Using memcached from an Nginx module

[erankor2]

Hi All,

I want to develop an Nginx HTTP module that gets several values from
memcache, performs some processing on them and returns the result to the
client. I want all memcache operations to be performed asynchronously
without blocking the worker process for maximum scalability. For this
reason, I can't use libmemcached, and I'm looking for something that is
built on Nginx. 
Is anyone familiar with a piece of code that does that ?

Some more details:
As I understand, it is theoretically possible to use the existing memcache
upstream module for this, using subrequests. For example, to get a value I
could start a subrequest for it and then handle the result when the
subrequest completes. But this approach sounds a bit awkward, and it has the
unnecessary overhead of processing all these dummy HTTP requests.
What I would like ideally, is a module that exposes a function like -
memcache_get(keyname, callback, context), where the callback is called
either with the value if successful or an error code. I started writing such
a module using the http_upstream module as reference, but found that it
takes quite a bit of code to get it done, with lots of edge cases to handle
(like timeouts in each one of the states)

Thank you !

Eran

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,247481,247481#msg-247481