nginx-php-fpm/docs/php_modules.md

Install PHP Modules

To install and configure extra PHP modules in this image, first of all drop into the container:

docker exec -t -i nginx /bin/bash

Then configure and install your module:

/usr/local/bin/docker-php-ext-configure sockets
/usr/local/bin/docker-php-ext-install sockets

Now restart php-fpm:

supervisorctl restart php-fpm

We may include a env var to do this in the future.