Merge plugin package.json from public and fb-internal parts

Summary: Allow splitting package.json to public one and fb-internal one located in "fb/package.json". When plugin is packaged, fields in package.json are overwritten by fields from "fb/package.json" if they exist. This give us a way to specify additional metadata which only make sense internally (e.g. oncall and internal links to docs and support).

Reviewed By: mweststrate

Differential Revision: D28542101

fbshipit-source-id: c0167461897a994e5731aaf0fe625de052eda864

desktop/plugin-lib/src/getPluginDetails.ts

@@ -16,6 +16,16 @@ import {
 } from './PluginDetails';
 import {pluginCacheDir} from './pluginPaths';
 
+export async function readPluginPackageJson(dir: string): Promise<any> {
+  const baseJson = await fs.readJson(path.join(dir, 'package.json'));
+  if (await fs.pathExists(path.join(dir, 'fb', 'package.json'))) {
+    const addedJson = await fs.readJson(path.join(dir, 'fb', 'package.json'));
+    return Object.assign({}, baseJson, addedJson);
+  } else {
+    return baseJson;
+  }
+}
+
 export function isPluginJson(packageJson: any): boolean {
   return packageJson?.keywords?.includes('flipper-plugin');
 }
@@ -51,8 +61,7 @@ export async function getInstalledPluginDetails(
   dir: string,
   packageJson?: any,
 ): Promise<InstalledPluginDetails> {
-  packageJson =
-    packageJson ?? (await fs.readJson(path.join(dir, 'package.json')));
+  packageJson = packageJson ?? (await readPluginPackageJson(dir));
   const pluginDetails = getPluginDetails(packageJson);
   const entry =
     pluginDetails.specVersion === 1