' do
+      it 'does not create a new container repository' do
+        expect { service.execute(path) }
+          .to raise_error(Gitlab::Access::AccessDeniedError)
+          .and change { ContainerRepository.count }.by(0)
+      end
+    end
+
+    context 'when user has ability do create a repository' do
+      before do
+        project.add_developer(user)
+      end
+
+      it 'creates a new container repository' do
+        expect { service.execute(path) }
+          .to change { project.container_repositories.count }.by(1)
+      end
+    end
+  end
+
+  context 'when repository is created by a legacy pipeline trigger' do
+    let(:user) { nil }
+
+    context 'when repository path matches authenticated project' do
+      it 'creates a new container repository' do
+        expect { service.execute(path) }
+          .to change { project.container_repositories.count }.by(1)
+      end
+    end
+
+    context 'when repository path does not match authenticated project' do
+      let(:private_project) { create(:empty_project, :private) }
+
+      let(:path) do
+        ContainerRegistry::Path.new("#{private_project.full_path}/my/image")
+      end
+
+      it 'does not create a new container repository' do
+        expect { service.execute(path) }
+          .to raise_error(Gitlab::Access::AccessDeniedError)
+          .and change { ContainerRepository.count }.by(0)
+      end
+    end
+  end
+end