Warn if both WORDPRESS_DB_HOST and MYSQL_PORT_3306_TCP are set

[md5]

No description provided.

[mrjackdavis]

LGTM, I feel this is getting a bit messy though

[md5]

I'm curious how you think it's getting messy.

The only messy part in my opinion is that some people had been relying on the undocumented ability to set MYSQL_PORT_3306_TCP to configure an external database for this image. Since that ability was not a supported feature, I think @tianon's change in 9aae243 was reasonable.

Now that the ability to configure an external db directly with WORDPRESS_DB_HOST has been added, the situation seems pretty clean to me:

• If you want a linked database, use --link mysql and the mysql entry in /etc/hosts with be used as DB_HOST in wp-config.php
• If you want to use an external database, set WORDPRESS_DB_HOST and that value will be used directly for DB_HOST in wp-config.php

Once this PR is merged (or something like it), the user will be warned if they try to use both -e WORDPRESS_DB_HOST=... and --link some-mysql:mysql. If someone had been using MYSQL_PORT_3306_TCP directly and are now wondering why Wordpress isn't trying to connect to their external db, at least those people will also get an error message now.

[mrjackdavis]

Sorry @md5, I should've provided a bit more detail.

The reason I feel it's getting messy (100% subjective), is that a good amount of fringe case checks are entering the docker-entrypoint.sh; making it a little hard to read. It's fine for now. But IMHO if we continue on the current track it'll get a little unmanageable.

Otherwise, the fix is great. Thanks for doing that

[tianon]

LGTM

[tianon]

cc @yosifkit

[yosifkit]

LGTM