Forward Jira uninstall events to self-managed

When instance_url is set the JiraConnectInstallation
serves as proxy for a self-managed instance. In this
case it should forward the event.

app/controllers/jira_connect/events_controller.rb

@@ -19,7 +19,7 @@ class JiraConnect::EventsController < JiraConnect::ApplicationController
   end
 
   def uninstalled
-    if current_jira_installation.destroy
+    if JiraConnectInstallations::DestroyService.execute(current_jira_installation, jira_connect_base_path, jira_connect_events_uninstalled_path)
       head :ok
     else
       head :unprocessable_entity

app/services/jira_connect_installations/destroy_service.rb

+# frozen_string_literal: true
+
+module JiraConnectInstallations
+  class DestroyService
+    def self.execute(installation, jira_connect_base_path, jira_connect_uninstalled_event_path)
+      new(installation, jira_connect_base_path, jira_connect_uninstalled_event_path).execute
+    end
+
+    def initialize(installation, jira_connect_base_path, jira_connect_uninstalled_event_path)
+      @installation = installation
+      @jira_connect_base_path = jira_connect_base_path
+      @jira_connect_uninstalled_event_path = jira_connect_uninstalled_event_path
+    end
+
+    def execute
+      if @installation.instance_url.present?
+        JiraConnect::ForwardEventWorker.perform_async(@installation.id, @jira_connect_base_path, @jira_connect_uninstalled_event_path)
+        return true
+      end
+
+      @installation.destroy
+    end
+  end
+end

app/workers/all_queues.yml

@@ -1078,6 +1078,15 @@
   :weight: 2
   :idempotent: true
   :tags: []
+- :name: jira_connect:jira_connect_forward_event
+  :worker_name: JiraConnect::ForwardEventWorker
+  :feature_category: :integrations
+  :has_external_dependencies: true
+  :urgency: :low
+  :resource_boundary: :unknown
+  :weight: 1
+  :idempotent:
+  :tags: []
 - :name: jira_connect:jira_connect_sync_branch
   :worker_name: JiraConnect::SyncBranchWorker
   :feature_category: :integrations

app/workers/jira_connect/forward_event_worker.rb

+# frozen_string_literal: true
+
+module JiraConnect
+  class ForwardEventWorker # rubocop:disable Scalability/IdempotentWorker
+    include ApplicationWorker
+
+    queue_namespace :jira_connect
+    feature_category :integrations
+    worker_has_external_dependencies!
+
+    def perform(installation_id, base_path, event_path)
+      installation = JiraConnectInstallation.find_by_id(installation_id)
+
+      return if installation&.instance_url.nil?
+
+      proxy_url = installation.instance_url + event_path
+      qsh = Atlassian::Jwt.create_query_string_hash(proxy_url, 'POST', installation.instance_url + base_path)
+      jwt = Atlassian::Jwt.encode({ iss: installation.client_key, qsh: qsh }, installation.shared_secret)
+
+      Gitlab::HTTP.post(proxy_url, headers: { 'Authorization' => "JWT #{jwt}" })
+    ensure
+      installation.destroy if installation
+    end
+  end
+end

spec/controllers/jira_connect/events_controller_spec.rb

@@ -66,19 +66,19 @@ RSpec.describe JiraConnect::EventsController do
         request.headers['Authorization'] = "JWT #{auth_token}"
       end
 
-      subject { post :uninstalled }
+      subject(:post_uninstalled) { post :uninstalled }
 
       context 'when JWT is invalid' do
         let(:auth_token) { 'invalid_token' }
 
         it 'returns 403' do
-          subject
+          post_uninstalled
 
           expect(response).to have_gitlab_http_status(:forbidden)
         end
 
         it 'does not delete the installation' do
-          expect { subject }.not_to change { JiraConnectInstallation.count }
+          expect { post_uninstalled }.not_to change { JiraConnectInstallation.count }
         end
       end
 
@@ -87,8 +87,27 @@ RSpec.describe JiraConnect::EventsController do
           Atlassian::Jwt.encode({ iss: installation.client_key, qsh: qsh }, installation.shared_secret)
         end
 
-        it 'deletes the installation' do
-          expect { subject }.to change { JiraConnectInstallation.count }.by(-1)
+        let(:jira_base_path) { '/-/jira_connect' }
+        let(:jira_event_path) { '/-/jira_connect/events/uninstalled' }
+
+        it 'calls the DestroyService and returns ok in case of success' do
+          expect_next_instance_of(JiraConnectInstallations::DestroyService, installation, jira_base_path, jira_event_path) do |destroy_service|
+            expect(destroy_service).to receive(:execute).and_return(true)
+          end
+
+          post_uninstalled
+
+          expect(response).to have_gitlab_http_status(:ok)
+        end
+
+        it 'calls the DestroyService and returns unprocessable_entity in case of failure' do
+          expect_next_instance_of(JiraConnectInstallations::DestroyService, installation, jira_base_path, jira_event_path) do |destroy_service|
+            expect(destroy_service).to receive(:execute).and_return(false)
+          end
+
+          post_uninstalled
+
+          expect(response).to have_gitlab_http_status(:unprocessable_entity)
         end
       end
     end

spec/services/jira_connect_installations/destroy_service_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe JiraConnectInstallations::DestroyService do
+  describe '.execute' do
+    it 'creates an instance and calls execute' do
+      expect_next_instance_of(described_class, 'param1', 'param2', 'param3') do |destroy_service|
+        expect(destroy_service).to receive(:execute)
+      end
+
+      described_class.execute('param1', 'param2', 'param3')
+    end
+  end
+
+  describe '#execute' do
+    let!(:installation) { create(:jira_connect_installation) }
+    let(:jira_base_path) { '/-/jira_connect' }
+    let(:jira_event_path) { '/-/jira_connect/events/uninstalled' }
+
+    subject { described_class.new(installation, jira_base_path, jira_event_path).execute }
+
+    it { is_expected.to be_truthy }
+
+    it 'deletes the installation' do
+      expect { subject }.to change(JiraConnectInstallation, :count).by(-1)
+    end
+
+    context 'and the installation has an instance_url set' do
+      let!(:installation) { create(:jira_connect_installation, instance_url: 'http://example.com') }
+
+      it { is_expected.to be_truthy }
+
+      it 'schedules a ForwardEventWorker background job and keeps the installation' do
+        expect(JiraConnect::ForwardEventWorker).to receive(:perform_async).with(installation.id, jira_base_path, jira_event_path)
+
+        expect { subject }.not_to change(JiraConnectInstallation, :count)
+      end
+    end
+  end
+end

spec/workers/jira_connect/forward_event_worker_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe JiraConnect::ForwardEventWorker do
+  describe '#perform' do
+    let!(:jira_connect_installation) { create(:jira_connect_installation, instance_url: self_managed_url, client_key: client_key, shared_secret: shared_secret) }
+    let(:base_path) { '/-/jira_connect' }
+    let(:event_path) { '/-/jira_connect/events/uninstalled' }
+
+    let(:self_managed_url) { 'http://example.com' }
+    let(:base_url) { self_managed_url + base_path }
+    let(:event_url) { self_managed_url + event_path }
+
+    let(:client_key) { '123' }
+    let(:shared_secret) { '123' }
+
+    subject { described_class.new.perform(jira_connect_installation.id, base_path, event_path) }
+
+    it 'forwards the event including the auth header and deletes the installation' do
+      stub_request(:post, event_url)
+
+      expect(Atlassian::Jwt).to receive(:create_query_string_hash).with(event_url, 'POST', base_url).and_return('some_qsh')
+      expect(Atlassian::Jwt).to receive(:encode).with({ iss: client_key, qsh: 'some_qsh' }, shared_secret).and_return('auth_token')
+      expect { subject }.to change(JiraConnectInstallation, :count).by(-1)
+
+      expect(WebMock).to have_requested(:post, event_url).with(headers: { 'Authorization' => 'JWT auth_token' })
+    end
+
+    context 'when installation does not exist' do
+      let(:jira_connect_installation) { instance_double(JiraConnectInstallation, id: -1) }
+
+      it 'does nothing' do
+        expect { subject }.not_to change(JiraConnectInstallation, :count)
+      end
+    end
+
+    context 'when installation does not have an instance_url' do
+      let!(:jira_connect_installation) { create(:jira_connect_installation) }
+
+      it 'forwards the event including the auth header' do
+        expect { subject }.to change(JiraConnectInstallation, :count).by(-1)
+
+        expect(WebMock).not_to have_requested(:post, '*')
+      end
+    end
+
+    context 'when it fails to forward the event' do
+      it 'still deletes the installation' do
+        allow(Gitlab::HTTP).to receive(:post).and_raise(StandardError)
+
+        expect { subject }.to raise_error(StandardError).and change(JiraConnectInstallation, :count).by(-1)
+      end
+    end
+  end
+end