FireStore listener as a service stop working after a day

Version: Google.Cloud.Firestore-1.0.0-beta13

Guys, I am having some issues with FireStore real time updates. I have deployed a web app to Azure Web Site. On a start up, this application subscribes to the updates in the FireStore users table. `

        GoogleCredential googleCredential = googleCredential = GoogleCredential.FromJson(JsonConvert.SerializeObject(secret));
        var channel = new Grpc.Core.Channel(FirestoreClient.DefaultEndpoint.Host,
            googleCredential.ToChannelCredentials());

        FirestoreClient client = FirestoreClient.Create(channel);
        FirestoreDb db = FirestoreDb.Create(projectId: "myproject-2018", client: client);

        CollectionReference collection = db.Collection("users");


        FirestoreChangeListener listener = collection.Listen(async querySnapshot =>
        {
        })

`

All works perfect, but after a couple hours, or sometimes days, it just stop receiving updates without any errors. Is there any way for me to debug it to understand why?

[jskeet]

I saw a failure yesterday and this morning which was unrelated (and which I’ve asked about internally). I could merge my expected fix in and do another release today; I don’t believe it’s harmful, and it would let others test over Christmas.

[pauloevpr]

I have a similar issue. I am running an Asp.Net Core 2.1 Web API on Google Cloud App Engine. The FirestoreListener stops working eventually. I can’t say it is precisely after 24 hours. It seems just random.

From my analysis so far, it seems to be an issue with Firestore backend rather than the Firestore .NET SDK. Firestore randomly fails when reading/writing documents. It is not just about the listeners.

For example. Yesterday my Asp.Net Core Web API had the following exception when getting a document snapshot:

Grpc.Core.RpcException: Status(StatusCode=PermissionDenied, Detail=“Missing or insufficient permissions.”)

I have seen this at least once every month.

That is not the only one. I also have this one randomly once in a while when reading documents:

Grpc.Core.RpcException: Status(StatusCode=Unavailable, Detail=“The datastore operation timed out, or the data was temporarily unavailable.”)

My conclusion is that, as a beta product, it is possible that Firestore backend randomly fails to serve requests for whatever reason.

For the specific listener issue, my workaround is to have a function triggered by a timer which will restore the listener as required.