There are a lot of AWS errors 
out there. Way too many, right?

Quick fix

Lambda generates a JSON representation of the error, when your code causes an error. This error document occurs in the invocation log. For synchronous invocations, the document appears in the output.

{
  "errorType": "ReferenceError",
  "errorMessage": "x is not defined",
  "trace": [
    "ReferenceError: x is not defined",
    "    at Runtime.exports.handler (/var/task/index.js:2:3)",
    "    at Runtime.handleOnce (/var/runtime/Runtime.js:63:25)",
    "    at process._tickCallback (internal/process/next_tick.js:68:7)"
  ]
}

Best solution:

https://docs.aws.amazon.com/lambda/latest/dg/nodejs-prog-mode-exceptions.html

Quick fix

If your Lambda function triggers an exception, AWS Lambda recognizes the failure and serializes the exception information into JSON and returns it.

{
  "errorMessage": "I failed!",
  "stackTrace": [
    [
      "/var/task/lambda_function.py",
      3,
      "my_always_fails_handler",
      "raise Exception('I failed!')"
    ]
  ],
  "errorType": "Exception"
}

Best solution

https://docs.aws.amazon.com/lambda/latest/dg/python-exceptions.html

Quick fix

Lambda generates a JSON representation of the error, when your code causes an error. This error document occurs in the invocation log. For synchronous invocations, the document appears in the output.

{
  "errorMessage": "no implicit conversion of String into Integer",
  "errorType": "Function",
  "stackTrace": [
    "/var/task/function.rb:3:in `first'",
    "/var/task/function.rb:3:in `handler'"
  ]
}

Best solution:

https://docs.aws.amazon.com/lambda/latest/dg/ruby-exceptions.html

Quick fix

If your Lambda function causes an exception, AWS Lambda recognizes the failure and serializes the exception information into JSON and returns it.

{
  "errorMessage": "Name John Doe is invalid. Exception occurred...",
  "errorType": "java.lang.Exception",
  "stackTrace": [
    "example.Hello.handler(Hello.java:9)",
    "sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)",
    "sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)",
    "sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)",
    "java.lang.reflect.Method.invoke(Method.java:497)"
  ]
}

Best solution:

https://docs.aws.amazon.com/lambda/latest/dg/java-exceptions.html

Quick fix

You can create custom error handling to raise an exception directly from your Lambda function and handle it directly.

{
  "errorMessage": "something went wrong!",
  "errorType": "errorString"
}

Best solution:

https://docs.aws.amazon.com/lambda/latest/dg/go-programming-model-errors.html

Quick fix

When an exception arises in your Lambda function, Lambda will report the exception information back to you. These exceptions can occur in two different places:

• Initialization
• The Lambda function invocation

The serialized exception information is returned as the payload as a modeled JSON object and given out to CloudWatch logs.

In the initializaion phase, exceptions can be thrown for invalid handler strings, a rule-breaking type or method, or any other validation method. These exceptions are of type LambdaExcpetion. 

{
  "errorType": "LambdaException",
  "errorMessage": "Invalid lambda function handler: 'http://this.is.not.a.valid.handler/'. 
  The valid format is 'ASSEMBLY::TYPE::METHOD'."
}

Best solution

https://docs.aws.amazon.com/lambda/latest/dg/dotnet-exceptions.html

Quick fix

When your Lambda function has a terminating error, AWS Lambda recognizes the failure, serializes the error information into JSON, and returns it. 

{
  "errorMessage": "The Account is not found",
  "errorType": "RuntimeException"
}

Best solution

https://docs.aws.amazon.com/lambda/latest/dg/powershell-exceptions.html

More solutions:

https://epsagon.com/blog/how-to-handle-aws-lambda-errors-like-a-pro/

Quick fix

List of Error Codes:

Solution Error 403 Access Denied:

• https://aws.amazon.com/premiumsupport/knowledge-center/s3-troubleshoot-403/
• https://forums.aws.amazon.com/thread.jspa?threadID=56531

Solution Error 503:

• https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/http-503-service-unavailable.html
• https://forums.aws.amazon.com/thread.jspa?threadID=234361

Best solution

https://docs.aws.amazon.com/AmazonS3/latest/API/ErrorResponses.html

ST Best Practices:

https://docs.aws.amazon.com/AmazonS3/latest/dev/ErrorBestPractices.html

Quick fix

When an AWS Lambda fuction is invoked using an AWS SDK, the function times out, execution hangs, or an API action is duplicated.

These issues can arise when:

• You call a remote API that takes too long to respond or that is unreachable.
• Your API call doesn't get a response within the socket timeout.
• Your API call doesn't get a response within the timeout period of your Lambda function.

Best solution

https://aws.amazon.com/premiumsupport/knowledge-center/lambda-function-retry-timeout-sdk/

More solutions:

https://epsagon.com/blog/best-practices-for-aws-lambda-timeouts/