WebUI API: Spaces Encoded as Plus Signs (ie + ) in Query Parameters Are Not Interpreted as Spaces and Instead Become Part of the Parameter

[rmartin16]

qBittorrent version and Operating System

qBittorrent 4.1.5
Linux (Ubuntu)

If on linux, libtorrent and Qt version

libtorrent 1.1.13.0
Qt 5.12.2

What is the problem

When a space in a query parameter is encoded with a + (plus sign) in a GET request, qBittorrent interprets the plus sign as part of the query parameter value. It appears that query parameters must be percent encoded. Based on what I've read, that makes sense since the plus sign was never actually part of the URL spec. That aside, it definitely happens. Spaces encoded as plus signs in the body of POST (application/x-www-form-urlencoded) requests are interpreted correctly. (Although, the internet suggests this is where the plus sign encoding in URLs came from...)

Case in point, I've been implementing an API client in Python and the requests module will encode spaces in query parameters as plus signs.

I did find the workaround below to ensure query parameters are percent encoded....a bit wonky though.

payload = {'caetgory': 'delete after upload'}
params = urllib.parse.urlencode(payload, quote_via=urllib.parse.quote)
requests.request('get', 'http://localhost:8080/api/v2/torrents/info', cookies={'SID': '...'}, params=params).json()

That said, a POST requests also works around this problem.

What is the expected behavior

Interpret '+' symbols in the query parameters as spaces and %2B as plus signs.

Steps to reproduce

Make the query below:
http://localhost:8080/api/v2/torrents/info?category=delete+after+upload

Extra info(if any)

Endpoints most likely to be affected:
torrents/info
search/categories

[Chocobo1]

PR #10607 should fix it.