Python: converting csv to dict - using headers as keys

Question

Python: 3.x

Hi. i have below csv file, which has header and rows. rows count may vary file to file. i am trying to convert this csv to a dict format and data is being repeated for first row.

"cdrRecordType","globalCallID_callManagerId","globalCallID_callId"
1,3,9294899
1,3,9294933

Code:

parserd_list = []
output_dict = {}
with open("files\\CUCMdummy.csv") as myfile:
    firstline = True
    for line in myfile:
        if firstline:
            mykeys = ''.join(line.split()).split(',')
            firstline = False
        else:
            values = ''.join(line.split()).split(',')
            for n in range(len(mykeys)):
                output_dict[mykeys[n].rstrip('"').lstrip('"')] = values[n].rstrip('"').lstrip('"')
                print(output_dict)
                parserd_list.append(output_dict)
#print(parserd_list)

(Generally my csv column count is more than 20, but i have presented a sample file.)

(i have used rstrip/lstrip to get rid of double quotes.)

Output getting:

{'cdrRecordType': '1'}
{'cdrRecordType': '1', 'globalCallID_callManagerId': '3'}
{'cdrRecordType': '1', 'globalCallID_callManagerId': '3', 'globalCallID_callId': '9294899'}
{'cdrRecordType': '1', 'globalCallID_callManagerId': '3', 'globalCallID_callId': '9294899'}
{'cdrRecordType': '1', 'globalCallID_callManagerId': '3', 'globalCallID_callId': '9294899'}
{'cdrRecordType': '1', 'globalCallID_callManagerId': '3', 'globalCallID_callId': '9294933'}

this is the output of print inside for loop. and final output is also the same.

i dont know what mistake i am doing. Someone please help correct it.

thanks in advance.

Answer 1

Instead of manually parsing a CSV file, you should use the csv module.

This will result in a simpler script and will facilitate gracefully handling edge cases (e.g. header row, inconsistently quoted fields, etc.).

import csv

with open('example.csv') as csvfile:
    reader = csv.DictReader(csvfile)
    for row in reader:
        print(row)

Output:

$ python3 parse-csv.py
OrderedDict([('cdrRecordType', '1'), ('globalCallID_callManagerId', '3'), ('globalCallID_callId', '9294899')])
OrderedDict([('cdrRecordType', '1'), ('globalCallID_callManagerId', '3'), ('globalCallID_callId', '9294933')])

---

If you're intent on parsing manually, here's an approach for doing so:

parsed_list = []
with open('example.csv') as myfile:
    firstline = True
    for line in myfile:
        # Strip leading/trailing whitespace and split into a list of values.
        values = line.strip().split(',')

        # Remove surrounding double quotes from each value, if they exist.
        values = [v.strip('"') for v in values]

        # Use the first line as keys.
        if firstline:
            keys = values
            firstline = False
            # Skip to the next iteration of the for loop.
            continue

        parsed_list.append(dict(zip(keys, values)))

for p in parsed_list:
    print(p)

Output:

$ python3 manual-parse-csv.py
{'cdrRecordType': '1', 'globalCallID_callManagerId': '3', 'globalCallID_callId': '9294899'}
{'cdrRecordType': '1', 'globalCallID_callManagerId': '3', 'globalCallID_callId': '9294933'}