Composer install fails in a cluster environment if we have a database in a different host

Hi,

Having my eZ Publish installation in one machine (10.0.5.2) and my database in a different one (10.0.5.4), when doing the composer update i have the following error:

 [eZDBNoConnectionException]
  Unable to connect to the database server 'localhost'
  Error #2002: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

Steps to Reproduce

– Clone eZ Publish Platform or community
$ git clone git@github.com:ezsystems/ezpublish-platform.git ezpublish5
$ cd ezpublish5
– Change your ezpublish_setup.yml, updating the following settings:

doctrine:
    dbal:
        connections:
            default:
                driver: pdo_mysql
                host: 10.0.5.4
                user: ezp
                password: myPassword
                dbname: ezp

– execute the composer install
$ curl -sS https://getcomposer.org/installer | php
$ php composer.phar install --prefer-dist

The error appears during this last command.

Workaround:

What seems to be happening.
When executing the composer install, the ezpublish_legacy folder is fetched. There, we have the default settings in site.ini

[DatabaseSettings]
DatabaseImplementation=ezmysqli
Server=localhost
Port=
User=root
Password=
Database=nextgen

If we change these site.ini settings to

[DatabaseSettings]
DatabaseImplementation=ezmysqli
Server=10.0.5.4
Port=
User=ezp
Password=myPassword
Database=ezp

and re-execute the composer install
$ php composer.phar install --prefer-dist

then the installation seems to be restarted where is stopped last time, and we can finish the installation
But... it's not a nice thing to do.