Composer Commands Documentation

Composer is a dependency manager for PHP that allows you to declare and manage the libraries your project depends on. This document outlines common Composer commands and their usage scenarios.

Installation Commands

Basic Installation

composer install

Use this command when:

• Setting up a project for the first time
• After cloning a repository
• When the vendor directory is missing
• When encountering 500 Internal Server Error due to missing packages

This command reads the composer.json and composer.lock files and installs all dependencies as specified in the lock file.

Production Installation

composer install --no-dev --optimize-autoloader

Use this command in production environments to:

• Install only production dependencies (skips development dependencies)
• Generate an optimized autoloader for better performance

Update Commands

Update All Packages

composer update

Use this command when:

• You want to update all dependencies to their latest versions according to the version constraints in composer.json
• After adding new modules programmatically or through a web interface
• After manually uploading packages that need to be recognized by the system

Update Specific Package

composer update vendor/package

Use this command to update a specific package while keeping all other dependencies at their current versions.

Autoloader Commands

Basic Autoloader Regeneration

composer dump-autoload

Use this command when:

• You encounter 500 Internal Server Error due to autoloading issues
• After adding new classes that need to be autoloaded
• After making changes to the PSR-4 or classmap autoloading in your project

Optimized Autoloader Regeneration

composer dump-autoload --optimize

Use this command in production environments to:

• Generate a more efficient autoloader by converting PSR-0/PSR-4 autoloading to classmap
• Improve application performance by reducing file lookups

Troubleshooting

If you encounter a 500 Internal Server Error or your site crashes, follow these steps:

1. Check if the vendor directory exists in your project root
2. If the vendor directory is missing, run composer install
3. If the vendor directory exists but issues persist, run composer dump-autoload
4. For production environments, use the optimized versions of commands:
   • composer install --no-dev --optimize-autoloader
   • composer dump-autoload --optimize

Best Practices

• Always commit your composer.json and composer.lock files to version control
• Do not commit the vendor directory to version control
• Use composer install when deploying to ensure consistency across environments
• Use composer update sparingly and with caution in production environments
• Run composer dump-autoload --optimize after deployment to production for better performance