Cannot use timeout for inputs.prometheus plugin with v1.26.0

[jheinitz]

Relevant telegraf.conf

# Original Config:
# ----------------
[[inputs.prometheus]]
   urls = ["http://127.0.0.1:8779/metrics"]
   username = "*****"
   password = "*****"
   response_timeout = "10s"
   [inputs.prometheus.tags]
     component = "kafka"

# Adapted Config:
# ----------------
[[inputs.prometheus]]
   urls = ["http://127.0.0.1:8779/metrics"]
   username = "*****"
   password = "*****"
   # response_timeout = "10s"
   timeout = "10s"
   [inputs.prometheus.tags]
     component = "kafka"

Logs from Telegraf

Log for Original Config:
------------------------
2023-03-14T10:20:25Z I! Loading config file: /etc/telegraf/telegraf.d/in.jmx_prometheus-kafka.conf
2023-03-14T10:20:25Z W! DeprecationWarning: Option "response_timeout" of plugin "inputs.prometheus" deprecated since version 1.26.0 and will be removed in 2.0.0: use 'timeout' instead

Log for Adapted Config:
-----------------------
2023-03-14T10:21:40Z I! Loading config file: /etc/telegraf/telegraf.d/in.jmx_prometheus-kafka.conf
2023-03-14T10:21:40Z E! error loading config file /etc/telegraf/telegraf.d/in.jmx_prometheus-kafka.conf: error parsing prometheus, line 6: field corresponding to `timeout' in prometheus.Prometheus cannot be set through TOML

System info

Telegraf v1.26.0, RHEL 8.6 Docker 20.10.17

Docker

No response

Steps to reproduce

1. Use original config from above
2. Launch telegraf container
3. see warning in log (see above)
4. modify config to use timeout instead of response_timeout
5. restart telegraf container
6. see error in log (see above)
   ...

Expected behavior

Telegraf should no longer issue a warning and accept the new parameter timeout = "10s" and should start up.

Actual behavior

Telegraf complains about the parameter timeout = "10s" and does not start

Additional info

No response

[powersj]

@jheinitz,

Thanks for the quick issue. I have put up #12864 with a fix, it seems we did not get the deprecation quite right. For now, you can continue to use response_timeout to set the timeout.

Thanks again

[jheinitz]

Hello,

I just wanted to let you know that I validated the fix using the latest nightly. The deprecation warning is only shown when the response_timeout parameter is present and I was able to add the timeout: parameter.

Thanks for the quick fix and for your great work!

Kind regards

Jens

[powersj]

Thank you for confirming!