= CookBook - IP Access Middleware =

== The idea ==

Controling IP access in your web app. The idea provided in this cookbook let you define specific ip addresses, and controlling accessing from those ips. If an user access from a certain IP, automatically authenticates with a defined user.

== IPAccess Model ==

You must define a model that permits defining a tuple (ip addr, user): ip from browser that connect, and users that authenticated.

This is the model proposed (it would be in a file like ''myproj/myapp/models.py''):

{{{

from django.contrib.auth.models import User

class IPAccess(models.Model):
    ip = models.IPAddressField(unique=True, db_index=True)
    user = models.ForeignKey(User, verbose_name='user that authenticates')

    def __str__(self):
        return self.ip

    class Meta:
        verbose_name = 'IP Access'
        verbose_name_plural = 'IP Accesses'

    class Admin:
        list_display = ('ip', 'user')

}}} 


== IPAccess Middleware ==

Middleware mission is authenticate automatically with an user defined in models, '''only if''' the browser remote ip address exists in ''IPAccess'' table. 

This is the code (in file ''myproj/myapp/middleware.py''):

{{{

from django.contrib.auth.models import AnonymousUser
from myproj.myapp.models import IPAccess

class IPAccessMiddleware(object):
    def process_request(self, request):
        if request.user == AnonymousUser():
            remoteip = request.META['REMOTE_ADDR']
            try:
                ipaccess = IPAccess.objects.get(ip=remoteip)
                request.user = ipaccess.user
            except IPAccess.DoesNotExist:
                pass
        return None

}}}

== Settings ==

The middleware installation requires you insert ''IPAccessMiddleware'' into ''MIDDLEWARE_CLASSES''. Obviusly, it also requires the installation of ''!AuthenticationMiddleware''.

The code would be like that:

{{{

MIDDLEWARE_CLASSES = (
    'django.middleware.common.CommonMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.middleware.doc.XViewMiddleware',
    'aceprensa.apps.news.middleware.IPAccessMiddleware',
)

}}}

== Complete Application ==

I also developed [attachment:ipaccess.tgz ipaccess application] which offers this functionality. For installing you have to untar compressed application and put in ''apps'' directory in your project. Then, you have to ''update'' import statements and add to applications installed settings:

{{{

INSTALLED_APPS = (
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.sites',
    'django.contrib.comments',
    'django.contrib.admin',
    'yourproject.apps.yourapp',
    'yourproject.apps.ipaccess',
)

}}}