DynamoDB.putItem 未保存

Question

this code is called after Cognito signup postConfirmation, the dynamo.putItem is not working and is not logging to Cloudwatch. I've tried to add CloudTrail logs but they are not showing anything.

What is the reason ?

Thanks for your help !

...

module.exports.router = async (event, context) => {
    if (process.env.npm_lifecycle_event !== "test") {
        console.debug("event", event);
        console.debug("context", context);
    }
    let response = null;
 
    if (event.userPoolId) {
        if (event.userPoolId == process.env.COGNITO_POOL) {
            try {
                
                if (event.triggerSource == 'PostConfirmation_ConfirmSignUp') {
 
                    const now = new Date().toISOString();
                    var actual = {
                        userName: event.userName,
                        created: now,
                        publicKey: "la mia chiave pubblica",
                        privateKey: "la mia chiave privata"
                    };
 
                    dynamo.putItem({
                        ReturnConsumedCapacity: "TOTAL",
                        TableName: process.env.USERS_TABLE,
                        Item: converter.marshall(actual)
                    }, (_err, _data) => {
                        console.debug("into putItem !!!");
                         
                        if (_err) {
                            console.log("error", _err);
                        } else {
                            console.log("added", _data);
                        }
                    });
 
                } else {
                     
                }                               
            } catch (error) {
                console.log(error);
            }           
            response = event;
        } else {
            throw new Error(`Wrong pool event.userPoolId`);
        }
    } else {
        throw new Error(`No pool`);
    }
    return response; 
}

Answer 1

You are not waiting for dynamo.putItem to complete, the Lambda function is shutting down before a network request is made.

Since you have set your function to be async, you should call .promise() on the putItem() method so that it returns a promise. you can then await the promise so that the lambda does not stop until the DynamoDB call succeeds.