Sometimes I need to make a small change to a composer package, often in a Symfony project. It is a really bad idea to just go into the vendor directory of the package and change some code. It’s much better to fork the corresponding repository, apply your change and build a new release. Then you can use that in a composer.json file.

Fork the repository

For the purpoe of demonstration I will create a customized version of Javier Eguiluz’s EasyAdmin bundle for Symfony. So go to the github page of the EasyAdmin bundle and click on the “Fork” button in the top right corner. Github will create a fork for you under your own user account. Clone that repository and make your changes. For this is one line in the file src/Form/Util/LegacyFormHelper.php as I mentioned in the last posting.

Build a new release

Now we’re ready to build a new release. Go to the “releases” tab in your forked repository and click on “Draft a new release”. Define a new tag version (unimportant how you call it, I normally just count up the original release version). I normally enter something like “for private use only” into the “Release title” field but you just can leave that empty. Once you’re done you can submit via “Publish release”. You will be brought back to the release list and see your new release tagged with a green label saying “Latest release”. You just built your first release \o/

Use the release in a composer.json file

You now can change your composer.json file. First you need to add the repository. By default composer will look up the packagist repository. If you define a different one in the json file this local one will be searched first before falling back to the public repo. So we need to create a repository section and list the github repository. Mine looks like this:

"repositories": [
    { "type": "vcs", "url": "git@github.com:vmgforks/EasyAdminBundle.git" }
],

The type is “vcs” (version control system) and the URL is your forked repository. I like to keep forks in a organization of its own called “vmgforks”. Now we can require the package by using its original name and the required version just is “*”:

"javiereguiluz/easyadmin-bundle": "*",

Now update the composer.lock and download and install the package by:

composer update

Now you can check if the change made it to the vendor directory.