Install composer latest version on Ubuntu 20.04

composer.sh

#!/usr/bin/env bash

set -e
set -x

# Update server
sudo apt update

# Install some needed packages
sudo apt install php-cli unzip

# Download and Install Composer
cd ~
curl -sS https://getcomposer.org/installer -o composer-setup.php

# Verify that the downloaded installer matches the SHA-384 hash
HASH=`curl -sS https://composer.github.io/installer.sig`

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

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