Custom JSONEncoder for requests.post

Question

I'm writing wrapper for REST API and use requests module.

Method .json() of Response object transfers **kwargs to json.loads() function, so I can easily use custom JSON decoder and, i. e. transparently convert UNIX epoch timestamps to datetime.datetime objects.

Is there any way to use custom JSON encoder with Request object? Seems I can only use parameter json, but can't find how to use custom JSON encoder with it.

What are you **actually** trying to do? [This question looks very XY to me](http://meta.stackexchange.com/questions/66377/what-is-the-xy-problem) — UmNyobe, Dec 19 '15 at 01:49
This is probably relevant: https://github.com/kennethreitz/requests/issues/2755. — alecxe, Dec 19 '15 at 02:00
alecxe, seems that's the answer for my question, thank you. Could you make it a separate answer? — Valery Ryaboshapko, Dec 19 '15 at 02:16

Jesse · Accepted Answer · 2022-04-23T13:16:36.347

46

Extracting the answer from the link provided by alecxe, using a custom encoder and the json parameter is not supported. It's recommended you just construct the post manually.

r = requests.post('http://foo.bar',
              data=json.dumps(some_data, cls=CustomJSONEncoder),
              headers={'Content-Type': 'application/json'})

edited Apr 23 '22 at 13:16

answered Mar 27 '17 at 19:46

Jesse

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Thanks! Also, small note, when using `json=...`, requests adds a `content-type` value of `application/json`, which some servers expect. When calling requests with your own-encoded JSON payload, you may have to add `headers={'content-type': 'application/json'}` (again, depending if the server you're interacting with cares about this or not) – Greg Sadetsky Jul 07 '21 at 19:19

Custom JSONEncoder for requests.post

1 Answers1