Installing Composer on Mac OSX

Composer is a cross-platform dependency manager for PHP libraries.

In this guide, i'm installing Composer on a machine running Mac OSX with MAMP.

1. Open a terminal and navigate to your user directory, ie cd /User/<USER_NAME>/
2. Run this command shown below to download Composer. This will create a Phar (PHP Archive) file called composer.phar:

   curl -sS https://getcomposer.org/installer | php
   

3. Now we move composer.phar file to a directory

   sudo mv composer.phar /usr/local/bin/

4. We want to run Composer with having to be root al the time, so we need to change the permissions:

   sudo chmod 755 /usr/local/bin/composer.phar
   

    

5. Next, we need to let Bash know where to execute Composer: 

   nano ~/.bash_profile
   

   Add this line below to bash_profile and save
    

   alias composer="php /usr/local/bin/composer.phar"
   

   and then run this command:
    

   source ~/.bash_profile

    

6. Finally, run: 

   composer -v
   

   If all goes well and it is working, you'll see this screen:
   

Updated this post on 7 Dec 2020

Composer version 2 has been released for a few months now. Since i upgraded Drupal 9 to 9.1, it recommends to use Composer 2. So i thought it might as well be time to upgrade. The benefits it brings is that it is supposed to be much faster. 

If you have already installed Composer 1 and feel it is time to upgrade, the process is really simple. First, update to latest version. Type and run:

composer self-update

If you run composer self-update again, you will see this message:

 To upgrade to Composer 2.x from older version, type and run:

composer self-update --2

While using Composer 2.x and you are experiencing some issues using it with your project, you can always downgrade back to 1.x version. To do this, type and run:

composer self-update --rollback

Note: When you try to upgrade Drupal 9 with composer 2. You will get this error:

Problem 1

    - oomphinc/composer-installers-extender[v1.1, ..., v1.1.2] require composer-plugin-api ^1.0 -> found composer-plugin-api[2.0.0] but it does not match the constraint.

    - Root composer.json requires oomphinc/composer-installers-extender ^1.1 -> satisfiable by oomphinc/composer-installers-extender[v1.1, v1.1.1, v1.1.2].

What you will need to do first is to update the plugin (composer installer extender). To do this, open your your composer.json file and change this line to use ^2.0 version:

"oomphinc/composer-installers-extender": "^2.0"

 

Now you can try and run:

composer update