diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/internal/transport/transport.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/internal/transport/transport.go | 709 |
1 files changed, 0 insertions, 709 deletions
diff --git a/vendor/google.golang.org/grpc/internal/transport/transport.go b/vendor/google.golang.org/grpc/internal/transport/transport.go deleted file mode 100644 index 644cf11..0000000 --- a/vendor/google.golang.org/grpc/internal/transport/transport.go +++ /dev/null @@ -1,709 +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 transport defines and implements message oriented communication -// 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 - -import ( - "errors" - "fmt" - "io" - "net" - "sync" - "sync/atomic" - - "golang.org/x/net/context" - "google.golang.org/grpc/codes" - "google.golang.org/grpc/credentials" - "google.golang.org/grpc/keepalive" - "google.golang.org/grpc/metadata" - "google.golang.org/grpc/stats" - "google.golang.org/grpc/status" - "google.golang.org/grpc/tap" -) - -// recvMsg represents the received msg from the transport. All transport -// protocol specific info has been removed. -type recvMsg struct { - data []byte - // nil: received some data - // io.EOF: stream is completed. data is nil. - // other non-nil error: transport failure. data is nil. - err error -} - -// recvBuffer is an unbounded channel of recvMsg structs. -// Note recvBuffer differs from controlBuffer only in that recvBuffer -// holds a channel of only recvMsg structs instead of objects implementing "item" interface. -// recvBuffer is written to much more often than -// controlBuffer and using strict recvMsg structs helps avoid allocation in "recvBuffer.put" -type recvBuffer struct { - c chan recvMsg - mu sync.Mutex - backlog []recvMsg - err error -} - -func newRecvBuffer() *recvBuffer { - b := &recvBuffer{ - c: make(chan recvMsg, 1), - } - return b -} - -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: - b.mu.Unlock() - return - default: - } - } - b.backlog = append(b.backlog, r) - b.mu.Unlock() -} - -func (b *recvBuffer) load() { - b.mu.Lock() - if len(b.backlog) > 0 { - select { - case b.c <- b.backlog[0]: - b.backlog[0] = recvMsg{} - b.backlog = b.backlog[1:] - default: - } - } - b.mu.Unlock() -} - -// get returns the channel that receives a recvMsg in the buffer. -// -// Upon receipt of a recvMsg, the caller should call load to send another -// recvMsg onto the channel if there is any. -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 - 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 -// read additional data from recv. It blocks if there no additional data available -// in recv. If Read returns any non-nil error, it will continue to return that error. -func (r *recvBufferReader) Read(p []byte) (n int, err error) { - if r.err != nil { - return 0, r.err - } - n, r.err = r.read(p) - return n, r.err -} - -func (r *recvBufferReader) read(p []byte) (n int, err error) { - if r.last != nil && len(r.last) > 0 { - // Read remaining data left in last call. - copied := copy(p, r.last) - r.last = r.last[copied:] - return copied, nil - } - select { - case <-r.ctxDone: - return 0, ContextErr(r.ctx.Err()) - case m := <-r.recv.get(): - r.recv.load() - if m.err != nil { - return 0, m.err - } - copied := copy(p, m.data) - r.last = m.data[copied:] - return copied, nil - } -} - -type streamState uint32 - -const ( - streamActive streamState = iota - streamWriteDone // EndStream sent - streamReadDone // EndStream received - streamDone // the entire stream is finished. -) - -// Stream represents an RPC in the transport layer. -type Stream struct { - 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 - wq *writeQuota - - // Callback to state application's intentions to read data. This - // is used to adjust flow control, if needed. - requestRead func(int) - - 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. - - noHeaders bool // set if the client never received headers (set only after the stream is done). - - // 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 - - 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 -} - -// SetSendCompress sets the compression algorithm to the stream. -func (s *Stream) SetSendCompress(str string) { - s.sendCompress = str -} - -// Done returns a channel which is closed when it receives the final status -// from the server. -func (s *Stream) Done() <-chan struct{} { - return s.done -} - -// 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) { - 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: - } - return nil, err -} - -// TrailersOnly blocks until a header or trailers-only frame is received and -// then returns true if the stream was trailers-only. If the stream ends -// before headers are received, returns true, nil. If a context error happens -// first, returns it as a status error. Client-side only. -func (s *Stream) TrailersOnly() (bool, error) { - err := s.waitOnHeader() - if err != nil { - return false, err - } - // if !headerDone, some other connection error occurred. - return s.noHeaders && atomic.LoadUint32(&s.headerDone) == 1, nil -} - -// 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 { - c := s.trailer.Copy() - return c -} - -// 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 -} - -// Method returns the method for the stream. -func (s *Stream) Method() string { - return s.method -} - -// Status returns the status received from the server. -// Status can be read safely only after the stream has ended, -// that is, after Done() is closed. -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 { - if md.Len() == 0 { - return nil - } - if s.isHeaderSent() || s.getState() == streamDone { - return ErrIllegalHeaderWrite - } - s.hdrMu.Lock() - s.header = metadata.Join(s.header, md) - 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 { - return s.st.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 - } - if s.getState() == streamDone { - return ErrIllegalHeaderWrite - } - s.hdrMu.Lock() - s.trailer = metadata.Join(s.trailer, md) - s.hdrMu.Unlock() - return nil -} - -func (s *Stream) write(m recvMsg) { - s.buf.put(m) -} - -// Read reads all p bytes from the wire for this stream. -func (s *Stream) Read(p []byte) (n int, err error) { - // Don't request a read if there was an error earlier - if er := s.trReader.(*transportReader).er; er != nil { - return 0, er - } - s.requestRead(len(p)) - return io.ReadFull(s.trReader, p) -} - -// tranportReader reads all the data available for this Stream from the transport and -// passes them into the decoder, which converts them into a gRPC message stream. -// The error is io.EOF when the stream is done or another non-nil error if -// the stream broke. -type transportReader struct { - reader io.Reader - // The handler to control the window update procedure for both this - // particular stream and the associated transport. - windowHandler func(int) - er error -} - -func (t *transportReader) Read(p []byte) (n int, err error) { - n, err = t.reader.Read(p) - if err != nil { - t.er = err - return - } - t.windowHandler(n) - return -} - -// BytesReceived indicates whether any bytes have been received on this stream. -func (s *Stream) BytesReceived() bool { - 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 -// race when printing %#v. -func (s *Stream) GoString() string { - return fmt.Sprintf("<stream: %p, %v>", s, s.method) -} - -// state of transport -type transportState int - -const ( - reachable transportState = iota - closing - draining -) - -// ServerConfig consists of all the configurations to establish a server transport. -type ServerConfig struct { - MaxStreams uint32 - AuthInfo credentials.AuthInfo - InTapHandle tap.ServerInHandle - StatsHandler stats.Handler - KeepaliveParams keepalive.ServerParameters - KeepalivePolicy keepalive.EnforcementPolicy - InitialWindowSize int32 - InitialConnWindowSize int32 - WriteBufferSize int - ReadBufferSize int - ChannelzParentID int64 - MaxHeaderListSize *uint32 -} - -// NewServerTransport creates a ServerTransport with conn or non-nil error -// if it fails. -func NewServerTransport(protocol string, conn net.Conn, config *ServerConfig) (ServerTransport, error) { - return newHTTP2Server(conn, config) -} - -// ConnectOptions covers all relevant options for communicating with the server. -type ConnectOptions struct { - // UserAgent is the application user agent. - UserAgent string - // Dialer specifies how to dial a network address. - Dialer func(context.Context, string) (net.Conn, error) - // FailOnNonTempDialError specifies if gRPC fails on non-temporary dial errors. - FailOnNonTempDialError bool - // PerRPCCredentials stores the PerRPCCredentials required to issue RPCs. - PerRPCCredentials []credentials.PerRPCCredentials - // TransportCredentials stores the Authenticator required to setup a client connection. - TransportCredentials credentials.TransportCredentials - // KeepaliveParams stores the keepalive parameters. - KeepaliveParams keepalive.ClientParameters - // StatsHandler stores the handler for stats. - StatsHandler stats.Handler - // InitialWindowSize sets the initial window size for a stream. - InitialWindowSize int32 - // InitialConnWindowSize sets the initial window size for a connection. - InitialConnWindowSize int32 - // WriteBufferSize sets the size of write buffer which in turn determines how much data can be batched before it's written on the wire. - 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 - // MaxHeaderListSize sets the max (uncompressed) size of header list that is prepared to be received. - MaxHeaderListSize *uint32 -} - -// TargetInfo contains the information of the target such as network address and metadata. -type TargetInfo struct { - Addr string - Metadata interface{} - Authority string -} - -// NewClientTransport establishes the transport with the required ConnectOptions -// and returns it to the caller. -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 -// transmission. -type Options struct { - // Last indicates whether this write is the last piece for - // this stream. - Last bool -} - -// CallHdr carries the information of a particular RPC. -type CallHdr struct { - // Host specifies the peer's host. - Host string - - // Method specifies the operation to perform. - Method string - - // SendCompress specifies the compression algorithm applied on - // outbound message. - SendCompress string - - // Creds specifies credentials.PerRPCCredentials for a call. - Creds credentials.PerRPCCredentials - - // 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 - - PreviousAttempts int // value of grpc-previous-rpc-attempts header to set -} - -// ClientTransport is the common interface for all gRPC client-side transport -// implementations. -type ClientTransport interface { - // Close tears down this transport. Once it returns, the transport - // should not be accessed any more. The caller must make sure this - // is called only once. - Close() error - - // GracefulClose starts to tear down the transport. It stops accepting - // new RPCs and wait the completion of the pending RPCs. - GracefulClose() error - - // Write sends the data for the given stream. A nil stream indicates - // the write is to be performed on the transport as a whole. - Write(s *Stream, hdr []byte, data []byte, opts *Options) error - - // NewStream creates a Stream for an RPC. - NewStream(ctx context.Context, callHdr *CallHdr) (*Stream, error) - - // CloseStream clears the footprint of a stream when the stream is - // not needed any more. The err indicates the error incurred when - // CloseStream is called. Must be called when a stream is finished - // unless the associated transport is closing. - CloseStream(stream *Stream, err error) - - // Error returns a channel that is closed when some I/O error - // happens. Typically the caller should have a goroutine to monitor - // this in order to take action (e.g., close the current transport - // and create a new one) in error case. It should not return nil - // once the transport is initiated. - Error() <-chan struct{} - - // GoAway returns a channel that is closed when ClientTransport - // receives the draining signal from the server (e.g., GOAWAY frame in - // HTTP/2). - GoAway() <-chan struct{} - - // 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 -// implementations. -// -// Methods may be called concurrently from multiple goroutines, but -// Write methods for a given Stream will be called serially. -type ServerTransport interface { - // HandleStreams receives incoming streams using the given handler. - HandleStreams(func(*Stream), func(context.Context, string) context.Context) - - // WriteHeader sends the header metadata for the given stream. - // WriteHeader may not be called on all streams. - WriteHeader(s *Stream, md metadata.MD) error - - // Write sends the data for the given stream. - // Write may not be called on all streams. - Write(s *Stream, hdr []byte, data []byte, opts *Options) error - - // WriteStatus sends the status of a stream to the client. WriteStatus is - // the final call made on a stream and always occurs. - WriteStatus(s *Stream, st *status.Status) error - - // Close tears down the transport. Once it is called, the transport - // should not be accessed any more. All the pending streams and their - // handlers will be terminated asynchronously. - Close() error - - // RemoteAddr returns the remote network address. - RemoteAddr() net.Addr - - // 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() -} - -// connectionErrorf creates an ConnectionError with the specified error description. -func connectionErrorf(temp bool, e error, format string, a ...interface{}) ConnectionError { - return ConnectionError{ - Desc: fmt.Sprintf(format, a...), - temp: temp, - err: e, - } -} - -// ConnectionError is an error that results in the termination of the -// entire connection and the retry of all the active streams. -type ConnectionError struct { - Desc string - temp bool - err error -} - -func (e ConnectionError) Error() string { - return fmt.Sprintf("connection error: desc = %q", e.Desc) -} - -// Temporary indicates if this connection error is temporary or fatal. -func (e ConnectionError) Temporary() bool { - return e.temp -} - -// Origin returns the original error of this connection error. -func (e ConnectionError) Origin() error { - // Never return nil error here. - // If the original error is nil, return itself. - if e.err == nil { - return e - } - return e.err -} - -var ( - // ErrConnClosing indicates that the transport is closing. - ErrConnClosing = connectionErrorf(true, nil, "transport is closing") - // errStreamDrain indicates that the stream is rejected because the - // connection is draining. This could be caused by goaway or balancer - // removing the address. - errStreamDrain = status.Error(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") -) - -// GoAwayReason contains the reason for the GoAway frame received. -type GoAwayReason uint8 - -const ( - // 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 -) - -// channelzData is used to store channelz related data for http2Client and http2Server. -// These fields cannot be embedded in the original structs (e.g. http2Client), since to do atomic -// operation on int64 variable on 32-bit machine, user is responsible to enforce memory alignment. -// Here, by grouping those int64 fields inside a struct, we are enforcing the alignment. -type channelzData struct { - kpCount int64 - // The number of streams that have started, including already finished ones. - streamsStarted int64 - // Client side: The number of streams that have ended successfully by receiving - // EoS bit set frame from server. - // Server side: The number of streams that have ended successfully by sending - // frame with EoS bit set. - streamsSucceeded int64 - streamsFailed int64 - // lastStreamCreatedTime stores the timestamp that the last stream gets created. It is of int64 type - // instead of time.Time since it's more costly to atomically update time.Time variable than int64 - // variable. The same goes for lastMsgSentTime and lastMsgRecvTime. - lastStreamCreatedTime int64 - msgSent int64 - msgRecv int64 - lastMsgSentTime int64 - lastMsgRecvTime int64 -} |