What is the c# equivalent of context.fail(response)?

Question

I'm seeing a lot of examples for node.js to fail a lambda using context.fail(response).

What is the c# equivalent of context.fail(response) since the ILambdaContext for c# doesn't have fail or succeed methods on it?

Answer 1

In the Node.js version 0.10.42 runtime the context contained methods for succeed, fail, and done[1]. This model was replaced with a callback model which removed the methods from the context and errors are passed from a callback[2].

In the C# programming model the analogous is to throw an exception[3].

From the docs:

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

• Initialization (Lambda loading your code, validating the handler string, and creating an instance of your class if it is non-static).
• The Lambda function invocation.

An example is given where an exception is thrown from a Handler:

namespace Example {            
   public class AccountAlreadyExistsException : Exception {
      public AccountAlreadyExistsException(String message) :
         base(message) {
      }
   }
} 

namespace Example {
   public class Handler {
     public static void CreateAccount() {
       throw new AccountAlreadyExistsException("Account is in use!");
     }
   }
}

[1]: Using Earlier Node.js Runtime (v0.10.42)

[2]: Function Errors (Node.js)

[3]: Function Errors (C#)