inputs.http plugin does not respect token_file

[jyrkih]

Relevant telegraf.conf

[[inputs.http]]

  ## One or more URLs from which to read formatted metrics.
  urls = [
    "https://xxxxxx",
  ]
  token_file = "/tmp/bearer_token_file"

Logs from Telegraf

docker-telegraf-1  | 2023-11-27T14:00:00Z E! [inputs.http] Error in plugin: [url=https://xxxxxx]: open : no such file or directory

System info

Telegraf 1.28.5

Docker

FROM telegraf:latest

Steps to reproduce

1. define custom bearer token using token_file

...

Expected behavior

http input plugin should open the file containing the bearer token

Actual behavior

error which says that file cannot be opened.

Additional info

I think it's part in http.go:

} else if h.TokenFile != "" {
token, err := os.ReadFile(h.BearerToken)

I.e. it tries to open file given in the deprecated bearer_token

[powersj]

Thank you for taking the time to file and issue and even find the root cause. I have put up #14350 with a fix.