Mongo aggregation doesn't work in pymongo - django

Question

I am trying to make a query with aggregate in Django, it works fine with my local computer but not in the server.
In both machines, pymongo is installed in Python virtual enviroment:
pip freeze | grep mongo
pymongo==2.5.2
I can also get the inserted data in two machines with find() method:
conn.firmalar.searchlogger.find()
But aggregate method works in my local but not in the server even everything installed are the same. I got this error when i attempt to run it on server:
import pymongo
conn = pymongo.Connection()
search = conn.firmalar.searchlogger.aggregate([{"$group": {"_id": "$what", "count": {"$sum": 1}}}])
OperationFailure at /admin/weblog/
command SON([('aggregate', u'searchlogger'), ('pipeline', [{'$group': {'count': {'$sum': 1}, '_id': '$what'}}])]) failed: no such cmd: aggregate
/home/cem/env/firmalar/local/lib/python2.7/site-packages/pymongo/collection.pyc in aggregate(self, pipeline)
1059 self.secondary_acceptable_latency_ms),
1060 slave_okay=self.slave_okay,
-> 1061 _use_master=use_master)
1062
1063 # TODO key and condition ought to be optional, but deprecation
/home/cem/env/firmalar/local/lib/python2.7/site-packages/pymongo/helpers.pyc in _check_command_response(response, reset, msg, allowable_errors)
145 if code in (11000, 11001, 12582):
146 raise DuplicateKeyError(errmsg, code)
--> 147 raise OperationFailure(msg % errmsg, code)
148
149

Answer 1

It's not about the driver - it's about mongodb itself. aggregate() was introduced in mongodb 2.2: docs.
Most likely, you are using an older version of mongodb. Check your mongodb version and upgrade if needed. Also check that in your python code you are connecting to the mongodb version >=2.2.
Also see:
MongoDB Java driver : no such cmd: aggregate
Aggregate failed: no such cmd: aggregate