From f3bbef1ce33b31939aad2593ba68158d0852d984 Mon Sep 17 00:00:00 2001
From: Aleksey Smolenchuk <aleksey@uber.com>
Date: Wed, 17 Apr 2019 10:32:03 -0700
Subject: [PATCH] Add brotli and svgo flags; allow babel excludes;
 overrideWebpackConfig option in .fusionrc.js; remove scary messages

---
 .gitignore                  |  1 +
 README.md                   |  5 ++--
 build/compiler.js           | 14 ++++++++---
 build/get-webpack-config.js | 34 ++++++++++++++++++++++-----
 build/load-fusionrc.js      | 25 +++++++++-----------
 commands/build.js           |  6 +++++
 docs/fusionrc.md            | 46 +++++++++++++++++++++++++++++++++----
 7 files changed, 101 insertions(+), 30 deletions(-)

diff --git a/.gitignore b/.gitignore
index e74b1da9..7f289cd8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,4 @@ node_modules/
 .nyc_output/
 yarn-error.log
 coverage/
+.vscode
diff --git a/README.md b/README.md
index 3cc54f61..a0cf9050 100644
--- a/README.md
+++ b/README.md
@@ -6,8 +6,6 @@ The CLI interface for Fusion.js
 
 The `fusion-cli` package is responsible for orchestrating compile-time configuration for server and browser bundles, as well as development, test and production variations. It provides a standardized Babel configuration that includes async/await support as well as stage 3+ Ecmascript features.
 
-Due to the complexity involved in configuring many permutations of configurations, Fusion.js does not support custom `webpack.config`. This design decision allows Fusion.js to eventually move away from Webpack if faster and better bundlers become available. Additionally, it allows Fusion.js to make changes to the internal webpack configuration without the concern of breaking users customizations. If you run into a situation where you feel you need to make a webpack customization, please reach out to us on [slack](https://join.slack.com/t/fusionjs/shared_invite/enQtMzk3NjM0MTg0MTI4LWJhNzVjYjk5ZDVlYWIxZWViMjA3YzE5OTc4YWZkNzBkZmNkYmJkMDYyOGEzODEwMzRmMWExMzc1NDIzMmY2NDQ) or create an issue describing your use case.
-
 The CLI is also responsible for hot module reloading in development mode, and for running the web server.
 
 ### Installation
@@ -43,6 +41,9 @@ The CLI API can be most easily run through the Yarn or NPX CLI, e.g. `yarn fusio
   - `--log-level`: Log level to output to console `[default: "info"]`
   - `--forceLegacyBuild`: Force enable legacy build. By default not compiled in dev.
   - `--perserve-names`: Disable name mangling during script minification
+  - `--no-zofpli`: Disable zopfli compression plugin
+  - `--no-brotli`: Disable brotli compression plugin
+  - `--no-svgo`: Disable svgo optimization plugin
 
 <!--
 * `fusion profile [--environment] [--watch] [--file-count]`: Profile your application
diff --git a/build/compiler.js b/build/compiler.js
index 30b404ce..381709a8 100644
--- a/build/compiler.js
+++ b/build/compiler.js
@@ -63,8 +63,8 @@ function getStatsLogger({dir, logger, env}) {
 
     if (err) {
       logger.error(err.stack || err);
-      if (err.details) {
-        logger.error(err.details);
+      if ((err /*: any */).details) {
+        logger.error((err /*: any */).details);
       }
       return;
     }
@@ -119,6 +119,8 @@ type CompilerOpts = {
   logger?: any,
   preserveNames?: boolean,
   zopfli?: boolean,
+  brotli?: boolean,
+  svgo?: boolean,
   minify?: boolean
 };
 */
@@ -133,6 +135,8 @@ function Compiler(
     watch = false,
     logger = console,
     zopfli = true,
+    brotli = true,
+    svgo = true,
     minify = true,
   } /*: CompilerOpts */
 ) /*: CompilerType */ {
@@ -170,6 +174,8 @@ function Compiler(
     legacyPkgConfig,
     preserveNames,
     zopfli,
+    brotli,
+    svgo,
     minify,
   };
 
@@ -180,7 +186,9 @@ function Compiler(
 
   const statsLogger = getStatsLogger({dir, logger, env});
 
-  this.on = (type, callback) => compiler.hooks[type].tap('compiler', callback);
+  this.on = (type, callback) =>
+    (compiler /*: any */).hooks[type]
+      .tap('compiler', callback);
   this.start = cb => {
     cb = cb || function noop(err, stats) {};
     // Handler may be called multiple times by `watch`
diff --git a/build/get-webpack-config.js b/build/get-webpack-config.js
index cb781028..0b1ef464 100644
--- a/build/get-webpack-config.js
+++ b/build/get-webpack-config.js
@@ -73,6 +73,10 @@ import type {
   FusionRC
 } from "./load-fusionrc.js";
 
+import type {
+  WebpackOptions 
+} from "webpack";
+
 export type WebpackConfigOpts = {|
   id: $Keys<typeof COMPILATIONS>,
   dir: string,
@@ -81,6 +85,8 @@ export type WebpackConfigOpts = {|
   watch: boolean,
   preserveNames: boolean,
   zopfli: boolean,
+  brotli: boolean,
+  svgo: boolean,
   minify: boolean,
   state: {
     clientChunkMetadata: ClientChunkMetadataState,
@@ -108,9 +114,12 @@ function getWebpackConfig(opts /*: WebpackConfigOpts */) {
     state,
     fusionConfig,
     zopfli,
+    brotli,
+    svgo,
     minify,
     legacyPkgConfig = {},
   } = opts;
+
   const main = 'src/main.js';
 
   if (!fs.existsSync(path.join(dir, main))) {
@@ -197,7 +206,8 @@ function getWebpackConfig(opts /*: WebpackConfigOpts */) {
         target: runtime === 'server' ? 'node-bundled' : 'browser-legacy',
         specOnly: false,
       });
-  return {
+
+  const webpackConfig = {
     name: runtime,
     target: {server: 'node', client: 'web', sw: 'webworker'}[runtime],
     entry: {
@@ -285,7 +295,9 @@ function getWebpackConfig(opts /*: WebpackConfigOpts */) {
         runtime === 'server' && {
           compiler: id => id === 'server',
           test: JS_EXT_PATTERN,
-          exclude: EXCLUDE_TRANSPILATION_PATTERNS,
+          exclude:
+            (fusionConfig.babel && fusionConfig.babel.exclude) ||
+            EXCLUDE_TRANSPILATION_PATTERNS,
           use: [
             {
               loader: babelLoader.path,
@@ -315,7 +327,9 @@ function getWebpackConfig(opts /*: WebpackConfigOpts */) {
         (runtime === 'client' || runtime === 'sw') && {
           compiler: id => id === 'client' || id === 'sw',
           test: JS_EXT_PATTERN,
-          exclude: EXCLUDE_TRANSPILATION_PATTERNS,
+          exclude:
+            (fusionConfig.babel && fusionConfig.babel.exclude) ||
+            EXCLUDE_TRANSPILATION_PATTERNS,
           use: [
             {
               loader: babelLoader.path,
@@ -345,7 +359,9 @@ function getWebpackConfig(opts /*: WebpackConfigOpts */) {
         runtime === 'client' && {
           compiler: id => id === 'client-legacy',
           test: JS_EXT_PATTERN,
-          exclude: EXCLUDE_TRANSPILATION_PATTERNS,
+          exclude:
+            (fusionConfig.babel && fusionConfig.babel.exclude) ||
+            EXCLUDE_TRANSPILATION_PATTERNS,
           use: [
             {
               loader: babelLoader.path,
@@ -457,8 +473,8 @@ function getWebpackConfig(opts /*: WebpackConfigOpts */) {
             state.i18nManifest
           ),
       !dev && zopfli && zopfliWebpackPlugin,
-      !dev && brotliWebpackPlugin,
-      !dev && svgoWebpackPlugin,
+      !dev && brotli && brotliWebpackPlugin,
+      !dev && svgo && svgoWebpackPlugin,
       // In development, skip the emitting phase on errors to ensure there are
       // no assets emitted that include errors. This fixes an issue with hot reloading
       // server side code and recovering from errors correctly. We only want to do this
@@ -580,6 +596,12 @@ function getWebpackConfig(opts /*: WebpackConfigOpts */) {
           : undefined,
     },
   };
+
+  if (fusionConfig.overrideWebpackConfig) {
+    return fusionConfig.overrideWebpackConfig(webpackConfig);
+  }
+
+  return webpackConfig;
 }
 
 // Allow overrides with a warning for `dev` command. In production builds, throw if NODE_ENV is not `production`.
diff --git a/build/load-fusionrc.js b/build/load-fusionrc.js
index 5d20f9d0..3d7e4674 100644
--- a/build/load-fusionrc.js
+++ b/build/load-fusionrc.js
@@ -16,11 +16,16 @@ const chalk = require('chalk');
 let loggedNotice = false;
 
 /*::
+import type {
+  WebpackOptions 
+} from "webpack";
+
 export type FusionRC = {
-  babel?: {plugins?: Array<any>, presets?: Array<any>},
+  babel?: {plugins?: Array<any>, presets?: Array<any>, exclude?: mixed},
   assumeNoImportSideEffects?: boolean,
   experimentalCompile?: boolean,
   nodeBuiltins?: {[string]: any},
+  overrideWebpackConfig:? (any) => any
 };
 */
 
@@ -33,17 +38,6 @@ module.exports = function validateConfig(dir /*: string */) /*: FusionRC */ {
     if (!isValid(config)) {
       throw new Error('.fusionrc.js is invalid');
     }
-    if (!loggedNotice && config.babel) {
-      console.log(chalk.dim('Using custom Babel config from .fusionrc.js'));
-      console.warn(
-        chalk.yellow(
-          'Warning: custom Babel config is an',
-          chalk.bold.underline('unstable API'),
-          'and may be not be supported in future releases. Use at your own risk.'
-        )
-      );
-      loggedNotice = true;
-    }
   } else {
     config = {};
   }
@@ -62,6 +56,7 @@ function isValid(config) {
         'assumeNoImportSideEffects',
         'experimentalCompile',
         'nodeBuiltins',
+        'overrideWebpackConfig',
       ].includes(key)
     )
   ) {
@@ -70,10 +65,12 @@ function isValid(config) {
 
   if (
     config.babel &&
-    !Object.keys(config.babel).every(el => ['plugins', 'presets'].includes(el))
+    !Object.keys(config.babel).every(el =>
+      ['plugins', 'presets', 'exclude'].includes(el)
+    )
   ) {
     throw new Error(
-      `Only "plugins" and "presets" are supported in fusionrc.js babel config`
+      `Only "plugins", "presets", and "exclude" are supported in fusionrc.js babel config`
     );
   }
 
diff --git a/commands/build.js b/commands/build.js
index 0ce8aa37..e6bc134f 100644
--- a/commands/build.js
+++ b/commands/build.js
@@ -19,6 +19,8 @@ exports.run = async function(
     preserveNames,
     logLevel,
     zopfli,
+    brotli,
+    svgo,
     minify,
   } /*: {
     dir: string,
@@ -26,6 +28,8 @@ exports.run = async function(
     preserveNames: boolean,
     logLevel: string,
     zopfli: boolean,
+    brotli: boolean,
+    svgo: boolean,
     minify: boolean
   }*/
 ) {
@@ -45,6 +49,8 @@ exports.run = async function(
     logger,
     preserveNames,
     zopfli,
+    brotli,
+    svgo,
     minify,
   });
 
diff --git a/docs/fusionrc.md b/docs/fusionrc.md
index e0137d09..d8a44c9a 100644
--- a/docs/fusionrc.md
+++ b/docs/fusionrc.md
@@ -6,7 +6,7 @@ This configuration object supports the following fields:
 
 ## `babel`
 
-### Adding plugins/presets
+### Adding plugins/presets and excluding files from babel compilation
 
 For example, to add your own Babel plugins/preset:
 
@@ -14,14 +14,12 @@ For example, to add your own Babel plugins/preset:
 module.exports = {
   babel: {
     presets: ["some-babel-preset"],
-    plugins: ["some-babel-plugin"]
+    plugins: ["some-babel-plugin"],
+    exclude: moduleName => /\/node_modules\//.test(moduleName)
   }
 };
 ```
 
-**Please note that custom Babel config is an unstable API and may not be supported in future releases.**
-
-
 ## `assumeNoImportSideEffects`
 
 By default this is `false`.
@@ -48,3 +46,41 @@ module.exports = {
   }
 };
 ```
+
+## `overrideWebpackConfig`
+
+Allows to customize [webpack configuration](https://webpack.js.org/concepts). 
+
+Pass a function that takes a [`webpackConfig`](https://webpack.js.org/configuration/) object created by fusion and return a config with any modifications supported by webpack.
+
+Example:
+
+```js
+const SimpleProgressPlugin = require('simple-progress-webpack-plugin');
+
+module.exports = {
+  overrideWebpackConfig: (webpackConfig) => {
+    // Debug things:
+    console.log(webpackConfig);
+
+    // Pass your own plugins:
+    webpackConfig.plugins = webpackConfig.plugins.map(plugin => {
+      // console.log(plugin.constructor.name);
+
+      if (plugin.constructor.name === 'ProgressPlugin') {
+        return new SimpleProgressPlugin({
+          format: 'expanded'
+        })
+      }
+
+      return plugin;
+    });
+    
+    // Don't forget to return it
+    return webpackConfig;
+  }
+};
+```
+
+
+