Essential Composer CLI Commands Cheat Sheet

#php #laravel #symfony

Composer is the dependency manager for PHP that helps you manage packages and libraries in your projects.

Below is a handy list of commonly used Composer CLI commands with one-line explanations to keep as a quick reference.

Installation and Updates

composer self-update → Updates Composer itself to the latest version.
composer diagnose → Checks your system for common issues with Composer setup.

Project Setup

composer init → Starts an interactive session to create a composer.json file.
composer create-project vendor/package [dir] → Creates a new project from a package (e.g., Laravel, Symfony).

Dependencies Management

composer install → Installs dependencies listed in composer.lock (or composer.json if no lock file exists).
composer update → Updates all dependencies to the latest versions according to composer.json.
composer require vendor/package → Installs and adds a package to your project.
composer remove vendor/package → Removes a package and updates composer.json.

Autoloading

composer dump-autoload → Regenerates the autoloader for faster class loading.
composer dump-autoload -o → Optimizes autoloader by converting PSR-0/4 autoloading rules into a class map.

Information & Debugging

composer show → Lists all installed packages in the current project.
composer show vendor/package → Shows detailed information about a specific package.
composer outdated → Displays packages that have updates available.
composer why vendor/package → Shows which package requires a given dependency.
composer why-not vendor/package → Explains why a package cannot be installed or updated.

Scripts & Custom Commands

composer run-script script-name → Runs a script defined in composer.json.
composer test → Shortcut to run the test script defined in your composer.json.
Global Usage
composer global require vendor/package → Installs a package globally (available system-wide).
composer global show → Lists globally installed Composer packages.

Cache & Config

composer clear-cache → Clears Composer’s cache.
composer config key value → Sets a configuration option (local or global).
composer config --list → Shows all current Composer configuration settings.

Version Control

composer install --no-dev → Installs only production dependencies.
composer install --dev → Installs development dependencies.
composer update --lock → Updates only the composer.lock file without changing dependencies.

Handy Flags