Isapi.py

# Copyright 2010 Daniel Snider <qtipkk@gmail.com>
#
"""Django and WSGI ISAPI request handler.

Make a new application pool for each project and have an IIS Application point to a directory
containing either a .wsgi file, or a django project with a settings.py
"""
import sys
from Http.WSGI import RunWSGI
from Http import Env
import os

from PyISAPIe import Write

def path_module(path):
    """Split a path into containing path and folder."""
    pth, module = os.path.split(path)
    if not module:
        return os.path.split(pth)
    else:
        return pth, module

def wsgi_app(root_dir):
    """Get the handler from a .wsgi file in the root_dir."""
    for path in os.listdir(root_dir):
        if path.endswith(".wsgi"):
            variables = {}
            execfile(os.path.join(root_dir, path), variables)
            if variables.get("application"):
                return variables["application"]
    raise Exception("Couldn't find a WSGI application")

def django_app(root_dir):
    """Get the handler from a django project file in the root_dir."""
    import django.core.handlers.wsgi
    return django.core.handlers.wsgi.WSGIHandler()

def get_wsgi_application(root_dir):
    """Get either a WSGI app or a Django app."""
    try:
        return wsgi_app(root_dir)
    except:
        from django.core.handlers.wsgi import WSGIHandler as DjangoHandler
        if os.path.exists(os.path.join(root_dir, "settings.py")):
            path, module = path_module(Env.APPL_PHYSICAL_PATH)
            sys.path.append(path)
            os.environ["DJANGO_SETTINGS_MODULE"] = module+'.settings'
            return django_app(root_dir)
        else:
            raise Exception("Couldn't find a WSGI application or Django application")


handler = None
# PyISAPIe request
def Request():
    global handler
    if not handler:
        handler = get_wsgi_application(Env.APPL_PHYSICAL_PATH)
    s = Env.APPL_MD_PATH.split('/')
    base = '/'+'/'.join(s[s.index('ROOT')+1:])
    return RunWSGI(handler, Base=base)