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#

Installer Events#

Package Events#

Plugin Events#

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 a string (only for a single script) or an array (for single or multiple scripts.)

For any given event:

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-autoload-dump": [
            "MyVendor\\MyClass::postAutoloadDump"
        ],
        "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
    }
}

Note: During a composer install or update process, a variable named COMPOSER_DEV_MODE will be added to the environment. If the command was run with the --no-dev flag, this variable will be set to 0, otherwise it will be set to 1.

Event classes#

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

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

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: Before executing scripts, Composer's bin-dir is temporarily pushed on top of the PATH environment variable so that binaries of dependencies are easily accessible. In this example no matter if the phpunit binary is actually in vendor/bin/phpunit or bin/phpunit it will be found and executed.

Referencing scripts#

To enable script re-use and avoid duplicates, you can call a script from another one by prefixing the command name with @:

{
    "scripts": {
        "test": [
            "@clearCache",
            "phpunit"
        ],
        "clearCache": "rm -rf cache/*"
    }
}

Calling Composer commands#

To call Composer commands, you can use @composer which will automatically resolve to whatever composer.phar is currently being used:

{
    "scripts": {
        "test": [
            "@composer install",
            "phpunit"
        ]
    }
}

One limitation of this is that you can not call multiple composer commands in a row like @composer install && @composer foo. You must split them up in a JSON array of commands.

Executing PHP scripts#

To execute PHP scripts, you can use @php which will automatically resolve to whatever php process is currently being used:

{
    "scripts": {
        "test": [
            "@php script.php",
            "phpunit"
        ]
    }
}

One limitation of this is that you can not call multiple commands in a row like @php install && @php foo. You must split them up in a JSON array of commands.

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