composer/doc/articles/scripts.md

Scripts

What is a script?

A script, in Composer's terms, can either be a PHP callback (defined as a static method) or any command-line executable command. Scripts are useful for executing a package's custom code or package-specific commands during the Composer execution process.

Note: Only scripts defined in the root package's composer.json are executed. If a dependency of the root package specifies its own scripts, Composer does not execute those additional scripts.

Event names

Composer fires the following named events during its execution process:

Command Events

• pre-install-cmd: occurs before the install command is executed.
• post-install-cmd: occurs after the install command is executed.
• pre-update-cmd: occurs before the update command is executed.
• post-update-cmd: occurs after the update command is executed.
• pre-status-cmd: occurs before the status command is executed.
• post-status-cmd: occurs after the status command is executed.
• pre-archive-cmd: occurs before the archive command is executed.
• post-archive-cmd: occurs after the archive command is executed.
• pre-autoload-dump: occurs before the autoloader is dumped, either during install/update, or via the dump-autoload command.
• post-autoload-dump: occurs after the autoloader is dumped, either during install/update, or via the dump-autoload command.
• post-root-package-install: occurs after the root package has been installed, during the create-project command.
• post-create-project-cmd: occurs after the create-project command is executed.

Installer Events

• pre-dependencies-solving: occurs before the dependencies are resolved.
• post-dependencies-solving: occurs after the dependencies are resolved.

Package Events

• pre-package-install: occurs before a package is installed.
• post-package-install: occurs after a package is installed.
• pre-package-update: occurs before a package is updated.
• post-package-update: occurs after a package is updated.
• pre-package-uninstall: occurs before a package has been uninstalled.
• post-package-uninstall: occurs after a package has been uninstalled.

Plugin Events

• command: occurs before any Composer Command is executed on the CLI. It provides you with access to the input and output objects of the program.
• pre-file-download: occurs before files are downloaded and allows you to manipulate the RemoteFilesystem object prior to downloading files based on the URL to be downloaded.

Note: Composer makes no assumptions about the state of your dependencies prior to install or update. Therefore, you should not specify scripts that require Composer-managed dependencies in the pre-update-cmd or pre-install-cmd event hooks. If you need to execute scripts prior to install or update please make sure they are self-contained within your root package.

Defining scripts

The root JSON object in composer.json should have a property called "scripts", which contains pairs of named events and each event's corresponding scripts. An event's scripts can be defined as either as a string (only for a single script) or an array (for single or multiple scripts.)

For any given event:

• Scripts execute in the order defined when their corresponding event is fired.
• An array of scripts wired to a single event can contain both PHP callbacks and command-line executable commands.
• PHP classes containing defined callbacks must be autoloadable via Composer's autoload functionality.
• If a defined callback relies on functions defined outside of a class, the callback must explicitly require the composer autoloader. If used in a context wherevendor/autoload.php might not yet exist (such as during a pre-install or pre-update command), the callback should explicitly require whatever files within your root package it needs to execute successfully.

Script definition example:

{
    "scripts": {
        "post-update-cmd": "MyVendor\\MyClass::postUpdate",
        "post-package-install": [
            "MyVendor\\MyClass::postPackageInstall"
        ],
        "post-install-cmd": [
            "MyVendor\\MyClass::warmCache",
            "phpunit -c app/"
        ],
        "post-create-project-cmd" : [
            "php -r \"copy('config/local-example.php', 'config/local.php');\""
        ]
    }
}

Using the previous definition example, here's the class MyVendor\MyClass that might be used to execute the PHP callbacks:

<?php

namespace MyVendor;

use Composer\Script\Event;
use Composer\Installer\PackageEvent;

class MyClass
{
    public static function postUpdate(Event $event)
    {
        $composer = $event->getComposer();
        // do stuff
    }
    
    public static function postAutoloadDump(Event $event)
    {
        $vendorDir = $event->getComposer()->getConfig()->get('vendor-dir');
        require "$vendorDir/autoload.php";
        
        some_function_from_an_autoloaded_file();
    }

    public static function postPackageInstall(PackageEvent $event)
    {
        $installedPackage = $event->getOperation()->getPackage();
        // do stuff
    }

    public static function warmCache(Event $event)
    {
        // make cache toasty
    }
}

When an event is fired, your PHP callback receives as first argument an Composer\EventDispatcher\Event object. This object has a getName() method that lets you retrieve event name.

Depending on the script types (see list above) you will get various event subclasses containing various getters with relevant data and associated objects:

• Base class: Composer\EventDispatcher\Event
• Command Events: Composer\Script\Event
• Installer Events: Composer\Installer\InstallerEvent
• Package Events: Composer\Installer\PackageEvent
• Plugin Events:
  • command: Composer\Plugin\CommandEvent
  • pre-file-download: Composer\Plugin\PreFileDownloadEvent

Running scripts manually

If you would like to run the scripts for an event manually, the syntax is:

composer run-script [--dev] [--no-dev] script

For example composer run-script post-install-cmd will run any post-install-cmd scripts that have been defined.

You can also give additional arguments to the script handler by appending -- followed by the handler arguments. e.g. composer run-script post-install-cmd -- --check will pass--check along to the script handler. Those arguments are received as CLI arg by CLI handlers, and can be retrieved as an array via $event->getArguments() by PHP handlers.

Writing custom commands

If you add custom scripts that do not fit one of the predefined event name above, you can either run them with run-script or also run them as native Composer commands. For example the handler defined below is executable by simply running composer test:

{
    "scripts": {
        "test": "phpunit"
    }
}

Note: Composer's bin-dir is pushed on top of the PATH so that binaries of dependencies are easily accessible as CLI commands when writing scripts.