Re: Purpose of config.ru (regarding server options), #245

[coolesting <coolesting@gmail.com>]

I think the config.ru is a interface for rack and let the rack to do
something what we want .

Whatever we do anything with the config.ru, we need to based on the
rack interface provided,  that is why we create a file config.ru for
rackup to start up the variety of web server, just my opinion.

2011/10/2 Matthias Wächter <matthias@waechter.wiz.at>:
> Hi,
>
> Recently, I forked rack and created a feature
> [https://github.com/rack/rack/pull/245] that allows one to specify web
> server options as commands within config.ru, not only on the rackup command
> line or the comment line (#\) within config.ru. The need for this arises
> from new web server technologies like the ones typically used for Mongrel2
> which need significantly more setup information than a simple Webrick or
> (legacy) Mongrel server.
>
> Mongrel2 typically exchanges its web server requests and responses through
> *two* sockets, based on ZeroMQ, and these sockets can finally be Unix Domain
> Sockets which don’t waste the TCP socket address space. OTOH, in
> well-structured environments those IPC sockets need longer path names than a
> simple TCP port number, additionally it might be beneficial to use Ruby
> techniques to build up the IN and OUT IPC sockets based on some common
> pattern. Furthermore, Mongrel2 relies on a uuid setting for identifying
> sessions.
>
> Setting all those options on the command line to a standalone rackup
> execution defeats its purpose, and setting them within the config.ru file
> inside the tiny littly comment line is ugly and cannot make use of Ruby
> constructs at all. So the idea was to let the newly created Rack::Builder
> object handle those options and hand it over to the calling process.
>
> My change request, together with the necessary code and test changes, was
> rejected and closed right away by James with the comment
>
>> config.ru is supposed to be portable and not bound to a particular server.
>
> I wonder whether it’s James who doesn’t understand what I want, or whether
> it’s me who doesn’t understand what config.ru is supposed to be. I thought
> it is meant as a server configuration file: It
>
> • defines which server technology to use (if there are multiple to choose
> from or if I want a specific solution),
> • configures the used server, and
> • defines which application and possible middleware to load.
>
> The goal, as far as I got it, is to have the application and its setup bound
> together in a single configuration file, called config.ru. Sadly, the
> current syntax is only optimized for defining the application; the first two
> items on the list are handled via a clumsy comment line that gets longer the
> more options the web server requires for configuration.
>
> So, can someone enlighten me, what’s the purpose of config.ru? Isn’t it
> supposed to carry the configuration for the web server as well?  Is it a bad
> idea to let Rack::Builder collect all these options within the config.ru
> body instead of the comment line?
>
> – Matthias
>