diff options
Diffstat (limited to 'go/vendor/google.golang.org/grpc/transport/http2_server.go')
| -rw-r--r-- | go/vendor/google.golang.org/grpc/transport/http2_server.go | 1074 |
1 files changed, 1074 insertions, 0 deletions
diff --git a/go/vendor/google.golang.org/grpc/transport/http2_server.go b/go/vendor/google.golang.org/grpc/transport/http2_server.go new file mode 100644 index 0000000..31fefc7 --- /dev/null +++ b/go/vendor/google.golang.org/grpc/transport/http2_server.go @@ -0,0 +1,1074 @@ +/* + * + * Copyright 2014, Google Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Google Inc. nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +package transport + +import ( + "bytes" + "errors" + "io" + "math" + "math/rand" + "net" + "strconv" + "sync" + "sync/atomic" + "time" + + "github.com/golang/protobuf/proto" + "golang.org/x/net/context" + "golang.org/x/net/http2" + "golang.org/x/net/http2/hpack" + "google.golang.org/grpc/codes" + "google.golang.org/grpc/credentials" + "google.golang.org/grpc/grpclog" + "google.golang.org/grpc/keepalive" + "google.golang.org/grpc/metadata" + "google.golang.org/grpc/peer" + "google.golang.org/grpc/stats" + "google.golang.org/grpc/status" + "google.golang.org/grpc/tap" +) + +// ErrIllegalHeaderWrite indicates that setting header is illegal because of +// the stream's state. +var ErrIllegalHeaderWrite = errors.New("transport: the stream is done or WriteHeader was already called") + +// http2Server implements the ServerTransport interface with HTTP2. +type http2Server struct { + ctx context.Context + conn net.Conn + remoteAddr net.Addr + localAddr net.Addr + maxStreamID uint32 // max stream ID ever seen + authInfo credentials.AuthInfo // auth info about the connection + inTapHandle tap.ServerInHandle + // writableChan synchronizes write access to the transport. + // A writer acquires the write lock by receiving a value on writableChan + // and releases it by sending on writableChan. + writableChan chan int + // shutdownChan is closed when Close is called. + // Blocking operations should select on shutdownChan to avoid + // blocking forever after Close. + shutdownChan chan struct{} + framer *framer + hBuf *bytes.Buffer // the buffer for HPACK encoding + hEnc *hpack.Encoder // HPACK encoder + + // The max number of concurrent streams. + maxStreams uint32 + // controlBuf delivers all the control related tasks (e.g., window + // updates, reset streams, and various settings) to the controller. + controlBuf *recvBuffer + fc *inFlow + // sendQuotaPool provides flow control to outbound message. + sendQuotaPool *quotaPool + + stats stats.Handler + + // Flag to keep track of reading activity on transport. + // 1 is true and 0 is false. + activity uint32 // Accessed atomically. + // Keepalive and max-age parameters for the server. + kp keepalive.ServerParameters + + // Keepalive enforcement policy. + kep keepalive.EnforcementPolicy + // The time instance last ping was received. + lastPingAt time.Time + // Number of times the client has violated keepalive ping policy so far. + pingStrikes uint8 + // Flag to signify that number of ping strikes should be reset to 0. + // This is set whenever data or header frames are sent. + // 1 means yes. + resetPingStrikes uint32 // Accessed atomically. + + mu sync.Mutex // guard the following + state transportState + activeStreams map[uint32]*Stream + // the per-stream outbound flow control window size set by the peer. + streamSendQuota uint32 + // idle is the time instant when the connection went idle. + // This is either the begining of the connection or when the number of + // RPCs go down to 0. + // When the connection is busy, this value is set to 0. + idle time.Time +} + +// newHTTP2Server constructs a ServerTransport based on HTTP2. ConnectionError is +// returned if something goes wrong. +func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err error) { + framer := newFramer(conn) + // Send initial settings as connection preface to client. + var settings []http2.Setting + // TODO(zhaoq): Have a better way to signal "no limit" because 0 is + // permitted in the HTTP2 spec. + maxStreams := config.MaxStreams + if maxStreams == 0 { + maxStreams = math.MaxUint32 + } else { + settings = append(settings, http2.Setting{ + ID: http2.SettingMaxConcurrentStreams, + Val: maxStreams, + }) + } + if initialWindowSize != defaultWindowSize { + settings = append(settings, http2.Setting{ + ID: http2.SettingInitialWindowSize, + Val: uint32(initialWindowSize)}) + } + if err := framer.writeSettings(true, settings...); err != nil { + return nil, connectionErrorf(true, err, "transport: %v", err) + } + // Adjust the connection flow control window if needed. + if delta := uint32(initialConnWindowSize - defaultWindowSize); delta > 0 { + if err := framer.writeWindowUpdate(true, 0, delta); err != nil { + return nil, connectionErrorf(true, err, "transport: %v", err) + } + } + kp := config.KeepaliveParams + if kp.MaxConnectionIdle == 0 { + kp.MaxConnectionIdle = defaultMaxConnectionIdle + } + if kp.MaxConnectionAge == 0 { + kp.MaxConnectionAge = defaultMaxConnectionAge + } + // Add a jitter to MaxConnectionAge. + kp.MaxConnectionAge += getJitter(kp.MaxConnectionAge) + if kp.MaxConnectionAgeGrace == 0 { + kp.MaxConnectionAgeGrace = defaultMaxConnectionAgeGrace + } + if kp.Time == 0 { + kp.Time = defaultServerKeepaliveTime + } + if kp.Timeout == 0 { + kp.Timeout = defaultServerKeepaliveTimeout + } + kep := config.KeepalivePolicy + if kep.MinTime == 0 { + kep.MinTime = defaultKeepalivePolicyMinTime + } + var buf bytes.Buffer + t := &http2Server{ + ctx: context.Background(), + conn: conn, + remoteAddr: conn.RemoteAddr(), + localAddr: conn.LocalAddr(), + authInfo: config.AuthInfo, + framer: framer, + hBuf: &buf, + hEnc: hpack.NewEncoder(&buf), + maxStreams: maxStreams, + inTapHandle: config.InTapHandle, + controlBuf: newRecvBuffer(), + fc: &inFlow{limit: initialConnWindowSize}, + sendQuotaPool: newQuotaPool(defaultWindowSize), + state: reachable, + writableChan: make(chan int, 1), + shutdownChan: make(chan struct{}), + activeStreams: make(map[uint32]*Stream), + streamSendQuota: defaultWindowSize, + stats: config.StatsHandler, + kp: kp, + idle: time.Now(), + kep: kep, + } + if t.stats != nil { + t.ctx = t.stats.TagConn(t.ctx, &stats.ConnTagInfo{ + RemoteAddr: t.remoteAddr, + LocalAddr: t.localAddr, + }) + connBegin := &stats.ConnBegin{} + t.stats.HandleConn(t.ctx, connBegin) + } + go t.controller() + go t.keepalive() + t.writableChan <- 0 + return t, nil +} + +// operateHeader takes action on the decoded headers. +func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (close bool) { + buf := newRecvBuffer() + s := &Stream{ + id: frame.Header().StreamID, + st: t, + buf: buf, + fc: &inFlow{limit: initialWindowSize}, + } + + var state decodeState + for _, hf := range frame.Fields { + if err := state.processHeaderField(hf); err != nil { + if se, ok := err.(StreamError); ok { + t.controlBuf.put(&resetStream{s.id, statusCodeConvTab[se.Code]}) + } + return + } + } + + if frame.StreamEnded() { + // s is just created by the caller. No lock needed. + s.state = streamReadDone + } + s.recvCompress = state.encoding + if state.timeoutSet { + s.ctx, s.cancel = context.WithTimeout(t.ctx, state.timeout) + } else { + s.ctx, s.cancel = context.WithCancel(t.ctx) + } + pr := &peer.Peer{ + Addr: t.remoteAddr, + } + // Attach Auth info if there is any. + if t.authInfo != nil { + pr.AuthInfo = t.authInfo + } + s.ctx = peer.NewContext(s.ctx, pr) + // Cache the current stream to the context so that the server application + // can find out. Required when the server wants to send some metadata + // back to the client (unary call only). + s.ctx = newContextWithStream(s.ctx, s) + // Attach the received metadata to the context. + if len(state.mdata) > 0 { + s.ctx = metadata.NewIncomingContext(s.ctx, state.mdata) + } + + s.dec = &recvBufferReader{ + ctx: s.ctx, + recv: s.buf, + } + s.recvCompress = state.encoding + s.method = state.method + if t.inTapHandle != nil { + var err error + info := &tap.Info{ + FullMethodName: state.method, + } + s.ctx, err = t.inTapHandle(s.ctx, info) + if err != nil { + // TODO: Log the real error. + t.controlBuf.put(&resetStream{s.id, http2.ErrCodeRefusedStream}) + return + } + } + t.mu.Lock() + if t.state != reachable { + t.mu.Unlock() + return + } + if uint32(len(t.activeStreams)) >= t.maxStreams { + t.mu.Unlock() + t.controlBuf.put(&resetStream{s.id, http2.ErrCodeRefusedStream}) + return + } + if s.id%2 != 1 || s.id <= t.maxStreamID { + t.mu.Unlock() + // illegal gRPC stream id. + grpclog.Println("transport: http2Server.HandleStreams received an illegal stream id: ", s.id) + return true + } + t.maxStreamID = s.id + s.sendQuotaPool = newQuotaPool(int(t.streamSendQuota)) + t.activeStreams[s.id] = s + if len(t.activeStreams) == 1 { + t.idle = time.Time{} + } + t.mu.Unlock() + s.windowHandler = func(n int) { + t.updateWindow(s, uint32(n)) + } + s.ctx = traceCtx(s.ctx, s.method) + if t.stats != nil { + s.ctx = t.stats.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method}) + inHeader := &stats.InHeader{ + FullMethod: s.method, + RemoteAddr: t.remoteAddr, + LocalAddr: t.localAddr, + Compression: s.recvCompress, + WireLength: int(frame.Header().Length), + } + t.stats.HandleRPC(s.ctx, inHeader) + } + handle(s) + return +} + +// HandleStreams receives incoming streams using the given handler. This is +// typically run in a separate goroutine. +// traceCtx attaches trace to ctx and returns the new context. +func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.Context, string) context.Context) { + // Check the validity of client preface. + preface := make([]byte, len(clientPreface)) + if _, err := io.ReadFull(t.conn, preface); err != nil { + grpclog.Printf("transport: http2Server.HandleStreams failed to receive the preface from client: %v", err) + t.Close() + return + } + if !bytes.Equal(preface, clientPreface) { + grpclog.Printf("transport: http2Server.HandleStreams received bogus greeting from client: %q", preface) + t.Close() + return + } + + frame, err := t.framer.readFrame() + if err == io.EOF || err == io.ErrUnexpectedEOF { + t.Close() + return + } + if err != nil { + grpclog.Printf("transport: http2Server.HandleStreams failed to read frame: %v", err) + t.Close() + return + } + atomic.StoreUint32(&t.activity, 1) + sf, ok := frame.(*http2.SettingsFrame) + if !ok { + grpclog.Printf("transport: http2Server.HandleStreams saw invalid preface type %T from client", frame) + t.Close() + return + } + t.handleSettings(sf) + + for { + frame, err := t.framer.readFrame() + atomic.StoreUint32(&t.activity, 1) + if err != nil { + if se, ok := err.(http2.StreamError); ok { + t.mu.Lock() + s := t.activeStreams[se.StreamID] + t.mu.Unlock() + if s != nil { + t.closeStream(s) + } + t.controlBuf.put(&resetStream{se.StreamID, se.Code}) + continue + } + if err == io.EOF || err == io.ErrUnexpectedEOF { + t.Close() + return + } + grpclog.Printf("transport: http2Server.HandleStreams failed to read frame: %v", err) + t.Close() + return + } + switch frame := frame.(type) { + case *http2.MetaHeadersFrame: + if t.operateHeaders(frame, handle, traceCtx) { + t.Close() + break + } + case *http2.DataFrame: + t.handleData(frame) + case *http2.RSTStreamFrame: + t.handleRSTStream(frame) + case *http2.SettingsFrame: + t.handleSettings(frame) + case *http2.PingFrame: + t.handlePing(frame) + case *http2.WindowUpdateFrame: + t.handleWindowUpdate(frame) + case *http2.GoAwayFrame: + // TODO: Handle GoAway from the client appropriately. + default: + grpclog.Printf("transport: http2Server.HandleStreams found unhandled frame type %v.", frame) + } + } +} + +func (t *http2Server) getStream(f http2.Frame) (*Stream, bool) { + t.mu.Lock() + defer t.mu.Unlock() + if t.activeStreams == nil { + // The transport is closing. + return nil, false + } + s, ok := t.activeStreams[f.Header().StreamID] + if !ok { + // The stream is already done. + return nil, false + } + return s, true +} + +// updateWindow adjusts the inbound quota for the stream and the transport. +// Window updates will deliver to the controller for sending when +// the cumulative quota exceeds the corresponding threshold. +func (t *http2Server) updateWindow(s *Stream, n uint32) { + s.mu.Lock() + defer s.mu.Unlock() + if s.state == streamDone { + return + } + if w := t.fc.onRead(n); w > 0 { + t.controlBuf.put(&windowUpdate{0, w}) + } + if w := s.fc.onRead(n); w > 0 { + t.controlBuf.put(&windowUpdate{s.id, w}) + } +} + +func (t *http2Server) handleData(f *http2.DataFrame) { + size := f.Header().Length + if err := t.fc.onData(uint32(size)); err != nil { + grpclog.Printf("transport: http2Server %v", err) + t.Close() + return + } + // Select the right stream to dispatch. + s, ok := t.getStream(f) + if !ok { + if w := t.fc.onRead(uint32(size)); w > 0 { + t.controlBuf.put(&windowUpdate{0, w}) + } + return + } + if size > 0 { + if f.Header().Flags.Has(http2.FlagDataPadded) { + if w := t.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 { + t.controlBuf.put(&windowUpdate{0, w}) + } + } + s.mu.Lock() + if s.state == streamDone { + s.mu.Unlock() + // The stream has been closed. Release the corresponding quota. + if w := t.fc.onRead(uint32(size)); w > 0 { + t.controlBuf.put(&windowUpdate{0, w}) + } + return + } + if err := s.fc.onData(uint32(size)); err != nil { + s.mu.Unlock() + t.closeStream(s) + t.controlBuf.put(&resetStream{s.id, http2.ErrCodeFlowControl}) + return + } + if f.Header().Flags.Has(http2.FlagDataPadded) { + if w := s.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 { + t.controlBuf.put(&windowUpdate{s.id, w}) + } + } + s.mu.Unlock() + // TODO(bradfitz, zhaoq): A copy is required here because there is no + // guarantee f.Data() is consumed before the arrival of next frame. + // Can this copy be eliminated? + if len(f.Data()) > 0 { + data := make([]byte, len(f.Data())) + copy(data, f.Data()) + s.write(recvMsg{data: data}) + } + } + if f.Header().Flags.Has(http2.FlagDataEndStream) { + // Received the end of stream from the client. + s.mu.Lock() + if s.state != streamDone { + s.state = streamReadDone + } + s.mu.Unlock() + s.write(recvMsg{err: io.EOF}) + } +} + +func (t *http2Server) handleRSTStream(f *http2.RSTStreamFrame) { + s, ok := t.getStream(f) + if !ok { + return + } + t.closeStream(s) +} + +func (t *http2Server) handleSettings(f *http2.SettingsFrame) { + if f.IsAck() { + return + } + var ss []http2.Setting + f.ForeachSetting(func(s http2.Setting) error { + ss = append(ss, s) + return nil + }) + // The settings will be applied once the ack is sent. + t.controlBuf.put(&settings{ack: true, ss: ss}) +} + +const ( + maxPingStrikes = 2 + defaultPingTimeout = 2 * time.Hour +) + +func (t *http2Server) handlePing(f *http2.PingFrame) { + if f.IsAck() { // Do nothing. + return + } + pingAck := &ping{ack: true} + copy(pingAck.data[:], f.Data[:]) + t.controlBuf.put(pingAck) + + now := time.Now() + defer func() { + t.lastPingAt = now + }() + // A reset ping strikes means that we don't need to check for policy + // violation for this ping and the pingStrikes counter should be set + // to 0. + if atomic.CompareAndSwapUint32(&t.resetPingStrikes, 1, 0) { + t.pingStrikes = 0 + return + } + t.mu.Lock() + ns := len(t.activeStreams) + t.mu.Unlock() + if ns < 1 && !t.kep.PermitWithoutStream { + // Keepalive shouldn't be active thus, this new ping should + // have come after atleast defaultPingTimeout. + if t.lastPingAt.Add(defaultPingTimeout).After(now) { + t.pingStrikes++ + } + } else { + // Check if keepalive policy is respected. + if t.lastPingAt.Add(t.kep.MinTime).After(now) { + t.pingStrikes++ + } + } + + if t.pingStrikes > maxPingStrikes { + // Send goaway and close the connection. + t.controlBuf.put(&goAway{code: http2.ErrCodeEnhanceYourCalm, debugData: []byte("too_many_pings")}) + } +} + +func (t *http2Server) handleWindowUpdate(f *http2.WindowUpdateFrame) { + id := f.Header().StreamID + incr := f.Increment + if id == 0 { + t.sendQuotaPool.add(int(incr)) + return + } + if s, ok := t.getStream(f); ok { + s.sendQuotaPool.add(int(incr)) + } +} + +func (t *http2Server) writeHeaders(s *Stream, b *bytes.Buffer, endStream bool) error { + first := true + endHeaders := false + var err error + defer func() { + if err == nil { + // Reset ping strikes when seding headers since that might cause the + // peer to send ping. + atomic.StoreUint32(&t.resetPingStrikes, 1) + } + }() + // Sends the headers in a single batch. + for !endHeaders { + size := t.hBuf.Len() + if size > http2MaxFrameLen { + size = http2MaxFrameLen + } else { + endHeaders = true + } + if first { + p := http2.HeadersFrameParam{ + StreamID: s.id, + BlockFragment: b.Next(size), + EndStream: endStream, + EndHeaders: endHeaders, + } + err = t.framer.writeHeaders(endHeaders, p) + first = false + } else { + err = t.framer.writeContinuation(endHeaders, s.id, endHeaders, b.Next(size)) + } + if err != nil { + t.Close() + return connectionErrorf(true, err, "transport: %v", err) + } + } + return nil +} + +// WriteHeader sends the header metedata md back to the client. +func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error { + s.mu.Lock() + if s.headerOk || s.state == streamDone { + s.mu.Unlock() + return ErrIllegalHeaderWrite + } + s.headerOk = true + if md.Len() > 0 { + if s.header.Len() > 0 { + s.header = metadata.Join(s.header, md) + } else { + s.header = md + } + } + md = s.header + s.mu.Unlock() + if _, err := wait(s.ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil { + return err + } + t.hBuf.Reset() + t.hEnc.WriteField(hpack.HeaderField{Name: ":status", Value: "200"}) + t.hEnc.WriteField(hpack.HeaderField{Name: "content-type", Value: "application/grpc"}) + if s.sendCompress != "" { + t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-encoding", Value: s.sendCompress}) + } + for k, v := range md { + if isReservedHeader(k) { + // Clients don't tolerate reading restricted headers after some non restricted ones were sent. + continue + } + for _, entry := range v { + t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry}) + } + } + bufLen := t.hBuf.Len() + if err := t.writeHeaders(s, t.hBuf, false); err != nil { + return err + } + if t.stats != nil { + outHeader := &stats.OutHeader{ + WireLength: bufLen, + } + t.stats.HandleRPC(s.Context(), outHeader) + } + t.writableChan <- 0 + return nil +} + +// WriteStatus sends stream status to the client and terminates the stream. +// There is no further I/O operations being able to perform on this stream. +// TODO(zhaoq): Now it indicates the end of entire stream. Revisit if early +// OK is adopted. +func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error { + var headersSent, hasHeader bool + s.mu.Lock() + if s.state == streamDone { + s.mu.Unlock() + return nil + } + if s.headerOk { + headersSent = true + } + if s.header.Len() > 0 { + hasHeader = true + } + s.mu.Unlock() + + if !headersSent && hasHeader { + t.WriteHeader(s, nil) + headersSent = true + } + + if _, err := wait(s.ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil { + return err + } + t.hBuf.Reset() + if !headersSent { + t.hEnc.WriteField(hpack.HeaderField{Name: ":status", Value: "200"}) + t.hEnc.WriteField(hpack.HeaderField{Name: "content-type", Value: "application/grpc"}) + } + t.hEnc.WriteField( + hpack.HeaderField{ + Name: "grpc-status", + Value: strconv.Itoa(int(st.Code())), + }) + t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(st.Message())}) + + if p := st.Proto(); p != nil && len(p.Details) > 0 { + stBytes, err := proto.Marshal(p) + if err != nil { + // TODO: return error instead, when callers are able to handle it. + panic(err) + } + + for k, v := range metadata.New(map[string]string{"grpc-status-details-bin": (string)(stBytes)}) { + for _, entry := range v { + t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry}) + } + } + } + + // Attach the trailer metadata. + for k, v := range s.trailer { + // Clients don't tolerate reading restricted headers after some non restricted ones were sent. + if isReservedHeader(k) { + continue + } + for _, entry := range v { + t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry}) + } + } + bufLen := t.hBuf.Len() + if err := t.writeHeaders(s, t.hBuf, true); err != nil { + t.Close() + return err + } + if t.stats != nil { + outTrailer := &stats.OutTrailer{ + WireLength: bufLen, + } + t.stats.HandleRPC(s.Context(), outTrailer) + } + t.closeStream(s) + t.writableChan <- 0 + return nil +} + +// Write converts the data into HTTP2 data frame and sends it out. Non-nil error +// is returns if it fails (e.g., framing error, transport error). +func (t *http2Server) Write(s *Stream, data []byte, opts *Options) (err error) { + // TODO(zhaoq): Support multi-writers for a single stream. + var writeHeaderFrame bool + s.mu.Lock() + if s.state == streamDone { + s.mu.Unlock() + return streamErrorf(codes.Unknown, "the stream has been done") + } + if !s.headerOk { + writeHeaderFrame = true + } + s.mu.Unlock() + if writeHeaderFrame { + t.WriteHeader(s, nil) + } + defer func() { + if err == nil { + // Reset ping strikes when sending data since this might cause + // the peer to send ping. + atomic.StoreUint32(&t.resetPingStrikes, 1) + } + }() + r := bytes.NewBuffer(data) + for { + if r.Len() == 0 { + return nil + } + size := http2MaxFrameLen + // Wait until the stream has some quota to send the data. + sq, err := wait(s.ctx, nil, nil, t.shutdownChan, s.sendQuotaPool.acquire()) + if err != nil { + return err + } + // Wait until the transport has some quota to send the data. + tq, err := wait(s.ctx, nil, nil, t.shutdownChan, t.sendQuotaPool.acquire()) + if err != nil { + return err + } + if sq < size { + size = sq + } + if tq < size { + size = tq + } + p := r.Next(size) + ps := len(p) + if ps < sq { + // Overbooked stream quota. Return it back. + s.sendQuotaPool.add(sq - ps) + } + if ps < tq { + // Overbooked transport quota. Return it back. + t.sendQuotaPool.add(tq - ps) + } + t.framer.adjustNumWriters(1) + // Got some quota. Try to acquire writing privilege on the + // transport. + if _, err := wait(s.ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil { + if _, ok := err.(StreamError); ok { + // Return the connection quota back. + t.sendQuotaPool.add(ps) + } + if t.framer.adjustNumWriters(-1) == 0 { + // This writer is the last one in this batch and has the + // responsibility to flush the buffered frames. It queues + // a flush request to controlBuf instead of flushing directly + // in order to avoid the race with other writing or flushing. + t.controlBuf.put(&flushIO{}) + } + return err + } + select { + case <-s.ctx.Done(): + t.sendQuotaPool.add(ps) + if t.framer.adjustNumWriters(-1) == 0 { + t.controlBuf.put(&flushIO{}) + } + t.writableChan <- 0 + return ContextErr(s.ctx.Err()) + default: + } + var forceFlush bool + if r.Len() == 0 && t.framer.adjustNumWriters(0) == 1 && !opts.Last { + forceFlush = true + } + if err := t.framer.writeData(forceFlush, s.id, false, p); err != nil { + t.Close() + return connectionErrorf(true, err, "transport: %v", err) + } + if t.framer.adjustNumWriters(-1) == 0 { + t.framer.flushWrite() + } + t.writableChan <- 0 + } + +} + +func (t *http2Server) applySettings(ss []http2.Setting) { + for _, s := range ss { + if s.ID == http2.SettingInitialWindowSize { + t.mu.Lock() + defer t.mu.Unlock() + for _, stream := range t.activeStreams { + stream.sendQuotaPool.add(int(s.Val - t.streamSendQuota)) + } + t.streamSendQuota = s.Val + } + + } +} + +// keepalive running in a separate goroutine does the following: +// 1. Gracefully closes an idle connection after a duration of keepalive.MaxConnectionIdle. +// 2. Gracefully closes any connection after a duration of keepalive.MaxConnectionAge. +// 3. Forcibly closes a connection after an additive period of keepalive.MaxConnectionAgeGrace over keepalive.MaxConnectionAge. +// 4. Makes sure a connection is alive by sending pings with a frequency of keepalive.Time and closes a non-resposive connection +// after an additional duration of keepalive.Timeout. +func (t *http2Server) keepalive() { + p := &ping{} + var pingSent bool + maxIdle := time.NewTimer(t.kp.MaxConnectionIdle) + maxAge := time.NewTimer(t.kp.MaxConnectionAge) + keepalive := time.NewTimer(t.kp.Time) + // NOTE: All exit paths of this function should reset their + // respecitve timers. A failure to do so will cause the + // following clean-up to deadlock and eventually leak. + defer func() { + if !maxIdle.Stop() { + <-maxIdle.C + } + if !maxAge.Stop() { + <-maxAge.C + } + if !keepalive.Stop() { + <-keepalive.C + } + }() + for { + select { + case <-maxIdle.C: + t.mu.Lock() + idle := t.idle + if idle.IsZero() { // The connection is non-idle. + t.mu.Unlock() + maxIdle.Reset(t.kp.MaxConnectionIdle) + continue + } + val := t.kp.MaxConnectionIdle - time.Since(idle) + if val <= 0 { + // The connection has been idle for a duration of keepalive.MaxConnectionIdle or more. + // Gracefully close the connection. + t.state = draining + t.mu.Unlock() + t.Drain() + // Reseting the timer so that the clean-up doesn't deadlock. + maxIdle.Reset(infinity) + return + } + t.mu.Unlock() + maxIdle.Reset(val) + case <-maxAge.C: + t.mu.Lock() + t.state = draining + t.mu.Unlock() + t.Drain() + maxAge.Reset(t.kp.MaxConnectionAgeGrace) + select { + case <-maxAge.C: + // Close the connection after grace period. + t.Close() + // Reseting the timer so that the clean-up doesn't deadlock. + maxAge.Reset(infinity) + case <-t.shutdownChan: + } + return + case <-keepalive.C: + if atomic.CompareAndSwapUint32(&t.activity, 1, 0) { + pingSent = false + keepalive.Reset(t.kp.Time) + continue + } + if pingSent { + t.Close() + // Reseting the timer so that the clean-up doesn't deadlock. + keepalive.Reset(infinity) + return + } + pingSent = true + t.controlBuf.put(p) + keepalive.Reset(t.kp.Timeout) + case <-t.shutdownChan: + return + } + } +} + +// controller running in a separate goroutine takes charge of sending control +// frames (e.g., window update, reset stream, setting, etc.) to the server. +func (t *http2Server) controller() { + for { + select { + case i := <-t.controlBuf.get(): + t.controlBuf.load() + select { + case <-t.writableChan: + switch i := i.(type) { + case *windowUpdate: + t.framer.writeWindowUpdate(true, i.streamID, i.increment) + case *settings: + if i.ack { + t.framer.writeSettingsAck(true) + t.applySettings(i.ss) + } else { + t.framer.writeSettings(true, i.ss...) + } + case *resetStream: + t.framer.writeRSTStream(true, i.streamID, i.code) + case *goAway: + t.mu.Lock() + if t.state == closing { + t.mu.Unlock() + // The transport is closing. + return + } + sid := t.maxStreamID + t.state = draining + t.mu.Unlock() + t.framer.writeGoAway(true, sid, i.code, i.debugData) + if i.code == http2.ErrCodeEnhanceYourCalm { + t.Close() + } + case *flushIO: + t.framer.flushWrite() + case *ping: + t.framer.writePing(true, i.ack, i.data) + default: + grpclog.Printf("transport: http2Server.controller got unexpected item type %v\n", i) + } + t.writableChan <- 0 + continue + case <-t.shutdownChan: + return + } + case <-t.shutdownChan: + return + } + } +} + +// Close starts shutting down the http2Server transport. +// TODO(zhaoq): Now the destruction is not blocked on any pending streams. This +// could cause some resource issue. Revisit this later. +func (t *http2Server) Close() (err error) { + t.mu.Lock() + if t.state == closing { + t.mu.Unlock() + return errors.New("transport: Close() was already called") + } + t.state = closing + streams := t.activeStreams + t.activeStreams = nil + t.mu.Unlock() + close(t.shutdownChan) + err = t.conn.Close() + // Cancel all active streams. + for _, s := range streams { + s.cancel() + } + if t.stats != nil { + connEnd := &stats.ConnEnd{} + t.stats.HandleConn(t.ctx, connEnd) + } + return +} + +// closeStream clears the footprint of a stream when the stream is not needed +// any more. +func (t *http2Server) closeStream(s *Stream) { + t.mu.Lock() + delete(t.activeStreams, s.id) + if len(t.activeStreams) == 0 { + t.idle = time.Now() + } + if t.state == draining && len(t.activeStreams) == 0 { + defer t.Close() + } + t.mu.Unlock() + // In case stream sending and receiving are invoked in separate + // goroutines (e.g., bi-directional streaming), cancel needs to be + // called to interrupt the potential blocking on other goroutines. + s.cancel() + s.mu.Lock() + if q := s.fc.resetPendingData(); q > 0 { + if w := t.fc.onRead(q); w > 0 { + t.controlBuf.put(&windowUpdate{0, w}) + } + } + if s.state == streamDone { + s.mu.Unlock() + return + } + s.state = streamDone + s.mu.Unlock() +} + +func (t *http2Server) RemoteAddr() net.Addr { + return t.remoteAddr +} + +func (t *http2Server) Drain() { + t.controlBuf.put(&goAway{code: http2.ErrCodeNo}) +} + +var rgen = rand.New(rand.NewSource(time.Now().UnixNano())) + +func getJitter(v time.Duration) time.Duration { + if v == infinity { + return 0 + } + // Generate a jitter between +/- 10% of the value. + r := int64(v / 10) + j := rgen.Int63n(2*r) - r + return time.Duration(j) +} |