short_message field in graylog output hard set to "telegraf"

[dutchman80]

The graylog output plugin is hard setting the required "short_message" field in the GELF message to the string "telegraf". This is happening on line 217 of the output plugin.

It should be setting it to whatever the "short_message" (or "message") field is in the input metric. The way it works now, the actual log messages from the logparser input are not actually passed to Graylog properly.

I don't know 'go' at all or I would have done a pull request with proper error handling.

System info:

telegraf-1.12.5-1

Expected behavior:

Something like...
m["short_message"] = metric.Fields()["short_message"]

Actual behavior:

m["short_message"] = "telegraf"

[danielnelson]

This plugin could definitely use some updates, but we need to be mindful about backwards compatibility. I think it would make sense to add an option to control how the field is set:

[[outputs.graylog]]
  short_message_field = "message"

If the metric doesn't have this field set, or if the option is unset, then we would fall back to the static "telegraf" string. What do you think?

[dutchman80]

I think that would work great!

[danielnelson]

@dutchman80 Are you able to test out one of these builds: #6700 (comment)?