record_transformer adding quotes to my json payload.

[ccovarrubias-paradigm]

Hello all. I was hoping to get some help figuring out what's probably a super easy fix. I am running my logs through the record_transformer filter to inject some specific keys. My record["message"] content is json.

<filter mylogs.raw>
  @type record_transformer
  enable_ruby true
  renew_record true
  <record>
    message \{${"\"log_type\": \"application_name\", \"log_level\": \"" + record["loglevel"] + "\", \"payload\":" + record["message"]}\}
  </record>
</filter>

The problem I'm running into is after I run it through the filter, fluentd is wrapping the value in quotes ( { message: "{key...) where as I want the value to be native json. Is there a way in the filter to remove the double quotes?

[kenhys]

It seems that message ${{"log_type": "application_name", "log_level": record["loglevel"], "payload": record["message"]}} is enough.

Here is the sample to emulate:

<source>
  @type dummy
  tag mylogs.raw
  dummy {"loglevel": "info", "message": {"key": "value"}}
</source>

<filter mylogs.raw>
  @type record_transformer
  enable_ruby true
  renew_record true
  <record>
    message ${{"log_type": "application_name", "log_level": record["loglevel"], "payload": record["message"]}}
  </record>
</filter>

<match **>
 @type stdout
</match>

outcome is:

2023-05-02 17:55:40.034551079 +0900 mylogs.raw: {"message":{"log_type":"application_name","log_level":"info","payload":{"key":"value"}}}