So, you've delved into writing your own Chrome extension. Maybe you've even already made one, but you still have a question: How can I use the current technology to do this? Well, as it turns out, it only takes a few extra steps!

In this tutorial, I am going to go over how to create a Chrome extension using NextJS! While this guide is tailored specifically for NextJS, I presume it would work well for Nuxt as well, but please let me know in the comments!

First up, we are going to create our NextJS application!

npx create-next-app && cd next-app
# or
yarn create next-app && cd next-app

At this point, you can install any extra dependencies you may wish to add (like Typescript or TailwindCSS).

This will set up some defaults for you, but we need to change them. First off, to build a NextJS app for a chrome extension, we need to use "next export". To do this, we are going to edit the scripts in package.json:

{
    "scripts": {
        "build": "next build && next export"
    }
}

You won't need the other two scripts. Let's remove them. You can also go in and delete your `pages/api` directory, as we won't be using them. 

Next, we need to create a "manifest.json" and place it in "public/". You will also need icons for this. There are several generators for this that you can find only, but here is a starter:

My Extesnion

My New Extension

From here, we can run "yarn build". This will create our app and export it to a static site in "out/". We'll run into a problem with this though, in that chrome extensions can't (for some reason) have underscores in their paths. 

Let's do some more tweaking to fix that! We will add a new script to "scripts" that change the directory in the code and the directory structure.

Sweet! Now double-check the "out" directory and make sure everything looks right. 

If everything looks good, you can go ahead and load the "out/" directory into chrome!

I'd be ending this a little short if I didn't suggest improving the developer experience of this. Having to run "yarn build" every time you make a change is annoying.

This is a convenient package that watches files based on different settings you give it and then runs an "npm script".

Below you'll find my suggested configuration for this. You'll want to tweak this based on your project settings.

That's it! If you have any problems getting this going, please reach out in the comments, or come chat with me in discord at https://discord.gg/FUhmvK7. I hope this has been helpful!

Don't forget to come and watch me stream either: https://twitch.tv/CryptikLemur.

I do programming streams during the day on Tuesday, Wednesday, and Thursday, so come on by!

So, you've delved into writing your own Chrome extension. Maybe you've even already made one, but you still have a question: How can I use more current technology to to this? Well, as it turns out, it only takes a few extra steps!

I've been working on a project at Underground Elephant that is a very very very heavy javascript project. It's heavily event-driven, but I have an issue with the lack of event priorities in jquery. The Symfony 2 Event Listener is a great example of what an event listener should look like, for a couple of reasons. First, and most importantly (to me at least), the events have a priority. Secondly, Events have specific classes that get passed with them, so you know exactly what to expect.

I wanted something like this for javascript, but there was really nothing out there for jQuery. In fact, Dave Methvin(@davemethvin), a member of the jQuery core team, made this comment about a year ago:

#QUOTE
We've discussed this before and decided it's not productive to have handlers that try to out-prioritize each other. You're welcome to write something like that implementation as a plugin, as long as it's understood that it uses internals that may change and break the code.
#ENDQUOTE

This was a little disappointing to me, but I can understand a little why they made this decision.

So, with all this, I decided to make a small little addon for jQuery that allows for creating custom events. The custom events can have priorities and require a defined "class" (as javascript uses it).

Without further ado, i present to you: Fusion Framework

As of right now, this framework only supports custom events.
You cannot use this for events that are meant to be bound to elements.

This framework requires jQuery 1.9 or higher.

Right now, there are only two built-in events. DOCUMENT_LOAD, and DOCUMENT_UNLOAD.
To use your own custom events, you need to add them to the event list, which can be done as follows:

#LANG:javascript
(function (fusion) {
    fusion.events.add('SOME_EVENT_NAME', fusion.event.extend({somevar: null}));

    // You can store those in classes too. For example, the DOCUMENT_LOAD stuff
    var func = fusion.event.extend({
        window: window,
        document: document,
    });

    fusion.events.add('DOCUMENT_LOAD', func);

})($.fn.fusion);

To bind to these events, we will be using the fuse method. Pretty simple, from the demo app:

You can get to the event's data with event.getData( [key] ).

#LANG:javascript
// Note, by default $f is an alias of $.fn.fusion

// Create your first event. This has a default priority of 50.
$f.fuse('DOCUMENT_LOAD', function (event) {
    event.getData('window').location.href += '#test';
});

// Later down the line in your app, you want something bound before the above.
// So we create another bind, but set the priority to something lower than 50 (5 here).
$f.fuse('DOCUMENT_LOAD', function (event) {
    event.getData('window').location.href += '#highesttest';
}, 5);

// Even later down, we want something bound after the other two events.
// So we create another bind, but set the priority to something higher than 50 (70 here).
$f.fuse('DOCUMENT_LOAD', function (event) {
    event.getData('window').location.href += '#test';
}, 70);

You now have three binds on the DOCUMENT_LOAD event.

To fire these events, just call the ignite method, and pass in the event class's variables. Super simple.

For example, the DOCUMENT_LOAD and DOCUMENT_UNLOAD events.

#LANG:javascript $(function () {     fusion.ignite('DOCUMENT_LOAD', {window: window, cheese: 'cheese'});     $(document).unload(function () {         fusion.ignite('DOCUMENT_UNLOAD', {window: window});     }); });

If you noticed, as a test, I've added cheese: 'cheese' to the DOCUMENT_LOAD event, to see if you could access that on the page.
You can test this yourself, but in the binds, you won't be able to access the cheese data, because it was never in the class properties.

If you would like to help with contributing, please do! Just fork this code, make your changes, and put in a pull request.
I would love for this framework to work with element bound events, but I don't have enough time to figure that out.

I have been working on a new cache implementation for the Symfony2 framework, and I needed a way to check if a named class inherited a given interface , so i wrote the following:

#LANG:php
<?php
function classInherits( $class, $inherit ) {
	if( is_object( $class ) ) {
		return ( $class instanceof $inherit );
	} elseif( is_string( $class ) ) {
		return (bool) in_array( $inherit, class_implements( $class ) );
	}

	throw new Exception( "First value must be the name of a valid class, or an instance of one." );
}

Aaron Scherer

Checking Named Class Inheritance

Related Posts

Creating a Chrome Extension with NextJS

jQuery Event Priority - Fusion Framework