Martin Brennan 60ad836313 DEV: Chat service object initial implementation (#19814) ... This is a combined work of Martin Brennan, Loïc Guitaut, and Joffrey Jaffeux. --- This commit implements a base service object when working in chat. The documentation is available at https://discourse.github.io/discourse/chat/backend/Chat/Service.html Generating documentation has been made as part of this commit with a bigger goal in mind of generally making it easier to dive into the chat project. Working with services generally involves 3 parts: - The service object itself, which is a series of steps where few of them are specialized (model, transaction, policy) ```ruby class UpdateAge include Chat::Service::Base model :user, :fetch_user policy :can_see_user contract step :update_age class Contract attribute :age, :integer end def fetch_user(user_id:, **) User.find_by(id: user_id) end def can_see_user(guardian:, **) guardian.can_see_user(user) end def update_age(age:, **) user.update!(age: age) end end ``` - The `with_service` controller helper, handling success and failure of the service within a service and making easy to return proper response to it from the controller ```ruby def update with_service(UpdateAge) do on_success { render_serialized(result.user, BasicUserSerializer, root: "user") } end end ``` - Rspec matchers and steps inspector, improving the dev experience while creating specs for a service ```ruby RSpec.describe(UpdateAge) do subject(:result) do described_class.call(guardian: guardian, user_id: user.id, age: age) end fab!(:user) { Fabricate(:user) } fab!(:current_user) { Fabricate(:admin) } let(:guardian) { Guardian.new(current_user) } let(:age) { 1 } it { expect(user.reload.age).to eq(age) } end ``` Note in case of unexpected failure in your spec, the output will give all the relevant information: ``` 1) UpdateAge when no channel_id is given is expected to fail to find a model named 'user' Failure/Error: it { is_expected.to fail_to_find_a_model(:user) } Expected model 'foo' (key: 'result.model.user') was not found in the result object. [1/4] [model] 'user' ❌ [2/4] [policy] 'can_see_user' [3/4] [contract] 'default' [4/4] [step] 'update_age' /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/update_age.rb:32:in `fetch_user': missing keyword: :user_id (ArgumentError) from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/base.rb:202:in `instance_exec' from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/base.rb:202:in `call' from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/base.rb:219:in `call' from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/base.rb:417:in `block in run!' from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/base.rb:417:in `each' from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/base.rb:417:in `run!' from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/base.rb:411:in `run' from <internal:kernel>:90:in `tap' from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/app/services/base.rb:302:in `call' from /Users/joffreyjaffeux/Code/pr-discourse/plugins/chat/spec/services/update_age_spec.rb:15:in `block (3 levels) in <main>' ```		2023-02-13 13:09:57 +01:00
..
with_service_helper.rb