Bullet Pub-Sub Library

Bullet is an ultra lightweight and simple to use pub-sub library with zero dependencies, AMD/module support and an intuitive API.
It was built to facilitate a simple and consistent system of communication across web applications and includes only the bare essentials typically needed to achieve this.

Usage

Firstly, grab either the minified, or non-minified source from Github.

Alternatively, you can install via npm with the following command in your command prompt:

npm install bullet-pubsub --save

Or you can install via Bower instead, if that’s your thing:

bower install bullet

Include Bullet in your application

<script type="application/javascript" src="path/to/bullet.min.js"></script>

If using CommonJS then simply require Bullet as per usual:

var Bullet = require("bullet-pubsub");

API

.on()

Bullet.on("someMessageName", callback);

Register a callback function to get called whenever the specified message is triggered.

Example usage:

function helloCallback () {
    console.log("hello there :)");
}

// Register the 'helloCallback' function to be called whenever the 'hello' message is triggered:

Bullet.on("hello", helloCallback);


// Somewhere later in the application...


// Trigger the 'hello' message – Bullet will call the 'helloCallback' function:

Bullet.trigger("hello");

.off()

Bullet.off("someMessageName"[, callback]);

Remove either all callback functions or a specific callback function registered against the specified message.

Example usage:

function helloCallback () {
    console.log("hello there :)");
}

function anotherCallback () {
    console.log("hello again :)");
}


Bullet.on("hello", helloCallback);
Bullet.on("hello", anotherCallback);


// Somewhere later in the application...


// Trigger the 'hello' message – Bullet will call both the 'helloCallback' and 'anotherCallback' functions:

Bullet.trigger("hello");


// Remove all callback functions associated with the 'hello' message:
Bullet.off("hello");

// Attempt to trigger the 'hello' message again – Bullet won't call any functions:
Bullet.trigger("hello");

Example usage removing a specific callback:

function helloCallback () {
    console.log("hello there :)");
}

function anotherCallback () {
    console.log("hello again :)");
}


Bullet.on("hello", helloCallback);
Bullet.on("hello", anotherCallback);


// Somewhere later in the application...


// Trigger the 'hello' message – Bullet will call both the 'helloCallback' and 'anotherCallback' functions:

Bullet.trigger("hello");


// Remove only the 'anotherCallback' function associated with the 'hello' message:
Bullet.off("hello", anotherCallback);

// Trigger the 'hello' message again – Bullet will only call the 'helloCallback' function:
Bullet.trigger("hello");

.once()

Bullet.once("someMessageName", callback);

This function behaves in the same way as the the ‘on’ function, except that – once registered – the callback function will only be called a single time when the specified message is triggered.

Example usage:

function helloCallback () {
    console.log("hello there :)");
}


// Register the 'helloCallback' function to be called whenever the 'hello' message is triggered:

Bullet.once("hello", helloCallback);


// Somewhere later in the application...


// Trigger the 'hello' message – Bullet will call the 'helloCallback' function:

Bullet.trigger("hello");


// Attempt to trigger the 'hello' message again – Bullet won't call any functions this time:

Bullet.trigger("hello");

.trigger()

Bullet.trigger("someMessageName"[, data]);

This function will call all callback functions registered against the specified message, optionally passing in custom data as a payload.

Example usage:

function helloCallback () {
    console.log("hello there :)");
}


// Register the 'helloCallback' function to be called whenever the 'hello' message is triggered:

Bullet.on("hello", helloCallback);


// Somewhere later in the application...


// Trigger the 'hello' message – Bullet will call the 'helloCallback' function:

Bullet.trigger("hello");

Example usage with custom data:

function userAddedCallback (data) {
    console.log(data);
}


// Register the 'userAddedCallback' function to be called whenever the 'user-added' message is triggered:

Bullet.on("user-added", userAddedCallback);


// Somewhere later in the application...


// Create some custom data:

var customData = {
    someProp : "bro",
    someOtherProp : "awesome!"
};


// Trigger the 'user-added' message – Bullet will call the 'helloCallback' function and
// pass in the custom data that you created, which will be sent to the function as a parameter:

Bullet.trigger("user-added", customData);

About the Project

Bullet was developed and is currently maintained by Ivan Hayes.

Head over to the Github project page to find out more. Go ahead and star the project to keep up with its latest developments 🙂

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