I am trying to create a sendNotification function by using node.js and firebase function but unfortunately I am currently stuck. I never got a notification from the sender and when I look to Firebase function logs, I saw an error says
ReferenceError: context is not defined
at exports.sendNotification.functions.database.ref.onWrite.event (/user_code/index.js:9:32)
at Object.<anonymous> (/user_code/node_modules/firebase-functions/lib/cloud-functions.js:112:27)
at next (native)
at /user_code/node_modules/firebase-functions/lib/cloud-functions.js:28:71
at __awaiter (/user_code/node_modules/firebase-functions/lib/cloud-functions.js:24:12)
at cloudFunction (/user_code/node_modules/firebase-functions/lib/cloud-functions.js:82:36)
at /var/tmp/worker/worker.js:700:26
at process._tickDomainCallback (internal/process/next_tick.js:135:7)
this is my code index.js code
`const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
exports.sendNotification = functions.database.ref('notifications/{user_id}').onWrite(event => {
const user_id = context.params.user_id;
const notification_id = context.params.notification_id;
console.log('We have notification from: ', user_id);
if (!event.val()) {
return console.log('A Notification has been deleted from the database: ', notification_id);
}
const fromUser = admin.database().ref(`/Users/${user_id}/device_token`).once('value');
return fromUser.then(result => {
const token_id = result.val();
const payload = {
notification: {
title: "Friend Request",
body: "You've received a Friend Request",
icon: "default"
}
};
return admin.messaging().sendToDevice(token_id , payload).then(response => {
console.log('This was the notification feature');
});
});
});
I don't know where is the error here can someone tell me where is the error and how can I resolve it?
I am trying to create a sendNotification function by using node.js and firebase function but unfortunately I am currently stuck. I never got a notification from the sender and when I look to Firebase function logs, I saw an error says
ReferenceError: context is not defined
at exports.sendNotification.functions.database.ref.onWrite.event (/user_code/index.js:9:32)
at Object.<anonymous> (/user_code/node_modules/firebase-functions/lib/cloud-functions.js:112:27)
at next (native)
at /user_code/node_modules/firebase-functions/lib/cloud-functions.js:28:71
at __awaiter (/user_code/node_modules/firebase-functions/lib/cloud-functions.js:24:12)
at cloudFunction (/user_code/node_modules/firebase-functions/lib/cloud-functions.js:82:36)
at /var/tmp/worker/worker.js:700:26
at process._tickDomainCallback (internal/process/next_tick.js:135:7)
this is my code index.js code
`const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
exports.sendNotification = functions.database.ref('notifications/{user_id}').onWrite(event => {
const user_id = context.params.user_id;
const notification_id = context.params.notification_id;
console.log('We have notification from: ', user_id);
if (!event.val()) {
return console.log('A Notification has been deleted from the database: ', notification_id);
}
const fromUser = admin.database().ref(`/Users/${user_id}/device_token`).once('value');
return fromUser.then(result => {
const token_id = result.val();
const payload = {
notification: {
title: "Friend Request",
body: "You've received a Friend Request",
icon: "default"
}
};
return admin.messaging().sendToDevice(token_id , payload).then(response => {
console.log('This was the notification feature');
});
});
});
I don't know where is the error here can someone tell me where is the error and how can I resolve it?
Share Improve this question edited Apr 17, 2018 at 10:08 Peter Haddad 80.9k25 gold badges145 silver badges146 bronze badges asked Apr 17, 2018 at 5:21 user8724610user8724610 3-
1
It's exactly as the error says - you never define
context
before you use it...? – CertainPerformance Commented Apr 17, 2018 at 5:22 - Okay, so how can I define the context here? – user8724610 Commented Apr 17, 2018 at 5:24
-
I don't know, it's your app - you seem to have something in mind when you access its
.params.user_id
. Figure out what that object is, and assign it tocontext
before you use it – CertainPerformance Commented Apr 17, 2018 at 5:26
2 Answers
Reset to default 2Change it to this:
exports.sendNotification = functions.database.ref('notifications/{user_id}').onWrite((change,context) => {
const user_id = context.params.user_id;
});
onWrite
has two parameters change
and context
. You use context
to access the wildcards example user_id
.
more info here:
https://firebase.google./docs/functions/beta-v1-diff
I managed to solved my own problem by the help of @PeterHaddad. I read the link that he post and I change some of my code. Here it is
const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
exports.sendNotification = functions.database.ref('notifications/{user_id}').onWrite((change, context) => {
const user_id = context.params.user_id;
const notification_id = context.params.notification_id;
console.log('We have notification from: ', user_id);
if (!change.after.val()) {
return console.log('A Notification has been deleted from the database: ', notification_id);
}
const fromUser = admin.database().ref(`/Users/${user_id}/device_token`).once('value');
return fromUser.then(result => {
const token_id = result.val();
const payload = {
notification: {
title: "Friend Request",
body: "You've received a Friend Request",
icon: "default"
}
};
return admin.messaging().sendToDevice(token_id , payload).then(response => {
console.log('This was the notification feature');
});
});
});