[Tutor] cgi module help (original poster)

[rmlibre at riseup.net]

On 2019-08-13 15:49, tutor-request at python.org wrote:
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>    1. Re: Fwd: Re: HELP PLEASE (Alan Gauld)
>    2. Re: HELP PLEASE (David L Neil)
>    3. Re: HELP PLEASE (Cameron Simpson)
>    4. Re: HELP PLEASE (Sithembewena L. Dube)
>    5. Re: HELP PLEASE (Alan Gauld)
>    6. Re: cgi module help (Peter Otten)
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I went looking through the cgi module code and found the limitation is
in the way urllib's parse_qsl method parses data. It simply does not
handle nested dictionaries correctly. This lead to a simple
solution/hack by just json'ing the nested values:

"""Client Code"""
import json
from requests import sessions

inner_metadata = json.dumps({"date": "2019-08", "id": "0000"})
metadata = {"metadata": inner_metadata}
session = sessions.Session()
session.post(<url>, data=metadata)


This is received on the server side and can be parsed with:

"""Server Code"""
import cgi
import json

form = cgi.FieldStorage()
metadata_json = form.getvalue("metadata", None)
metadata = json.loads(metadata)
print(metadata)
> {"date": "2019-08", "id": "0000"}

print(type(metadata))
> dict