以某种方式安装composer，以便其他用户也可以使用其全局供应商目录，缓存等

Question

Being a "root" user I install my composer like curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin -- --filename=composer which by default creates vendor-dir, cache etc inside /root/.composer. I want to install some global packages as root and let other users to use those packages. E.g

> whoami 
root
> composer global require hirak/prestissimo  (It makes packages download in parallel)
> su www-data
> cd /var/www/drupal
> composer install

Expected behaviour: It should download packages in parallel as install hirak/prestissimo globally but it does not. Because when I had installed that package it was inside /root/.composer/vendor and after switching to www-data it is not able to read/write /root/.composer/vendor

Answer 1

I would use bind mount, here is a post on stack exchange that covers it in far more detail then I can:

https://unix.stackexchange.com/questions/198590/what-is-a-bind-mount

I used it before to get out of CHROOT restrictions, for example C-Panel users are restricted to /home/user so they can't access anything above that. With bind mount, you can link a folder from above that to a folder in their Jail.