Answer to the previous exercise: Handler2 is the first one that can handle the request, so its handle method will be executed.

Now let’s write some request handlers!

One of your skill’s intents is the HelloIntent, which expects a greeting like “Hello, John”. We can name the handler anything, but for clarity let’s call the handler HelloHandler:

const HelloHandler = {
  canHandle(handlerInput) {
  },
  handle(handlerInput) {
  },
};

The handler can handle the request if the request type is 'IntentRequest' and the request intent name is 'HelloIntent':

 canHandle(handlerInput) {
    return handlerInput.requestEnvelope.request.type === 'IntentRequest'
      && handlerInput.requestEnvelope.request.intent.name === 'HelloIntent';
  }

We learned that the SDK will ‘ask’ each handler if they can handle the request. What’s really happening is this:

1. The SDK calls the handlers’ canHandle method with the argument handlerInput. This contains information about the request sent by the Alexa Service. It’s in the form of JSON, which can be treated like a JavaScript object.
2. The canHandle method contains conditional logic which returns either true, if it can handle the request, or false, if it cannot.
3. If the canHandle method returns true, the SDK calls the handlers handle method. If false, the process repeats with the next handler in the sequence.