diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/transport/transport.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/transport/transport.go | 438 |
1 files changed, 182 insertions, 256 deletions
diff --git a/vendor/google.golang.org/grpc/transport/transport.go b/vendor/google.golang.org/grpc/transport/transport.go index 2cf9bd3..f51f878 100644 --- a/vendor/google.golang.org/grpc/transport/transport.go +++ b/vendor/google.golang.org/grpc/transport/transport.go @@ -17,19 +17,19 @@ */ // Package transport defines and implements message oriented communication -// channel to complete various transactions (e.g., an RPC). -package transport // import "google.golang.org/grpc/transport" +// channel to complete various transactions (e.g., an RPC). It is meant for +// grpc-internal usage and is not intended to be imported directly by users. +package transport // externally used as import "google.golang.org/grpc/transport" import ( - stdctx "context" + "errors" "fmt" "io" "net" "sync" - "time" + "sync/atomic" "golang.org/x/net/context" - "golang.org/x/net/http2" "google.golang.org/grpc/codes" "google.golang.org/grpc/credentials" "google.golang.org/grpc/keepalive" @@ -58,6 +58,7 @@ type recvBuffer struct { c chan recvMsg mu sync.Mutex backlog []recvMsg + err error } func newRecvBuffer() *recvBuffer { @@ -69,6 +70,13 @@ func newRecvBuffer() *recvBuffer { func (b *recvBuffer) put(r recvMsg) { b.mu.Lock() + if b.err != nil { + b.mu.Unlock() + // An error had occurred earlier, don't accept more + // data or errors. + return + } + b.err = r.err if len(b.backlog) == 0 { select { case b.c <- r: @@ -102,14 +110,15 @@ func (b *recvBuffer) get() <-chan recvMsg { return b.c } +// // recvBufferReader implements io.Reader interface to read the data from // recvBuffer. type recvBufferReader struct { - ctx context.Context - goAway chan struct{} - recv *recvBuffer - last []byte // Stores the remaining data in the previous calls. - err error + ctx context.Context + ctxDone <-chan struct{} // cache of ctx.Done() (for performance). + recv *recvBuffer + last []byte // Stores the remaining data in the previous calls. + err error } // Read reads the next len(p) bytes from last. If last is drained, it tries to @@ -131,10 +140,8 @@ func (r *recvBufferReader) read(p []byte) (n int, err error) { return copied, nil } select { - case <-r.ctx.Done(): + case <-r.ctxDone: return 0, ContextErr(r.ctx.Err()) - case <-r.goAway: - return 0, ErrStreamDrain case m := <-r.recv.get(): r.recv.load() if m.err != nil { @@ -146,61 +153,7 @@ func (r *recvBufferReader) read(p []byte) (n int, err error) { } } -// All items in an out of a controlBuffer should be the same type. -type item interface { - item() -} - -// controlBuffer is an unbounded channel of item. -type controlBuffer struct { - c chan item - mu sync.Mutex - backlog []item -} - -func newControlBuffer() *controlBuffer { - b := &controlBuffer{ - c: make(chan item, 1), - } - return b -} - -func (b *controlBuffer) put(r item) { - b.mu.Lock() - if len(b.backlog) == 0 { - select { - case b.c <- r: - b.mu.Unlock() - return - default: - } - } - b.backlog = append(b.backlog, r) - b.mu.Unlock() -} - -func (b *controlBuffer) load() { - b.mu.Lock() - if len(b.backlog) > 0 { - select { - case b.c <- b.backlog[0]: - b.backlog[0] = nil - b.backlog = b.backlog[1:] - default: - } - } - b.mu.Unlock() -} - -// get returns the channel that receives an item in the buffer. -// -// Upon receipt of an item, the caller should call load to send another -// item onto the channel if there is any. -func (b *controlBuffer) get() <-chan item { - return b.c -} - -type streamState uint8 +type streamState uint32 const ( streamActive streamState = iota @@ -211,66 +164,93 @@ const ( // Stream represents an RPC in the transport layer. type Stream struct { - id uint32 - // nil for client side Stream. - st ServerTransport - // ctx is the associated context of the stream. - ctx context.Context - // cancel is always nil for client side Stream. - cancel context.CancelFunc - // done is closed when the final status arrives. - done chan struct{} - // goAway is closed when the server sent GoAways signal before this stream was initiated. - goAway chan struct{} - // method records the associated RPC method of the stream. - method string + id uint32 + st ServerTransport // nil for client side Stream + ctx context.Context // the associated context of the stream + cancel context.CancelFunc // always nil for client side Stream + done chan struct{} // closed at the end of stream to unblock writers. On the client side. + ctxDone <-chan struct{} // same as done chan but for server side. Cache of ctx.Done() (for performance) + method string // the associated RPC method of the stream recvCompress string sendCompress string buf *recvBuffer trReader io.Reader fc *inFlow recvQuota uint32 - - // TODO: Remote this unused variable. - // The accumulated inbound quota pending for window update. - updateQuota uint32 + wq *writeQuota // Callback to state application's intentions to read data. This - // is used to adjust flow control, if need be. + // is used to adjust flow control, if needed. requestRead func(int) - sendQuotaPool *quotaPool - localSendQuota *quotaPool - // Close headerChan to indicate the end of reception of header metadata. - headerChan chan struct{} - // header caches the received header metadata. - header metadata.MD - // The key-value map of trailer metadata. - trailer metadata.MD - - mu sync.RWMutex // guard the following - // headerOK becomes true from the first header is about to send. - headerOk bool - state streamState - // true iff headerChan is closed. Used to avoid closing headerChan - // multiple times. - headerDone bool - // the status error received from the server. + headerChan chan struct{} // closed to indicate the end of header metadata. + headerDone uint32 // set when headerChan is closed. Used to avoid closing headerChan multiple times. + + // hdrMu protects header and trailer metadata on the server-side. + hdrMu sync.Mutex + header metadata.MD // the received header metadata. + trailer metadata.MD // the key-value map of trailer metadata. + + // On the server-side, headerSent is atomically set to 1 when the headers are sent out. + headerSent uint32 + + state streamState + + // On client-side it is the status error received from the server. + // On server-side it is unused. status *status.Status - // rstStream indicates whether a RST_STREAM frame needs to be sent - // to the server to signify that this stream is closing. - rstStream bool - // rstError is the error that needs to be sent along with the RST_STREAM frame. - rstError http2.ErrCode - // bytesSent and bytesReceived indicates whether any bytes have been sent or - // received on this stream. - bytesSent bool - bytesReceived bool + + bytesReceived uint32 // indicates whether any bytes have been received on this stream + unprocessed uint32 // set if the server sends a refused stream or GOAWAY including this stream + + // contentSubtype is the content-subtype for requests. + // this must be lowercase or the behavior is undefined. + contentSubtype string +} + +// isHeaderSent is only valid on the server-side. +func (s *Stream) isHeaderSent() bool { + return atomic.LoadUint32(&s.headerSent) == 1 +} + +// updateHeaderSent updates headerSent and returns true +// if it was alreay set. It is valid only on server-side. +func (s *Stream) updateHeaderSent() bool { + return atomic.SwapUint32(&s.headerSent, 1) == 1 +} + +func (s *Stream) swapState(st streamState) streamState { + return streamState(atomic.SwapUint32((*uint32)(&s.state), uint32(st))) +} + +func (s *Stream) compareAndSwapState(oldState, newState streamState) bool { + return atomic.CompareAndSwapUint32((*uint32)(&s.state), uint32(oldState), uint32(newState)) +} + +func (s *Stream) getState() streamState { + return streamState(atomic.LoadUint32((*uint32)(&s.state))) +} + +func (s *Stream) waitOnHeader() error { + if s.headerChan == nil { + // On the server headerChan is always nil since a stream originates + // only after having received headers. + return nil + } + select { + case <-s.ctx.Done(): + return ContextErr(s.ctx.Err()) + case <-s.headerChan: + return nil + } } // RecvCompress returns the compression algorithm applied to the inbound // message. It is empty string if there is no compression applied. func (s *Stream) RecvCompress() string { + if err := s.waitOnHeader(); err != nil { + return "" + } return s.recvCompress } @@ -285,28 +265,17 @@ func (s *Stream) Done() <-chan struct{} { return s.done } -// GoAway returns a channel which is closed when the server sent GoAways signal -// before this stream was initiated. -func (s *Stream) GoAway() <-chan struct{} { - return s.goAway -} - // Header acquires the key-value pairs of header metadata once it // is available. It blocks until i) the metadata is ready or ii) there is no // header metadata or iii) the stream is canceled/expired. func (s *Stream) Header() (metadata.MD, error) { - var err error - select { - case <-s.ctx.Done(): - err = ContextErr(s.ctx.Err()) - case <-s.goAway: - err = ErrStreamDrain - case <-s.headerChan: - return s.header.Copy(), nil - } + err := s.waitOnHeader() // Even if the stream is closed, header is returned if available. select { case <-s.headerChan: + if s.header == nil { + return nil, nil + } return s.header.Copy(), nil default: } @@ -316,10 +285,10 @@ func (s *Stream) Header() (metadata.MD, error) { // Trailer returns the cached trailer metedata. Note that if it is not called // after the entire stream is done, it could return an empty MD. Client // side only. +// It can be safely read only after stream has ended that is either read +// or write have returned io.EOF. func (s *Stream) Trailer() metadata.MD { - s.mu.RLock() c := s.trailer.Copy() - s.mu.RUnlock() return c } @@ -329,6 +298,15 @@ func (s *Stream) ServerTransport() ServerTransport { return s.st } +// ContentSubtype returns the content-subtype for a request. For example, a +// content-subtype of "proto" will result in a content-type of +// "application/grpc+proto". This will always be lowercase. See +// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for +// more details. +func (s *Stream) ContentSubtype() string { + return s.contentSubtype +} + // Context returns the context of the stream. func (s *Stream) Context() context.Context { return s.ctx @@ -340,36 +318,49 @@ func (s *Stream) Method() string { } // Status returns the status received from the server. +// Status can be read safely only after the stream has ended, +// that is, read or write has returned io.EOF. func (s *Stream) Status() *status.Status { return s.status } // SetHeader sets the header metadata. This can be called multiple times. // Server side only. +// This should not be called in parallel to other data writes. func (s *Stream) SetHeader(md metadata.MD) error { - s.mu.Lock() - if s.headerOk || s.state == streamDone { - s.mu.Unlock() - return ErrIllegalHeaderWrite - } if md.Len() == 0 { - s.mu.Unlock() return nil } + if s.isHeaderSent() || s.getState() == streamDone { + return ErrIllegalHeaderWrite + } + s.hdrMu.Lock() s.header = metadata.Join(s.header, md) - s.mu.Unlock() + s.hdrMu.Unlock() return nil } +// SendHeader sends the given header metadata. The given metadata is +// combined with any metadata set by previous calls to SetHeader and +// then written to the transport stream. +func (s *Stream) SendHeader(md metadata.MD) error { + t := s.ServerTransport() + return t.WriteHeader(s, md) +} + // SetTrailer sets the trailer metadata which will be sent with the RPC status // by the server. This can be called multiple times. Server side only. +// This should not be called parallel to other data writes. func (s *Stream) SetTrailer(md metadata.MD) error { if md.Len() == 0 { return nil } - s.mu.Lock() + if s.getState() == streamDone { + return ErrIllegalHeaderWrite + } + s.hdrMu.Lock() s.trailer = metadata.Join(s.trailer, md) - s.mu.Unlock() + s.hdrMu.Unlock() return nil } @@ -409,28 +400,15 @@ func (t *transportReader) Read(p []byte) (n int, err error) { return } -// finish sets the stream's state and status, and closes the done channel. -// s.mu must be held by the caller. st must always be non-nil. -func (s *Stream) finish(st *status.Status) { - s.status = st - s.state = streamDone - close(s.done) -} - -// BytesSent indicates whether any bytes have been sent on this stream. -func (s *Stream) BytesSent() bool { - s.mu.Lock() - bs := s.bytesSent - s.mu.Unlock() - return bs -} - // BytesReceived indicates whether any bytes have been received on this stream. func (s *Stream) BytesReceived() bool { - s.mu.Lock() - br := s.bytesReceived - s.mu.Unlock() - return br + return atomic.LoadUint32(&s.bytesReceived) == 1 +} + +// Unprocessed indicates whether the server did not process this stream -- +// i.e. it sent a refused stream or GOAWAY including this stream ID. +func (s *Stream) Unprocessed() bool { + return atomic.LoadUint32(&s.unprocessed) == 1 } // GoString is implemented by Stream so context.String() won't @@ -439,21 +417,6 @@ func (s *Stream) GoString() string { return fmt.Sprintf("<stream: %p, %v>", s, s.method) } -// The key to save transport.Stream in the context. -type streamKey struct{} - -// newContextWithStream creates a new context from ctx and attaches stream -// to it. -func newContextWithStream(ctx context.Context, stream *Stream) context.Context { - return context.WithValue(ctx, streamKey{}, stream) -} - -// StreamFromContext returns the stream saved in ctx. -func StreamFromContext(ctx context.Context) (s *Stream, ok bool) { - s, ok = ctx.Value(streamKey{}).(*Stream) - return -} - // state of transport type transportState int @@ -475,6 +438,7 @@ type ServerConfig struct { InitialConnWindowSize int32 WriteBufferSize int ReadBufferSize int + ChannelzParentID int64 } // NewServerTransport creates a ServerTransport with conn or non-nil error @@ -510,18 +474,21 @@ type ConnectOptions struct { WriteBufferSize int // ReadBufferSize sets the size of read buffer, which in turn determines how much data can be read at most for one read syscall. ReadBufferSize int + // ChannelzParentID sets the addrConn id which initiate the creation of this client transport. + ChannelzParentID int64 } // TargetInfo contains the information of the target such as network address and metadata. type TargetInfo struct { - Addr string - Metadata interface{} + Addr string + Metadata interface{} + Authority string } // NewClientTransport establishes the transport with the required ConnectOptions // and returns it to the caller. -func NewClientTransport(ctx context.Context, target TargetInfo, opts ConnectOptions, timeout time.Duration) (ClientTransport, error) { - return newHTTP2Client(ctx, target, opts, timeout) +func NewClientTransport(connectCtx, ctx context.Context, target TargetInfo, opts ConnectOptions, onSuccess func()) (ClientTransport, error) { + return newHTTP2Client(connectCtx, ctx, target, opts, onSuccess) } // Options provides additional hints and information for message @@ -545,10 +512,6 @@ type CallHdr struct { // Method specifies the operation to perform. Method string - // RecvCompress specifies the compression algorithm applied on - // inbound messages. - RecvCompress string - // SendCompress specifies the compression algorithm applied on // outbound message. SendCompress string @@ -563,6 +526,14 @@ type CallHdr struct { // for performance purposes. // If it's false, new stream will never be flushed. Flush bool + + // ContentSubtype specifies the content-subtype for a request. For example, a + // content-subtype of "proto" will result in a content-type of + // "application/grpc+proto". The value of ContentSubtype must be all + // lowercase, otherwise the behavior is undefined. See + // https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests + // for more details. + ContentSubtype string } // ClientTransport is the common interface for all gRPC client-side transport @@ -604,6 +575,12 @@ type ClientTransport interface { // GetGoAwayReason returns the reason why GoAway frame was received. GetGoAwayReason() GoAwayReason + + // IncrMsgSent increments the number of message sent through this transport. + IncrMsgSent() + + // IncrMsgRecv increments the number of message received through this transport. + IncrMsgRecv() } // ServerTransport is the common interface for all gRPC server-side transport @@ -637,6 +614,12 @@ type ServerTransport interface { // Drain notifies the client this ServerTransport stops accepting new RPCs. Drain() + + // IncrMsgSent increments the number of message sent through this transport. + IncrMsgSent() + + // IncrMsgRecv increments the number of message received through this transport. + IncrMsgRecv() } // streamErrorf creates an StreamError with the specified error code and description. @@ -686,9 +669,16 @@ func (e ConnectionError) Origin() error { var ( // ErrConnClosing indicates that the transport is closing. ErrConnClosing = connectionErrorf(true, nil, "transport is closing") - // ErrStreamDrain indicates that the stream is rejected by the server because - // the server stops accepting new RPCs. - ErrStreamDrain = streamErrorf(codes.Unavailable, "the server stops accepting new RPCs") + // errStreamDrain indicates that the stream is rejected because the + // connection is draining. This could be caused by goaway or balancer + // removing the address. + errStreamDrain = streamErrorf(codes.Unavailable, "the connection is draining") + // errStreamDone is returned from write at the client side to indiacte application + // layer of an error. + errStreamDone = errors.New("the stream is done") + // StatusGoAway indicates that the server sent a GOAWAY that included this + // stream's ID in unprocessed RPCs. + statusGoAway = status.New(codes.Unavailable, "the stream is rejected because server is draining the connection") ) // TODO: See if we can replace StreamError with status package errors. @@ -703,80 +693,16 @@ func (e StreamError) Error() string { return fmt.Sprintf("stream error: code = %s desc = %q", e.Code, e.Desc) } -// wait blocks until it can receive from one of the provided contexts or -// channels. ctx is the context of the RPC, tctx is the context of the -// transport, done is a channel closed to indicate the end of the RPC, goAway -// is a channel closed to indicate a GOAWAY was received, and proceed is a -// quota channel, whose received value is returned from this function if none -// of the other signals occur first. -func wait(ctx, tctx context.Context, done, goAway <-chan struct{}, proceed <-chan int) (int, error) { - select { - case <-ctx.Done(): - return 0, ContextErr(ctx.Err()) - case <-done: - return 0, io.EOF - case <-goAway: - return 0, ErrStreamDrain - case <-tctx.Done(): - return 0, ErrConnClosing - case i := <-proceed: - return i, nil - } -} - -// ContextErr converts the error from context package into a StreamError. -func ContextErr(err error) StreamError { - switch err { - case context.DeadlineExceeded, stdctx.DeadlineExceeded: - return streamErrorf(codes.DeadlineExceeded, "%v", err) - case context.Canceled, stdctx.Canceled: - return streamErrorf(codes.Canceled, "%v", err) - } - return streamErrorf(codes.Internal, "Unexpected error from context packet: %v", err) -} - // GoAwayReason contains the reason for the GoAway frame received. type GoAwayReason uint8 const ( - // Invalid indicates that no GoAway frame is received. - Invalid GoAwayReason = 0 - // NoReason is the default value when GoAway frame is received. - NoReason GoAwayReason = 1 - // TooManyPings indicates that a GoAway frame with ErrCodeEnhanceYourCalm - // was received and that the debug data said "too_many_pings". - TooManyPings GoAwayReason = 2 + // GoAwayInvalid indicates that no GoAway frame is received. + GoAwayInvalid GoAwayReason = 0 + // GoAwayNoReason is the default value when GoAway frame is received. + GoAwayNoReason GoAwayReason = 1 + // GoAwayTooManyPings indicates that a GoAway frame with + // ErrCodeEnhanceYourCalm was received and that the debug data said + // "too_many_pings". + GoAwayTooManyPings GoAwayReason = 2 ) - -// loopyWriter is run in a separate go routine. It is the single code path that will -// write data on wire. -func loopyWriter(ctx context.Context, cbuf *controlBuffer, handler func(item) error) { - for { - select { - case i := <-cbuf.get(): - cbuf.load() - if err := handler(i); err != nil { - return - } - case <-ctx.Done(): - return - } - hasData: - for { - select { - case i := <-cbuf.get(): - cbuf.load() - if err := handler(i); err != nil { - return - } - case <-ctx.Done(): - return - default: - if err := handler(&flushIO{}); err != nil { - return - } - break hasData - } - } - } -} |