DynamoDB WingLib will not deploy to AWS without startingPosition, but this is not documented

[boyney123]

Use Case

Using the WingLib for DynamoDB trying to deploy my application to AWS with terraform. Says the startingPosition is required, but nothing states this in the documentation or examples.

Proposed Solution

Add missing docs.

Implementation Notes

No response

Component

No response

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[Chriscbr]

@boyney123 Can you include an example or the error message in full?

[boyney123]

Yeah sure

here is the error

 Error: creating Lambda Event Source Mapping (arn:aws:dynamodb:us-east-1:654654508474:table/SpacesTable/stream/2024-09-30T10:24:17.260): operation error Lambda: CreateEventSourceMapping, https response error StatusCode: 400, RequestID: 497bc8b2-d962-4f09-bb50-187a59a3e650, InvalidParameterValueException: 1 validation error detected: Value null at 'startingPosition' failed to satisfy constraint: Member must not be null.

So a DDB stream to a Lambda function

This example won't work as the startingPosition is not defined.

db.setStreamConsumer(inflight (record: dynamodb.StreamRecord) => {
     // LOGIC....
});

This works

db.setStreamConsumer(inflight (record: dynamodb.StreamRecord) => {
     // LOGIC....
}, { startingPosition: "LATEST" });

@Chriscbr what you think? Should we default this value for folks in in the winglib? Maybe default to LATEST? Or somehow give them errors to help them at least?

[Chriscbr]

Default to LATEST sounds reasonable.

[boyney123]

Will try and make the change

[boyney123]

OK PR open winglang/winglibs#324