Unable to drag data to Firebase from Alexa Skill hosted on AWS Lambda

Question

I have a database in Firebase to which I am trying to write some data from my Alexa Skill. The Node.js code for this skill is inside the AWS Lambda function, and when this code is executed, I want to push some data to Firebase.

I tested the code that connects to Firebase outside of Lambda and pushes it, and works exactly as expected. Below is the code:

var firebase = require('firebase'); firebase.initializeApp({ databaseURL: 'https://myapp.firebaseio.com', serviceAccount: './myapp.json', }); var cart = firebase.database().ref('/cart'); console.log(cart); cart.push( { item: 'apples', quantity: '1', amount: '0' }, function(error) { if (error) { console.log("Data could not be saved." + error); } else { console.log("Data saved successfully."); } }); 

The same code does not click anything on the database instance when executed from the Lambda function. I read on the Internet that the Lambda timeout limit could be the reason for this, so I increased the timeout limit to a minute and it still doesn't work as expected. I also tried using the Firebase REST API instead of my Node.js SDK, and that didn't work either. What is the correct way to transfer data to Firebase from AWS Lambda?

Answer 1

I think I know why this is happening, I had a similar problem and this is what I did.

If you want to write some date to your database, you need to make sure that you do not call this.emit (*****) until you are done. As soon as you return a response to the user, the stream closes and your information is not saved.

The easiest way to solve this problem is to return a response to the user after confirming that the information has been saved.

In the case of Firebase, something like this:

 function writeUserData(userId) { // Get a key for a new Post. var userKey = db.ref('users/').push().key; var reference = db.ref('users/' + userKey).set({ user: userId }); reference.then(() => { alexa.emit(':ask', "Works"); }, (err) => { alexa.emit(':ask', "Does not work"); }); 

}

I could not save anything until I began to do so.

Hope this helps.

Answer 2

I came across this too, and the only way I figured out how to make it work is to defer the lambda callback function in the handler. Try this and let me know if that works.

 var firebase = require('firebase'); firebase.initializeApp({ databaseURL: 'https://myapp.firebaseio.com', serviceAccount: './myapp.json', }); exports.handler = (event, context, callback) => { var cart = firebase.database().ref('/cart'); console.log(cart); cart.push( { item: 'apples', quantity: '1', amount: '0' setTimeout(()=>{ callback(null, 'success'); },2000); }, function(error) { if (error) { console.log("Data could not be saved." + error); setTimeout(()=>{ callback(error); },2000); } else { console.log("Data saved successfully."); setTimeout(()=>{ callback(null, 'success'); },2000); } }); }