Params and headers - None value (and comparison with requests)

[delicb]

I am working on migrating an HTTP library from requests to httpx. One of the differences I noticed (which matter for me in final implementation) is treatment of None values in params and headers. Requests just does not send params if they have None value, while httpx sends query parameter but without value and raises exceptions for headers.

What requests does seems more intuitive to me. Is this deliberate design decision and is it subject to change? I can handle it on my end, but it seems like something that should be part of httpx.

For headers requests does not send None values, while httpx fails with AttributeError: 'NoneType' object has no attribute 'encode'. IMO - at very least it should not fail.

Example:

import httpx
import requests
import pytest

def test_compare_httpx_requests_params():
    import httpx
    import requests
    params = {"exists": "yes", "multi": [1, 2], "not-exists": None}
    req_res = requests.get("https://httpbin.org/get", params=params).json()["args"]
    httpx_res = httpx.get("https://httpbin.org/get", params=params).json()["args"]
    print(req_res)  # prints: {'exists': 'yes', 'multi': ['1', '2']}
    print(httpx_res)  # {'exists': 'yes', 'multi': ['1', '2'], 'not-exists': ''}


def test_compare_httpx_requests_headers():
    headers = {"X-H1": "yes", "X-H2": None}
    req_res = requests.get("https://httpbin.org/get", headers=headers).json()["headers"]
    with pytest.raises(AttributeError):
        httpx.get("https://httpbin.org/get", headers=headers).json()  # raises AttributeError
    print(req_res)  # prints headers including only X-H1

I think I saw discussion about overwriting client params in concrete request - this might be a solution to that as well (send None for concrete value).

What do you think?

[Fury1]

I just ran into this today myself switching over from requests with a "params" argument in GET requests.

I did find this -> https://www.python-httpx.org/compatibility/#query-parameters

Seems like it is a documented design choice as httpx aims to be mostly compatible but not a drop in replacement.

I just made a payload filter to handle things:

f_payload = {k: v for k, v in payload.items() if v is not None}