vendor update

vendor/google.golang.org/grpc/rpc_util.go

@@ -0,0 +1,572 @@
+/*
+ *
+ * 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 (
+	"bytes"
+	"compress/gzip"
+	stdctx "context"
+	"encoding/binary"
+	"io"
+	"io/ioutil"
+	"math"
+	"os"
+	"sync"
+	"time"
+
+	"golang.org/x/net/context"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
+	"google.golang.org/grpc/transport"
+)
+
+// Compressor defines the interface gRPC uses to compress a message.
+type Compressor interface {
+	// Do compresses p into w.
+	Do(w io.Writer, p []byte) error
+	// Type returns the compression algorithm the Compressor uses.
+	Type() string
+}
+
+type gzipCompressor struct {
+	pool sync.Pool
+}
+
+// NewGZIPCompressor creates a Compressor based on GZIP.
+func NewGZIPCompressor() Compressor {
+	return &gzipCompressor{
+		pool: sync.Pool{
+			New: func() interface{} {
+				return gzip.NewWriter(ioutil.Discard)
+			},
+		},
+	}
+}
+
+func (c *gzipCompressor) Do(w io.Writer, p []byte) error {
+	z := c.pool.Get().(*gzip.Writer)
+	defer c.pool.Put(z)
+	z.Reset(w)
+	if _, err := z.Write(p); err != nil {
+		return err
+	}
+	return z.Close()
+}
+
+func (c *gzipCompressor) Type() string {
+	return "gzip"
+}
+
+// Decompressor defines the interface gRPC uses to decompress a message.
+type Decompressor interface {
+	// Do reads the data from r and uncompress them.
+	Do(r io.Reader) ([]byte, error)
+	// Type returns the compression algorithm the Decompressor uses.
+	Type() string
+}
+
+type gzipDecompressor struct {
+	pool sync.Pool
+}
+
+// NewGZIPDecompressor creates a Decompressor based on GZIP.
+func NewGZIPDecompressor() Decompressor {
+	return &gzipDecompressor{}
+}
+
+func (d *gzipDecompressor) Do(r io.Reader) ([]byte, error) {
+	var z *gzip.Reader
+	switch maybeZ := d.pool.Get().(type) {
+	case nil:
+		newZ, err := gzip.NewReader(r)
+		if err != nil {
+			return nil, err
+		}
+		z = newZ
+	case *gzip.Reader:
+		z = maybeZ
+		if err := z.Reset(r); err != nil {
+			d.pool.Put(z)
+			return nil, err
+		}
+	}
+
+	defer func() {
+		z.Close()
+		d.pool.Put(z)
+	}()
+	return ioutil.ReadAll(z)
+}
+
+func (d *gzipDecompressor) Type() string {
+	return "gzip"
+}
+
+// callInfo contains all related configuration and information about an RPC.
+type callInfo struct {
+	failFast              bool
+	headerMD              metadata.MD
+	trailerMD             metadata.MD
+	peer                  *peer.Peer
+	traceInfo             traceInfo // in trace.go
+	maxReceiveMessageSize *int
+	maxSendMessageSize    *int
+	creds                 credentials.PerRPCCredentials
+}
+
+func defaultCallInfo() *callInfo {
+	return &callInfo{failFast: true}
+}
+
+// CallOption configures a Call before it starts or extracts information from
+// a Call after it completes.
+type CallOption interface {
+	// before is called before the call is sent to any server.  If before
+	// returns a non-nil error, the RPC fails with that error.
+	before(*callInfo) error
+
+	// after is called after the call has completed.  after cannot return an
+	// error, so any failures should be reported via output parameters.
+	after(*callInfo)
+}
+
+// EmptyCallOption does not alter the Call configuration.
+// It can be embedded in another structure to carry satellite data for use
+// by interceptors.
+type EmptyCallOption struct{}
+
+func (EmptyCallOption) before(*callInfo) error { return nil }
+func (EmptyCallOption) after(*callInfo)        {}
+
+type beforeCall func(c *callInfo) error
+
+func (o beforeCall) before(c *callInfo) error { return o(c) }
+func (o beforeCall) after(c *callInfo)        {}
+
+type afterCall func(c *callInfo)
+
+func (o afterCall) before(c *callInfo) error { return nil }
+func (o afterCall) after(c *callInfo)        { o(c) }
+
+// Header returns a CallOptions that retrieves the header metadata
+// for a unary RPC.
+func Header(md *metadata.MD) CallOption {
+	return afterCall(func(c *callInfo) {
+		*md = c.headerMD
+	})
+}
+
+// Trailer returns a CallOptions that retrieves the trailer metadata
+// for a unary RPC.
+func Trailer(md *metadata.MD) CallOption {
+	return afterCall(func(c *callInfo) {
+		*md = c.trailerMD
+	})
+}
+
+// Peer returns a CallOption that retrieves peer information for a
+// unary RPC.
+func Peer(peer *peer.Peer) CallOption {
+	return afterCall(func(c *callInfo) {
+		if c.peer != nil {
+			*peer = *c.peer
+		}
+	})
+}
+
+// FailFast configures the action to take when an RPC is attempted on broken
+// connections or unreachable servers. If failfast is true, the RPC will fail
+// immediately. Otherwise, the RPC client will block the call until a
+// connection is available (or the call is canceled or times out) and will retry
+// the call if it fails due to a transient error. Please refer to
+// https://github.com/grpc/grpc/blob/master/doc/wait-for-ready.md.
+// Note: failFast is default to true.
+func FailFast(failFast bool) CallOption {
+	return beforeCall(func(c *callInfo) error {
+		c.failFast = failFast
+		return nil
+	})
+}
+
+// MaxCallRecvMsgSize returns a CallOption which sets the maximum message size the client can receive.
+func MaxCallRecvMsgSize(s int) CallOption {
+	return beforeCall(func(o *callInfo) error {
+		o.maxReceiveMessageSize = &s
+		return nil
+	})
+}
+
+// MaxCallSendMsgSize returns a CallOption which sets the maximum message size the client can send.
+func MaxCallSendMsgSize(s int) CallOption {
+	return beforeCall(func(o *callInfo) error {
+		o.maxSendMessageSize = &s
+		return nil
+	})
+}
+
+// PerRPCCredentials returns a CallOption that sets credentials.PerRPCCredentials
+// for a call.
+func PerRPCCredentials(creds credentials.PerRPCCredentials) CallOption {
+	return beforeCall(func(c *callInfo) error {
+		c.creds = creds
+		return nil
+	})
+}
+
+// The format of the payload: compressed or not?
+type payloadFormat uint8
+
+const (
+	compressionNone payloadFormat = iota // no compression
+	compressionMade
+)
+
+// parser reads complete gRPC messages from the underlying reader.
+type parser struct {
+	// r is the underlying reader.
+	// See the comment on recvMsg for the permissible
+	// error types.
+	r io.Reader
+
+	// The header of a gRPC message. Find more detail
+	// at https://grpc.io/docs/guides/wire.html.
+	header [5]byte
+}
+
+// recvMsg reads a complete gRPC message from the stream.
+//
+// It returns the message and its payload (compression/encoding)
+// format. The caller owns the returned msg memory.
+//
+// If there is an error, possible values are:
+//   * io.EOF, when no messages remain
+//   * io.ErrUnexpectedEOF
+//   * of type transport.ConnectionError
+//   * of type transport.StreamError
+// No other error values or types must be returned, which also means
+// that the underlying io.Reader must not return an incompatible
+// error.
+func (p *parser) recvMsg(maxReceiveMessageSize int) (pf payloadFormat, msg []byte, err error) {
+	if _, err := p.r.Read(p.header[:]); err != nil {
+		return 0, nil, err
+	}
+
+	pf = payloadFormat(p.header[0])
+	length := binary.BigEndian.Uint32(p.header[1:])
+
+	if length == 0 {
+		return pf, nil, nil
+	}
+	if length > uint32(maxReceiveMessageSize) {
+		return 0, nil, Errorf(codes.ResourceExhausted, "grpc: received message larger than max (%d vs. %d)", length, maxReceiveMessageSize)
+	}
+	// TODO(bradfitz,zhaoq): garbage. reuse buffer after proto decoding instead
+	// of making it for each message:
+	msg = make([]byte, int(length))
+	if _, err := p.r.Read(msg); err != nil {
+		if err == io.EOF {
+			err = io.ErrUnexpectedEOF
+		}
+		return 0, nil, err
+	}
+	return pf, msg, nil
+}
+
+// encode serializes msg and returns a buffer of message header and a buffer of msg.
+// If msg is nil, it generates the message header and an empty msg buffer.
+func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer, outPayload *stats.OutPayload) ([]byte, []byte, error) {
+	var b []byte
+	const (
+		payloadLen = 1
+		sizeLen    = 4
+	)
+
+	if msg != nil {
+		var err error
+		b, err = c.Marshal(msg)
+		if err != nil {
+			return nil, nil, Errorf(codes.Internal, "grpc: error while marshaling: %v", err.Error())
+		}
+		if outPayload != nil {
+			outPayload.Payload = msg
+			// TODO truncate large payload.
+			outPayload.Data = b
+			outPayload.Length = len(b)
+		}
+		if cp != nil {
+			if err := cp.Do(cbuf, b); err != nil {
+				return nil, nil, Errorf(codes.Internal, "grpc: error while compressing: %v", err.Error())
+			}
+			b = cbuf.Bytes()
+		}
+	}
+
+	if uint(len(b)) > math.MaxUint32 {
+		return nil, nil, Errorf(codes.ResourceExhausted, "grpc: message too large (%d bytes)", len(b))
+	}
+
+	bufHeader := make([]byte, payloadLen+sizeLen)
+	if cp == nil {
+		bufHeader[0] = byte(compressionNone)
+	} else {
+		bufHeader[0] = byte(compressionMade)
+	}
+	// Write length of b into buf
+	binary.BigEndian.PutUint32(bufHeader[payloadLen:], uint32(len(b)))
+	if outPayload != nil {
+		outPayload.WireLength = payloadLen + sizeLen + len(b)
+	}
+	return bufHeader, b, nil
+}
+
+func checkRecvPayload(pf payloadFormat, recvCompress string, dc Decompressor) error {
+	switch pf {
+	case compressionNone:
+	case compressionMade:
+		if dc == nil || recvCompress != dc.Type() {
+			return Errorf(codes.Unimplemented, "grpc: Decompressor is not installed for grpc-encoding %q", recvCompress)
+		}
+	default:
+		return Errorf(codes.Internal, "grpc: received unexpected payload format %d", pf)
+	}
+	return nil
+}
+
+func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{}, maxReceiveMessageSize int, inPayload *stats.InPayload) error {
+	pf, d, err := p.recvMsg(maxReceiveMessageSize)
+	if err != nil {
+		return err
+	}
+	if inPayload != nil {
+		inPayload.WireLength = len(d)
+	}
+	if err := checkRecvPayload(pf, s.RecvCompress(), dc); err != nil {
+		return err
+	}
+	if pf == compressionMade {
+		d, err = dc.Do(bytes.NewReader(d))
+		if err != nil {
+			return Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err)
+		}
+	}
+	if len(d) > maxReceiveMessageSize {
+		// TODO: Revisit the error code. Currently keep it consistent with java
+		// implementation.
+		return Errorf(codes.ResourceExhausted, "grpc: received message larger than max (%d vs. %d)", len(d), maxReceiveMessageSize)
+	}
+	if err := c.Unmarshal(d, m); err != nil {
+		return Errorf(codes.Internal, "grpc: failed to unmarshal the received message %v", err)
+	}
+	if inPayload != nil {
+		inPayload.RecvTime = time.Now()
+		inPayload.Payload = m
+		// TODO truncate large payload.
+		inPayload.Data = d
+		inPayload.Length = len(d)
+	}
+	return nil
+}
+
+type rpcInfo struct {
+	failfast      bool
+	bytesSent     bool
+	bytesReceived bool
+}
+
+type rpcInfoContextKey struct{}
+
+func newContextWithRPCInfo(ctx context.Context, failfast bool) context.Context {
+	return context.WithValue(ctx, rpcInfoContextKey{}, &rpcInfo{failfast: failfast})
+}
+
+func rpcInfoFromContext(ctx context.Context) (s *rpcInfo, ok bool) {
+	s, ok = ctx.Value(rpcInfoContextKey{}).(*rpcInfo)
+	return
+}
+
+func updateRPCInfoInContext(ctx context.Context, s rpcInfo) {
+	if ss, ok := rpcInfoFromContext(ctx); ok {
+		ss.bytesReceived = s.bytesReceived
+		ss.bytesSent = s.bytesSent
+	}
+	return
+}
+
+// toRPCErr converts an error into an error from the status package.
+func toRPCErr(err error) error {
+	if _, ok := status.FromError(err); ok {
+		return err
+	}
+	switch e := err.(type) {
+	case transport.StreamError:
+		return status.Error(e.Code, e.Desc)
+	case transport.ConnectionError:
+		return status.Error(codes.Unavailable, e.Desc)
+	default:
+		switch err {
+		case context.DeadlineExceeded, stdctx.DeadlineExceeded:
+			return status.Error(codes.DeadlineExceeded, err.Error())
+		case context.Canceled, stdctx.Canceled:
+			return status.Error(codes.Canceled, err.Error())
+		case ErrClientConnClosing:
+			return status.Error(codes.FailedPrecondition, err.Error())
+		}
+	}
+	return status.Error(codes.Unknown, err.Error())
+}
+
+// convertCode converts a standard Go error into its canonical code. Note that
+// this is only used to translate the error returned by the server applications.
+func convertCode(err error) codes.Code {
+	switch err {
+	case nil:
+		return codes.OK
+	case io.EOF:
+		return codes.OutOfRange
+	case io.ErrClosedPipe, io.ErrNoProgress, io.ErrShortBuffer, io.ErrShortWrite, io.ErrUnexpectedEOF:
+		return codes.FailedPrecondition
+	case os.ErrInvalid:
+		return codes.InvalidArgument
+	case context.Canceled, stdctx.Canceled:
+		return codes.Canceled
+	case context.DeadlineExceeded, stdctx.DeadlineExceeded:
+		return codes.DeadlineExceeded
+	}
+	switch {
+	case os.IsExist(err):
+		return codes.AlreadyExists
+	case os.IsNotExist(err):
+		return codes.NotFound
+	case os.IsPermission(err):
+		return codes.PermissionDenied
+	}
+	return codes.Unknown
+}
+
+// Code returns the error code for err if it was produced by the rpc system.
+// Otherwise, it returns codes.Unknown.
+//
+// Deprecated; use status.FromError and Code method instead.
+func Code(err error) codes.Code {
+	if s, ok := status.FromError(err); ok {
+		return s.Code()
+	}
+	return codes.Unknown
+}
+
+// ErrorDesc returns the error description of err if it was produced by the rpc system.
+// Otherwise, it returns err.Error() or empty string when err is nil.
+//
+// Deprecated; use status.FromError and Message method instead.
+func ErrorDesc(err error) string {
+	if s, ok := status.FromError(err); ok {
+		return s.Message()
+	}
+	return err.Error()
+}
+
+// Errorf returns an error containing an error code and a description;
+// Errorf returns nil if c is OK.
+//
+// Deprecated; use status.Errorf instead.
+func Errorf(c codes.Code, format string, a ...interface{}) error {
+	return status.Errorf(c, format, a...)
+}
+
+// MethodConfig defines the configuration recommended by the service providers for a
+// particular method.
+// This is EXPERIMENTAL and subject to change.
+type MethodConfig struct {
+	// WaitForReady indicates whether RPCs sent to this method should wait until
+	// the connection is ready by default (!failfast). The value specified via the
+	// gRPC client API will override the value set here.
+	WaitForReady *bool
+	// Timeout is the default timeout for RPCs sent to this method. The actual
+	// deadline used will be the minimum of the value specified here and the value
+	// set by the application via the gRPC client API.  If either one is not set,
+	// then the other will be used.  If neither is set, then the RPC has no deadline.
+	Timeout *time.Duration
+	// MaxReqSize is the maximum allowed payload size for an individual request in a
+	// stream (client->server) in bytes. The size which is measured is the serialized
+	// payload after per-message compression (but before stream compression) in bytes.
+	// The actual value used is the minimum of the value specified here and the value set
+	// by the application via the gRPC client API. If either one is not set, then the other
+	// will be used.  If neither is set, then the built-in default is used.
+	MaxReqSize *int
+	// MaxRespSize is the maximum allowed payload size for an individual response in a
+	// stream (server->client) in bytes.
+	MaxRespSize *int
+}
+
+// ServiceConfig is provided by the service provider and contains parameters for how
+// clients that connect to the service should behave.
+// This is EXPERIMENTAL and subject to change.
+type ServiceConfig struct {
+	// LB is the load balancer the service providers recommends. The balancer specified
+	// via grpc.WithBalancer will override this.
+	LB Balancer
+	// Methods contains a map for the methods in this service.
+	// If there is an exact match for a method (i.e. /service/method) in the map, use the corresponding MethodConfig.
+	// If there's no exact match, look for the default config for the service (/service/) and use the corresponding MethodConfig if it exists.
+	// Otherwise, the method has no MethodConfig to use.
+	Methods map[string]MethodConfig
+}
+
+func min(a, b *int) *int {
+	if *a < *b {
+		return a
+	}
+	return b
+}
+
+func getMaxSize(mcMax, doptMax *int, defaultVal int) *int {
+	if mcMax == nil && doptMax == nil {
+		return &defaultVal
+	}
+	if mcMax != nil && doptMax != nil {
+		return min(mcMax, doptMax)
+	}
+	if mcMax != nil {
+		return mcMax
+	}
+	return doptMax
+}
+
+// SupportPackageIsVersion3 is referenced from generated protocol buffer files.
+// The latest support package version is 4.
+// SupportPackageIsVersion3 is kept for compatibility. It will be removed in the
+// next support package version update.
+const SupportPackageIsVersion3 = true
+
+// SupportPackageIsVersion4 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the grpc package.
+//
+// This constant may be renamed in the future if a change in the generated code
+// requires a synchronised update of grpc-go and protoc-gen-go. This constant
+// should not be referenced from any other code.
+const SupportPackageIsVersion4 = true
+
+// Version is the current grpc version.
+const Version = "1.7.5"
+
+const grpcUA = "grpc-go/" + Version