logical error in python dictionary traversal

Question

one of my queries in mongoDB through pymongo returns:

{ "_id" : { "origin" : "ABE", "destination" : "DTW", "carrier" : "EV" }, "Ddelay" : -5.333333333333333,
 "Adelay" : -12.666666666666666 }
{ "_id" : { "origin" : "ABE", "destination" : "ORD", "carrier" : "EV" }, "Ddelay" : -4, "Adelay" : 14 }

{ "_id" : { "origin" : "ABE", "destination" : "ATL", "carrier" : "EV" }, "Ddelay" : 6, "Adelay" : 14 }

I am traversing the result as below in my python module but I am not getting all the 3 results but only two. I believe I should not use len(results) as I am doing currently. Can you please help me correctly traverse the result as I need to display all three results in the resultant json document on web ui. Thank you.

code:

pipe = [{ '$match': { 'origin': {"$in" : [origin_ID]}}},
             {"$group" :{'_id': { 'origin':"$origin", 'destination': "$dest",'carrier':"$carrier"},
             "Ddelay" : {'$avg' :"$dep_delay"},"Adelay" : {'$avg' :"$arr_delay"}}}, {"$limit" : 4}]
    results = connect.aggregate(pipeline=pipe)
    #pdb.set_trace()
    DATETIME_FORMAT = '%Y-%m-%d'
    for x in range(len(results)):
        origin = (results['result'][x])['_id']['origin']
        destination = (results['result'][x])['_id']['destination']
        carrier = (results['result'][x])['_id']['carrier']
        Adelay = (results['result'][x])['Adelay'] 
        Ddelay = (results['result'][x])['Ddelay']        
        obj = {'Origin':origin,
                'Destination':destination,
                'Carrier': carrier,
                'Avg Arrival Delay': Adelay,
                'Avg Dep Delay': Ddelay}
        json_result.append(obj)
    return json.dumps(json_result,indent= 2, sort_keys=False,separators=(',',':'))

Answer 1

Pymongo returns result in format:

{u'ok': 1.0, u'result': [...]}

So you should iterate over result:

for x in results['result']:
    ...

In your code you try to calculate length of dict, not length of result container.