feat(gitlab): support new backend system (#62)

Add support to install the gitlab user processor via a catalog module

plugins/gitlab-catalog-backend/README.md

@@ -31,21 +31,12 @@ Enriches existing `User` entities with information from Gitlab, notably the user
 
 #### Installation
 
-Add the following to your `packages/backend/catalog.ts`:
+Add the following to your `packages/backend/index.ts`:
 
 ```ts
-import { GitlabUserProcessor } from '@seatgeek/backstage-plugin-gitlab-catalog-backend';
-
-export default async function createPlugin(
-  env: PluginEnvironment,
-): Promise<Router> {
-  const builder = CatalogBuilder.create(env);
-  builder.addProcessor(
-    // Add the gitlab user processor
-    GitlabUserProcessor.fromConfig(env.config, env.logger),
-  );
-  const { processingEngine, router } = await builder.build();
-  processingEngine.start();
-  return router;
-}
+// in your imports
+import { catalogModuleGitlabUserProcessor } from '@seatgeek/backstage-plugin-gitlab-catalog-backend';
+
+// in your catalog modules
+backend.add(catalogModuleGitlabUserProcessor);
 ```

plugins/gitlab-catalog-backend/package.json

@@ -27,9 +27,11 @@
   },
   "dependencies": {
     "@backstage/backend-common": "^0.24.0",
+    "@backstage/backend-plugin-api": "^0.8.0",
     "@backstage/catalog-model": "^1.6.0",
     "@backstage/config": "^1.2.0",
     "@backstage/plugin-catalog-common": "^1.0.26",
+    "@backstage/plugin-catalog-node": "^1.12.5",
     "@gitbeaker/rest": "^40.0.1",
     "@types/express": "*",
     "express": "^4.17.1",

plugins/gitlab-catalog-backend/src/GitlabUserProcessor.ts

@@ -2,6 +2,7 @@
  * Copyright SeatGeek
  * Licensed under the terms of the Apache-2.0 license. See LICENSE file in project root for terms.
  */
+import { LoggerService } from '@backstage/backend-plugin-api';
 import { Entity, isUserEntity } from '@backstage/catalog-model';
 import { Config } from '@backstage/config';
 import { LocationSpec } from '@backstage/plugin-catalog-common';
@@ -10,7 +11,6 @@ import type {
   CatalogProcessorEmit,
 } from '@backstage/plugin-catalog-node';
 import { ExpandedUserSchema, Gitlab } from '@gitbeaker/rest';
-import { Logger } from 'winston';
 
 const GITLAB_PER_PAGE_LIMIT = 500;
 const GITLAB_DEFAULT_HOST = 'https://gitlab.com';
@@ -23,7 +23,7 @@ const GITLAB_DEFAULT_HOST = 'https://gitlab.com';
  */
 export class GitlabUserProcessor implements CatalogProcessor {
   private readonly gitlab: InstanceType<typeof Gitlab>;
-  private readonly logger: Logger;
+  private readonly logger: LoggerService;
   private cacheLoaded: boolean;
   private userLookup: Map<string, ExpandedUserSchema>;
   // guarantee that users are loaded only once
@@ -77,7 +77,10 @@ export class GitlabUserProcessor implements CatalogProcessor {
     return this.userLookup;
   }
 
-  static fromConfig(config: Config, logger: Logger): GitlabUserProcessor[] {
+  static fromConfig(
+    config: Config,
+    logger: LoggerService,
+  ): GitlabUserProcessor[] {
     const token = config.getOptionalString('gitlabCatalog.token');
     if (!token) {
       logger.warn(
@@ -103,7 +106,7 @@ export class GitlabUserProcessor implements CatalogProcessor {
     ];
   }
 
-  constructor(gitlab: InstanceType<typeof Gitlab>, logger: Logger) {
+  constructor(gitlab: InstanceType<typeof Gitlab>, logger: LoggerService) {
     this.gitlab = gitlab;
     this.logger = logger;
     this.userLookup = new Map();

plugins/gitlab-catalog-backend/src/catalogModuleGitlabUserProcessor.ts

@@ -0,0 +1,31 @@
+/*
+ * Copyright SeatGeek
+ * Licensed under the terms of the Apache-2.0 license. See LICENSE file in project root for terms.
+ */
+import {
+  coreServices,
+  createBackendModule,
+} from '@backstage/backend-plugin-api';
+import { catalogProcessingExtensionPoint } from '@backstage/plugin-catalog-node/alpha';
+import { GitlabUserProcessor } from './GitlabUserProcessor';
+
+export const catalogModuleGitlabUserProcessor = createBackendModule({
+  pluginId: 'catalog',
+  moduleId: 'gitlab-user-processor',
+  register(env) {
+    env.registerInit({
+      deps: {
+        catalog: catalogProcessingExtensionPoint,
+        config: coreServices.rootConfig,
+        logger: coreServices.logger,
+      },
+      async init({ catalog, config, logger }) {
+        const gitlabUserProcessor = GitlabUserProcessor.fromConfig(
+          config,
+          logger,
+        );
+        catalog.addProcessor(gitlabUserProcessor);
+      },
+    });
+  },
+});

plugins/gitlab-catalog-backend/src/index.ts

@@ -3,3 +3,4 @@
  * Licensed under the terms of the Apache-2.0 license. See LICENSE file in project root for terms.
  */
 export { GitlabUserProcessor } from './GitlabUserProcessor';
+export { catalogModuleGitlabUserProcessor } from './catalogModuleGitlabUserProcessor';