Alexa Lambda Handler

Alexa Lambda Handler is a helper class that defines injection points for routing Alexa Skill requests hosted on AWS Lambda. Depends on Alexa.NET Nuget package.

Usage

1. Add a reference to AlexaLambdaHandler using Nuget.
2. Make your AWS Lambda handler class derive from AlexaLambdaHandler.LambdaHandler abstract class.
3. Add handlers inside the constructor.
4. Call await Handle(input, context) in your AWS Lambda handler method and return the output.

Code Sample

// Assembly attribute to enable the Lambda function's JSON input to be converted into a .NET class.
[assembly: LambdaSerializer(typeof(Amazon.Lambda.Serialization.Json.JsonSerializer))]
namespace MyAlexaSkillLambda
{
    public class Function : LambdaHandler
    {

        public Function()
        {
            AddAsyncIntentRequestHandler("SomeCustomIntent", HandleCustomIntent);

            SystemExceptionRequestHandler = (request, exceptionRequest, context) =>
             {
                 context.Logger.Log($"ERROR: {exceptionRequest.Error.Message}");
                 return Task.FromResult(ResponseBuilder.Empty());
             };
        }

        public async Task<SkillResponse> FunctionHandler(SkillRequest input, ILambdaContext context)
        {
            return await Handle(input, context);
        }

        internal async Task<SkillResponse> HandleLaunchRequest(SkillRequest request, LaunchRequest launchRequest, ILambdaContext context)
        {
            ...
        }

        internal async Task<SkillResponse> HandleCustomIntent(SkillRequest request, IntentRequest intentRequest, ILambdaContext context)
        {
            ...
        }

    }
}

AWS Lambda Handler string for the above class is "MyAlexaSkillLambda::MyAlexaSkillLambda.Function::FunctionHandler".

API Definition

Property LambdaHandler.AudioPlayerRequestHandler

Get/set handler for audio player requests.

Property LambdaHandler.IntentRequestHandlers

Get/set handler for intent requests, both built-in and custom.

Property LambdaHandler.DefaultIntentRequestHandler

Get/set handler for default intent requests. This handler will be used when an intent name does not match any known intents. Register known intents using LambdaHandler.AddIntentRequestHandler() method.

Property LambdaHandler.LaunchRequestHandler

Get/set handler for launch requests.

Property LambdaHandler.PlaybackControllerRequestHandler

Get/set handler for playback controller requests.

Property LambdaHandler.SessionEndedRequestHandler

Get/set handler for session end requests.

Property LambdaHandler.SystemExceptionRequestHandler

Get/set handler for system exception requests.

Property LambdaHandler.DefaultHandler

Get/set default handler. Default handler will be used when no handler is set for a request. For intent requests, default handler will be used when handling unknown intent and LambdaHandler.DefaultIntentRequestHandler is not set.

Method LambdaHandler.AddIntentRequestHandler() and LambdaHandler.AddAsyncIntentRequestHandler()

Add a handler for a specific intent name. Built-in intents are prefixed with "AMAZON.", e.g. "AMAZON.HelpIntent".

Method LambdaHandler.Handle()

Perform routing of request into one of the configured handlers. Call this and return the output on your AWS Lambda handler function.

Code sample:

public async Task<SkillResponse> FunctionHandler(SkillRequest input, ILambdaContext context)
{
    return await Handle(input, context);
}