add invocation ids for plain text logs

[adamantal]

In case the Lambda logs are of plain text format, they are not enriched with the requestId information (link to API reference).

I am well aware that logging in json format is preferred, but I think manually enriching the logs with this attribute can be beneficial in at least two cases:

• even if the application code logs in json format, static init/teardown of the function may be in plain text format - e.g. an entrypoint that prints out some message which still belongs to the same invocation
• legacy apps (boring, but also our use case)

Tested internally on some of our Lambdas

[linux-foundation-easycla]

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• ✅ login: adamantal / name: Adam Antal (d10d9d4, 0b68ef8)

[tylerbenson]

Do you have a screenshot of what the logs before/after look like?

[adamantal]

Sure, here's an example snippet of a Lambda invocation:

You can see some Magnum logs when the invocation starts.

The rest of the observability stack is quite simple honestly. We send logs to Loki's OTLP endpoint, and browse them through Grafana.

We have a few other changes in our internal fork that we'd like to contribute back over time. For example in the screenshot you can see the service_instance_id field. This is not exposed to the Lambda collector from the core Otel SDK by default, so we enrich it manually (which is the equivalent of AWS Cloudwatch log streams).

Let me know if you have any questions. Great project btw

[pragmaticivan]

Not as familiar with this code, but any reason you are not logging the request ID after this line?

[adamantal]

no special reason. I can add a debug level log to this, if it's helpful