Multiple permanent connection for Django?

My website is using Django, and now I want to port part of the logic to a Redi开发者_如何学Cs, so I need a Redis connection for my views.py code, obvious I can't write connect to redis code in views.py because it might be called multiple times, so I need to put the connect somewhere in the django, perhaps middleware?

But I don't want to make this complicated, just the same place where the MySQL database connected, I want to add a global object for Redis connection. Perhaps later for XMPP conenction and ZeroMQ.

How to do this?

ANy idea is appreciated. Thanks in advance :)

in typical Django server settings multiple requests will be handled by the same worker process.

You can simply put a global variable to hold the connection on top of views.py and use the conenction in each view function/class, the connection will be established when the worker process starts and closes when the worker process got recycled. It's semi-permanent connection but good enough.

MySQL connection works the same way in Django. It's not each db connection per request but per worker process life-span

It isn't obvious you want to do that. It isn't obvious why you would want to do that.

So why not connect in views.py? To use a single "global connection" will mean adding locking/serialization code to ensure that your connection is safe to use amongst many calls to your views. I actually create and connect right in the method in my various and sundry views.py files. Sometimes I connect to one instance or another. I've seen no performance issues and also don't have to worry about concurrency safety. I let Redis figure that out.

Another aspect of a global shared connection is degraded performance - you'll have one page view waiting on another's to finish before it can run. By allowing each to have it's own connection you avoid one view slowing down another while waiting on access to a global connector.

Consider this: if your queries are so small and fast that you don't expect to see a performance hit from serializing every page that accesses Redis, then you won't see any performance degradation from a connection per page as you connect, query, and close. I highly doubt that the cost of setting up the connection is significantly more than serializing all page accesses that connect to Redis.

So my suggestion is to just try it. If and only if you see an issue should you worry about implementing something you will probably not need.

There is a great piece of code for this already. http://github.com/andymccurdy/redis-py