How to handle Firebase.Database.FirebaseException raised by Firebase.Database.Streaming.FirebaseSubscription`1.<ReceiveThread>d__14.MoveNext()

[ywlau]

subscription codes:

private void init()
{
try
{
var ref= firebase.Child("Infos/updates");
var observable = ref.AsObservable();
subscription = observable
.Where(f => !string.IsNullOrEmpty(f.Key))
.Subscribe(f => processInfoUpdate(f.Object));
}
catch (Exception ex)
{
}
}

private void processInfoUpdate(InfoUpdate update)
{
try
{
//process update
}
catch (Exception ex)
{
}
}

The code was running ok initially; after sometime, the following exception is thrown.
Tried putting the relevant codes in try catch block, but doesn't help.
What's the best way to handle this exception ?

Firebase.Database.FirebaseException: Exception occured while processing the request.
Url: https://myproject.firebaseio.com/Infos/updates/.json?auth=verylongauthstring
Request Data:
Response: ---> System.Net.Http.HttpRequestException: Response status code does not indicate success: 401 (Unauthorized).
at System.Net.Http.HttpResponseMessage.EnsureSuccessStatusCode()
at Firebase.Database.Streaming.FirebaseSubscription1.<ReceiveThread>d__14.MoveNext() --- End of inner exception stack trace --- at System.Reactive.PlatformServices.DefaultExceptionServices.Rethrow(Exception exception) at System.Reactive.Stubs.<>c.<.cctor>b__2_1(Exception ex) at System.Reactive.AnonymousSafeObserver1.OnError(Exception error)
at System.Reactive.Linq.ObservableImpl.Where1._.OnError(Exception error) at System.Reactive.AutoDetachObserver1.OnErrorCore(Exception exception)
at System.Reactive.ObserverBase1.OnError(Exception error) at Firebase.Database.Streaming.FirebaseSubscription1.d__14.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.AsyncMethodBuilderCore.<>c.b__6_1(Object state)
at System.Threading.QueueUserWorkItemCallback.WaitCallback_Context(Object state)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
at System.Threading.ThreadPoolWorkQueue.Dispatch()
at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback()

[bezysoftware]

Response status code does not indicate success: 401 (Unauthorized).

This means the auth token is not valid

[ywlau]

how should i handle it when the auth token is expired (the code was running fine initially) ?

btw, AuthLink_FirebaseAuthRefreshed event is not raised.

Thanks

[bezysoftware]

Refreshing token is described here: step-up-labs/firebase-authentication-dotnet#14 (comment)

[ywlau]

incorporated the refreshing token strategy and ran the app. twice; with subscription and without.

auth.FirebaseAuthRefreshed is not called in both runs and Firebase.Database.FirebaseException is thrown only if subscription is included.

I'm using FirebaseAuthentication.net v3.0.5 and FirebaseDatabase.net v3.0.0

private void init()
{
	authProvider = new FirebaseAuthProvider(new FirebaseConfig(FirebaseAppKey));
	auth = Task.Run(() => authProvider.SignInWithEmailAndPasswordAsync("myemail", "mypassword")).Result;
	auth.FirebaseAuthRefreshed += AuthLink_FirebaseAuthRefreshed;

        ......
}


private void AuthLink_FirebaseAuthRefreshed(object sender, FirebaseAuthEventArgs e)
{
	auth = Task.Run(() => auth.GetFreshAuthAsync()).Result;

	firebase = new FirebaseClient(
	FirebaseAppUri,
	new FirebaseOptions
	{
		AuthTokenAsyncFactory = () => Task.FromResult(auth.FirebaseToken)
	});
}

[ywlau]

from Firebase.Auth source code; it seems we need to call the following method to trigger the auth.FirebaseAuthRefreshed event, right ?

var freshAuth = auth.GetFreshAuthAsync().Result;

if so, what's the best practice; call regularly in timer ?

Thank You.

[bezysoftware]

Use it in FirebaseOptions:

new FirebaseOptions
	{
		AuthTokenAsyncFactory = async () => (await auth.GetFreshAuthAsync()).FirebaseToken
	});

FirebaseAuthRefreshed event is raised to give you a chance to save the token to storage & load it upon application restart (e.g. user logs in with facebook and the token is kept so he doesn't need to login again after app restart)

[ywlau]

just some feedback; in addition of refreshing token strategy, i also added err handling in subscription to handle all other potential exception gracefully.

private void init()
{
try
{
   var ref= firebase.Child("Infos/updates");
   var observable = ref.AsObservable();
   subscription = observable
      .Where(f => !string.IsNullOrEmpty(f.Key))
      .Subscribe(f => processInfoUpdate(f.Object),
         ex =>processInfoErr(),
         () => processInfoComplete();
}
catch (Exception ex)
{
}
}

thank you again for the good work

btw, where can i find the latest source code of FirebaseDatabase.net project (Nuget v3.0.5 and Github v.2.0.0) ?

[bezysoftware]

What do you mean where you can find sources for the nuget? They are all here on github: https://github.com/step-up-labs/firebase-database-dotnet

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

Closing the issue due to inactivity. Feel free to re-open