uses for aws lambda functions code example

Example 1: aws cli lambda

aws lambda create-function \
    --function-name my-function \
    --runtime nodejs10.x \
    --zip-file fileb://my-function.zip \
    --handler my-function.handler \
    --role arn:aws:iam::123456789012:role/service-role/MyTestFunction-role-tges6bf4

Example 2: aws lambda tutorial

callback();                // It will return success, but no indication to the caller
callback(null);            // It will return success, but no indication to the caller
callback(null, "success"); // It will return the success indication to the caller
callback(error);           //  It will return the error indication to the caller