Review

1. 2023-02-26 23:29
2. 2024-09-15

[!Summary] Github https://github.com/webpack/tapable

一、Introduction #

const {
	SyncHook,
	SyncBailHook,
	SyncWaterfallHook,
	SyncLoopHook,
	AsyncParallelHook,
	AsyncParallelBailHook,
	AsyncSeriesHook,
	AsyncSeriesBailHook,
	AsyncSeriesWaterfallHook,
	AsyncSeriesLoopHook,
} = require("tapable");

Each hook can be tapped with one or several functions. How they are executed depends on the hook type:

• Basic hook (without “Waterfall”, “Bail” or “Loop” in its name). This hook simply calls every function it tapped in a row.
• Waterfall. A waterfall hook also calls each tapped function in a row. Unlike the basic hook, it passes a return value from each function to the next function.
• Bail. A bail hook allows exiting early. When any of the tapped function returns anything, the bail hook will stop executing the remaining ones.
• Loop. When a plugin in a loop hook returns a non-undefined value the hook will restart from the first plugin. It will loop until all plugins return undefined.

Additionally, hooks can be synchronous or asynchronous. To reflect this, there’re “Sync”, “AsyncSeries”, and “AsyncParallel” hook classes:

• Sync. A sync hook can only be tapped with synchronous functions (using myHook.tap()). use myHook.call() trigger call.
• AsyncSeries. An async-series hook can be tapped with synchronous, callback-based and promise-based functions (using myHook.tap(), myHook.tapAsync() and myHook.tapPromise()). They call each async method in a row. use myHook.promise or myHook.callAsync trigger call.
• AsyncParallel. An async-parallel hook can also be tapped with synchronous, callback-based and promise-based functions (using myHook.tap(), myHook.tapAsync() and myHook.tapPromise()). However, they run each async method in parallel.

The hook type is reflected in its class name. E.g., AsyncSeriesWaterfallHook allows asynchronous functions and runs them in series, passing each function’s return value into the next function.

其他特性

• HookMap
• intercept

Usage #

npm install --save tapable

Reference #

1. tapable Github
2. 读一读 Tapable 源码