Migrate webchannel-wrapper to gulp + google-closure-compiler

packages/webchannel-wrapper/externs/module.js

@@ -0,0 +1,19 @@
+/**
+ * @license
+ * Copyright 2020 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/** @type {!Object} */
+const module = {};

packages/webchannel-wrapper/externs/overrides.js

@@ -1,6 +1,6 @@
 /**
  * @license
- * Copyright 2017 Google Inc.
+ * Copyright 2017 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,7 +30,7 @@ goog.net.WebChannel.Options.messageHeaders;
 /** @type {Object<string, string>|undefined} */
 goog.net.WebChannel.Options.initMessageHeaders;
 
-/** @type {stringboolean|undefined} */
+/** @type {string|boolean|undefined} */
 goog.net.WebChannel.Options.messageContentType;
 
 /** @type {Object<string, string>|undefined|undefined} */

packages/webchannel-wrapper/gulpfile.js

@@ -0,0 +1,185 @@
+/**
+ * @license
+ * Copyright 2020 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+const gulp = require('gulp');
+const rollup = require('rollup');
+const closureCompiler = require('google-closure-compiler').gulp();
+const del = require('del');
+const path = require('path');
+const sourcemaps = require('gulp-sourcemaps');
+const { resolve } = require('path');
+const commonjs = require('rollup-plugin-commonjs');
+const rollupSourcemaps = require('rollup-plugin-sourcemaps');
+const typescriptPlugin = require('rollup-plugin-typescript2');
+const typescript = require('typescript');
+
+// The optimization level for the JS compiler.
+// Valid levels: WHITESPACE_ONLY, SIMPLE_OPTIMIZATIONS, ADVANCED_OPTIMIZATIONS.
+const OPTIMIZATION_LEVEL = 'ADVANCED_OPTIMIZATIONS';
+
+// For minified builds, wrap the output so we avoid leaking global variables.
+const CJS_WRAPPER_PREFIX = `(function() {`;
+const CJS_WRAPPER_SUFFIX =
+  `}).apply(typeof global !== 'undefined' ? ` +
+  `global : typeof self !== 'undefined' ? ` +
+  `self : typeof window !== 'undefined' ? window : {});`;
+
+const closureLibRoot = path.dirname(
+  require.resolve('google-closure-library/package.json')
+);
+
+const closureDefines = [
+  // Avoid unsafe eval() calls (https://github.com/firebase/firebase-js-sdk/issues/798)
+  'goog.json.USE_NATIVE_JSON=true',
+  // Disable debug logging (saves 8780 bytes).
+  'goog.DEBUG=false',
+  // Disable fallbacks for running async code (saves 1472 bytes).
+  'goog.ASSUME_NATIVE_PROMISE=true',
+  // Disables IE8-specific event fallback code (saves 523 bytes).
+  'goog.events.CAPTURE_SIMULATION_MODE=0',
+  // Disable IE-Specific ActiveX fallback for XHRs (saves 524 bytes).
+  'goog.net.XmlHttpDefines.ASSUME_NATIVE_XHR=true'
+];
+
+/**
+ * Generates a closure compiler build of webchannel-wrapper.
+ * @param {string} filename name of the generated file
+ * @param {string} prefix prefix to the compiled code
+ * @param {string} suffix suffix to the compiled code
+ */
+function createBuildTask(filename, prefix, suffix) {
+  return function closureBuild() {
+    return gulp
+      .src(
+        [
+          `${closureLibRoot}/closure/goog/**/*.js`,
+          `${closureLibRoot}/third_party/closure/goog/**/*.js`,
+          'src/**/*.js'
+        ],
+        { base: '.' }
+      )
+      .pipe(sourcemaps.init())
+      .pipe(
+        closureCompiler({
+          js_output_file: filename,
+          output_wrapper: `${prefix}%output%${suffix}`,
+          entry_point: 'firebase.webchannel.wrapper',
+          compilation_level: OPTIMIZATION_LEVEL,
+          externs: [
+            resolve(__dirname, './externs/overrides.js'),
+            resolve(__dirname, './externs/module.js')
+          ],
+          language_out: 'ECMASCRIPT_2017',
+          dependency_mode: 'PRUNE',
+          define: closureDefines
+        })
+      )
+      .pipe(sourcemaps.write('.'))
+      .pipe(gulp.dest('dist'));
+  };
+}
+
+function createRollupTask({
+  inputPath,
+  outputExtension,
+  compileToES5 = false,
+  format = 'es'
+}) {
+  return async function rollupBuild() {
+    const plugins = [rollupSourcemaps(), commonjs()];
+    if (compileToES5) {
+      plugins.push(
+        typescriptPlugin({
+          typescript,
+          // Uncomment for development only. Prevents caching between builds.
+          // clean: true,
+          compilerOptions: { allowJs: true },
+          include: ['dist/**/*.js']
+        })
+      );
+    }
+    const inputOptions = {
+      input: inputPath,
+      plugins
+    };
+
+    const outputOptions = {
+      file: `dist/index${outputExtension ? '.' : ''}${outputExtension}.js`,
+      format,
+      sourcemap: true,
+      // Prevents warning when compiling CJS that there are named and default exports together.
+      exports: 'named'
+    };
+
+    const bundle = await rollup.rollup(inputOptions);
+    return bundle.write(outputOptions);
+  };
+}
+
+async function deleteIntermediateFiles() {
+  await del('dist/temp');
+}
+
+// Closure-generated ES2017 intermediate file (CJS format)
+const intermediateCjsFile = 'temp/cjs.js';
+const intermediateCjsPath = resolve(__dirname, 'dist/', intermediateCjsFile);
+const cjsBuild = createBuildTask(
+  intermediateCjsFile,
+  CJS_WRAPPER_PREFIX,
+  CJS_WRAPPER_SUFFIX
+);
+
+// Closure-generated ES2017 intermediate file (no wrapper text)
+const intermediateEsmFile = 'temp/esm.js';
+const intermediateEsmPath = resolve(__dirname, 'dist/', intermediateEsmFile);
+const esmBuild = createBuildTask(intermediateEsmFile, '', '');
+
+// cjs output
+const rollupCjsTask = createRollupTask({
+  inputPath: intermediateCjsPath,
+  outputExtension: '',
+  compileToES5: true,
+  format: 'cjs'
+});
+gulp.task('cjs', gulp.series(cjsBuild, rollupCjsTask));
+
+// esm intermediateEsmPath
+const rollupEsmTask = createRollupTask({
+  inputPath: intermediateEsmPath,
+  outputExtension: 'esm',
+  compileToES5: true,
+  format: 'es'
+});
+gulp.task('esm', gulp.series(esmBuild, rollupEsmTask));
+
+// esm2017 output
+const rollup2017Task = createRollupTask({
+  inputPath: intermediateEsmPath,
+  outputExtension: 'esm2017',
+  compileToES5: false,
+  format: 'es'
+});
+gulp.task('esm2017', gulp.series(esmBuild, rollup2017Task));
+
+gulp.task(
+  'allEsm',
+  gulp.series(esmBuild, gulp.parallel(rollupEsmTask, rollup2017Task))
+);
+
+gulp.task('buildAll', gulp.parallel('cjs', 'allEsm'));
+
+gulp.task('default', gulp.series('buildAll', deleteIntermediateFiles));

packages/webchannel-wrapper/package.json

@@ -5,21 +5,26 @@
   "author": "Firebase <[email protected]> (https://firebase.google.com/)",
   "main": "dist/index.js",
   "module": "dist/index.esm.js",
+  "esm2017": "dist/index.esm2017.js",
   "files": [
     "dist"
   ],
   "scripts": {
     "dev": "watch 'yarn build' src",
-    "build": "node tools/build.js",
+    "build": "gulp",
     "prepare": "yarn build"
   },
   "license": "Apache-2.0",
   "devDependencies": {
-    "closure-builder": "2.3.8",
-    "google-closure-library": "20200224.0.0",
+    "google-closure-compiler": "20200406.0.0",
+    "google-closure-library": "20200406.0.0",
+    "gulp": "4.0.2",
+    "gulp-sourcemaps": "2.6.5",
     "rollup": "2.6.1",
     "rollup-plugin-commonjs": "10.1.0",
-    "rollup-plugin-sourcemaps": "0.5.0"
+    "rollup-plugin-sourcemaps": "0.5.0",
+    "rollup-plugin-typescript2": "0.27.0",
+    "typescript": "3.8.3"
   },
   "repository": {
     "directory": "packages/webchannel-wrapper",

packages/webchannel-wrapper/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "extends": "../../config/tsconfig.base.json",
+  "compilerOptions": {
+    "declaration": false,
+    "outDir": "dist",
+    "downlevelIteration": true,
+  }
+}

test.js

@@ -0,0 +1,16 @@
+/**
+ * @license
+ * Copyright 2020 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */