Node.js-Google-Assistant

Simple Google Assistant Development using Node.js

Introduction

Google provides many facilities with Google Assistant as easy-integrated with platforms, developing with different languages, engaging voice and text-based conversational.

There are three base platforms to develop and deploy assistant,

• Dialogflow (Platform that Creating Chatbot and Setting "Intent ,Entities")
• Actions On Google (Manage and connect your services and assistant settings)
• Firebase (Assistant Functions deploy on Firebase to get request)(Optional).

This project and documentation contains informations about Google Assistant Development Cycle.

Dialogflow

Dialogflow is a platform to create chatbot and setting Intent and Entities. With Natural Language Processing (NLP) algoritm in Dialoglow , chatbot can understand easily what do you want to say. Firstly , let's explain Dialogflow concepts with images and more details. Login Dialogflow with your google account and then click the create agent. After sets the assistant, you will see this screen:

Intents are simple messaging objects that describe how to do something You can find here. There are two Default Intent in chatbot, "Default Welcome Intent" and "Default Fallback Intent". I can explain easily Intents and Intents feature with simple example.

Assistant and user play a game each other, Assistant keeps a number between 0-10 and user tries to guess with three rights. Assistant catches the request with "guess_number" intent. Add possible messages to the "Training phrases" in "guess_number" intent like "My guess number is 5" or "number is 3".

When the user make a mistake guess, assistant should decrease the number of rights so to do that, assistant uses User storage. There is simple piece of code example ,

app.intent('Default Welcome Intent', conv => {
  conv.user.storage.number_of_rights=5;
  conv.ask(`Welcome! You have ${conv.user.storage.number_of_rights} rights to guess my number. Say a number.`);
});

How can the Assistant catch the number in request ? Assistant uses entities to catch specific value in the request. For this example, assistant needs a number and there is already sys.number entity defined by default. Entities seems as,

To reach these values in backend, conv.parameters.PARAMATER_NAME is used.

app.intent('guess_number', conv => {
 console.log('guess : ',conv.parameters.number);
  if(conv.parameters.number==number){
     conv.ask('That is right. Thanks');
     }
......

After adding intent , entities and necessary code blocks; every wrong guess, assistant decrease the conv.user.storage.number_of_rights.

There are two ways to deploy a assistant. If you click Fulfillment tab, you can see this screen.

Inline editor is online development enviroment. Just type your code and deploy. If you have a web service that listen to request from dialogflow, you can type service url and dialogflow can speak to your service. For this example, firebase functions are used so our assistant backend deployed on firebase.

Actions On Google

Actions On Google is a developer platform that extends asisstant's functionalities, deploy assistant as a product for Alpha (up to 20 users), Beta (up to 200 users) or Production ,and sets general settings of assistant. At the same time, there is a simulator to test assistant on this platform. Another important thing in this platform is "Account Linking" and I will explain in another project.

Firebase

Firebase is a development enviroment that has many services as Real Time Database,Hosting,Cloud Messaging,Storage,Hosting, Functions. In this project, Firebase Functions is used to deploy assistant. Let's explain deploy assistant to the firebase functions.

Clone this project, then open command line and install firebase tools with this code.

npm i firebase-tools

Use this command to login your firebase account.

firebase login

Setup the Firebase feautres, execute this command, then select the functions with SPACEBAR.

firebase init

Deploy project and use Firebase Console to manage your functions.

firebase deploy

To connect your assistant and firebase function, just copy and paste your functions deployed address to the assistant webhook.

Every thing is done, now your assistant is ready.