Example #1
0
func (sws *serverWatchStream) recvLoop() error {
	for {
		req, err := sws.gRPCStream.Recv()
		if err == io.EOF {
			return nil
		}
		if err != nil {
			return err
		}

		switch uv := req.RequestUnion.(type) {
		case *pb.WatchRequest_CreateRequest:
			if uv.CreateRequest == nil {
				break
			}

			creq := uv.CreateRequest
			if len(creq.Key) == 0 {
				// \x00 is the smallest key
				creq.Key = []byte{0}
			}
			if len(creq.RangeEnd) == 1 && creq.RangeEnd[0] == 0 {
				// support  >= key queries
				creq.RangeEnd = []byte{}
			}
			wsrev := sws.watchStream.Rev()
			rev := creq.StartRevision
			if rev == 0 {
				rev = wsrev + 1
			}
			id := sws.watchStream.Watch(creq.Key, creq.RangeEnd, rev)
			if id != -1 && creq.ProgressNotify {
				sws.progress[id] = true
			}
			sws.ctrlStream <- &pb.WatchResponse{
				Header:   sws.newResponseHeader(wsrev),
				WatchId:  int64(id),
				Created:  true,
				Canceled: id == -1,
			}
		case *pb.WatchRequest_CancelRequest:
			if uv.CancelRequest != nil {
				id := uv.CancelRequest.WatchId
				err := sws.watchStream.Cancel(storage.WatchID(id))
				if err == nil {
					sws.ctrlStream <- &pb.WatchResponse{
						Header:   sws.newResponseHeader(sws.watchStream.Rev()),
						WatchId:  id,
						Canceled: true,
					}
					delete(sws.progress, storage.WatchID(id))
				}
			}
			// TODO: do we need to return error back to client?
		default:
			panic("not implemented")
		}
	}
}
Example #2
0
File: watch.go Project: vsayer/etcd
func (sws *serverWatchStream) recvLoop() error {
	for {
		req, err := sws.gRPCStream.Recv()
		if err == io.EOF {
			return nil
		}
		if err != nil {
			return err
		}

		switch uv := req.RequestUnion.(type) {
		case *pb.WatchRequest_CreateRequest:
			if uv.CreateRequest != nil {
				creq := uv.CreateRequest
				var prefix bool
				toWatch := creq.Key
				if len(creq.Key) == 0 {
					toWatch = creq.Prefix
					prefix = true
				}

				rev := creq.StartRevision
				wsrev := sws.watchStream.Rev()
				if rev == 0 {
					// rev 0 watches past the current revision
					rev = wsrev + 1
				} else if rev > wsrev { // do not allow watching future revision.
					sws.ctrlStream <- &pb.WatchResponse{
						Header:   sws.newResponseHeader(wsrev),
						WatchId:  -1,
						Created:  true,
						Canceled: true,
					}
					continue
				}
				id := sws.watchStream.Watch(toWatch, prefix, rev)
				sws.ctrlStream <- &pb.WatchResponse{
					Header:  sws.newResponseHeader(wsrev),
					WatchId: int64(id),
					Created: true,
				}
			}
		case *pb.WatchRequest_CancelRequest:
			if uv.CancelRequest != nil {
				id := uv.CancelRequest.WatchId
				err := sws.watchStream.Cancel(storage.WatchID(id))
				if err == nil {
					sws.ctrlStream <- &pb.WatchResponse{
						Header:   sws.newResponseHeader(sws.watchStream.Rev()),
						WatchId:  id,
						Canceled: true,
					}
				}
			}
			// TODO: do we need to return error back to client?
		default:
			panic("not implemented")
		}
	}
}
Example #3
0
File: watch.go Project: Gwill/etcd
func newWatcher(c *EtcdClient, key string, rev int64, isPrefix bool) (*Watcher, error) {
	w, err := c.Watch.Watch(context.Background())
	if err != nil {
		return nil, err
	}

	req := &pb.WatchCreateRequest{StartRevision: rev}
	if isPrefix {
		req.Prefix = []byte(key)
	} else {
		req.Key = []byte(key)
	}

	if err := w.Send(&pb.WatchRequest{CreateRequest: req}); err != nil {
		return nil, err
	}

	wresp, err := w.Recv()
	if err != nil {
		return nil, err
	}
	if len(wresp.Events) != 0 || wresp.Created != true {
		return nil, ErrWaitMismatch
	}
	ret := &Watcher{
		wstream: w,
		donec:   make(chan struct{}),
		id:      storage.WatchID(wresp.WatchId),
		recvc:   make(chan *storagepb.Event),
	}
	go ret.recvLoop()
	return ret, nil
}
Example #4
0
func (sws *serverWatchStream) recvLoop() error {
	for {
		req, err := sws.gRPCStream.Recv()
		if err == io.EOF {
			return nil
		}
		if err != nil {
			return err
		}

		switch {
		case req.CreateRequest != nil:
			creq := req.CreateRequest
			var prefix bool
			toWatch := creq.Key
			if len(creq.Key) == 0 {
				toWatch = creq.Prefix
				prefix = true
			}
			id := sws.watchStream.Watch(toWatch, prefix, creq.StartRevision)
			sws.ctrlStream <- &pb.WatchResponse{
				Header:  sws.newResponseHeader(sws.watchStream.Rev()),
				WatchId: int64(id),
				Created: true,
			}
		case req.CancelRequest != nil:
			id := req.CancelRequest.WatchId
			err := sws.watchStream.Cancel(storage.WatchID(id))
			if err == nil {
				sws.ctrlStream <- &pb.WatchResponse{
					Header:   sws.newResponseHeader(sws.watchStream.Rev()),
					WatchId:  id,
					Canceled: true,
				}
			}
			// TODO: do we need to return error back to client?
		default:
			panic("not implemented")
		}
	}
}
Example #5
0
func (sws *serverWatchStream) sendLoop() {
	// watch ids that are currently active
	ids := make(map[storage.WatchID]struct{})
	// watch responses pending on a watch id creation message
	pending := make(map[storage.WatchID][]*pb.WatchResponse)

	progressTicker := time.NewTicker(ProgressReportInterval)
	defer progressTicker.Stop()

	for {
		select {
		case wresp, ok := <-sws.watchStream.Chan():
			if !ok {
				return
			}

			// TODO: evs is []storagepb.Event type
			// either return []*storagepb.Event from storage package
			// or define protocol buffer with []storagepb.Event.
			evs := wresp.Events
			events := make([]*storagepb.Event, len(evs))
			for i := range evs {
				events[i] = &evs[i]
			}

			wr := &pb.WatchResponse{
				Header:          sws.newResponseHeader(wresp.Revision),
				WatchId:         int64(wresp.WatchID),
				Events:          events,
				CompactRevision: wresp.CompactRevision,
			}

			if _, hasId := ids[wresp.WatchID]; !hasId {
				// buffer if id not yet announced
				wrs := append(pending[wresp.WatchID], wr)
				pending[wresp.WatchID] = wrs
				continue
			}

			storage.ReportEventReceived()
			if err := sws.gRPCStream.Send(wr); err != nil {
				return
			}

			if _, ok := sws.progress[wresp.WatchID]; ok {
				sws.progress[wresp.WatchID] = false
			}

		case c, ok := <-sws.ctrlStream:
			if !ok {
				return
			}

			if err := sws.gRPCStream.Send(c); err != nil {
				return
			}

			// track id creation
			wid := storage.WatchID(c.WatchId)
			if c.Canceled {
				delete(ids, wid)
				continue
			}
			if c.Created {
				// flush buffered events
				ids[wid] = struct{}{}
				for _, v := range pending[wid] {
					storage.ReportEventReceived()
					if err := sws.gRPCStream.Send(v); err != nil {
						return
					}
				}
				delete(pending, wid)
			}
		case <-progressTicker.C:
			for id, ok := range sws.progress {
				if ok {
					sws.watchStream.RequestProgress(id)
				}
				sws.progress[id] = true
			}
		case <-sws.closec:
			// drain the chan to clean up pending events
			for range sws.watchStream.Chan() {
				storage.ReportEventReceived()
			}
			for _, wrs := range pending {
				for range wrs {
					storage.ReportEventReceived()
				}
			}
		}
	}
}