Files
containerd/services/streaming/service.go
Derek McGowan d7ef6cbfa3 [streaming] move response packet after registration
Prevent a race where a client may attempt to use a stream
before it is registered.

Signed-off-by: Derek McGowan <derek@mcg.dev>
2022-12-30 21:56:25 -08:00

132 lines
3.0 KiB
Go

/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package streaming
import (
"errors"
"io"
api "github.com/containerd/containerd/api/services/streaming/v1"
"github.com/containerd/containerd/errdefs"
"github.com/containerd/containerd/log"
"github.com/containerd/containerd/pkg/streaming"
"github.com/containerd/containerd/plugin"
"github.com/containerd/containerd/protobuf"
ptypes "github.com/containerd/containerd/protobuf/types"
"github.com/containerd/typeurl"
"google.golang.org/grpc"
)
func init() {
plugin.Register(&plugin.Registration{
Type: plugin.GRPCPlugin,
ID: "streaming",
Requires: []plugin.Type{
plugin.StreamingPlugin,
},
InitFn: func(ic *plugin.InitContext) (interface{}, error) {
i, err := ic.GetByID(plugin.StreamingPlugin, "manager")
if err != nil {
return nil, err
}
return &service{manager: i.(streaming.StreamManager)}, nil
},
})
}
type service struct {
manager streaming.StreamManager
api.UnimplementedStreamingServer
}
func (s *service) Register(server *grpc.Server) error {
api.RegisterStreamingServer(server, s)
return nil
}
func (s *service) Stream(srv api.Streaming_StreamServer) error {
// TODO: Timeout waiting
a, err := srv.Recv()
if err != nil {
return err
}
var i api.StreamInit
if err := typeurl.UnmarshalTo(a, &i); err != nil {
return err
}
// TODO: Save this response to avoid marshaling everytime
response, err := typeurl.MarshalAny(&ptypes.Empty{})
if err != nil {
return err
}
cc := make(chan struct{})
ss := &serviceStream{
s: srv,
cc: cc,
}
log.G(srv.Context()).WithField("stream", i.ID).Debug("registering stream")
if err := s.manager.Register(srv.Context(), i.ID, ss); err != nil {
return err
}
// Send response packet after registering stream
if err := srv.Send(protobuf.FromAny(response)); err != nil {
return err
}
select {
case <-srv.Context().Done():
// TODO: Should return error if not cancelled?
case <-cc:
}
return nil
}
type serviceStream struct {
s api.Streaming_StreamServer
cc chan struct{}
}
func (ss *serviceStream) Send(a typeurl.Any) (err error) {
err = errdefs.FromGRPC(ss.s.Send(protobuf.FromAny(a)))
if !errors.Is(err, io.EOF) {
err = errdefs.FromGRPC(err)
}
return
}
func (ss *serviceStream) Recv() (a typeurl.Any, err error) {
a, err = ss.s.Recv()
if !errors.Is(err, io.EOF) {
err = errdefs.FromGRPC(err)
}
return
}
func (ss *serviceStream) Close() error {
select {
case <-ss.cc:
default:
close(ss.cc)
}
return nil
}