Combine Python dictionaries that have the same Key name

Question

I have two separate Python List that have common key names in their respective dictionary. The second list called recordList has multiple dictionaries with the same key name that I want to append the first list clientList. Here are examples lists:

clientList = [{'client1': ['c1','f1']}, {'client2': ['c2','f2']}]
recordList = [{'client1': {'rec_1':['t1','s1']}}, {'client1': {'rec_2':['t2','s2']}}]

So the end result would be something like this so the records are now in a new list of multiple dictionaries within the clientList.

 clientList = [{'client1': [['c1','f1'], [{'rec_1':['t1','s1']},{'rec_2':['t2','s2']}]]}, {'client2': [['c2','f2']]}]

Seems simple enough but I'm struggling to find a way to iterate both of these dictionaries using variables to find where they match.

Answer 1

Assuming you want a list of values that correspond to each key in the two lists, try this as a start:

from pprint import pprint

clientList = [{'client1': ['c1','f1']}, {'client2': ['c2','f2']}]
recordList = [{'client1': {'rec_1':['t1','s1']}}, {'client1': {'rec_2':['t2','s2']}}]
clientList.extend(recordList)

outputList = {}

for rec in clientList:
    k = rec.keys()[0]
    v = rec.values()[0]
    if k in outputList:
        outputList[k].append(v)
    else:
        outputList[k] = [v,]

pprint(outputList)

It will produce this:

{'client1': [['c1', 'f1'], {'rec_1': ['t1', 's1']}, {'rec_2': ['t2', 's2']}],
 'client2': [['c2', 'f2']]}

Answer 2

This could work but I am not sure I understand the rules of your data structure.

# join all the dicts for better lookup and update
clientDict = {}
for d in clientList:
    for k, v in d.items():
        clientDict[k] = clientDict.get(k, []) + v

recordDict = {}
for d in recordList:
    for k, v in d.items():
        recordDict[k] = recordDict.get(k, []) + [v]

for k, v in recordDict.items():
    clientDict[k] = [clientDict[k]] + v

# I don't know why you need a list of one-key dicts but here it is
clientList = [dict([(k, v)]) for k, v in clientDict.items()]

With the sample data you provided this gives the result you wanted, hope it helps.