I would like to count matching records with pymongo. I have looked up the documentation: https://docs.mongodb.com/manual/reference/operator/aggregation/group/#group-by-month-day-and-year
I understand that I should do something like:
db.foo_baz.aggregate([{'$group': {'_id': '$baz_id', 'count': {'$sum': 1}}}])
However, I am getting this error:
File "/usr/lib/python3.6/site-packages/mongomock/collection.py", line 1531, in aggregate
from_field = key.replace('$', '')
AttributeError: 'int' object has no attribute 'replace'
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I would think that pymongo would evaluate it to this mongodb statement:
db.foo_baz.aggregate({{$group: {_id: '$baz_id', count: {$sum: 1}}}])
Which gives me the expected result when ran from mongodb console, which is: {"_id" : NumberInt("1234"), "count" : 1} in my case.
What am I doning wrong? I am using pymongo 3.4 and python 3.6 and mongomock 3.7.
I have also tried replacing 1 with "1" which does not crash, but gives an incorrect result: ({"_id" : NumberInt("1234"), "count" : NumberInt("0")})
