DocumentDB Lambda Trigger support?

[bneigher]

Is there an existing issue for this?

• I have searched existing issues, it hasn't been reported yet

Use case description

Hello Serverless! On Feb 28th 2023, aws announced DocumentDB CDC lambda triggers support. This is a powerful feature that replaces existing approaches (polling, or AWS DMS migrations).

It doesn't seem like currently serverless supports this trigger. Do you guys plan on adding it and if so, when can we expect to have it released?

Much appreciated!

Proposed solution (optional)

It looks like it would be a relatively simple (basic) configuration.

[bneigher]

Additional Resource references:

https://docs.aws.amazon.com/lambda/latest/dg/with-documentdb.html#docdb-prereqs
https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-property-function-documentdb.html

[medikoo]

@bneigher thanks for openning that.

To me it feels as third option for our stream event. Still as there's a call to split stream event into separate events (#8137), instead I'll introduce a new documentDb event. WDYT?

If anyone wants to take the effort and implement it, I believe we should start with a short spec outlining what properties will new event support

[bneigher]

I think either approach is fine. I haven't used the trigger yet manually yet so I don't have any feedback on what the spec would look like. Appreciate the triage @medikoo!

[bneigher]

hey @medikoo! just wanted to get an approximate estimate on when we can expect this feature to get released into serverless? trying to figure out non click-ops alternatives and knowing when we may expect this feature to roll out will inform the decision making. thank you!

[medikoo]

@bneigher we do not have the capacity to address it in our scope. Therefore we'll accept the contribution from the community. Can you work on that?

[bneigher]

@medikoo ah ok. I took a look and I think I see in general where to add the code, but I don't have the time to figure out how to test this, ect as I'm pretty swamped. So I don't think I'll be able to add this feature myself. Also it's unclear from the documentation the actions internally that I need to add under the rds service (other than these)

rds:DescribeDBClusters
rds:DescribeDBClusterParameters
rds:DescribeDBSubnetGroups

which are equivalent to the policy statements listed for dynamodb and kinesis in the /lib/plugins/aws/package/compile/events/stream.js

so I will explore alternative means to add this trigger to my lambda deployment pipeline.. cc @westergaards