diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/stream.go')
-rw-r--r-- | vendor/google.golang.org/grpc/stream.go | 779 |
1 files changed, 0 insertions, 779 deletions
diff --git a/vendor/google.golang.org/grpc/stream.go b/vendor/google.golang.org/grpc/stream.go deleted file mode 100644 index 152d9eccd..000000000 --- a/vendor/google.golang.org/grpc/stream.go +++ /dev/null @@ -1,779 +0,0 @@ -/* - * - * Copyright 2014 gRPC 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 grpc - -import ( - "errors" - "io" - "sync" - "time" - - "golang.org/x/net/context" - "golang.org/x/net/trace" - "google.golang.org/grpc/balancer" - "google.golang.org/grpc/codes" - "google.golang.org/grpc/encoding" - "google.golang.org/grpc/internal/channelz" - "google.golang.org/grpc/metadata" - "google.golang.org/grpc/stats" - "google.golang.org/grpc/status" - "google.golang.org/grpc/transport" -) - -// StreamHandler defines the handler called by gRPC server to complete the -// execution of a streaming RPC. If a StreamHandler returns an error, it -// should be produced by the status package, or else gRPC will use -// codes.Unknown as the status code and err.Error() as the status message -// of the RPC. -type StreamHandler func(srv interface{}, stream ServerStream) error - -// StreamDesc represents a streaming RPC service's method specification. -type StreamDesc struct { - StreamName string - Handler StreamHandler - - // At least one of these is true. - ServerStreams bool - ClientStreams bool -} - -// Stream defines the common interface a client or server stream has to satisfy. -// -// All errors returned from Stream are compatible with the status package. -type Stream interface { - // Context returns the context for this stream. - Context() context.Context - // SendMsg blocks until it sends m, the stream is done or the stream - // breaks. - // On error, it aborts the stream and returns an RPC status on client - // side. On server side, it simply returns the error to the caller. - // SendMsg is called by generated code. Also Users can call SendMsg - // directly when it is really needed in their use cases. - // It's safe to have a goroutine calling SendMsg and another goroutine calling - // recvMsg on the same stream at the same time. - // But it is not safe to call SendMsg on the same stream in different goroutines. - SendMsg(m interface{}) error - // RecvMsg blocks until it receives a message or the stream is - // done. On client side, it returns io.EOF when the stream is done. On - // any other error, it aborts the stream and returns an RPC status. On - // server side, it simply returns the error to the caller. - // It's safe to have a goroutine calling SendMsg and another goroutine calling - // recvMsg on the same stream at the same time. - // But it is not safe to call RecvMsg on the same stream in different goroutines. - RecvMsg(m interface{}) error -} - -// ClientStream defines the interface a client stream has to satisfy. -type ClientStream interface { - // Header returns the header metadata received from the server if there - // is any. It blocks if the metadata is not ready to read. - Header() (metadata.MD, error) - // Trailer returns the trailer metadata from the server, if there is any. - // It must only be called after stream.CloseAndRecv has returned, or - // stream.Recv has returned a non-nil error (including io.EOF). - Trailer() metadata.MD - // CloseSend closes the send direction of the stream. It closes the stream - // when non-nil error is met. - CloseSend() error - // Stream.SendMsg() may return a non-nil error when something wrong happens sending - // the request. The returned error indicates the status of this sending, not the final - // status of the RPC. - // - // Always call Stream.RecvMsg() to drain the stream and get the final - // status, otherwise there could be leaked resources. - Stream -} - -// NewStream creates a new Stream for the client side. This is typically -// called by generated code. ctx is used for the lifetime of the stream. -// -// To ensure resources are not leaked due to the stream returned, one of the following -// actions must be performed: -// -// 1. Call Close on the ClientConn. -// 2. Cancel the context provided. -// 3. Call RecvMsg until a non-nil error is returned. A protobuf-generated -// client-streaming RPC, for instance, might use the helper function -// CloseAndRecv (note that CloseSend does not Recv, therefore is not -// guaranteed to release all resources). -// 4. Receive a non-nil, non-io.EOF error from Header or SendMsg. -// -// If none of the above happen, a goroutine and a context will be leaked, and grpc -// will not call the optionally-configured stats handler with a stats.End message. -func (cc *ClientConn) NewStream(ctx context.Context, desc *StreamDesc, method string, opts ...CallOption) (ClientStream, error) { - // allow interceptor to see all applicable call options, which means those - // configured as defaults from dial option as well as per-call options - opts = combine(cc.dopts.callOptions, opts) - - if cc.dopts.streamInt != nil { - return cc.dopts.streamInt(ctx, desc, cc, method, newClientStream, opts...) - } - return newClientStream(ctx, desc, cc, method, opts...) -} - -// NewClientStream is a wrapper for ClientConn.NewStream. -// -// DEPRECATED: Use ClientConn.NewStream instead. -func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (ClientStream, error) { - return cc.NewStream(ctx, desc, method, opts...) -} - -func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, method string, opts ...CallOption) (_ ClientStream, err error) { - if channelz.IsOn() { - cc.incrCallsStarted() - defer func() { - if err != nil { - cc.incrCallsFailed() - } - }() - } - c := defaultCallInfo() - mc := cc.GetMethodConfig(method) - if mc.WaitForReady != nil { - c.failFast = !*mc.WaitForReady - } - - // Possible context leak: - // The cancel function for the child context we create will only be called - // when RecvMsg returns a non-nil error, if the ClientConn is closed, or if - // an error is generated by SendMsg. - // https://github.com/grpc/grpc-go/issues/1818. - var cancel context.CancelFunc - if mc.Timeout != nil && *mc.Timeout >= 0 { - ctx, cancel = context.WithTimeout(ctx, *mc.Timeout) - } else { - ctx, cancel = context.WithCancel(ctx) - } - defer func() { - if err != nil { - cancel() - } - }() - - for _, o := range opts { - if err := o.before(c); err != nil { - return nil, toRPCErr(err) - } - } - c.maxSendMessageSize = getMaxSize(mc.MaxReqSize, c.maxSendMessageSize, defaultClientMaxSendMessageSize) - c.maxReceiveMessageSize = getMaxSize(mc.MaxRespSize, c.maxReceiveMessageSize, defaultClientMaxReceiveMessageSize) - if err := setCallInfoCodec(c); err != nil { - return nil, err - } - - callHdr := &transport.CallHdr{ - Host: cc.authority, - Method: method, - // If it's not client streaming, we should already have the request to be sent, - // so we don't flush the header. - // If it's client streaming, the user may never send a request or send it any - // time soon, so we ask the transport to flush the header. - Flush: desc.ClientStreams, - ContentSubtype: c.contentSubtype, - } - - // Set our outgoing compression according to the UseCompressor CallOption, if - // set. In that case, also find the compressor from the encoding package. - // Otherwise, use the compressor configured by the WithCompressor DialOption, - // if set. - var cp Compressor - var comp encoding.Compressor - if ct := c.compressorType; ct != "" { - callHdr.SendCompress = ct - if ct != encoding.Identity { - comp = encoding.GetCompressor(ct) - if comp == nil { - return nil, status.Errorf(codes.Internal, "grpc: Compressor is not installed for requested grpc-encoding %q", ct) - } - } - } else if cc.dopts.cp != nil { - callHdr.SendCompress = cc.dopts.cp.Type() - cp = cc.dopts.cp - } - if c.creds != nil { - callHdr.Creds = c.creds - } - var trInfo traceInfo - if EnableTracing { - trInfo.tr = trace.New("grpc.Sent."+methodFamily(method), method) - trInfo.firstLine.client = true - if deadline, ok := ctx.Deadline(); ok { - trInfo.firstLine.deadline = deadline.Sub(time.Now()) - } - trInfo.tr.LazyLog(&trInfo.firstLine, false) - ctx = trace.NewContext(ctx, trInfo.tr) - defer func() { - if err != nil { - // Need to call tr.finish() if error is returned. - // Because tr will not be returned to caller. - trInfo.tr.LazyPrintf("RPC: [%v]", err) - trInfo.tr.SetError() - trInfo.tr.Finish() - } - }() - } - ctx = newContextWithRPCInfo(ctx, c.failFast) - sh := cc.dopts.copts.StatsHandler - var beginTime time.Time - if sh != nil { - ctx = sh.TagRPC(ctx, &stats.RPCTagInfo{FullMethodName: method, FailFast: c.failFast}) - beginTime = time.Now() - begin := &stats.Begin{ - Client: true, - BeginTime: beginTime, - FailFast: c.failFast, - } - sh.HandleRPC(ctx, begin) - defer func() { - if err != nil { - // Only handle end stats if err != nil. - end := &stats.End{ - Client: true, - Error: err, - BeginTime: beginTime, - EndTime: time.Now(), - } - sh.HandleRPC(ctx, end) - } - }() - } - - var ( - t transport.ClientTransport - s *transport.Stream - done func(balancer.DoneInfo) - ) - for { - // Check to make sure the context has expired. This will prevent us from - // looping forever if an error occurs for wait-for-ready RPCs where no data - // is sent on the wire. - select { - case <-ctx.Done(): - return nil, toRPCErr(ctx.Err()) - default: - } - - t, done, err = cc.getTransport(ctx, c.failFast) - if err != nil { - return nil, err - } - - s, err = t.NewStream(ctx, callHdr) - if err != nil { - if done != nil { - done(balancer.DoneInfo{Err: err}) - done = nil - } - // In the event of any error from NewStream, we never attempted to write - // anything to the wire, so we can retry indefinitely for non-fail-fast - // RPCs. - if !c.failFast { - continue - } - return nil, toRPCErr(err) - } - break - } - - cs := &clientStream{ - opts: opts, - c: c, - cc: cc, - desc: desc, - codec: c.codec, - cp: cp, - comp: comp, - cancel: cancel, - attempt: &csAttempt{ - t: t, - s: s, - p: &parser{r: s}, - done: done, - dc: cc.dopts.dc, - ctx: ctx, - trInfo: trInfo, - statsHandler: sh, - beginTime: beginTime, - }, - } - cs.c.stream = cs - cs.attempt.cs = cs - if desc != unaryStreamDesc { - // Listen on cc and stream contexts to cleanup when the user closes the - // ClientConn or cancels the stream context. In all other cases, an error - // should already be injected into the recv buffer by the transport, which - // the client will eventually receive, and then we will cancel the stream's - // context in clientStream.finish. - go func() { - select { - case <-cc.ctx.Done(): - cs.finish(ErrClientConnClosing) - case <-ctx.Done(): - cs.finish(toRPCErr(ctx.Err())) - } - }() - } - return cs, nil -} - -// clientStream implements a client side Stream. -type clientStream struct { - opts []CallOption - c *callInfo - cc *ClientConn - desc *StreamDesc - - codec baseCodec - cp Compressor - comp encoding.Compressor - - cancel context.CancelFunc // cancels all attempts - - sentLast bool // sent an end stream - - mu sync.Mutex // guards finished - finished bool // TODO: replace with atomic cmpxchg or sync.Once? - - attempt *csAttempt // the active client stream attempt - // TODO(hedging): hedging will have multiple attempts simultaneously. -} - -// csAttempt implements a single transport stream attempt within a -// clientStream. -type csAttempt struct { - cs *clientStream - t transport.ClientTransport - s *transport.Stream - p *parser - done func(balancer.DoneInfo) - - dc Decompressor - decomp encoding.Compressor - decompSet bool - - ctx context.Context // the application's context, wrapped by stats/tracing - - mu sync.Mutex // guards trInfo.tr - // trInfo.tr is set when created (if EnableTracing is true), - // and cleared when the finish method is called. - trInfo traceInfo - - statsHandler stats.Handler - beginTime time.Time -} - -func (cs *clientStream) Context() context.Context { - // TODO(retry): commit the current attempt (the context has peer-aware data). - return cs.attempt.context() -} - -func (cs *clientStream) Header() (metadata.MD, error) { - m, err := cs.attempt.header() - if err != nil { - // TODO(retry): maybe retry on error or commit attempt on success. - err = toRPCErr(err) - cs.finish(err) - } - return m, err -} - -func (cs *clientStream) Trailer() metadata.MD { - // TODO(retry): on error, maybe retry (trailers-only). - return cs.attempt.trailer() -} - -func (cs *clientStream) SendMsg(m interface{}) (err error) { - // TODO(retry): buffer message for replaying if not committed. - return cs.attempt.sendMsg(m) -} - -func (cs *clientStream) RecvMsg(m interface{}) (err error) { - // TODO(retry): maybe retry on error or commit attempt on success. - return cs.attempt.recvMsg(m) -} - -func (cs *clientStream) CloseSend() error { - cs.attempt.closeSend() - return nil -} - -func (cs *clientStream) finish(err error) { - if err == io.EOF { - // Ending a stream with EOF indicates a success. - err = nil - } - cs.mu.Lock() - if cs.finished { - cs.mu.Unlock() - return - } - cs.finished = true - cs.mu.Unlock() - if channelz.IsOn() { - if err != nil { - cs.cc.incrCallsFailed() - } else { - cs.cc.incrCallsSucceeded() - } - } - // TODO(retry): commit current attempt if necessary. - cs.attempt.finish(err) - for _, o := range cs.opts { - o.after(cs.c) - } - cs.cancel() -} - -func (a *csAttempt) context() context.Context { - return a.s.Context() -} - -func (a *csAttempt) header() (metadata.MD, error) { - return a.s.Header() -} - -func (a *csAttempt) trailer() metadata.MD { - return a.s.Trailer() -} - -func (a *csAttempt) sendMsg(m interface{}) (err error) { - // TODO Investigate how to signal the stats handling party. - // generate error stats if err != nil && err != io.EOF? - cs := a.cs - defer func() { - // For non-client-streaming RPCs, we return nil instead of EOF on success - // because the generated code requires it. finish is not called; RecvMsg() - // will call it with the stream's status independently. - if err == io.EOF && !cs.desc.ClientStreams { - err = nil - } - if err != nil && err != io.EOF { - // Call finish on the client stream for errors generated by this SendMsg - // call, as these indicate problems created by this client. (Transport - // errors are converted to an io.EOF error below; the real error will be - // returned from RecvMsg eventually in that case, or be retried.) - cs.finish(err) - } - }() - // TODO: Check cs.sentLast and error if we already ended the stream. - if EnableTracing { - a.mu.Lock() - if a.trInfo.tr != nil { - a.trInfo.tr.LazyLog(&payload{sent: true, msg: m}, true) - } - a.mu.Unlock() - } - data, err := encode(cs.codec, m) - if err != nil { - return err - } - compData, err := compress(data, cs.cp, cs.comp) - if err != nil { - return err - } - hdr, payload := msgHeader(data, compData) - // TODO(dfawley): should we be checking len(data) instead? - if len(payload) > *cs.c.maxSendMessageSize { - return status.Errorf(codes.ResourceExhausted, "trying to send message larger than max (%d vs. %d)", len(payload), *cs.c.maxSendMessageSize) - } - - if !cs.desc.ClientStreams { - cs.sentLast = true - } - err = a.t.Write(a.s, hdr, payload, &transport.Options{Last: !cs.desc.ClientStreams}) - if err == nil { - if a.statsHandler != nil { - a.statsHandler.HandleRPC(a.ctx, outPayload(true, m, data, payload, time.Now())) - } - if channelz.IsOn() { - a.t.IncrMsgSent() - } - return nil - } - return io.EOF -} - -func (a *csAttempt) recvMsg(m interface{}) (err error) { - cs := a.cs - defer func() { - if err != nil || !cs.desc.ServerStreams { - // err != nil or non-server-streaming indicates end of stream. - cs.finish(err) - } - }() - var inPayload *stats.InPayload - if a.statsHandler != nil { - inPayload = &stats.InPayload{ - Client: true, - } - } - if !a.decompSet { - // Block until we receive headers containing received message encoding. - if ct := a.s.RecvCompress(); ct != "" && ct != encoding.Identity { - if a.dc == nil || a.dc.Type() != ct { - // No configured decompressor, or it does not match the incoming - // message encoding; attempt to find a registered compressor that does. - a.dc = nil - a.decomp = encoding.GetCompressor(ct) - } - } else { - // No compression is used; disable our decompressor. - a.dc = nil - } - // Only initialize this state once per stream. - a.decompSet = true - } - err = recv(a.p, cs.codec, a.s, a.dc, m, *cs.c.maxReceiveMessageSize, inPayload, a.decomp) - if err != nil { - if err == io.EOF { - if statusErr := a.s.Status().Err(); statusErr != nil { - return statusErr - } - return io.EOF // indicates successful end of stream. - } - return toRPCErr(err) - } - if EnableTracing { - a.mu.Lock() - if a.trInfo.tr != nil { - a.trInfo.tr.LazyLog(&payload{sent: false, msg: m}, true) - } - a.mu.Unlock() - } - if inPayload != nil { - a.statsHandler.HandleRPC(a.ctx, inPayload) - } - if channelz.IsOn() { - a.t.IncrMsgRecv() - } - if cs.desc.ServerStreams { - // Subsequent messages should be received by subsequent RecvMsg calls. - return nil - } - - // Special handling for non-server-stream rpcs. - // This recv expects EOF or errors, so we don't collect inPayload. - err = recv(a.p, cs.codec, a.s, a.dc, m, *cs.c.maxReceiveMessageSize, nil, a.decomp) - if err == nil { - return toRPCErr(errors.New("grpc: client streaming protocol violation: get <nil>, want <EOF>")) - } - if err == io.EOF { - return a.s.Status().Err() // non-server streaming Recv returns nil on success - } - return toRPCErr(err) -} - -func (a *csAttempt) closeSend() { - cs := a.cs - if cs.sentLast { - return - } - cs.sentLast = true - cs.attempt.t.Write(cs.attempt.s, nil, nil, &transport.Options{Last: true}) - // We ignore errors from Write. Any error it would return would also be - // returned by a subsequent RecvMsg call, and the user is supposed to always - // finish the stream by calling RecvMsg until it returns err != nil. -} - -func (a *csAttempt) finish(err error) { - a.mu.Lock() - a.t.CloseStream(a.s, err) - - if a.done != nil { - a.done(balancer.DoneInfo{ - Err: err, - BytesSent: true, - BytesReceived: a.s.BytesReceived(), - }) - } - if a.statsHandler != nil { - end := &stats.End{ - Client: true, - BeginTime: a.beginTime, - EndTime: time.Now(), - Error: err, - } - a.statsHandler.HandleRPC(a.ctx, end) - } - if a.trInfo.tr != nil { - if err == nil { - a.trInfo.tr.LazyPrintf("RPC: [OK]") - } else { - a.trInfo.tr.LazyPrintf("RPC: [%v]", err) - a.trInfo.tr.SetError() - } - a.trInfo.tr.Finish() - a.trInfo.tr = nil - } - a.mu.Unlock() -} - -// ServerStream defines the interface a server stream has to satisfy. -type ServerStream interface { - // SetHeader sets the header metadata. It may be called multiple times. - // When call multiple times, all the provided metadata will be merged. - // All the metadata will be sent out when one of the following happens: - // - ServerStream.SendHeader() is called; - // - The first response is sent out; - // - An RPC status is sent out (error or success). - SetHeader(metadata.MD) error - // SendHeader sends the header metadata. - // The provided md and headers set by SetHeader() will be sent. - // It fails if called multiple times. - SendHeader(metadata.MD) error - // SetTrailer sets the trailer metadata which will be sent with the RPC status. - // When called more than once, all the provided metadata will be merged. - SetTrailer(metadata.MD) - Stream -} - -// serverStream implements a server side Stream. -type serverStream struct { - ctx context.Context - t transport.ServerTransport - s *transport.Stream - p *parser - codec baseCodec - - cp Compressor - dc Decompressor - comp encoding.Compressor - decomp encoding.Compressor - - maxReceiveMessageSize int - maxSendMessageSize int - trInfo *traceInfo - - statsHandler stats.Handler - - mu sync.Mutex // protects trInfo.tr after the service handler runs. -} - -func (ss *serverStream) Context() context.Context { - return ss.ctx -} - -func (ss *serverStream) SetHeader(md metadata.MD) error { - if md.Len() == 0 { - return nil - } - return ss.s.SetHeader(md) -} - -func (ss *serverStream) SendHeader(md metadata.MD) error { - return ss.t.WriteHeader(ss.s, md) -} - -func (ss *serverStream) SetTrailer(md metadata.MD) { - if md.Len() == 0 { - return - } - ss.s.SetTrailer(md) -} - -func (ss *serverStream) SendMsg(m interface{}) (err error) { - defer func() { - if ss.trInfo != nil { - ss.mu.Lock() - if ss.trInfo.tr != nil { - if err == nil { - ss.trInfo.tr.LazyLog(&payload{sent: true, msg: m}, true) - } else { - ss.trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true) - ss.trInfo.tr.SetError() - } - } - ss.mu.Unlock() - } - if err != nil && err != io.EOF { - st, _ := status.FromError(toRPCErr(err)) - ss.t.WriteStatus(ss.s, st) - } - if channelz.IsOn() && err == nil { - ss.t.IncrMsgSent() - } - }() - data, err := encode(ss.codec, m) - if err != nil { - return err - } - compData, err := compress(data, ss.cp, ss.comp) - if err != nil { - return err - } - hdr, payload := msgHeader(data, compData) - // TODO(dfawley): should we be checking len(data) instead? - if len(payload) > ss.maxSendMessageSize { - return status.Errorf(codes.ResourceExhausted, "trying to send message larger than max (%d vs. %d)", len(payload), ss.maxSendMessageSize) - } - if err := ss.t.Write(ss.s, hdr, payload, &transport.Options{Last: false}); err != nil { - return toRPCErr(err) - } - if ss.statsHandler != nil { - ss.statsHandler.HandleRPC(ss.s.Context(), outPayload(false, m, data, payload, time.Now())) - } - return nil -} - -func (ss *serverStream) RecvMsg(m interface{}) (err error) { - defer func() { - if ss.trInfo != nil { - ss.mu.Lock() - if ss.trInfo.tr != nil { - if err == nil { - ss.trInfo.tr.LazyLog(&payload{sent: false, msg: m}, true) - } else if err != io.EOF { - ss.trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true) - ss.trInfo.tr.SetError() - } - } - ss.mu.Unlock() - } - if err != nil && err != io.EOF { - st, _ := status.FromError(toRPCErr(err)) - ss.t.WriteStatus(ss.s, st) - } - if channelz.IsOn() && err == nil { - ss.t.IncrMsgRecv() - } - }() - var inPayload *stats.InPayload - if ss.statsHandler != nil { - inPayload = &stats.InPayload{} - } - if err := recv(ss.p, ss.codec, ss.s, ss.dc, m, ss.maxReceiveMessageSize, inPayload, ss.decomp); err != nil { - if err == io.EOF { - return err - } - if err == io.ErrUnexpectedEOF { - err = status.Errorf(codes.Internal, io.ErrUnexpectedEOF.Error()) - } - return toRPCErr(err) - } - if inPayload != nil { - ss.statsHandler.HandleRPC(ss.s.Context(), inPayload) - } - return nil -} - -// MethodFromServerStream returns the method string for the input stream. -// The returned string is in the format of "/service/method". -func MethodFromServerStream(stream ServerStream) (string, bool) { - return Method(stream.Context()) -} |