Allow to pass custom transformer parameters via the request url

Reviewed By: davidaurelio

Differential Revision: D6869137

fbshipit-source-id: a985b2df7e4fca308e62adaededc2ad0038d5373

packages/metro/src/DeltaBundler/DeltaCalculator.js

@@ -160,6 +160,7 @@ class DeltaCalculator extends EventEmitter {
 
     const transformOptionsForBlacklist = {
       assetDataPlugins: this._options.assetPlugins,
+      customTransformOptions: this._options.customTransformOptions,
       enableBabelRCLookup,
       dev: this._options.dev,
       hot: this._options.hot,

packages/metro/src/HmrServer/getBundlingOptionsForHmr.js

@@ -13,6 +13,7 @@
 'use strict';
 
 import type {Options as BundleOptions} from '../DeltaBundler';
+import type {CustomTransformOptions} from '../JSTransformer/worker';
 
 /**
  * Module to easily create the needed configuration parameters needed for the
@@ -21,6 +22,7 @@ import type {Options as BundleOptions} from '../DeltaBundler';
 module.exports = function getBundlingOptionsForHmr(
   entryFile: string,
   platform: string,
+  customTransformOptions: CustomTransformOptions,
 ): BundleOptions {
   // These are the really meaningful bundling options. The others below are
   // not relevant for HMR.
@@ -36,6 +38,7 @@ module.exports = function getBundlingOptionsForHmr(
     ...mainOptions,
     assetPlugins: [],
     bundleType: 'hmr',
+    customTransformOptions,
     dev: true,
     entryModuleOnly: false,
     excludeSource: false,

packages/metro/src/HmrServer/index.js

@@ -15,6 +15,8 @@
 const addParamsToDefineCall = require('../lib/addParamsToDefineCall');
 const formatBundlingError = require('../lib/formatBundlingError');
 const getBundlingOptionsForHmr = require('./getBundlingOptionsForHmr');
+const nullthrows = require('fbjs/lib/nullthrows');
+const parseCustomTransformOptions = require('../lib/parseCustomTransformOptions');
 const querystring = require('querystring');
 const url = require('url');
 
@@ -53,10 +55,10 @@ class HmrServer<TClient: Client> {
     clientUrl: string,
     sendFn: (data: string) => mixed,
   ): Promise<Client> {
-    const {bundleEntry, platform} = querystring.parse(
-      /* $FlowFixMe: url might be null */
-      url.parse(clientUrl).query,
-    );
+    const urlObj = nullthrows(url.parse(clientUrl, true));
+
+    const {bundleEntry, platform} = nullthrows(urlObj.query);
+    const customTransformOptions = parseCustomTransformOptions(urlObj);
 
     // Create a new DeltaTransformer for each client. Once the clients are
     // modified to support Delta Bundles, they'll be able to pass the
@@ -64,7 +66,7 @@ class HmrServer<TClient: Client> {
     // the same DeltaTransformer between the WS connection and the HTTP one.
     const deltaBundler = this._packagerServer.getDeltaBundler();
     const {deltaTransformer} = await deltaBundler.getDeltaTransformer(
-      getBundlingOptionsForHmr(bundleEntry, platform),
+      getBundlingOptionsForHmr(bundleEntry, platform, customTransformOptions),
     );
 
     // Trigger an initial build to start up the DeltaTransformer.

packages/metro/src/JSTransformer/worker/index.js

@@ -62,8 +62,11 @@ export type Transformer<ExtraOptions: {} = {}> = {
   getCacheKey: () => string,
 };
 
+export type CustomTransformOptions = {[string]: mixed, __proto__: null};
+
 export type TransformOptionsStrict = {|
   +assetDataPlugins: $ReadOnlyArray<string>,
+  +customTransformOptions?: CustomTransformOptions,
   +enableBabelRCLookup: boolean,
   +dev: boolean,
   +hot: boolean,
@@ -75,6 +78,7 @@ export type TransformOptionsStrict = {|
 
 export type TransformOptions = {
   +assetDataPlugins: $ReadOnlyArray<string>,
+  +customTransformOptions?: CustomTransformOptions,
   +enableBabelRCLookup?: boolean,
   +dev?: boolean,
   +hot?: boolean,

packages/metro/src/Server/__tests__/Server-test.js

@@ -183,6 +183,7 @@ describe('processRequest', () => {
           {
             assetPlugins: [],
             bundleType: 'bundle',
+            customTransformOptions: {},
             deltaBundleId: expect.any(String),
             dev: true,
             entryFile: 'index.ios.js',
@@ -214,6 +215,7 @@ describe('processRequest', () => {
           {
             assetPlugins: [],
             bundleType: 'bundle',
+            customTransformOptions: {},
             deltaBundleId: expect.any(String),
             dev: true,
             entryFile: 'index.js',
@@ -245,6 +247,7 @@ describe('processRequest', () => {
       expect(Serializers.fullBundle).toBeCalledWith(expect.any(DeltaBundler), {
         assetPlugins: ['assetPlugin1', 'assetPlugin2'],
         bundleType: 'bundle',
+        customTransformOptions: {},
         deltaBundleId: expect.any(String),
         dev: true,
         entryFile: 'index.js',
@@ -447,6 +450,7 @@ describe('processRequest', () => {
             expect.any(DeltaBundler),
             {
               assetPlugins: [],
+              customTransformOptions: {},
               deltaBundleId: null,
               dev: true,
               entryFile: 'foo file',

packages/metro/src/Server/index.js

@@ -22,6 +22,8 @@ const formatBundlingError = require('../lib/formatBundlingError');
 const getMaxWorkers = require('../lib/getMaxWorkers');
 const getOrderedDependencyPaths = require('../lib/getOrderedDependencyPaths');
 const mime = require('mime-types');
+const nullthrows = require('fbjs/lib/nullthrows');
+const parseCustomTransformOptions = require('../lib/parseCustomTransformOptions');
 const parsePlatformFilePath = require('../node-haste/lib/parsePlatformFilePath');
 const path = require('path');
 const symbolicate = require('./symbolicate');
@@ -762,10 +764,10 @@ class Server {
 
   _getOptionsFromUrl(reqUrl: string): BundleOptions & DeltaBundlerOptions {
     // `true` to parse the query param as an object.
-    const urlObj = url.parse(reqUrl, true);
+    const urlObj = nullthrows(url.parse(reqUrl, true));
+    const urlQuery = nullthrows(urlObj.query);
 
-    /* $FlowFixMe: `pathname` could be empty for an invalid URL */
-    const pathname = decodeURIComponent(urlObj.pathname);
+    const pathname = urlObj.pathname ? decodeURIComponent(urlObj.pathname) : '';
 
     let isMap = false;
 
@@ -795,38 +797,38 @@ class Server {
 
     // try to get the platform from the url
     const platform =
-      /* $FlowFixMe: `query` could be empty for an invalid URL */
-      urlObj.query.platform ||
+      urlQuery.platform ||
       parsePlatformFilePath(pathname, this._platforms).platform;
 
-    /* $FlowFixMe: `query` could be empty for an invalid URL */
-    const deltaBundleId = urlObj.query.deltaBundleId;
+    const deltaBundleId = urlQuery.deltaBundleId;
 
-    /* $FlowFixMe: `query` could be empty for an invalid URL */
-    const assetPlugin = urlObj.query.assetPlugin;
+    const assetPlugin = urlQuery.assetPlugin;
     const assetPlugins = Array.isArray(assetPlugin)
       ? assetPlugin
       : typeof assetPlugin === 'string' ? [assetPlugin] : [];
 
-    const dev = this._getBoolOptionFromQuery(urlObj.query, 'dev', true);
-    const minify = this._getBoolOptionFromQuery(urlObj.query, 'minify', false);
+    const dev = this._getBoolOptionFromQuery(urlQuery, 'dev', true);
+    const minify = this._getBoolOptionFromQuery(urlQuery, 'minify', false);
     const excludeSource = this._getBoolOptionFromQuery(
-      urlObj.query,
+      urlQuery,
       'excludeSource',
       false,
     );
     const includeSource = this._getBoolOptionFromQuery(
-      urlObj.query,
+      urlQuery,
       'inlineSourceMap',
       false,
     );
 
+    const customTransformOptions = parseCustomTransformOptions(urlObj);
+
     return {
       sourceMapUrl: url.format({
         ...urlObj,
         pathname: pathname.replace(/\.(bundle|delta)$/, '.map'),
       }),
       bundleType: isMap ? 'map' : deltaBundleId ? 'delta' : 'bundle',
+      customTransformOptions,
       entryFile,
       deltaBundleId,
       dev,
@@ -873,6 +875,7 @@ class Server {
 
   static DEFAULT_BUNDLE_OPTIONS = {
     assetPlugins: [],
+    customTransformOptions: Object.create(null),
     dev: true,
     entryModuleOnly: false,
     excludeSource: false,

packages/metro/src/lib/GlobalTransformCache.js

@@ -24,6 +24,7 @@ const path = require('path');
 const throat = require('throat');
 
 import type {
+  CustomTransformOptions,
   Options as TransformWorkerOptions,
   TransformOptionsStrict,
 } from '../JSTransformer/worker';
@@ -440,6 +441,7 @@ class OptionsHasher {
   ): crypto$Hash {
     const {
       assetDataPlugins,
+      customTransformOptions,
       enableBabelRCLookup,
       dev,
       hot,
@@ -472,6 +474,9 @@ class OptionsHasher {
     hash.update(JSON.stringify(assetDataPlugins));
     hash.update(JSON.stringify(platform));
     hash.update(JSON.stringify(this.toLocalPath(projectRoot)));
+    hash.update(
+      JSON.stringify(this.sortTransformOptions(customTransformOptions || {})),
+    );
 
     return hash;
   }
@@ -483,6 +488,14 @@ class OptionsHasher {
   toLocalPath(filePath: string): string {
     return path.relative(this._rootPath, filePath);
   }
+
+  sortTransformOptions(
+    options: CustomTransformOptions,
+  ): Array<[string, mixed]> {
+    return Object.keys(options)
+      .sort()
+      .map(key => [key, options[key]]);
+  }
 }
 
 class CannotHashOptionsError extends Error {

packages/metro/src/lib/__tests__/__snapshots__/GlobalTransformCache-test.js.snap

@@ -19,12 +19,12 @@ Object {
 exports[`GlobalTransformCache fetches results 1`] = `
 Array [
   Object {
-    "code": "/* code from http://globalcache.com/a00af5f7803566564fc1e5bd209552899c7354e1-foo.js */",
+    "code": "/* code from http://globalcache.com/3b3b861b6b80dd038c51262ca8b8b9f76e353ada-foo.js */",
     "dependencies": Array [],
     "dependencyOffsets": Array [],
   },
   Object {
-    "code": "/* code from http://globalcache.com/50013dd319b49a40f1b3d325be62320a4c2a6c82-bar.js */",
+    "code": "/* code from http://globalcache.com/087b5bc3467f9a0670e49ce9118e6f6791aa12c6-bar.js */",
     "dependencies": Array [],
     "dependencyOffsets": Array [],
   },

packages/metro/src/lib/__tests__/parseCustomTransformOptions-test.js

@@ -0,0 +1,42 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @emails oncall+javascript_foundation
+ * @format
+ * @flow
+ */
+
+'use strict';
+
+const parseCustomTransformOptions = require('../parseCustomTransformOptions');
+const url = require('url');
+
+it('should parse some custom options from a http url', () => {
+  const myUrl =
+    'http://localhost/my/bundle.bundle?dev=true&transform.foo=value&transform.bar=other';
+
+  expect(parseCustomTransformOptions(url.parse(myUrl, true))).toEqual({
+    foo: 'value',
+    bar: 'other',
+  });
+});
+
+it('should parse some custom options from a websocket url', () => {
+  const myUrl = 'ws://localhost/hot?transform.foo=value&transform.bar=other';
+
+  expect(parseCustomTransformOptions(url.parse(myUrl, true))).toEqual({
+    foo: 'value',
+    bar: 'other',
+  });
+});
+
+it('should return an empty object if there are no custom params', () => {
+  const myUrl = 'http://localhost/my/bundle.bundle?dev=true';
+
+  expect(parseCustomTransformOptions(url.parse(myUrl, true))).toEqual({});
+});

packages/metro/src/lib/parseCustomTransformOptions.js

@@ -0,0 +1,35 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @emails oncall+javascript_foundation
+ * @format
+ * @flow
+ */
+
+'use strict';
+
+const nullthrows = require('fbjs/lib/nullthrows');
+
+import type {CustomTransformOptions} from '../JSTransformer/worker';
+
+const PREFIX = 'transform.';
+
+module.exports = function parseCustomTransformOptions(urlObj: {
+  query?: {[string]: string},
+}): CustomTransformOptions {
+  const customTransformOptions = Object.create(null);
+  const query = nullthrows(urlObj.query);
+
+  Object.keys(query).forEach(key => {
+    if (key.startsWith(PREFIX)) {
+      customTransformOptions[key.substr(PREFIX.length)] = query[key];
+    }
+  });
+
+  return customTransformOptions;
+};

packages/metro/src/shared/types.flow.js

@@ -17,6 +17,7 @@ import type {
   PostProcessBundleSourcemap,
 } from '../Bundler';
 import type {PostProcessModules} from '../DeltaBundler';
+import type {CustomTransformOptions} from '../JSTransformer/worker';
 import type {DynamicRequiresBehavior} from '../ModuleGraph/worker/collectDependencies';
 import type {GlobalTransformCache} from '../lib/GlobalTransformCache';
 import type {TransformCache} from '../lib/TransformCaching';
@@ -34,6 +35,7 @@ type MetroSourceMapOrMappings =
 export type BundleOptions = {
   +assetPlugins: Array<string>,
   bundleType: BundleType,
+  customTransformOptions: CustomTransformOptions,
   dev: boolean,
   entryFile: string,
   +entryModuleOnly: boolean,