Package Exports

tapable
tapable/lib/AsyncParallelHook
tapable/lib/AsyncSeriesBailHook
tapable/lib/AsyncSeriesHook
tapable/lib/Hook
tapable/lib/HookMap
tapable/lib/SyncBailHook
tapable/lib/SyncHook
tapable/lib/Tapable

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (tapable) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

Tapable

The tapable packages exposes many Hook classes, which can be used to create hooks for plugins.

const {
    SyncHook,
    SyncBailHook,
    SyncWaterfallHook,
    SyncLoopHook,
    AsyncParallelHook,
    AsyncParallelBailHook,
    AsyncSequencialHook,
    AsyncSequencialBailHook,
    AsyncWaterfallHook
 } = require("tapable");

Usage

All Hook constructors take one optional argument, which is a list of argument names as strings.

const hook = new SyncHook(["arg1", "arg2", "arg3"]);

The best practice is to expose all hooks of a class in a hooks property:

class Car {
    constructor() {
        this.hooks = {
            accelerate: new SyncHook(["newSpeed"]),
            break: new SyncHook(),
            calculateRoutes: new AsyncParallelHook(["source", "target", "routesList"])
        };
    }

    /* ... */
}

Other people can now use these hooks:

const myCar = new Car();

// Use the tap method to add a consument
myCar.hooks.break.tap("WarningLampPlugin", () => warningLamp.on());

It's required to pass a name to identify the plugin/reason.

You may receive arguments:

myCar.hooks.accelerate.tap("LoggerPlugin", newSpeed => console.log(`Accelerating to ${newSpeed}`));

For sync hooks tap is the only valid method to add a plugin. Async hooks also support async plugins:

myCar.hooks.calculateRoutes.tapPromise("GoogleMapsPlugin", (source, target, routesList) => {
    // return a promise
    return google.maps.findRoute(source, target).then(route => {
        routesList.add(route);
    });
});
myCar.hooks.calculateRoutes.tapAsync("BingMapsPlugin", (source, target, routesList, callback) => {
    bing.findRoute(source, target, (err, route) => {
        if(err) return callback(err);
        routesList.add(route);
        // call the callback
        callback();
    });
});

// You can still use sync plugins
myCar.hooks.calculateRoutes.tap("CachedRoutesPlugin", (source, target, routesList) => {
    const cachedRoute = cache.get(source, target);
    if(cachedRoute)
        routesList.add(cachedRoute);
})

The class declaring these hooks need to call them:

class Car {
    /* ... */

    setSpeed(newSpeed) {
        this.hooks.accelerate.call(newSpeed);
    }

    useNavigationSystemPromise(source, target) {
        const routesList = new List();
        return this.hooks.calculateRoutes.promise(source, target, routesList).then(() => {
            return routesList.getRoutes();
        });
    }

    useNavigationSystemAsync(source, target, callback) {
        const routesList = new List();
        this.hooks.calculateRoutes.callAsync(source, target, routesList, err => {
            if(err) return callback(err);
            callback(null, routesList.getRoutes());
        });
    }
}

The Hook will compile a method with the most efficient way of running your plugins. It generates code depending on:

The number of registered plugins (none, one, many)
The kind of registered plugins (sync, async, promise)
The used call method (sync, async, promise)
The number of arguments
Whether interception is used

This ensures fastest possible execution.

Interception

All Hooks offer an additional interception API:

myCar.hooks.calculateRoutes.intercept({
    call: (source, target, routesList) => {
        console.log("Starting to calculate routes");
    },
    tap: (tapInfo) => {
        // tapInfo = { type: "promise", name: "GoogleMapsPlugin", fn: ... }
        console.log(`${tapInfo.name} is doing it's job`);
        return tapInfo; // may return a new tapInfo object
    }
})