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Diffstat (limited to 'vendor/google.golang.org/grpc/transport/transport.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/transport/transport.go | 595 |
1 files changed, 0 insertions, 595 deletions
diff --git a/vendor/google.golang.org/grpc/transport/transport.go b/vendor/google.golang.org/grpc/transport/transport.go deleted file mode 100644 index 413f7493b..000000000 --- a/vendor/google.golang.org/grpc/transport/transport.go +++ /dev/null @@ -1,595 +0,0 @@ -/* - * - * 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 defines and implements message oriented communication channel -to complete various transactions (e.g., an RPC). -*/ -package transport // import "google.golang.org/grpc/transport" - -import ( - "bytes" - "fmt" - "io" - "net" - "sync" - - "golang.org/x/net/context" - "golang.org/x/net/trace" - "google.golang.org/grpc/codes" - "google.golang.org/grpc/credentials" - "google.golang.org/grpc/metadata" -) - -// 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 -} - -func (*recvMsg) item() {} - -// All items in an out of a recvBuffer should be the same type. -type item interface { - item() -} - -// recvBuffer is an unbounded channel of item. -type recvBuffer struct { - c chan item - mu sync.Mutex - backlog []item -} - -func newRecvBuffer() *recvBuffer { - b := &recvBuffer{ - c: make(chan item, 1), - } - return b -} - -func (b *recvBuffer) put(r item) { - b.mu.Lock() - defer b.mu.Unlock() - if len(b.backlog) == 0 { - select { - case b.c <- r: - return - default: - } - } - b.backlog = append(b.backlog, r) -} - -func (b *recvBuffer) load() { - b.mu.Lock() - defer b.mu.Unlock() - if len(b.backlog) > 0 { - select { - case b.c <- b.backlog[0]: - b.backlog = b.backlog[1:] - default: - } - } -} - -// 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 *recvBuffer) get() <-chan item { - 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 *bytes.Reader // 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 - } - defer func() { r.err = err }() - if r.last != nil && r.last.Len() > 0 { - // Read remaining data left in last call. - return r.last.Read(p) - } - select { - case <-r.ctx.Done(): - return 0, ContextErr(r.ctx.Err()) - case <-r.goAway: - return 0, ErrStreamDrain - case i := <-r.recv.get(): - r.recv.load() - m := i.(*recvMsg) - if m.err != nil { - return 0, m.err - } - r.last = bytes.NewReader(m.data) - return r.last.Read(p) - } -} - -type streamState uint8 - -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 - // 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 - recvCompress string - sendCompress string - buf *recvBuffer - dec io.Reader - fc *inFlow - recvQuota uint32 - // The accumulated inbound quota pending for window update. - updateQuota uint32 - // The handler to control the window update procedure for both this - // particular stream and the associated transport. - windowHandler func(int) - - sendQuotaPool *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 received from the server. - statusCode codes.Code - statusDesc string -} - -// 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 { - return s.recvCompress -} - -// SetSendCompress sets the compression algorithm to the stream. -func (s *Stream) SetSendCompress(str string) { - s.sendCompress = str -} - -// Done returns a chanel which is closed when it receives the final status -// from the server. -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 cancelled/expired. -func (s *Stream) Header() (metadata.MD, error) { - select { - case <-s.ctx.Done(): - return nil, ContextErr(s.ctx.Err()) - case <-s.goAway: - return nil, ErrStreamDrain - case <-s.headerChan: - return s.header.Copy(), 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. -func (s *Stream) Trailer() metadata.MD { - s.mu.RLock() - defer s.mu.RUnlock() - return s.trailer.Copy() -} - -// ServerTransport returns the underlying ServerTransport for the stream. -// The client side stream always returns nil. -func (s *Stream) ServerTransport() ServerTransport { - return s.st -} - -// Context returns the context of the stream. -func (s *Stream) Context() context.Context { - return s.ctx -} - -// TraceContext recreates the context of s with a trace.Trace. -func (s *Stream) TraceContext(tr trace.Trace) { - s.ctx = trace.NewContext(s.ctx, tr) -} - -// Method returns the method for the stream. -func (s *Stream) Method() string { - return s.method -} - -// StatusCode returns statusCode received from the server. -func (s *Stream) StatusCode() codes.Code { - return s.statusCode -} - -// StatusDesc returns statusDesc received from the server. -func (s *Stream) StatusDesc() string { - return s.statusDesc -} - -// SetHeader sets the header metadata. This can be called multiple times. -// Server side only. -func (s *Stream) SetHeader(md metadata.MD) error { - s.mu.Lock() - defer s.mu.Unlock() - if s.headerOk || s.state == streamDone { - return ErrIllegalHeaderWrite - } - if md.Len() == 0 { - return nil - } - s.header = metadata.Join(s.header, md) - return nil -} - -// 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. -func (s *Stream) SetTrailer(md metadata.MD) error { - if md.Len() == 0 { - return nil - } - s.mu.Lock() - defer s.mu.Unlock() - s.trailer = metadata.Join(s.trailer, md) - return nil -} - -func (s *Stream) write(m recvMsg) { - s.buf.put(&m) -} - -// Read 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. -func (s *Stream) Read(p []byte) (n int, err error) { - n, err = s.dec.Read(p) - if err != nil { - return - } - s.windowHandler(n) - return -} - -// 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 - -const ( - reachable transportState = iota - unreachable - closing - draining -) - -// NewServerTransport creates a ServerTransport with conn or non-nil error -// if it fails. -func NewServerTransport(protocol string, conn net.Conn, maxStreams uint32, authInfo credentials.AuthInfo) (ServerTransport, error) { - return newHTTP2Server(conn, maxStreams, authInfo) -} - -// 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) - // PerRPCCredentials stores the PerRPCCredentials required to issue RPCs. - PerRPCCredentials []credentials.PerRPCCredentials - // TransportCredentials stores the Authenticator required to setup a client connection. - TransportCredentials credentials.TransportCredentials -} - -// TargetInfo contains the information of the target such as network address and metadata. -type TargetInfo struct { - Addr string - Metadata interface{} -} - -// NewClientTransport establishes the transport with the required ConnectOptions -// and returns it to the caller. -func NewClientTransport(ctx context.Context, target TargetInfo, opts ConnectOptions) (ClientTransport, error) { - return newHTTP2Client(ctx, target, opts) -} - -// 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 - - // Delay is a hint to the transport implementation for whether - // the data could be buffered for a batching write. The - // Transport implementation may ignore the hint. - Delay 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 - - // RecvCompress specifies the compression algorithm applied on - // inbound messages. - RecvCompress string - - // SendCompress specifies the compression algorithm applied on - // outbound message. - SendCompress string - - // Flush indicates whether a new stream command should be sent - // to the peer without waiting for the first data. This is - // only a hint. The transport may modify the flush decision - // for performance purposes. - Flush bool -} - -// 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, 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 ClientTranspor - // receives the draining signal from the server (e.g., GOAWAY frame in - // HTTP/2). - GoAway() <-chan struct{} -} - -// 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)) - - // 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, 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, statusCode codes.Code, statusDesc string) 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() -} - -// streamErrorf creates an StreamError with the specified error code and description. -func streamErrorf(c codes.Code, format string, a ...interface{}) StreamError { - return StreamError{ - Code: c, - Desc: fmt.Sprintf(format, a...), - } -} - -// 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 by the server because - // the server stops accepting new RPCs. - ErrStreamDrain = streamErrorf(codes.Unavailable, "the server stops accepting new RPCs") -) - -// StreamError is an error that only affects one stream within a connection. -type StreamError struct { - Code codes.Code - Desc string -} - -func (e StreamError) Error() string { - return fmt.Sprintf("stream error: code = %d desc = %q", e.Code, e.Desc) -} - -// ContextErr converts the error from context package into a StreamError. -func ContextErr(err error) StreamError { - switch err { - case context.DeadlineExceeded: - return streamErrorf(codes.DeadlineExceeded, "%v", err) - case context.Canceled: - return streamErrorf(codes.Canceled, "%v", err) - } - panic(fmt.Sprintf("Unexpected error from context packet: %v", err)) -} - -// wait blocks until it can receive from ctx.Done, closing, or proceed. -// If it receives from ctx.Done, it returns 0, the StreamError for ctx.Err. -// If it receives from done, it returns 0, io.EOF if ctx is not done; otherwise -// it return the StreamError for ctx.Err. -// If it receives from goAway, it returns 0, ErrStreamDrain. -// If it receives from closing, it returns 0, ErrConnClosing. -// If it receives from proceed, it returns the received integer, nil. -func wait(ctx context.Context, done, goAway, closing <-chan struct{}, proceed <-chan int) (int, error) { - select { - case <-ctx.Done(): - return 0, ContextErr(ctx.Err()) - case <-done: - // User cancellation has precedence. - select { - case <-ctx.Done(): - return 0, ContextErr(ctx.Err()) - default: - } - return 0, io.EOF - case <-goAway: - return 0, ErrStreamDrain - case <-closing: - return 0, ErrConnClosing - case i := <-proceed: - return i, nil - } -} |