NXLog: Json input to GELF UDP Output - json

Question

We have a setup where a program logs to a .Json file, in a format that follows the GELF specification.
Currently this is sent to a Graylog2 server using HTTP. This works, but due to the nature of HTTP there's a significant latency, which is an issue if there is a large amount of log messages.
I want to change the HTTP delivery method to UDP, in order to just 'fire and forget'.
The logs are written to files like this:
{ "short_message": "<message>", "host": "<host>", "full_message": "<message>", "_extraField1": "<value>", "_extraField2": "<value>", "_extraField3": "<value>" }
Current configuration is this:
<Extension json>
Module xm_json
</Extension>
<Input jsonLogs>
Module im_file
File '<File Location>'
PollInterval 5
SavePos True
ReadFromLast True
Recursive False
RenameCheck False
CloseWhenIdle True
</Input>
<Output udp>
Module om_udp
Host <IP>
Port <Port>
OutputType GELF_UDP
</Output>
With this setup, part of json log message is added to the "message" field of a GELF message, and sent to the server.
I've tried adding the line `Exec parse_json(), but this will simply result in all fields other than short_message and full_message being excluded.
I'm unsure how to configure this correctly. Even just having the complete log message added to a field is preferable, since I can add an extractor on the server side.

Answer 1

You'd need Exec parse_json() in order for GELF_UDP to generate proper output but it was unclear what the exact issue is with message and full/short_message.
Another option you could try is simply ship the log via om_tcp. In this case you'll not need to use OutputType GELF_TCP since it is already formatted that way.