Add i18n to ASK CLI 2.0.x template

lambda/index.js

@@ -2,13 +2,15 @@
 // Please visit https://alexa.design/cookbook for additional examples on implementing slots, dialog management,
 // session persistence, api calls, and more.
 const Alexa = require('ask-sdk-core');
+const i18n = require('i18next');
+const languageStrings = require('./languageStrings');
 
 const LaunchRequestHandler = {
     canHandle(handlerInput) {
         return Alexa.getRequestType(handlerInput.requestEnvelope) === 'LaunchRequest';
     },
     handle(handlerInput) {
-        const speakOutput = 'Welcome, you can say Hello or Help. Which would you like to try?';
+        const speakOutput = handlerInput.t('WELCOME_MSG');
         return handlerInput.responseBuilder
             .speak(speakOutput)
             .reprompt(speakOutput)
@@ -21,8 +23,8 @@ const HelloWorldIntentHandler = {
             && Alexa.getIntentName(handlerInput.requestEnvelope) === 'HelloWorldIntent';
     },
     handle(handlerInput) {
-        const speakOutput = 'Hello World!';
-        return handlerInput.responseBuilder
+      const speakOutput = handlerInput.t('HELLO_MSG');
+      return handlerInput.responseBuilder
             .speak(speakOutput)
             //.reprompt('add a reprompt if you want to keep the session open for the user to respond')
             .getResponse();
@@ -34,7 +36,7 @@ const HelpIntentHandler = {
             && Alexa.getIntentName(handlerInput.requestEnvelope) === 'AMAZON.HelpIntent';
     },
     handle(handlerInput) {
-        const speakOutput = 'You can say hello to me! How can I help?';
+        const speakOutput = handlerInput.t('HELP_MSG');
 
         return handlerInput.responseBuilder
             .speak(speakOutput)
@@ -49,12 +51,31 @@ const CancelAndStopIntentHandler = {
                 || Alexa.getIntentName(handlerInput.requestEnvelope) === 'AMAZON.StopIntent');
     },
     handle(handlerInput) {
-        const speakOutput = 'Goodbye!';
+        const speakOutput = handlerInput.t('GOODBYE_MSG');
         return handlerInput.responseBuilder
             .speak(speakOutput)
             .getResponse();
     }
 };
+
+// FallbackIntent triggers when a customer says something that doesn’t map to any intents in your skill
+// It must also be defined in the language model (if the locale supports it)
+// This handler can be safely added but will be ingnored in locales that do not support it yet 
+const FallbackIntentHandler = {
+  canHandle(handlerInput) {
+      return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest'
+          && Alexa.getIntentName(handlerInput.requestEnvelope) === 'AMAZON.FallbackIntent';
+  },
+  handle(handlerInput) {
+      const speakOutput = handlerInput.t('FALLBACK_MSG');
+
+      return handlerInput.responseBuilder
+          .speak(speakOutput)
+          .reprompt(speakOutput)
+          .getResponse();
+  }
+};
+
 const SessionEndedRequestHandler = {
     canHandle(handlerInput) {
         return Alexa.getRequestType(handlerInput.requestEnvelope) === 'SessionEndedRequest';
@@ -75,7 +96,7 @@ const IntentReflectorHandler = {
     },
     handle(handlerInput) {
         const intentName = Alexa.getIntentName(handlerInput.requestEnvelope);
-        const speakOutput = `You just triggered ${intentName}`;
+        const speakOutput = handlerInput.t('REFLECTOR_MSG', {intentName: intentName});
 
         return handlerInput.responseBuilder
             .speak(speakOutput)
@@ -93,7 +114,7 @@ const ErrorHandler = {
     },
     handle(handlerInput, error) {
         console.log(`~~~~ Error handled: ${error.stack}`);
-        const speakOutput = `Sorry, I had trouble doing what you asked. Please try again.`;
+        const speakOutput = handlerInput.t('ERROR_MSG');
 
         return handlerInput.responseBuilder
             .speak(speakOutput)
@@ -102,6 +123,17 @@ const ErrorHandler = {
     }
 };
 
+const LocalisationRequestInterceptor = {
+  process(handlerInput) {
+      i18n.init({
+          lng: Alexa.getLocale(handlerInput.requestEnvelope),
+          resources: languageStrings
+      }).then((t) => {
+          handlerInput.t = (...args) => t(...args);
+      });
+  }
+};
+
 // The SkillBuilder acts as the entry point for your skill, routing all request and response
 // payloads to the handlers above. Make sure any new handlers or interceptors you've
 // defined are included below. The order matters - they're processed top to bottom.
@@ -111,10 +143,14 @@ exports.handler = Alexa.SkillBuilders.custom()
         HelloWorldIntentHandler,
         HelpIntentHandler,
         CancelAndStopIntentHandler,
+        FallbackIntentHandler,
         SessionEndedRequestHandler,
         IntentReflectorHandler, // make sure IntentReflectorHandler is last so it doesn't override your custom intent handlers
         ) 
     .addErrorHandlers(
         ErrorHandler,
         )
+    .addRequestInterceptors(
+        LocalisationRequestInterceptor
+        )
     .lambda();

lambda/languageStrings.js

@@ -0,0 +1,20 @@
+/* *
+ * We create a language strings object containing all of our strings.
+ * The keys for each string will then be referenced in our code, e.g. handlerInput.t('WELCOME_MSG').
+ * The localisation interceptor in index.js will automatically choose the strings
+ * that match the request's locale.
+ * */
+
+module.exports = {
+    en: {
+        translation: {
+            WELCOME_MSG: 'Welcome, you can say Hello or Help. Which would you like to try?',
+            HELLO_MSG: 'Hello World!',
+            HELP_MSG: 'You can say hello to me! How can I help?',
+            GOODBYE_MSG: 'Goodbye!',
+            REFLECTOR_MSG: 'You just triggered {{intentName}}',
+            FALLBACK_MSG: 'Sorry, I don\'t know about that. Please try again.',
+            ERROR_MSG: 'Sorry, I had trouble doing what you asked. Please try again.'
+        }
+    }
+}

lambda/package.json

@@ -11,6 +11,7 @@
     "dependencies": {
       "ask-sdk-core": "^2.6.0",
       "ask-sdk-model": "^1.18.0",
-      "aws-sdk": "^2.326.0"
+      "aws-sdk": "^2.326.0",
+      "i18next": "^15.0.5"
     }
   }