Firebase Functions - ReferenceError: event is not defined

Question

I'm trying to do a simple notification function but every time i fire the function i get ERROR

TypeError: Cannot read property 'params' of undefined at exports.sendNotification.functions.database.ref.onWrite (/user_code/index.js:23:32) at cloudFunctionNewSignature (/user_code/node_modules/firebase-functions/lib/cloud-functions.js:105:23) at cloudFunction (/user_code/node_modules/firebase-functions/lib/cloud-functions.js:135:20) at /var/tmp/worker/worker.js:758:24 at process._tickDomainCallback (internal/process/next_tick.js:135:7)

Or i get the error

TypeError: Cannot read property 'user_id' of undefined

I got an answer from here

but i't didn't help at all , and i can't find the problem . this is my code

'use strict'
const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp();

exports.sendNotification = functions.database.ref('/notifications/{user_id}/{notification_id}').onWrite((change,context) => {

const user_id = event.params.user_id;
const notification_id = event.params.notification_id;

console.log('We have a notification from : ', user_id);

if(!context.data.val()){

return console.log('A Notification has been deleted from the database : ', 
notification_id);

}

const fromUser =admin.database().ref(`/notifications/${user_id}/${notification_id}`).once('value');

return fromUser.then(fromUserResult => {

const from_user_id = fromUserResult.val().from;

console.log('You have new notification from  : ', from_user_id);

const userQuery = admin.database().ref(`Users/${from_user_id}/name`).once('value');
const deviceToken = admin.database().ref(`/Users/${user_id}/device_token`).once('value');

return Promise.all([userQuery, deviceToken]).then(result => {

  const userName = result[0].val();
  const token_id = result[1].val();

  const payload = {
    notification: {
      title : "New Friend Request",
      body: `${userName} has sent you request`,
      icon: "default",
      click_action : "none"
    },
    data : {
      from_user_id : from_user_id
    }
  };

  return admin.messaging().sendToDevice(token_id, payload).then(response => {

    return console.log('This was the notification Feature');

     });

   });

  });

});

Doug Stevenson Doug Stevenson · Accepted Answer · 2018-11-24T12:32:12

You never defined event, so it's undefined. You're trying to access a property on an undefined variable. Did you mean context.params.user_id?

(You're probably using an out of date tutorial. I see bad "sendNotification" functions like this all the time on Stack Overflow. Let the author know.)

Firebase Functions - ReferenceError: event is not defined

1 Answers