Amazon Kinesis Firehose: Set index depending on Cloudwatch Log Group name in Lambda Function

[knam]

I recently setup Kinesis Firehose to push to Splunk HEC which is ingesting fine, however, I would like to have the logs sent to "nonprod" or "prod" index depending on the cloudwatch log group name.

For example, if cloudwatch log group name is like "prod", go to prod-index. Else, go to nonprod-index.

I'm utilizing this python script for my lambda function (Cloudwatch2FH2HEC.py) and tried editing the area below but I believe this is nested in the lower JSON and will not matter.
Edit: Hyperlink didn't work
https://github.com/ptdavies17/CloudwatchFH2HEC
https://github.com/ptdavies17/CloudwatchFH2HEC/blob/master/Cloudwatch2FH2HEC.py

Working version:

if "CloudTrail" in loggrp:
    sourcetype="aws:cloudtrail"
elif "VPC" in loggrp:
    sourcetype="aws:cloudwatchlogs:vpcflow"
else:
    sourcetype=os.environ['SPLUNK_SOURCETYPE']

return_message = '{"time": ' + str(log_event['timestamp']) + ',"host": "' + logstrm  + '","source": "' + loggrp + '"'
return_message = return_message + ',"sourcetype":"' + sourcetype  + '"'
return_message = return_message + ',"event": ' + json.dumps(log_event['message']) + '}\n'

return return_message + '\n'

Attempted version:

if "CloudTrail" in loggrp:
    sourcetype="aws:cloudtrail"
elif "VPC" in loggrp:
    sourcetype="aws:cloudwatchlogs:vpcflow"
else:
    sourcetype=os.environ['SPLUNK_SOURCETYPE']

if "prod" in str.lower(loggrp):
    index="prod-kinesis"
else:
    index="nonprod-kinesis"

return_message = '{"time": ' + str(log_event['timestamp']) + ',"host": "' + logstrm  + '","source": "' + loggrp + '"'
return_message = return_message + ',"sourcetype":"' + sourcetype  + '"'
return_message = return_message + ',"index":"' + index  + '"'
return_message = return_message + ',"event": ' + json.dumps(log_event['message']) + '}\n'

return return_message + '\n'

Any thoughts on how to achieve this?

[knam · Accepted solution]

Issue was with str. Lambda had the following error

descriptor 'lower' requires a 'str' object but received a 'unicode': TypeError
Traceback (most recent call last):
File "/var/task/lambda_function.py", line 213, in handler
records = list(processRecords(event['records'],streamARN))
File "/var/task/lambda_function.py", line 113, in processRecords
data = ''.join([transformLogEvent(e,data['owner'],arn,data['logGroup'],data['logStream'],data['subscriptionFilters'][0]) for e in data['logEvents']])
File "/var/task/lambda_function.py", line 82, in transformLogEvent
if "prod" in str.lower(loggrp):
TypeError: descriptor 'lower' requires a 'str' object but received a 'unicode'

Changed str.lower(loggrp): to unicode.lower(loggrp) and it is now working and sending to prod or nonprod index depending on cloudwatch log group.