webpack/examples/common-chunk-grandchildren/README.md

527 lines
16 KiB
Markdown

This example illustrates how common modules from deep ancestors of an entry point can be split into a separate common chunk
- `pageA` and `pageB` are dynamically required
- `pageC` and `pageA` both require the `reusableComponent`
- `pageB` dynamically requires `PageC`
You can see that webpack outputs five files/chunks:
- `output.js` is the entry chunk and contains
- the module system
- chunk loading logic
- the entry point `example.js`
- `0.output.js` is an additional chunk
- module `reusableComponent`
- `1.output.js` is an additional chunk
- module `pageB`
- `2.output.js` is an additional chunk
- module `pageA`
- `3.output.js` is an additional chunk
- module `pageC`
# example.js
```javascript
var main = function() {
console.log("Main class");
require.ensure([], () => {
const page = require("./pageA");
page();
});
require.ensure([], () => {
const page = require("./pageB");
page();
});
};
main();
```
# pageA.js
```javascript
var reusableComponent = require("./reusableComponent");
module.exports = function() {
console.log("Page A");
reusableComponent();
};
```
# pageB.js
```javascript
module.exports = function() {
console.log("Page B");
require.ensure([], ()=>{
const page = require("./pageC");
page();
});
};
```
# pageC.js
```javascript
var reusableComponent = require("./reusableComponent");
module.exports = function() {
console.log("Page C");
reusableComponent();
};
```
# reusableComponent.js
```javascript
module.exports = function() {
console.log("reusable Component");
};
```
# webpack.config.js
```javascript
"use strict";
const path = require("path");
module.exports = {
// mode: "development || "production",
entry: {
main: ["./example.js"]
},
optimization: {
splitChunks: {
minSize: 0 // This example is too small, in practice you can use the defaults
},
occurrenceOrder: true // To keep filename consistent between different modes (for example building only)
},
output: {
path: path.resolve(__dirname, "dist"),
filename: "output.js"
}
};
```
# dist/output.js
<details><summary><code>/******/ (function(modules) { /* webpackBootstrap */ })</code></summary>
```javascript
/******/ (function(modules) { // webpackBootstrap
/******/ // install a JSONP callback for chunk loading
/******/ function webpackJsonpCallback(data) {
/******/ var chunkIds = data[0];
/******/ var moreModules = data[1];
/******/
/******/
/******/ // add "moreModules" to the modules object,
/******/ // then flag all "chunkIds" as loaded and fire callback
/******/ var moduleId, chunkId, i = 0, resolves = [];
/******/ for(;i < chunkIds.length; i++) {
/******/ chunkId = chunkIds[i];
/******/ if(installedChunks[chunkId]) {
/******/ resolves.push(installedChunks[chunkId][0]);
/******/ }
/******/ installedChunks[chunkId] = 0;
/******/ }
/******/ for(moduleId in moreModules) {
/******/ if(Object.prototype.hasOwnProperty.call(moreModules, moduleId)) {
/******/ modules[moduleId] = moreModules[moduleId];
/******/ }
/******/ }
/******/ if(parentJsonpFunction) parentJsonpFunction(data);
/******/
/******/ while(resolves.length) {
/******/ resolves.shift()();
/******/ }
/******/
/******/ };
/******/
/******/
/******/ // The module cache
/******/ var installedModules = {};
/******/
/******/ // object to store loaded and loading chunks
/******/ // undefined = chunk not loaded, null = chunk preloaded/prefetched
/******/ // Promise = chunk loading, 0 = chunk loaded
/******/ var installedChunks = {
/******/ 1: 0
/******/ };
/******/
/******/
/******/
/******/ // script path function
/******/ function jsonpScriptSrc(chunkId) {
/******/ return __webpack_require__.p + "" + chunkId + ".output.js"
/******/ }
/******/
/******/ // The require function
/******/ function __webpack_require__(moduleId) {
/******/
/******/ // Check if module is in cache
/******/ if(installedModules[moduleId]) {
/******/ return installedModules[moduleId].exports;
/******/ }
/******/ // Create a new module (and put it into the cache)
/******/ var module = installedModules[moduleId] = {
/******/ i: moduleId,
/******/ l: false,
/******/ exports: {}
/******/ };
/******/
/******/ // Execute the module function
/******/ modules[moduleId].call(module.exports, module, module.exports, __webpack_require__);
/******/
/******/ // Flag the module as loaded
/******/ module.l = true;
/******/
/******/ // Return the exports of the module
/******/ return module.exports;
/******/ }
/******/
/******/ // This file contains only the entry chunk.
/******/ // The chunk loading function for additional chunks
/******/ __webpack_require__.e = function requireEnsure(chunkId) {
/******/ var promises = [];
/******/
/******/
/******/ // JSONP chunk loading for javascript
/******/
/******/ var installedChunkData = installedChunks[chunkId];
/******/ if(installedChunkData !== 0) { // 0 means "already installed".
/******/
/******/ // a Promise means "currently loading".
/******/ if(installedChunkData) {
/******/ promises.push(installedChunkData[2]);
/******/ } else {
/******/ // setup Promise in chunk cache
/******/ var promise = new Promise(function(resolve, reject) {
/******/ installedChunkData = installedChunks[chunkId] = [resolve, reject];
/******/ });
/******/ promises.push(installedChunkData[2] = promise);
/******/
/******/ // start chunk loading
/******/ var script = document.createElement('script');
/******/ var onScriptComplete;
/******/
/******/ script.charset = 'utf-8';
/******/ script.timeout = 120;
/******/ if (__webpack_require__.nc) {
/******/ script.setAttribute("nonce", __webpack_require__.nc);
/******/ }
/******/ script.src = jsonpScriptSrc(chunkId);
/******/
/******/ onScriptComplete = function (event) {
/******/ // avoid mem leaks in IE.
/******/ script.onerror = script.onload = null;
/******/ clearTimeout(timeout);
/******/ var chunk = installedChunks[chunkId];
/******/ if(chunk !== 0) {
/******/ if(chunk) {
/******/ var errorType = event && (event.type === 'load' ? 'missing' : event.type);
/******/ var realSrc = event && event.target && event.target.src;
/******/ var error = new Error('Loading chunk ' + chunkId + ' failed.\n(' + errorType + ': ' + realSrc + ')');
/******/ error.type = errorType;
/******/ error.request = realSrc;
/******/ chunk[1](error);
/******/ }
/******/ installedChunks[chunkId] = undefined;
/******/ }
/******/ };
/******/ var timeout = setTimeout(function(){
/******/ onScriptComplete({ type: 'timeout', target: script });
/******/ }, 120000);
/******/ script.onerror = script.onload = onScriptComplete;
/******/ document.head.appendChild(script);
/******/ }
/******/ }
/******/ return Promise.all(promises);
/******/ };
/******/
/******/ // expose the modules object (__webpack_modules__)
/******/ __webpack_require__.m = modules;
/******/
/******/ // expose the module cache
/******/ __webpack_require__.c = installedModules;
/******/
/******/ // define getter function for harmony exports
/******/ __webpack_require__.d = function(exports, name, getter) {
/******/ if(!__webpack_require__.o(exports, name)) {
/******/ Object.defineProperty(exports, name, { enumerable: true, get: getter });
/******/ }
/******/ };
/******/
/******/ // define __esModule on exports
/******/ __webpack_require__.r = function(exports) {
/******/ if(typeof Symbol !== 'undefined' && Symbol.toStringTag) {
/******/ Object.defineProperty(exports, Symbol.toStringTag, { value: 'Module' });
/******/ }
/******/ Object.defineProperty(exports, '__esModule', { value: true });
/******/ };
/******/
/******/ // create a fake namespace object
/******/ // mode & 1: value is a module id, require it
/******/ // mode & 2: merge all properties of value into the ns
/******/ // mode & 4: return value when already ns object
/******/ // mode & 8|1: behave like require
/******/ __webpack_require__.t = function(value, mode) {
/******/ if(mode & 1) value = __webpack_require__(value);
/******/ if(mode & 8) return value;
/******/ if((mode & 4) && typeof value === 'object' && value && value.__esModule) return value;
/******/ var ns = Object.create(null);
/******/ __webpack_require__.r(ns);
/******/ Object.defineProperty(ns, 'default', { enumerable: true, value: value });
/******/ if(mode & 2 && typeof value != 'string') for(var key in value) __webpack_require__.d(ns, key, function(key) { return value[key]; }.bind(null, key));
/******/ return ns;
/******/ };
/******/
/******/ // getDefaultExport function for compatibility with non-harmony modules
/******/ __webpack_require__.n = function(module) {
/******/ var getter = module && module.__esModule ?
/******/ function getDefault() { return module['default']; } :
/******/ function getModuleExports() { return module; };
/******/ __webpack_require__.d(getter, 'a', getter);
/******/ return getter;
/******/ };
/******/
/******/ // Object.prototype.hasOwnProperty.call
/******/ __webpack_require__.o = function(object, property) { return Object.prototype.hasOwnProperty.call(object, property); };
/******/
/******/ // __webpack_public_path__
/******/ __webpack_require__.p = "dist/";
/******/
/******/ // on error function for async loading
/******/ __webpack_require__.oe = function(err) { console.error(err); throw err; };
/******/
/******/ var jsonpArray = window["webpackJsonp"] = window["webpackJsonp"] || [];
/******/ var oldJsonpFunction = jsonpArray.push.bind(jsonpArray);
/******/ jsonpArray.push = webpackJsonpCallback;
/******/ jsonpArray = jsonpArray.slice();
/******/ for(var i = 0; i < jsonpArray.length; i++) webpackJsonpCallback(jsonpArray[i]);
/******/ var parentJsonpFunction = oldJsonpFunction;
/******/
/******/
/******/ // Load entry module and return exports
/******/ return __webpack_require__(__webpack_require__.s = 0);
/******/ })
/************************************************************************/
```
</details>
```javascript
/******/ ([
/* 0 */
/*!**************************!*\
!*** multi ./example.js ***!
\**************************/
/*! no static exports found */
/***/ (function(module, exports, __webpack_require__) {
module.exports = __webpack_require__(/*! ./example.js */1);
/***/ }),
/* 1 */
/*!********************!*\
!*** ./example.js ***!
\********************/
/*! no static exports found */
/***/ (function(module, exports, __webpack_require__) {
var main = function() {
console.log("Main class");
Promise.all(/*! require.ensure */[__webpack_require__.e(0), __webpack_require__.e(2)]).then((() => {
const page = __webpack_require__(/*! ./pageA */ 2);
page();
}).bind(null, __webpack_require__)).catch(__webpack_require__.oe);
__webpack_require__.e(/*! require.ensure */ 3).then((() => {
const page = __webpack_require__(/*! ./pageB */ 3);
page();
}).bind(null, __webpack_require__)).catch(__webpack_require__.oe);
};
main();
/***/ })
/******/ ]);
```
# dist/0.output.js
```javascript
(window["webpackJsonp"] = window["webpackJsonp"] || []).push([[0],{
/***/ 4:
/*!******************************!*\
!*** ./reusableComponent.js ***!
\******************************/
/*! no static exports found */
/***/ (function(module, exports) {
module.exports = function() {
console.log("reusable Component");
};
/***/ })
}]);
```
# dist/2.output.js
```javascript
(window["webpackJsonp"] = window["webpackJsonp"] || []).push([[2],{
/***/ 2:
/*!******************!*\
!*** ./pageA.js ***!
\******************/
/*! no static exports found */
/***/ (function(module, exports, __webpack_require__) {
var reusableComponent = __webpack_require__(/*! ./reusableComponent */ 4);
module.exports = function() {
console.log("Page A");
reusableComponent();
};
/***/ })
}]);
```
# dist/3.output.js
```javascript
(window["webpackJsonp"] = window["webpackJsonp"] || []).push([[3],{
/***/ 3:
/*!******************!*\
!*** ./pageB.js ***!
\******************/
/*! no static exports found */
/***/ (function(module, exports, __webpack_require__) {
module.exports = function() {
console.log("Page B");
Promise.all(/*! require.ensure */[__webpack_require__.e(0), __webpack_require__.e(4)]).then((()=>{
const page = __webpack_require__(/*! ./pageC */ 5);
page();
}).bind(null, __webpack_require__)).catch(__webpack_require__.oe);
};
/***/ })
}]);
```
# dist/4.output.js
```javascript
(window["webpackJsonp"] = window["webpackJsonp"] || []).push([[4],{
/***/ 5:
/*!******************!*\
!*** ./pageC.js ***!
\******************/
/*! no static exports found */
/***/ (function(module, exports, __webpack_require__) {
var reusableComponent = __webpack_require__(/*! ./reusableComponent */ 4);
module.exports = function() {
console.log("Page C");
reusableComponent();
};
/***/ })
}]);
```
# Info
## Unoptimized
```
Hash: 0a1b2c3d4e5f6a7b8c9d
Version: webpack 4.29.6
Asset Size Chunks Chunk Names
0.output.js 337 bytes 0 [emitted]
2.output.js 408 bytes 2 [emitted]
3.output.js 542 bytes 3 [emitted]
4.output.js 408 bytes 4 [emitted]
output.js 8.74 KiB 1 [emitted] main
Entrypoint main = output.js
chunk {0} 0.output.js 69 bytes <{1}> <{3}> ={2}= ={4}= [rendered] split chunk (cache group: default)
> [1] ./example.js 3:1-6:3
> [3] ./pageB.js 3:1-6:3
[4] ./reusableComponent.js 69 bytes {0} [built]
cjs require ./reusableComponent [2] ./pageA.js 1:24-54
cjs require ./reusableComponent [5] ./pageC.js 1:24-54
chunk {1} output.js (main) 248 bytes >{0}< >{2}< >{3}< [entry] [rendered]
> main
[0] multi ./example.js 28 bytes {1} [built]
multi entry
[1] ./example.js 220 bytes {1} [built]
single entry ./example.js [0] multi ./example.js main[0]
chunk {2} 2.output.js 136 bytes <{1}> ={0}= [rendered]
> [1] ./example.js 3:1-6:3
[2] ./pageA.js 136 bytes {2} [built]
cjs require ./pageA [1] ./example.js 4:15-33
chunk {3} 3.output.js 133 bytes <{1}> >{0}< >{4}< [rendered]
> [1] ./example.js 7:1-10:3
[3] ./pageB.js 133 bytes {3} [built]
cjs require ./pageB [1] ./example.js 8:15-33
chunk {4} 4.output.js 136 bytes <{3}> ={0}= [rendered]
> [3] ./pageB.js 3:1-6:3
[5] ./pageC.js 136 bytes {4} [built]
cjs require ./pageC [3] ./pageB.js 4:15-33
```
## Production mode
```
Hash: 0a1b2c3d4e5f6a7b8c9d
Version: webpack 4.29.6
Asset Size Chunks Chunk Names
0.output.js 133 bytes 0 [emitted]
2.output.js 138 bytes 2 [emitted]
3.output.js 198 bytes 3 [emitted]
4.output.js 138 bytes 4 [emitted]
output.js 2.13 KiB 1 [emitted] main
Entrypoint main = output.js
chunk {0} 0.output.js 69 bytes <{1}> <{3}> ={2}= ={4}= [rendered] split chunk (cache group: default)
> [1] ./example.js 3:1-6:3
> [3] ./pageB.js 3:1-6:3
[4] ./reusableComponent.js 69 bytes {0} [built]
cjs require ./reusableComponent [2] ./pageA.js 1:24-54
cjs require ./reusableComponent [5] ./pageC.js 1:24-54
chunk {1} output.js (main) 248 bytes >{0}< >{2}< >{3}< [entry] [rendered]
> main
[0] multi ./example.js 28 bytes {1} [built]
multi entry
[1] ./example.js 220 bytes {1} [built]
single entry ./example.js [0] multi ./example.js main[0]
chunk {2} 2.output.js 136 bytes <{1}> ={0}= [rendered]
> [1] ./example.js 3:1-6:3
[2] ./pageA.js 136 bytes {2} [built]
cjs require ./pageA [1] ./example.js 4:15-33
chunk {3} 3.output.js 133 bytes <{1}> >{0}< >{4}< [rendered]
> [1] ./example.js 7:1-10:3
[3] ./pageB.js 133 bytes {3} [built]
cjs require ./pageB [1] ./example.js 8:15-33
chunk {4} 4.output.js 136 bytes <{3}> ={0}= [rendered]
> [3] ./pageB.js 3:1-6:3
[5] ./pageC.js 136 bytes {4} [built]
cjs require ./pageC [3] ./pageB.js 4:15-33
```