TechDocs: Use discovery instead of config to read base url

plugins/techdocs-backend/package.json

@@ -23,6 +23,7 @@
     "@backstage/backend-common": "^0.2.0",
     "@backstage/catalog-model": "^0.2.0",
     "@backstage/config": "^0.1.1",
+    "@backstage/core-api": "^0.2.1",
     "@types/dockerode": "^2.5.34",
     "@types/express": "^4.17.6",
     "command-exists-promise": "^2.0.2",

plugins/techdocs-backend/src/service/standaloneServer.ts

@@ -53,7 +53,7 @@ export async function startStandaloneServer(
   const techdocsGenerator = new TechdocsGenerator(logger, config);
   generators.register('techdocs', techdocsGenerator);
 
-  const publisher = new LocalPublish(logger, config);
+  const publisher = new LocalPublish(logger, discovery);
 
   const dockerClient = new Docker();
 

plugins/techdocs-backend/src/techdocs/stages/publish/local.test.ts

@@ -17,7 +17,7 @@
 /* eslint-disable no-restricted-syntax */
 import fs from 'fs-extra';
 import path from 'path';
-import { getVoidLogger } from '@backstage/backend-common';
+import { getVoidLogger, SingleHostDiscovery } from '@backstage/backend-common';
 import { ConfigReader } from '@backstage/config';
 import { LocalPublish } from './local';
 
@@ -38,8 +38,21 @@ const logger = getVoidLogger();
 
 describe('local publisher', () => {
   it('should publish generated documentation dir', async () => {
-    const testConfig = ConfigReader.fromConfigs([{ context: '', data: {} }]);
-    const publisher = new LocalPublish(logger, testConfig);
+    const testConfig = ConfigReader.fromConfigs([
+      {
+        context: '',
+        data: {
+          backend: {
+            baseUrl: 'http://localhost:7000',
+            listen: {
+              port: 7000,
+            },
+          },
+        },
+      },
+    ]);
+    const testDiscovery = SingleHostDiscovery.fromConfig(testConfig);
+    const publisher = new LocalPublish(logger, testDiscovery);
 
     const mockEntity = createMockEntity();
 

plugins/techdocs-backend/src/techdocs/stages/publish/local.ts

@@ -18,15 +18,15 @@ import { Logger } from 'winston';
 import { Entity } from '@backstage/catalog-model';
 import { PublisherBase } from './types';
 import { resolvePackagePath } from '@backstage/backend-common';
-import { Config } from '@backstage/config';
+import { DiscoveryApi } from '@backstage/core-api';
 
 export class LocalPublish implements PublisherBase {
   private readonly logger: Logger;
-  private readonly config: Config;
+  private readonly discoveryApi: DiscoveryApi;
 
-  constructor(logger: Logger, config: Config) {
+  constructor(logger: Logger, discoveryApi: DiscoveryApi) {
     this.logger = logger;
-    this.config = config;
+    this.discoveryApi = discoveryApi;
   }
 
   publish({
@@ -66,9 +66,10 @@ export class LocalPublish implements PublisherBase {
           reject(err);
         }
 
-        const backendBaseUrl = this.config.getString('backend.baseUrl');
-        resolve({
-          remoteUrl: `${backendBaseUrl}/api/techdocs/static/docs/${entity.metadata.name}`,
+        this.discoveryApi.getBaseUrl('techdocs').then(techdocsApiUrl => {
+          resolve({
+            remoteUrl: `${techdocsApiUrl}/static/docs/${entity.metadata.name}`,
+          });
         });
       });
     });