External Lookup and return value

[cburling61]

Hello. I am running fluent v1.15.3 and I have an instance where I want to take a key value from the log event being processed and use that as a key to lookup in an external json formatted file and return the value that is associated with that key. I have tried using the exec and exec_filter with no luck. I have a python3 script that takes the key as a variable and running that external to Fluentd works. Al of the lookup plugins I have found have not been updated in many years and do not work under the current version from what I can tell. Has anyone successfully done this and can share how they got it to work? Thanks in advance.