This is not a problematic question, it was asked because just wanted to know what's actually going on behind it, I can't find an answer in any documentation.
When i open the app without internet it shows the data from firebase, i try to restart then it also shows, i try to clear the cache but it shows the data like it shows from the local database, Why is this happening, is there a built-in local storage or something in Firebase Flutter?
Firestore SDKs cache any data that they've recently seen, as well as any pending writes from the local client that haven't been synchronized to the server yet. On mobile clients (iOS and Android) this cache is enabled by default, while on web you can enable it with an API call.
For more on this, see the Firebase documentation on accessing Firestore data while you're offline.
Related
This question already has an answer here:
Does Firebase JavaScript API catch-up with server when re-connected
(1 answer)
Closed last year.
I have a web app that uses a Realtime Database to store data. If I go offline while the database is connected, make changes, and reconnect, everything works as intended. However, I'm trying to make my web app work as a PWA. Right now, the database only works offline if the page goes online while being used. If you close the app fully while offline and open the app, it won't load.
I see that Cloud Firestore for web has the enableIndexedDbPersistence() method, which appears to do what I want, although obviously since it's for a different service I can't use it. I also see that Realtime Database for Android has FirebaseDatabase.getInstance().setPersistenceEnabled(true), but since its for Android I can't use it for a web app.
Is there a way to enable this functionality?
Firebase Realtime Database only supports disk persistence in its Android and iOS SDKs. There is no disk persistence in the JavaScript SDK for Firebase Realtime Database.
Also see:
Does Firebase JavaScript API catch-up with server when re-connected
I have no code but only a special question regarding Cloud Firestorage by Google.
Im using currently a listener for my Firestorage within my react-native-app which I also use expo for.
I know that as long as I stay in the app and tab out of the window, all data downloaded by the listener is getting stored in a temporary cache so when I come back to the screen with the listener, the listener doesnt need to download all data again but rather the missing sample.
My question would be: Does this also apply if I close the app entirely, for example for multiple days so that my token for authentification expires and I need to log myself in again into the app or rather into my Firebase?
(I want to prevent downloading all data the listener points to only because I restarted the app.)
As explained here the firestore persistance for the web is disk persistance so it survies App and devices restarts. Multiple days should also be fine.
I have a Web App tha is using firestore and very heavily offline capabilities. We never had issues with that.
I was able to configure the Firestore database in Firebase with my flutter app and also create and read documents from my collection but when I go to Firestore console I don't see the created data, also when I creat data manually I am unable to see it in my application.
I am using the test mode which means any user can read or write.
I hope someone can help me with this puzzle.
Thanks!!!
It sounds like the device/emulator that you are running on is not connected to the internet, or at least not to the Firestore servers. In that case, the client writes all local changes into a local database, waiting to send them to the server when it gets a connection. So the local app will work, but won't be able to synchronize its local cache with the database servers.
You might want to check the connection on your device, and any proxies that might exist between your app and the Firestore servers.
I'm just getting started with the Firebase ecosystem and doing some investigating before committing to a GCloud database implementation (Datastore vs. Firestore). My target client is Web/browser and my backend services will be in AppEngine.
Tinkering with the cloud messaging quickstart example, it seems that FCM doesn't work in several scenarios (incognito mode, Safari, if permission blocked). However, the friendly chat demo that uses realtime db updates does appear to work in these scenarios.
High level could anyone explain why?
My goal is to subscribe to events for the client to update state, etc without the use of polling. It seems overkill to put these into firestore just to bypass the notifications permission requirements. Any insight is appreciated. These events could be dispatched from several different backend services and are not exclusively bound to db records.
Update
For what I wanted to do, I was able to simply use Firestore and had no needs that targeted specific devices that merited using FCM. Firestore came out of beta since I posted this question and works well for live subscribing to queries that update local state, which is ultimately what I needed to do.
The FCM client works on the promise that it can identify your browser, even when the page is not open. So it needs to persistently be able to identify the browser. It uses an Instance Token for that, which I assume it persists in the local storage of your browser. And since an incognito window has its own local storage, it becomes a separate instance ID.
The Firebase Realtime Database itself does not persist any information about the instance. Instead you pass in all the necessary information when you initialize the FirebaseApp instance, and then get a DatabaseReference. Since the incognito window runs the same code, it's accessing the same information in the database, and thus seeing the same result.
Note that this would be different if you use Firebase Authentication in combination with the Realtime Database. Auth will persist the user token to local storage, so that won't be shared with the incognito window.
I am working on react-native with firestore and creating an offline application. The data should be stored in firestore when there is an healthy internet connection. If not, it should be stored in cache.
In firestore, there is an Enable offline data where the data can be stored offline. But, I didn't understand what and where exactly I've to write into that.
So anyone can help me out?
Thanks in advance
in your firebase file immediately after
firebase.initializeApp(firebbaseConfig)
firebase.firestore()
.enable persistence()
.catch(err => console.log(err)
The documentation for offline persistence states:
To use offline persistence, you don't need to make any changes to the
code that you use to access Cloud Firestore data. With offline
persistence enabled, the Cloud Firestore client library automatically
manages online and offline data access and synchronizes local data
when the device is back online.
So, you don't have to do anything to take this default behavior.
Firestore maintains copy of data locally, so even it writes data in offline and fetch it.
If you want to enable firestore persistence in your react native app, just copy paste the code from documentation to App.js, I am using the same and it is working fine.