feat: make lighthouse url configurable

plugins/lighthouse/README.md

@@ -36,16 +36,24 @@ your [`apis.ts`](https://github.com/spotify/backstage/blob/master/packages/app/s
 
 ```js
 import { ApiHolder, ApiRegistry } from '@backstage/core';
+import { Config } from '@backstage/config';
 import {
   lighthouseApiRef,
   LighthouseRestApi,
 } from '@backstage/plugin-lighthouse';
 
-const builder = ApiRegistry.builder();
+export const apis = (config: ConfigApi) => {
+  const builder = ApiRegistry.builder();
 
-export const lighthouseApi =
-  new LighthouseRestApi(/* your service url here! */);
-builder.add(lighthouseApiRef, lighthouseApi);
+  builder.add(lighthouseApiRef, LighthouseRestApi.fromConfig(config));
 
-export default builder.build() as ApiHolder;
+  return builder.build() as ApiHolder;
+}
+```
+
+Then configure the lighthouse service url in your [`app-config.yaml`](https://github.com/spotify/backstage/blob/master/app-config.yaml).
+
+```yaml
+lighthouse:
+  baseUrl: http://your-service-url
 ```

plugins/lighthouse/package.json

@@ -21,6 +21,7 @@
     "start": "backstage-cli plugin:serve"
   },
   "dependencies": {
+    "@backstage/config": "^0.1.1-alpha.20",
     "@backstage/core": "^0.1.1-alpha.20",
     "@backstage/theme": "^0.1.1-alpha.20",
     "@material-ui/core": "^4.9.1",

plugins/lighthouse/src/api.ts

@@ -15,6 +15,7 @@
  */
 
 import { createApiRef } from '@backstage/core';
+import { Config } from '@backstage/config';
 
 export type LighthouseCategoryId =
   | 'pwa'
@@ -111,6 +112,10 @@ export const lighthouseApiRef = createApiRef<LighthouseApi>({
 });
 
 export class LighthouseRestApi implements LighthouseApi {
+  static fromConfig(config: Config) {
+    return new LighthouseRestApi(config.getString('lighthouse.baseUrl'));
+  }
+
   constructor(public url: string) {}
 
   private async fetch<T = any>(input: string, init?: RequestInit): Promise<T> {