Composer shim from docker container

composer.sh

#!/usr/bin/env bash

COMPOSER_IMAGE=composer

if [ -t 1 ] ; then
    mkdir -p "$HOME/.cache/composer"
    docker run \
        -it \
        --rm \
        -u "$(id -u):$(id -g)" \
        --env SSH_AUTH_SOCK=/tmp/agent.sock \
        --env COMPOSER_HOME=/composer \
        -v /etc/passwd:/etc/passwd:ro \
        -v /etc/group:/etc/group:ro \
        -v "$SSH_AUTH_SOCK":/tmp/agent.sock \
        -v "$HOME/.ssh/known_hosts":"$HOME/.ssh/known_hosts":ro \
        -v "$HOME/.cache/composer":/composer \
        -v "$(pwd)":/app \
        $COMPOSER_IMAGE "$@"
else
    docker run \
        -i \
        --rm \
        -u "$(id -u):$(id -g)" \
        --env COMPOSER_HOME=/composer \
        -v /etc/passwd:/etc/passwd:ro \
        -v /etc/group:/etc/group:ro \
        -v "$HOME/.ssh":"$HOME/.ssh":ro \
        -v /var/lib/composer:/composer \
        -v "$(pwd)":/app \
        $COMPOSER_IMAGE "$@"
fi