I'm pleased to announce gevent-fastcgi library. It allows you to
deploy your WSGI application using FastCGI protocol. It is still in
Beta stage and I'll greatly appreciate bug reports and ideas on how it
could be improved.

What makes it special? Well, gevent means greenlet co-routines are
used in place of usual threads (no GIL brakes). FastCGI means you can
use UNIX-sockets instead of TCP for faster communication between Web-
server and WSGI application. There is forgotten treasure - FastCGI
connection multiplexing - when single connection between Web-server
and application is used for multiple simultaneous requests. All above
combined with "native" usage of gevent library (no monkey-patching) is
what I believe makes it unique.

Of course, like anything else, it is not a solution to any problem.
Your application must be "green" in order to work well with gevent-
fastcgi. For instance your application should use DBAPI that is
coroutine-friendly (see psycopg2.extensions.set_wait_callback). And
despite the fact it's been used for several month on low-load
production server it most likely has its bugs.

Lets see how you can deploy your Pylons/Pyramid application using
gevent-fastgi:

First, install gevent-fastcgi package:

$ pip install gevent-fastcgi

or

$ easy_install gevent-fastcgi

or

checkout from git repository at https://github.com/momyc/gevent-fastcgi.git

Once it's installed you have two more options to deploy your
application:

If you use PasteDeploy or pserve method:

[server:main]
use = gevent_fastcgi#fastcgi
host = 127.0.0.1
port = 5432
# socket can be used instead of host/port
# socket = /path/to/socket

# set maximum simultaneous connections allowed (don't forget to set
your OS limits accordingly)
# max_conns = 32768

# try to recv data in big chunks
# set it to expected request body size + 8 bytes of FastCGI header
# affects performance of requests that have content
# buffer_size = 4096

Instantiate WSGIServer and call its serve_forever method. The
following is modified version of simple Pyramid application as per
official Pyramid docs:

from gevent_fastcgi.server import WSGIServer
from pyramid.config import Configurator
from pyramid.response import Response

def hello_world(request):
   return Response('Hello %(name)s!' % request.matchdict)

if __name__ == '__main__':
   config = Configurator()
   config.add_route('hello', '/hello/{name}')
   config.add_view(hello_world, route_name='hello')
   app = config.make_wsgi_app()
   server = WSGIServer('0.0.0.0', 8080, app)
   server.serve_forever()

Any bug reports and ideas on how it could be improved/changed are
welcome.

--
Alex K