Move configuration to module

Summary:
Moves the JSON config access to one module instead of
ad-hoc de-serialising the object all over the place.
This also adds a type for it so we hopefully won't typo things that easily.

Reviewed By: danielbuechele

Differential Revision: D13956612

fbshipit-source-id: 48098deafedf18cc86c8802a3c40fba9394b8262

src/utils/processConfig.js

@@ -0,0 +1,40 @@
+/**
+ * Copyright 2018-present Facebook.
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ * @format
+ */
+
+import {remote} from 'electron';
+
+export type ProcessConfig = {|
+  disabledPlugins: Set<string>,
+  pluginPaths: Array<string>,
+  lastWindowPosition: ?{x: number, y: number, width: number, height: number},
+  screenCapturePath: ?string,
+  updaterEnabled: boolean,
+|};
+
+let configObj = null;
+export default function config(): ProcessConfig {
+  if (configObj === null) {
+    const json = JSON.parse(
+      // $FlowFixMe: process.env not in type defs
+      remote?.process.env.CONFIG || process.env.CONFIG || '{}',
+    );
+    configObj = {
+      disabledPlugins: new Set(json.disabledPlugins || []),
+      pluginPaths: json.pluginPaths || [],
+      lastWindowPosition: json.lastWindowPosition,
+      updaterEnabled:
+        typeof json.updaterEnabled === 'boolean' ? json.updaterEnabled : true,
+      screenCapturePath: json.screenCapturePath,
+    };
+  }
+
+  return configObj;
+}
+
+export function resetConfigForTesting() {
+  configObj = null;
+}