Using Composer to Autoload ZF Modules

One aspect of Zend Framework 3, we paid particular focus on was leveraging the Composer ecosystem. We now provide a number of Composer plugins for handling things such as initial project installation, registering installed modules with the application, and more. It's the "more" I particularly want to talk about.

Registering modules on install

With ZF2, we were able to realize the ability to install third-party modules into existing applications, enabling a module ecosystem. The standard mantra for install has been:

1. Install module: composer require some/module
2. Register module with application: edit config/(application|modules).config.php and add Some\Module to the list of modules.

This second item has been problematic:

• Easy to forget
• Easy to introduce a typo

For the v3 release, we wanted to solve this if we could. We were able to do so via a Composer plugin, zend-component-installer.

Module authors may add some metadata to their package now, like the following:

"extra": {
  "zf": {
    "module": "Some\\Module"
  }
}

and, if the plugin is present in the user's application, on installation, it will register the package as a module with the application! (Moreover, if you later remove the package, it will remove it!)

We also added rules to allow specifying a package as a component; in this case, the module is added to the top of the module list, to ensure that userland modules can override its settings.

This ability to make a common task turn-key via Composer makes me happy.

Autoloading your own modules via Composer

Recently, while working on Apigility, a collaborator made a suggestion: "We recommend using Composer for autoloading, and yet Apigility creates modules that use the default module autoloading capabilities; couldn't we create a utility for enabling Composer autoloading of a generated module?"

This turned out to be really easy to accomplish, and we ended up creating a new package, zfcampus/zf-composer-autoloading, to make it re-usable.

Let's say you've created a new module in your ZF or Apigility application, named Blog. Chances are, you put a Module.php file at the module's root, and it either contains a Blog\Module class, or requires a classfile from your source tree that will. Let's setup autoloading:

$ composer require --dev zfcampus/zf-composer-autoloading
$ ./vendor/bin/autoload-module-via-composer Blog

Done.

The package ships with only a vendor binary, and that does the following:

• Adds an entry in your composer.json to autoload the module.
• Regenerates the Composer autoloading rules.

It will autodetect the module type (PSR-0 or PSR-4) based on the detected directory structure, but also allows you to specify the type via a CLI flag. You can also tell it where your Composer binary is, if it's not on your path.

Once you're done, if you defined a getAutoloaderConfig() method in your module, you can now remove it, as it's redundant!

This tool will work with existing ZF2 and Apigility installs, of any version.

Composer all the things!

Using Composer to Autoload ZF Modules was originally published 17 August 2016 on https://mwop.net by Matthew Weier O'Phinney.