Firebase实时数据库超时

Question

I have implemented a simple timeout system for requests to my Realtime Database.

private void makeRequestWithTimeout(final int timeout, final DatabaseReference reference, final OnTimeoutRequestListener listener) {

    Thread thread = new Thread() {
        boolean connected = false;
        boolean exited = false;

        @Override
        public void run() {

            reference.addListenerForSingleValueEvent(new ValueEventListener() {
                @Override
                public void onDataChange(DataSnapshot dataSnapshot) {
                    if (!exited) {
                        listener.onSuccess(dataSnapshot);
                        connected = true;
                    }
                }

                @Override
                public void onCancelled(DatabaseError databaseError) {
                    if (!exited) {
                        listener.onFailure(databaseError.toException());
                        connected = true;
                    }
                }
            });

            try {
                sleep(timeout);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

            if (!connected) {
                listener.onFailure(new Exception("Timeout, request exceeded " + timeout + "ms timeout"));
                exited = true;
            }
        }
    };

    thread.start();
}

I need this because I want to check if for example a username is already taken, and I don't want to proceed if I can't get a value from the db.

Okay so I thought this works pretty good but following scenario doesn't work:

When I'm in airplane mode and make a request, the timeout exception fires as expected. Then I disable airplane mode and make another request. I get another timeout exception.

EDIT: this goes on for 2 minutes, until a request is successful again.

Turning on Database logging, it seems that it doesn't even try to get the value.

I've also read this .

Is there anything I can do about it?

Answer 1

When I run your code with version 10.0.1, I see the reported behavior except the delay before requests are successful again is only about 20 seconds.

It appears that when a connection becomes available after exiting Airplane Mode, it takes Firebase a short time to detect the change. You can see when Firebase recognizes the change by adding a connection state listener :

    FirebaseDatabase.getInstance().getReference(".info/connected")
            .addValueEventListener(new ValueEventListener() {
                @Override
                public void onDataChange(DataSnapshot snapshot) {
                    if (snapshot.getValue(Boolean.class)) {
                        Log.i(TAG, "Firebase CONNECTED");
                    } else {
                        Log.i(TAG, "Firebase NOT CONNECTED");
                    }
                }

                @Override
                public void onCancelled(DatabaseError error) {
                    Log.e(TAG, "onCancelled: ", error.toException());
                }
            });