integration: test watch restore on slow follower
@@ -352,6 +352,84 @@ func TestV3WatchFutureRevision(t *testing.T) {
}
}
+// TestV3WatchRestoreSnapshotUnsync tests whether slow follower can restore
+// from leader snapshot, and still notify on watchers from an old revision
+// that were created in synced watcher group in the first place.
+func TestV3WatchRestoreSnapshotUnsync(t *testing.T) {
+ clus := NewClusterV3(t, &ClusterConfig{
+ Size: 3,
+ SnapshotCount: 10,
+ SnapshotCatchUpEntries: 5,
+ })
+ defer clus.Terminate(t)
+
+ // spawn a watcher before shutdown, and put it in synced watcher
+ ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+ defer cancel()
+ wStream, errW := toGRPC(clus.Client(0)).Watch.Watch(ctx)
+ if errW != nil {
+ t.Fatal(errW)
+ }
+ if err := wStream.Send(&pb.WatchRequest{RequestUnion: &pb.WatchRequest_CreateRequest{
+ CreateRequest: &pb.WatchCreateRequest{Key: []byte("foo"), StartRevision: 5}}}); err != nil {
+ t.Fatalf("wStream.Send error: %v", err)
+ }
+ wresp, errR := wStream.Recv()
+ if errR != nil {
+ t.Errorf("wStream.Recv error: %v", errR)
+ }
+ if !wresp.Created {
+ t.Errorf("wresp.Created got = %v, want = true", wresp.Created)
+ }
+
+ clus.Members[0].InjectPartition(t, clus.Members[1:]...)
+ clus.waitLeader(t, clus.Members[1:])
+ time.Sleep(2 * time.Second)
+
+ kvc := toGRPC(clus.Client(1)).KV
+
+ // to trigger snapshot from the leader to the stopped follower
+ for i := 0; i < 15; i++ {
+ _, err := kvc.Put(context.TODO(), &pb.PutRequest{Key: []byte("foo"), Value: []byte("bar")})
+ if err != nil {
+ t.Errorf("#%d: couldn't put key (%v)", i, err)
+ }
+ }
+
+ // trigger snapshot send from leader to this slow follower
+ // which then calls watchable store Restore
+ clus.Members[0].RecoverPartition(t, clus.Members[1:]...)
+ clus.WaitLeader(t)
+ time.Sleep(2 * time.Second)
+
+ // slow follower now applies leader snapshot
+ // should be able to notify on old-revision watchers in unsynced
+ // make sure restore watch operation correctly moves watchers
+ // between synced and unsynced watchers
+ errc := make(chan error)
+ go func() {
+ cresp, cerr := wStream.Recv()
+ if cerr != nil {
+ errc <- cerr
+ return
+ }
+ // from start revision 5 to latest revision 16
+ if len(cresp.Events) != 12 {
+ errc <- fmt.Errorf("expected 12 events, got %+v", cresp.Events)
+ return
+ }
+ errc <- nil
+ }()
+ select {
+ case <-time.After(10 * time.Second):
+ t.Fatal("took too long to receive events from restored watcher")
+ case err := <-errc:
+ if err != nil {
+ t.Fatalf("wStream.Recv error: %v", err)
+ }
+ }
+}
+
// TestV3WatchWrongRange tests wrong range does not create watchers.
func TestV3WatchWrongRange(t *testing.T) {
defer testutil.AfterTest(t)
