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mongodbamazon-web-servicesaws-lambdaamazon-sqsaws-event-bridge

"Error sending event to AWS EventBridge: SerializationError: failed to unmarshal response" with MongoDB trigger connected to AWS EventBridge

I have created a MongoDB trigger on a collection with Create, Update, Replace and Delete enabled. Document Preimage is also enabled.
I have connected the trigger to AWS EventBridge. From the EventBridge I'm capturing the events and triggering a Lambda Function with an SQS between the Event bus and the Lambda.

I was testing the the trigger but noticed that the Lambda is not triggering and went on to see the Mongo DB trigger logs from MongoDB Atlas. It showed errors with the following message

Error:
Error sending event to AWS EventBridge: SerializationError: failed to unmarshal response error
    status code: 413, request id: 
caused by: UnmarshalError: error message missing

I'm not sure what's causing this. Is it something wrong on MongoDB end or AWS end. I couldn't find anything related to this by googling.

Solution

  • 413 error happens when request size is above 256K. The solution is to specify a Projection Expression for the trigger to select only what's needed and reduce the size.

    Source: https://www.mongodb.com/community/forums/t/error-sending-event-to-aws-eventbridge-serializationerror-failed-to-unmarshal-response-error-with-mongodb-trigger-connected-to-aws-eventbridge/172244/5