How to install composer in Ubuntu

About Composer

Composer is a popular dependency management tool for PHP, created mainly to facilitate installation and updates for project dependencies. It will check which other packages a specific project depends on and install them for you, using the appropriate versions according to the project requirements.

Requirments

Before install composer we need PHP. If you do not install PHP then first you need to install PHP in your ubuntu system.

If you need help to install PHP then click here for more info.

After installing PHP we can able to install composer in Ubuntu.

Installing Composer

Composer provides an installer script written in PHP. We’ll download it, verify that it’s not corrupted, and then use it to install Composer.

Make sure you’re in your home directory, then retrieve the installer using curl:

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

Next, we’ll verify that the downloaded installer matches the SHA-384 hash for the latest installer found on the Composer Public Keys / Signatures page. To facilitate the verification step, you can use the following command to programmatically obtain the latest hash from the Composer page and store it in a shell variable:

HASH=`curl -sS https://composer.github.io/installer.sig`

If you want to verify the obtained value, you can run:

echo $HASH

Output
e0012edf3e80b6978849f5eff0d4b4e4c79ff1609dd1e613307e16318854d24ae64f26d17af3ef0bf7cfb710ca74755a

Now execute the following PHP code, as provided in the Composer download page, to verify that the installation script is safe to run:

php -r "if (hash_file('SHA384', '/tmp/composer-setup.php') === '$HASH') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"

You’ll see the following output:

Output
Installer verified

If the output says Installer corrupt, you’ll need to download the installation script again and double check that you’re using the correct hash. Then, repeat the verification process. When you have a verified installer, you can continue.

To install composer globally, use the following command which will download and install Composer as a system-wide command named composer, under /usr/local/bin:

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

You’ll see output similar to this:

Output
All settings correct for using Composer
Downloading...

Composer (version 2.2.9) successfully installed to: /usr/local/bin/composer
Use it: php /usr/local/bin/composer

To test your installation, run this:

composer

Output
   ______
  / ____/___  ____ ___  ____  ____  ________  _____
 / /   / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___/
/ /___/ /_/ / / / / / / /_/ / /_/ (__  )  __/ /
\____/\____/_/ /_/ /_/ .___/\____/____/\___/_/
                    /_/
Composer version Composer version 2.2.9 2022-03-15 22:13:37
Usage:
  command [options] [arguments]

Options:
  -h, --help                     Display this help message
  -q, --quiet                    Do not output any message
  -V, --version                  Display this application version
      --ansi                     Force ANSI output
      --no-ansi                  Disable ANSI output
  -n, --no-interaction           Do not ask any interactive question
      --profile                  Display timing and memory usage information
      --no-plugins               Whether to disable plugins.
  -d, --working-dir=WORKING-DIR  If specified, use the given directory as working directory.
      --no-cache                 Prevent use of the cache
  -v|vv|vvv, --verbose           Increase the verbosity of messages: 1 for normal output, 2 for more verbose output and 3 for debug
...

That’s all for installing composer in Ubuntu.