On Wed, Mar 4, 2009 at 12:40 AM, Grzegorz Nosek <grze...@gmail.com>wrote:

I'm not a huge XMLRPC fan either but Python makes it easy for the project implementers. I suppose some other data format such as JSON is possible if there's a will.

I think it's difficult to kill individual processes that have timed out when a pool of processes are all listening on the same FCGI socket because nginx would not know which process had accepted the request that timed out (unless there is some mechanism in the FCGI protocol to do this). However, the entire process pool could be killed/restarted if that's the behavior you desire.

This is already available in supervisord

Functionality was recently added to supervisord to modify it's configuration dynamically through the XML-RPC api so this is matter of implementing the load logic in an nginx plugin and making calls to supervisord to add and subtract from the pool.

Depends on what kind of failure. If process foo exits with an unexpected exit code, supervisord has an event listening API (a simple text protocol listening on a pipe) that allows you to write an event handler in any language to deal with those events. However, if process foo fails in the sense of returning a 500 status code or not returning any data at all, that would have to be handled by nginx module.

I think the config is pretty simple but I'll let you be the judge ( http://supervisord.org/manual/current/configuration.html). I generate supervisord configs dynamically in my current company using Perl Template Toolkit.