Lambda Exception

Question

We are using customauth for cognito for verify auth challenge lambda we are using below handler

public CognitoUserPoolVerifyAuthChallengeResponseEvent handleRequest(CognitoUserPoolVerifyAuthChallengeResponseEvent cognitoUserPoolVerifyAuthChallengeResponseEvent, Context context)

we are getting the below error
"An error occurred during JSON parsing: java.lang.RuntimeException
java.lang.RuntimeException: An error occurred during JSON parsing
Caused by: java.io.UncheckedIOException: com.amazonaws.lambda.thirdparty.com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of `java.util.LinkedHashMap` (although at least one Creator exists): no String-argument constructor/factory method to deserialize from String value"

Answer

Hi, 
Can you check the json structure passed in the CognitoUserPoolVerifyAuthChallengeResponseEvent.Request? The request should be in the format 
`{
    "request": {
        "userAttributes": {
            "string": "string",
            . . .
        },
        "privateChallengeParameters": {
            "string": "string",
            . . .
        },
        "challengeAnswer": "string",
        "clientMetadata": {
            "string": "string",
            . . .
        },
        "userNotFound": boolean
    },
    "response": {
        "answerCorrect": boolean
    }
}`.

The json object "privateChallengeParameters" is usually generated in the previous Create auth challenge lambda. Pls verify that structure is getting generated correctly along with the structure of the entire request. Please refer to the following links for further details.
https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-identity-pools-working-with-aws-lambda-triggers.html

https://javadoc.io/static/com.amazonaws/aws-lambda-java-events/3.11.0/com/amazonaws/services/lambda/runtime/events/CognitoUserPoolVerifyAuthChallengeResponseEvent.Request.html

Lambda Exception

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