firebase-realtime-database

问题 So I got one Screen with the Firebase configuration and one which should call the data. I'd like to have up to date Information. As of now I have the following code: export const firebaseFetchProfileItem = (category) => { var snap; database .ref("users/" + authentification.currentUser.uid + "/profile/" + category) .on("value", function (snapshot) { snapshot.val() ? (snap = snapshot.val()) : undefined; }), function (error) { log.error(error); }; return snap; }; It works "okayish", since it

问题 I want to display multiple images into a screen. My database tree looks like this: I am also able to load the object through snapshot.val() and this is how it looks like in the console while running: Object { "4aae-47bb-e0f7-36e2-7e66": Object { "author": "edm9AAbPpFUWrO9HDXfV442QzSE2", "caption": "Test 1", "photo": Object { "2e30-b971-5c62-0b68-837f": Object { "url": "https://firebasestorage.googleapis.com/v0/b/...someURL...", }, "38de-15f2-bb7b-b58d-e863": Object { "url": "https:/

问题 I have a structure in which users are registering for events, and the registered events are stored as the following: I am trying to access the registeredEvents and display the children on a table view. So far, I have done this: override func viewDidLoad() { super.viewDidLoad() let id = Auth.auth().currentUser?.uid let ref = Database.database().reference() ref.child("users").child(id!).child("registeredEvents").observeSingleEvent(of: .value, with: { snapshot in print(snapshot.childrenCount)

问题 I want to send a notification to all users who are confirmed guests when the object confirmedGuests is created in the Firebase Realtime Database. So, I first create an array of all the users from confirmedGuests object. Then, I iterate through all these users and push their deviceTokens to an array of deviceTokens. The array allDeviceTokens is expected to be the array of device tokens of all users in confirmedGuests. However, when confirmedGuests object is created, the function returns an

问题 I made a android chat app and setup the automated notifications using functions in firebase, everything is working fine but when i send a message notifications won't come Here are the logs in firebase function - Here is the index.js file - 'use strict' const functions = require('firebase-functions'); const admin = require('firebase-admin'); admin.initializeApp(functions.config().firebase); exports.sendNotification = functions.database.ref('/Notifications/{user_id}/{notification_id}').onWrite

问题 Due to problems using a Realtime Database emulator for development in Flutter ( see How do I connect to my local Realtime Database emulator in my Flutter app? ), I am now simply using my non-local Realtime Database for development. However, I am also using Cloud Functions, and I have created a Functions emulator. I tried the following to connect to it, based on this StackOverflow-answer: const functions = require("firebase-functions"); const admin = require("firebase-admin"); functions.config

问题 This question already has an answer here : Firebase query if child of child contains a value (1 answer) Closed 1 year ago . I'm new to react-native and firebase, and I am building an app. I stumble upon a problem using "array" in firebase (i know that firebase doesn't work with array), but I want to know if there is some way to retrieve this data. This is the data I have in the server, and I want to get all the purchases that have the product "id" (in red) I tried to use the code below and

问题 I have a collection in firebase real time database that is a pool of codes that can be used once per 'store'. I need to search for an unused code, then mark it reserved by a store in an atomic fashion. The problem is I can't figure out how to do a transactional search and update in firebase, and the unused code is being 'used' multiple times until it gets updated. const getUnusedCode = (storeID) => { const codeRef = rtdb.ref('codes'); return codeRef .orderByChild(storeID) .equalTo(null)

问题 I have 50 realtime firebase database instances which are all identical. Is it possible to get all my firebase functions to trigger on all instances, rather than just the default instance? I know you can do this exports.myWriteFunction = functions.database.instance('my-secondary-db').ref('path/to/data').onUpdate((snap, context) => { ... }) But I really want to run this function on every instance... 回答1: There is no way to automatically associate a function with all database instances. You will

问题 I´m searching the best way to migrate Firebase Realtime Database Data to Cloud Firestore for a json database with many nested rows. Example: I found nothing that could help me. For what I need the migration is the new offline functionality of the Cloud Firestore. I´m using Ionic3 (Angular5) 回答1: Actually there's no standard way to migrate from Firebase Realtime Database to Cloud Firestore, because every application or project has is unique. You have to implement your own way of migrating to