How to Install and Use Composer on Ubuntu 22.04: Step-by-Step Guide

To install and use Composer on Ubuntu 22.04, follow these detailed steps:

Step 1: Update Your System

Before installing Composer, update your package list to ensure that you have the latest versions of all your packages.

sudo apt update
sudo apt upgrade -y

Step 2: Install PHP and Dependencies

Composer requires PHP to run. Install PHP along with other necessary dependencies.

sudo apt install php-cli unzip curl -y

Step 3: Download Composer Installer

Use curl to download the Composer installer.

curl -sS https://getcomposer.org/installer -o composer-setup.php

Step 4: Verify the Installer (Optional but Recommended)

Before running the installer, it’s recommended to verify the installer’s integrity to make sure it’s secure.

1. Get the latest installer signature:

   HASH="$(curl -sS https://composer.github.io/installer.sig)"

2. Verify the installer:
   php -r "if (hash_file('SHA384', 'composer-setup.php') === '$HASH') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"

If the output says Installer verified, you can proceed to the next step. If it says Installer corrupt, don’t continue, and download the installer again.

Step 5: Install Composer

Run the installer to install Composer globally on your system:

sudo php composer-setup.php --install-dir=/usr/local/bin --filename=composer

This will move Composer to /usr/local/bin so that it can be accessed globally using the composer command.

Step 6: Clean Up

Remove the composer-setup.php file, as it’s no longer needed.

rm composer-setup.php

Check if Composer has been installed successfully by running:

composer --version

This should output the version of Composer that you installed, such as:

Composer version 2.x.x 2024-xx-xx

Step 8: Using Composer

Now that Composer is installed, you can use it to manage PHP project dependencies. Here are some basic Composer commands:

1. Install Dependencies (for an existing project)
   Run this in your project directory where the composer.json file is located:

   composer install

2. Create a New Project
   You can create a new Laravel project, for example:

   composer create-project --prefer-dist laravel/laravel my-laravel-app

3. Add a Package to Your Project
   To add a new package to your project, use:

   composer require vendor/package

4. Update Dependencies
   To update all the dependencies listed in your composer.json file:

   composer update

5. Check Installed Packages
   To list all installed packages:

   composer show

Composer is now installed and ready to use on your Ubuntu 22.04 system!

Let me know if you need help with anything else related to Composer.