[Web-SIG] Re: Preferred set of WSGI servers

[Ian Bicking]

Peter Hunt wrote:
> Actually, I think a mod_wsgi for Apache and IIS would be one of _the_ 
> most important things for WSGI. I think that it would search for a 
> __wsgi__.py file (or maybe something with a better name) which would 
> expose a WSGI application named "application" that would handle requests 
> for the directory in which it exists. This would allow a user to simply 
> drop a file on the webserver and have it work. It would be excellent for 
> shared hosting solutions.

Would it?  From what I can tell, mod_php is very popular in shared 
hosts, but neither mod_python nor mod_perl are.  I don't think mod_* 
makes it necessarily host-friendly.  But from what I can tell of 
mod_python, it would be relatively easy to have something like .wsgi 
files, and give them a handler that runs them as WSGI apps.

I can imagine a good setup for hosts being one based on forking per-user 
processes, which is adaptive primarily to scale down -- e.g., a largely 
dorman app could have 1 or even 0 processes running (at 0 it becomes 
similar to CGI, but presumably the process would stay around for some 
time to respond to subsequent requests).  The "scaling down" scenario I 
often think about would be a email contact form -- one of those things 
that has to be an app, can be implemented and deployed separately from 
other aspects of the site, and yet it's clear waste of resources to keep 
a process always around to respond to such requests.  Though it's 
actually someplace where CGI would work just fine; but lets say you 
don't want to educate the developer about when they might want to use 
other deployment strategies (which is a rather complex discussion 
really, that would be better avoided by providing one really good 
strategy and telling everyone to use it).

Maybe mod_python is appropriate for that kind of situation, I'm not 
sure.  It could also be implemented with a second, single process that 
was developed and deployed separately from Apache.

As for IIS and ISAPI, I can't say I really know what the archicture of 
that system is, so I don't know.  Oh, but that does remind me of another 
WSGI server: ASP.  Though I remember vaguely this came up before and it 
seemed infeasible because ASP didn't support anything like PATH_INFO. 
Oh well, I can't remember now.

-- 
Ian Bicking  /  ianb at colorstudy.com  /  http://blog.ianbicking.org