If you have logging enabled for your lambda function, you should be able to see the names of the fields available. When looking at them, remember it will be broken down by a header section and then a list of items. The context for item is limited to the scope of that log line, but the payload you are currently working in has a scope in the javascript of parsed . For my use case, I found that I was looking for parsed.logGroup to get the name of the log group as it appears in CloudWatch to appear as my source.
Hope this is still relevant to you, or others!
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