[Bug] Question mark in user_secret gets encoded wrong

[ljvdhooft]

Describe the bug

When you use a question mark in the client_secret with OAuth2, the question mark doesn't get encoded properly.

Steps to reproduce

• Add Infinity as data source
• Configure Authentication to OAuth2, Auth style "In Header"
• Add a question mark client_id and client_secret
• Perform the test request to a mock server
• Read out the request headers and compare them to another base64 encoder.

Sample Data

  % echo -n '?:?' | base64                                                                                                                                                                                                             
Pzo/

When retrieving the base64 encoded string from Infinity:
authorization: "Basic JTNGOiUzRg=="

Decoding this string results in:

  % echo -n 'JTNGOiUzRg==' | base64 --decode                                                                                                                                                                                          
%3F:%3F%

Version Details:

• Grafana version : v11.1.4
• Plugin version : 2.10.0

[ljvdhooft]

After some more testing it seems to happen with other special characters as well, exclamation mark (!) doesn't work either