move plugin management from ui-core to server-core

Summary:
Follow up of D32665064, this diff moves all plugin management logic from flipper-ui to flipper-server. Things like downloading, installing, querying new plugins.

Loading plugins is handled separately in the next diff.

Reviewed By: nikoant

Differential Revision: D32666537

fbshipit-source-id: 9786b82987f00180bb26200e38735b334dc4d5c3

desktop/flipper-server-core/src/utils/pathUtils.tsx

@@ -0,0 +1,40 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+// We use sync access once per startup.
+/* eslint-disable node/no-sync */
+
+import path from 'path';
+import fs from 'fs';
+import {getFlipperServerConfig} from '../FlipperServerConfig';
+import {isFBBuild} from '../fb-stubs/constants';
+
+export function getStaticPath(
+  relativePath: string = '.',
+  {asarUnpacked}: {asarUnpacked: boolean} = {asarUnpacked: false},
+) {
+  const staticDir = getFlipperServerConfig().paths.staticPath;
+  const absolutePath = path.resolve(staticDir, relativePath);
+  // Unfortunately, path.resolve, fs.pathExists, fs.read etc do not automatically work with asarUnpacked files.
+  // All these functions still look for files in "app.asar" even if they are unpacked.
+  // Looks like automatic resolving for asarUnpacked files only work for "child_process" module.
+  // So we're using a hack here to actually look to "app.asar.unpacked" dir instead of app.asar package.
+  return asarUnpacked
+    ? absolutePath.replace('app.asar', 'app.asar.unpacked')
+    : absolutePath;
+}
+
+export function getChangelogPath() {
+  const changelogPath = getStaticPath(isFBBuild ? 'facebook' : '.');
+  if (fs.existsSync(changelogPath)) {
+    return changelogPath;
+  } else {
+    throw new Error('Changelog path path does not exist: ' + changelogPath);
+  }
+}