Hi Graham, Thanks so much for all that information, it is greatly appreciated.
Kind regards, Sarah vardy ----- Original Message ----- From: Graham Dumpleton <[EMAIL PROTECTED]> Date: Tuesday, April 1, 2008 1:54 pm Subject: Re: Dynamic Subdomain Generation for Users To: Django users <django-users@googlegroups.com> > > > > On Apr 1, 1:21 pm, [EMAIL PROTECTED] wrote: > > Hey, > > > > I am currently looking at installing multiple instances of > Django on a server to use Django as a teaching and learning tool. > > > > What is the best way to go about this? > > > > I want to minimise the amount of storage needed and optimize > the performance of the server. > > I wouldn't get too worried about performance, at least not > speed. You > would probably find Django's internal development web server > more than > adequate in a teaching environment and certainly would make restarts > when code changes easier to manage. > > The only time internal server may be a problem is if writing complex > AJAX applications that expect to be able to have multiple concurrent > requests handled while prior requests haven't been completed. This > would be an issue because internal server is single threaded and > wouldn't allow concurrent requests which overlap in time. In other > words, all requests are serialised. > > Only other real issue is the amount of memory used and as long > as you > stick with Django development server, or use a hosting mechanism which > uses a single multithreaded process or non threaded this > shouldn't be > a problem either. Use a multithreaded process though and you > have to > start introducing students to issues of thread safety in programming. > > People who do have problems with too much memory being used are often > trying to run Django embedded inside of Apache prefork processes > on a > memory constrained VPS. In other words, you just need to pick the > right hosting technology. You also need to consider whether in the > time of the course whether students would develop enough stuff > that it > would start consuming huge amounts of memory. > > > I have heard that modwsgi can be used to specify different > ports for each instance. > > Technically, no it doesn't. There seems to be growing misunderstanding > in some quarters about how mod_wsgi works and this is one of the > misconceptions. The other main misconceptions are that mod_wsgi > implements some sort of wire protocol called WSGI and that the > 'python' executable is actually launched as a separate process > to run > the application. Neither of these is correct either. > > What mod_wsgi does is implement the WSGI functional API specification. > This is to do with what happens within a Python process and how > a web > server layer talks to a higher application layer. It has got nothing > to do with socket communications, its is a programmatic interface > only. > > That all said, mod_wsgi does conceptually allow what you want in as > much as it does allow instances of applications to be run in separate > processes if you enable that feature. Those processes are though a > direct fork of the Apache parent process. Communications between these > processes and main Apache child processes is handled by UNIX sockets, > but that is actually totally irrelevant as the socket isn't the > defined public interface as it is with something like FASTCGI. Even > when run in the separate process the interface is still the > programmatic WSGI interface, mod_wsgi just handles it all > transparently and makes it work. > > > I was a little concerned about using the same db for all the > students, as if they make a bogus > query, update or insert on the db the whole db could be altered > unfavourably. > > Again because I don't believe that performance should be your priority > in your setup, just use separate sqlite data for each user. This has > the benefit as well that you don't need to set up and manage a full > blown database system. > > > Could the script used in this post be used to create > subdomains for the users? Has this script has been written for > just one instance of django? > > If you set up each user with their own Django instance this > would be > required in the first place. > > > Is the easiest way going to be to create a directory for each > user where a new instance of django is installed? > > Pretty well. You just need to allocate them a separate listener socket > port number for them to use so they don't tread on each other though. > > Anyway, all probably depends on how simple you want to keep it. > :-) > > Graham > > > Any help or advice would be greatly appreciated. > > > > Thanks, > > > > Sarah > > > > > > > > ----- Original Message ----- > > From: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]> > > Date: Tuesday, April 1, 2008 12:31 pm > > Subject: Re: Dynamic Subdomain Generation for Users > > To: Django users <django-users@googlegroups.com> > > > > > Thanks, Dan! > > > > > Just what I needed. > > > > > On Mar 31, 5:58 pm, Dan Ellis <[EMAIL PROTECTED]> wrote: > > > > Hi, Levi. I've just had a look through the code, and it > > > appears you're > > > > in luck (at least in the trunk -- I haven't looked > elsewhere). core/ > > > > handlers/base.py contains this line[1]: > > > > > > # Get urlconf from request object, > if available. > > > Otherwise use > > > > default > > > > urlconf = getattr(request, > "urlconf", settings.ROOT_URLCONF) > > > > > > It would appear that if the request contains an attribute called > > > > 'urlconf', that will be used instead of the default urls.py. > > > So all > > > > you need is a request middleware[2] that examines > > > > request.META["HTTP_HOST"] and sets the appropriate urlconf. > > > > > > Bah. On closer inspection of the docs, it appears this is > already> > > documented[3]. Still, it was a satisfying search ;-) > > > > > > Hope this helps, > > > > Dan > > > > > > [1]http://code.djangoproject.com/browser/django/trunk/django/core/handle...> > [2]http://www.djangoproject.com/documentation/middleware/#process-request > > > > > > [3]http://www.djangoproject.com/documentation/url_dispatch/#how-django-p... > > > > Sarah Vardy > > Research Computing Services > > Griffith University, Nathan QLD > > 0402241794 > > > Sarah Vardy Research Computing Services Griffith University, Nathan QLD 0402241794 --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
