Firebase Cloud Functions在Create上获取实时数据库上的数据 [英] Firebase Cloud Functions get data on real time database onCreate
问题描述
const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp();
exports.sendNotification = functions.database.ref('/messages/diyetisyen/{uname}/{msgid}/message')
.onCreate((snapshot, context) => {
let message = snapshot.val();
let uname = context.params.uname;
let root = snapshot.ref.root;
let token = root.child('/users/' + uname + '/token').ref.token;
let payload = {
data: {
custom_notification: JSON.stringify({
body: message + '',
title: 'aaaa'
})
}
};
let options = { priority: "high" };
return admin
.messaging()
.sendToDevice(token, payload, options);
});
我无法在/users/{uname}/token->值上获得令牌.
i cant get token on /users/{uname}/token -> value.
错误:提供给sendToDevice()的注册令牌必须是非空字符串或非空数组.在FirebaseMessagingError.FirebaseError [作为构造函数](/srv/node_modules/firebase-admin/lib/utils/error.js:42:28)在FirebaseMessagingError.PrefixedFirebaseError [作为构造函数](/srv/node_modules/firebase-admin/lib/utils/error.js:88:28)在新的FirebaseMessagingError(/srv/node_modules/firebase-admin/lib/utils/error.js:253:16)在Messaging.validateRegistrationTokensType(/srv/node_modules/firebase-admin/lib/messaging/messaging.js:911:19)在Messaging.sendToDevice(/srv/node_modules/firebase-admin/lib/messaging/messaging.js:532:14)在exports.sendNotification.functions.database.ref.onCreate(/srv/index.js:28:5)在cloudFunctionNewSignature(/srv/node_modules/firebase-functions/lib/cloud-functions.js:120:23)在/worker/worker.js:825:24在在process._tickDomainCallback(internal/process/next_tick.js:229:7)
Error: Registration token(s) provided to sendToDevice() must be a non-empty string or a non-empty array. at FirebaseMessagingError.FirebaseError [as constructor] (/srv/node_modules/firebase-admin/lib/utils/error.js:42:28) at FirebaseMessagingError.PrefixedFirebaseError [as constructor] (/srv/node_modules/firebase-admin/lib/utils/error.js:88:28) at new FirebaseMessagingError (/srv/node_modules/firebase-admin/lib/utils/error.js:253:16) at Messaging.validateRegistrationTokensType (/srv/node_modules/firebase-admin/lib/messaging/messaging.js:911:19) at Messaging.sendToDevice (/srv/node_modules/firebase-admin/lib/messaging/messaging.js:532:14) at exports.sendNotification.functions.database.ref.onCreate (/srv/index.js:28:5) at cloudFunctionNewSignature (/srv/node_modules/firebase-functions/lib/cloud-functions.js:120:23) at /worker/worker.js:825:24 at at process._tickDomainCallback (internal/process/next_tick.js:229:7)
推荐答案
您不能通过这样做获得数据库节点的值
You cannot get the value of a database node by doing
let token = root.child('/users/' + uname + '/token').ref.token;
您需要使用 <
You need to query the database with the once()
method of the Reference
, which is asynchronous.
这意味着您必须按以下步骤修改代码:
It means that you have to modify your code as follows:
exports.sendNotification = functions.database.ref('/messages/diyetisyen/{uname}/{msgid}/message')
.onCreate((snapshot, context) => {
let message = snapshot.val();
let uname = context.params.uname;
let root = snapshot.ref.root;
let tokenRef = root.child('/users/' + uname + '/token').ref;
let payload = {
data: {
custom_notification: JSON.stringify({
body: message + '',
title: 'aaaa'
})
}
};
let options = { priority: "high" };
return tokenRef.once('value')
.then(dataSnapshot => {
const data = dataSnapshot.val();
const token = data.token; //Here I make the assumption the token is at '/users/' + uname + '/token/token'. You may adapt it as required
return admin
.messaging()
.sendToDevice(token, payload, options);
});
});
这篇关于Firebase Cloud Functions在Create上获取实时数据库上的数据的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!