feat(events,example): integrate at example backend

Integrate plugins-events-backend with plugins-events-backend-module-http
at the example backend.

Relates-to: #11082
Signed-off-by: Patrick Jungermann <Patrick.Jungermann@gmail.com>

packages/backend/package.json

@@ -40,6 +40,8 @@
     "@backstage/plugin-badges-backend": "workspace:^",
     "@backstage/plugin-catalog-backend": "workspace:^",
     "@backstage/plugin-code-coverage-backend": "workspace:^",
+    "@backstage/plugin-events-backend": "workspace:^",
+    "@backstage/plugin-events-node": "workspace:^",
     "@backstage/plugin-graphql-backend": "workspace:^",
     "@backstage/plugin-jenkins-backend": "workspace:^",
     "@backstage/plugin-kafka-backend": "workspace:^",

packages/backend/src/index.ts

@@ -43,6 +43,7 @@ import auth from './plugins/auth';
 import azureDevOps from './plugins/azure-devops';
 import catalog from './plugins/catalog';
 import codeCoverage from './plugins/codecoverage';
+import events from './plugins/events';
 import kubernetes from './plugins/kubernetes';
 import kafka from './plugins/kafka';
 import rollbar from './plugins/rollbar';
@@ -141,10 +142,12 @@ async function main() {
   );
   const permissionEnv = useHotMemoize(module, () => createEnv('permission'));
   const playlistEnv = useHotMemoize(module, () => createEnv('playlist'));
+  const eventsEnv = useHotMemoize(module, () => createEnv('events'));
 
   const apiRouter = Router();
   apiRouter.use('/catalog', await catalog(catalogEnv));
   apiRouter.use('/code-coverage', await codeCoverage(codeCoverageEnv));
+  apiRouter.use('/events', await events(eventsEnv, []));
   apiRouter.use('/rollbar', await rollbar(rollbarEnv));
   apiRouter.use('/scaffolder', await scaffolder(scaffolderEnv));
   apiRouter.use('/tech-insights', await techInsights(techInsightsEnv));

packages/backend/src/plugins/events.ts

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2022 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {
+  EventsBackend,
+  HttpPostIngressEventPublisher,
+} from '@backstage/plugin-events-backend';
+import { EventSubscriber } from '@backstage/plugin-events-node';
+import { Router } from 'express';
+import { PluginEnvironment } from '../types';
+
+export default async function createPlugin(
+  env: PluginEnvironment,
+  subscribers: EventSubscriber[],
+): Promise<Router> {
+  const eventsRouter = Router();
+  const httpRouter = Router();
+  eventsRouter.use('/http', httpRouter);
+
+  const http = HttpPostIngressEventPublisher.fromConfig({
+    config: env.config,
+    logger: env.logger,
+    router: httpRouter,
+  });
+
+  await new EventsBackend(env.logger)
+    .addPublishers(http)
+    .addSubscribers(subscribers)
+    .start();
+
+  return eventsRouter;
+}

yarn.lock

@@ -5541,7 +5541,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@backstage/plugin-events-backend@workspace:plugins/events-backend":
+"@backstage/plugin-events-backend@workspace:^, @backstage/plugin-events-backend@workspace:plugins/events-backend":
   version: 0.0.0-use.local
   resolution: "@backstage/plugin-events-backend@workspace:plugins/events-backend"
   dependencies:
@@ -22341,6 +22341,8 @@ __metadata:
     "@backstage/plugin-badges-backend": "workspace:^"
     "@backstage/plugin-catalog-backend": "workspace:^"
     "@backstage/plugin-code-coverage-backend": "workspace:^"
+    "@backstage/plugin-events-backend": "workspace:^"
+    "@backstage/plugin-events-node": "workspace:^"
     "@backstage/plugin-graphql-backend": "workspace:^"
     "@backstage/plugin-jenkins-backend": "workspace:^"
     "@backstage/plugin-kafka-backend": "workspace:^"