如何使用docker exec安装Composer

Question

I'm trying to install composer on docker container. I have a container laravel55 and I'm gonna to install composer insite it.

docker exec laravel55 curl --silent --show-error 
https://getcomposer.org/installer | php

#result
Composer (version 1.6.5) successfully installed to: /root/docker- 
images/docker-php7-apache2/composer.phar
Use it: php composer.phar

Aftar installation, I'm trying to using composer but it doesn't work:

 docker exec -w /var/www/html laravel55 php composer.phar install

#result
Could not open input file: composer.phar

It seems that Composer had not installed! How can I install composer on a docker container?

Answer 1

Well with your command you're actually installing composer.phar locally on your host, you just execute the curl command inside the container. The part behind the pipe symbol | is not executed in your docker container but on your host. In your second command you switch your working directory to /var/www/html where you apparently expect the composer.phar but not in the first command.

So to make the whole command run in the container, you can try the following:

docker-compose exec -w /var/www/html laravel55 \
    sh -c "curl --silent --show-error https://getcomposer.org/installer | php"

Answer 2

You could use official composer image from dockerhub and mount on it a volume from your app container

ie

docker run -td --name my_app --volume /var/www myprivateregistry/myapp

docker run --rm --interactive --volumes-from my_app --volume /tmp:/tmp --workdir /var/www  composer install