diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/rpc_util.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/rpc_util.go | 780 |
1 files changed, 0 insertions, 780 deletions
diff --git a/vendor/google.golang.org/grpc/rpc_util.go b/vendor/google.golang.org/grpc/rpc_util.go deleted file mode 100644 index 207f0ee..0000000 --- a/vendor/google.golang.org/grpc/rpc_util.go +++ /dev/null @@ -1,780 +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 ( - "bytes" - "compress/gzip" - "encoding/binary" - "fmt" - "io" - "io/ioutil" - "math" - "net/url" - "strings" - "sync" - "time" - - "golang.org/x/net/context" - "google.golang.org/grpc/codes" - "google.golang.org/grpc/credentials" - "google.golang.org/grpc/encoding" - "google.golang.org/grpc/encoding/proto" - "google.golang.org/grpc/internal/transport" - "google.golang.org/grpc/metadata" - "google.golang.org/grpc/peer" - "google.golang.org/grpc/stats" - "google.golang.org/grpc/status" -) - -// Compressor defines the interface gRPC uses to compress a message. -// -// Deprecated: use package encoding. -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. -// -// Deprecated: use package encoding/gzip. -func NewGZIPCompressor() Compressor { - c, _ := NewGZIPCompressorWithLevel(gzip.DefaultCompression) - return c -} - -// NewGZIPCompressorWithLevel is like NewGZIPCompressor but specifies the gzip compression level instead -// of assuming DefaultCompression. -// -// The error returned will be nil if the level is valid. -// -// Deprecated: use package encoding/gzip. -func NewGZIPCompressorWithLevel(level int) (Compressor, error) { - if level < gzip.DefaultCompression || level > gzip.BestCompression { - return nil, fmt.Errorf("grpc: invalid compression level: %d", level) - } - return &gzipCompressor{ - pool: sync.Pool{ - New: func() interface{} { - w, err := gzip.NewWriterLevel(ioutil.Discard, level) - if err != nil { - panic(err) - } - return w - }, - }, - }, nil -} - -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. -// -// Deprecated: use package encoding. -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. -// -// Deprecated: use package encoding/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 { - compressorType string - failFast bool - stream *clientStream - traceInfo traceInfo // in trace.go - maxReceiveMessageSize *int - maxSendMessageSize *int - creds credentials.PerRPCCredentials - contentSubtype string - codec baseCodec - disableRetry bool - maxRetryRPCBufferSize int -} - -func defaultCallInfo() *callInfo { - return &callInfo{ - failFast: true, - maxRetryRPCBufferSize: 256 * 1024, // 256KB - } -} - -// 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) {} - -// Header returns a CallOptions that retrieves the header metadata -// for a unary RPC. -func Header(md *metadata.MD) CallOption { - return HeaderCallOption{HeaderAddr: md} -} - -// HeaderCallOption is a CallOption for collecting response header metadata. -// The metadata field will be populated *after* the RPC completes. -// This is an EXPERIMENTAL API. -type HeaderCallOption struct { - HeaderAddr *metadata.MD -} - -func (o HeaderCallOption) before(c *callInfo) error { return nil } -func (o HeaderCallOption) after(c *callInfo) { - if c.stream != nil { - *o.HeaderAddr, _ = c.stream.Header() - } -} - -// Trailer returns a CallOptions that retrieves the trailer metadata -// for a unary RPC. -func Trailer(md *metadata.MD) CallOption { - return TrailerCallOption{TrailerAddr: md} -} - -// TrailerCallOption is a CallOption for collecting response trailer metadata. -// The metadata field will be populated *after* the RPC completes. -// This is an EXPERIMENTAL API. -type TrailerCallOption struct { - TrailerAddr *metadata.MD -} - -func (o TrailerCallOption) before(c *callInfo) error { return nil } -func (o TrailerCallOption) after(c *callInfo) { - if c.stream != nil { - *o.TrailerAddr = c.stream.Trailer() - } -} - -// Peer returns a CallOption that retrieves peer information for a unary RPC. -// The peer field will be populated *after* the RPC completes. -func Peer(p *peer.Peer) CallOption { - return PeerCallOption{PeerAddr: p} -} - -// PeerCallOption is a CallOption for collecting the identity of the remote -// peer. The peer field will be populated *after* the RPC completes. -// This is an EXPERIMENTAL API. -type PeerCallOption struct { - PeerAddr *peer.Peer -} - -func (o PeerCallOption) before(c *callInfo) error { return nil } -func (o PeerCallOption) after(c *callInfo) { - if c.stream != nil { - if x, ok := peer.FromContext(c.stream.Context()); ok { - *o.PeerAddr = *x - } - } -} - -// 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. gRPC will not retry if -// data was written to the wire unless the server indicates it did not process -// the data. Please refer to -// https://github.com/grpc/grpc/blob/master/doc/wait-for-ready.md. -// -// By default, RPCs are "Fail Fast". -func FailFast(failFast bool) CallOption { - return FailFastCallOption{FailFast: failFast} -} - -// FailFastCallOption is a CallOption for indicating whether an RPC should fail -// fast or not. -// This is an EXPERIMENTAL API. -type FailFastCallOption struct { - FailFast bool -} - -func (o FailFastCallOption) before(c *callInfo) error { - c.failFast = o.FailFast - return nil -} -func (o FailFastCallOption) after(c *callInfo) {} - -// MaxCallRecvMsgSize returns a CallOption which sets the maximum message size the client can receive. -func MaxCallRecvMsgSize(s int) CallOption { - return MaxRecvMsgSizeCallOption{MaxRecvMsgSize: s} -} - -// MaxRecvMsgSizeCallOption is a CallOption that indicates the maximum message -// size the client can receive. -// This is an EXPERIMENTAL API. -type MaxRecvMsgSizeCallOption struct { - MaxRecvMsgSize int -} - -func (o MaxRecvMsgSizeCallOption) before(c *callInfo) error { - c.maxReceiveMessageSize = &o.MaxRecvMsgSize - return nil -} -func (o MaxRecvMsgSizeCallOption) after(c *callInfo) {} - -// MaxCallSendMsgSize returns a CallOption which sets the maximum message size the client can send. -func MaxCallSendMsgSize(s int) CallOption { - return MaxSendMsgSizeCallOption{MaxSendMsgSize: s} -} - -// MaxSendMsgSizeCallOption is a CallOption that indicates the maximum message -// size the client can send. -// This is an EXPERIMENTAL API. -type MaxSendMsgSizeCallOption struct { - MaxSendMsgSize int -} - -func (o MaxSendMsgSizeCallOption) before(c *callInfo) error { - c.maxSendMessageSize = &o.MaxSendMsgSize - return nil -} -func (o MaxSendMsgSizeCallOption) after(c *callInfo) {} - -// PerRPCCredentials returns a CallOption that sets credentials.PerRPCCredentials -// for a call. -func PerRPCCredentials(creds credentials.PerRPCCredentials) CallOption { - return PerRPCCredsCallOption{Creds: creds} -} - -// PerRPCCredsCallOption is a CallOption that indicates the per-RPC -// credentials to use for the call. -// This is an EXPERIMENTAL API. -type PerRPCCredsCallOption struct { - Creds credentials.PerRPCCredentials -} - -func (o PerRPCCredsCallOption) before(c *callInfo) error { - c.creds = o.Creds - return nil -} -func (o PerRPCCredsCallOption) after(c *callInfo) {} - -// UseCompressor returns a CallOption which sets the compressor used when -// sending the request. If WithCompressor is also set, UseCompressor has -// higher priority. -// -// This API is EXPERIMENTAL. -func UseCompressor(name string) CallOption { - return CompressorCallOption{CompressorType: name} -} - -// CompressorCallOption is a CallOption that indicates the compressor to use. -// This is an EXPERIMENTAL API. -type CompressorCallOption struct { - CompressorType string -} - -func (o CompressorCallOption) before(c *callInfo) error { - c.compressorType = o.CompressorType - return nil -} -func (o CompressorCallOption) after(c *callInfo) {} - -// CallContentSubtype returns a CallOption that will set the content-subtype -// for a call. For example, if content-subtype is "json", the Content-Type over -// the wire will be "application/grpc+json". The content-subtype is converted -// to lowercase before being included in Content-Type. See Content-Type on -// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for -// more details. -// -// If CallCustomCodec is not also used, the content-subtype will be used to -// look up the Codec to use in the registry controlled by RegisterCodec. See -// the documentation on RegisterCodec for details on registration. The lookup -// of content-subtype is case-insensitive. If no such Codec is found, the call -// will result in an error with code codes.Internal. -// -// If CallCustomCodec is also used, that Codec will be used for all request and -// response messages, with the content-subtype set to the given contentSubtype -// here for requests. -func CallContentSubtype(contentSubtype string) CallOption { - return ContentSubtypeCallOption{ContentSubtype: strings.ToLower(contentSubtype)} -} - -// ContentSubtypeCallOption is a CallOption that indicates the content-subtype -// used for marshaling messages. -// This is an EXPERIMENTAL API. -type ContentSubtypeCallOption struct { - ContentSubtype string -} - -func (o ContentSubtypeCallOption) before(c *callInfo) error { - c.contentSubtype = o.ContentSubtype - return nil -} -func (o ContentSubtypeCallOption) after(c *callInfo) {} - -// CallCustomCodec returns a CallOption that will set the given Codec to be -// used for all request and response messages for a call. The result of calling -// String() will be used as the content-subtype in a case-insensitive manner. -// -// See Content-Type on -// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for -// more details. Also see the documentation on RegisterCodec and -// CallContentSubtype for more details on the interaction between Codec and -// content-subtype. -// -// This function is provided for advanced users; prefer to use only -// CallContentSubtype to select a registered codec instead. -func CallCustomCodec(codec Codec) CallOption { - return CustomCodecCallOption{Codec: codec} -} - -// CustomCodecCallOption is a CallOption that indicates the codec used for -// marshaling messages. -// This is an EXPERIMENTAL API. -type CustomCodecCallOption struct { - Codec Codec -} - -func (o CustomCodecCallOption) before(c *callInfo) error { - c.codec = o.Codec - return nil -} -func (o CustomCodecCallOption) after(c *callInfo) {} - -// MaxRetryRPCBufferSize returns a CallOption that limits the amount of memory -// used for buffering this RPC's requests for retry purposes. -// -// This API is EXPERIMENTAL. -func MaxRetryRPCBufferSize(bytes int) CallOption { - return MaxRetryRPCBufferSizeCallOption{bytes} -} - -// MaxRetryRPCBufferSizeCallOption is a CallOption indicating the amount of -// memory to be used for caching this RPC for retry purposes. -// This is an EXPERIMENTAL API. -type MaxRetryRPCBufferSizeCallOption struct { - MaxRetryRPCBufferSize int -} - -func (o MaxRetryRPCBufferSizeCallOption) before(c *callInfo) error { - c.maxRetryRPCBufferSize = o.MaxRetryRPCBufferSize - return nil -} -func (o MaxRetryRPCBufferSizeCallOption) after(c *callInfo) {} - -// The format of the payload: compressed or not? -type payloadFormat uint8 - -const ( - compressionNone payloadFormat = 0 // no compression - compressionMade payloadFormat = 1 // compressed -) - -// 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://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md - 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 -// * an error from the status package -// 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 int64(length) > int64(maxInt) { - return 0, nil, status.Errorf(codes.ResourceExhausted, "grpc: received message larger than max length allowed on current machine (%d vs. %d)", length, maxInt) - } - if int(length) > maxReceiveMessageSize { - return 0, nil, status.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 containing the message, or an -// error if it is too large to be transmitted by grpc. If msg is nil, it -// generates an empty message. -func encode(c baseCodec, msg interface{}) ([]byte, error) { - if msg == nil { // NOTE: typed nils will not be caught by this check - return nil, nil - } - b, err := c.Marshal(msg) - if err != nil { - return nil, status.Errorf(codes.Internal, "grpc: error while marshaling: %v", err.Error()) - } - if uint(len(b)) > math.MaxUint32 { - return nil, status.Errorf(codes.ResourceExhausted, "grpc: message too large (%d bytes)", len(b)) - } - return b, nil -} - -// compress returns the input bytes compressed by compressor or cp. If both -// compressors are nil, returns nil. -// -// TODO(dfawley): eliminate cp parameter by wrapping Compressor in an encoding.Compressor. -func compress(in []byte, cp Compressor, compressor encoding.Compressor) ([]byte, error) { - if compressor == nil && cp == nil { - return nil, nil - } - wrapErr := func(err error) error { - return status.Errorf(codes.Internal, "grpc: error while compressing: %v", err.Error()) - } - cbuf := &bytes.Buffer{} - if compressor != nil { - z, _ := compressor.Compress(cbuf) - if _, err := z.Write(in); err != nil { - return nil, wrapErr(err) - } - if err := z.Close(); err != nil { - return nil, wrapErr(err) - } - } else { - if err := cp.Do(cbuf, in); err != nil { - return nil, wrapErr(err) - } - } - return cbuf.Bytes(), nil -} - -const ( - payloadLen = 1 - sizeLen = 4 - headerLen = payloadLen + sizeLen -) - -// msgHeader returns a 5-byte header for the message being transmitted and the -// payload, which is compData if non-nil or data otherwise. -func msgHeader(data, compData []byte) (hdr []byte, payload []byte) { - hdr = make([]byte, headerLen) - if compData != nil { - hdr[0] = byte(compressionMade) - data = compData - } else { - hdr[0] = byte(compressionNone) - } - - // Write length of payload into buf - binary.BigEndian.PutUint32(hdr[payloadLen:], uint32(len(data))) - return hdr, data -} - -func outPayload(client bool, msg interface{}, data, payload []byte, t time.Time) *stats.OutPayload { - return &stats.OutPayload{ - Client: client, - Payload: msg, - Data: data, - Length: len(data), - WireLength: len(payload) + headerLen, - SentTime: t, - } -} - -func checkRecvPayload(pf payloadFormat, recvCompress string, haveCompressor bool) *status.Status { - switch pf { - case compressionNone: - case compressionMade: - if recvCompress == "" || recvCompress == encoding.Identity { - return status.New(codes.Internal, "grpc: compressed flag set with identity or empty encoding") - } - if !haveCompressor { - return status.Newf(codes.Unimplemented, "grpc: Decompressor is not installed for grpc-encoding %q", recvCompress) - } - default: - return status.Newf(codes.Internal, "grpc: received unexpected payload format %d", pf) - } - return nil -} - -// For the two compressor parameters, both should not be set, but if they are, -// dc takes precedence over compressor. -// TODO(dfawley): wrap the old compressor/decompressor using the new API? -func recv(p *parser, c baseCodec, s *transport.Stream, dc Decompressor, m interface{}, maxReceiveMessageSize int, inPayload *stats.InPayload, compressor encoding.Compressor) error { - pf, d, err := p.recvMsg(maxReceiveMessageSize) - if err != nil { - return err - } - if inPayload != nil { - inPayload.WireLength = len(d) - } - - if st := checkRecvPayload(pf, s.RecvCompress(), compressor != nil || dc != nil); st != nil { - return st.Err() - } - - if pf == compressionMade { - // To match legacy behavior, if the decompressor is set by WithDecompressor or RPCDecompressor, - // use this decompressor as the default. - if dc != nil { - d, err = dc.Do(bytes.NewReader(d)) - if err != nil { - return status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err) - } - } else { - dcReader, err := compressor.Decompress(bytes.NewReader(d)) - if err != nil { - return status.Errorf(codes.Internal, "grpc: failed to decompress the received message %v", err) - } - d, err = ioutil.ReadAll(dcReader) - if err != nil { - return status.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 status.Errorf(codes.ResourceExhausted, "grpc: received message larger than max (%d vs. %d)", len(d), maxReceiveMessageSize) - } - if err := c.Unmarshal(d, m); err != nil { - return status.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 -} - -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 -} - -// 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...) -} - -// setCallInfoCodec should only be called after CallOptions have been applied. -func setCallInfoCodec(c *callInfo) error { - if c.codec != nil { - // codec was already set by a CallOption; use it. - return nil - } - - if c.contentSubtype == "" { - // No codec specified in CallOptions; use proto by default. - c.codec = encoding.GetCodec(proto.Name) - return nil - } - - // c.contentSubtype is already lowercased in CallContentSubtype - c.codec = encoding.GetCodec(c.contentSubtype) - if c.codec == nil { - return status.Errorf(codes.Internal, "no codec registered for content-subtype %s", c.contentSubtype) - } - return nil -} - -// parseDialTarget returns the network and address to pass to dialer -func parseDialTarget(target string) (net string, addr string) { - net = "tcp" - - m1 := strings.Index(target, ":") - m2 := strings.Index(target, ":/") - - // handle unix:addr which will fail with url.Parse - if m1 >= 0 && m2 < 0 { - if n := target[0:m1]; n == "unix" { - net = n - addr = target[m1+1:] - return net, addr - } - } - if m2 >= 0 { - t, err := url.Parse(target) - if err != nil { - return net, target - } - scheme := t.Scheme - addr = t.Path - if scheme == "unix" { - net = scheme - if addr == "" { - addr = t.Host - } - return net, addr - } - } - - return net, target -} - -// channelzData is used to store channelz related data for ClientConn, addrConn and Server. -// These fields cannot be embedded in the original structs (e.g. ClientConn), 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 { - callsStarted int64 - callsFailed int64 - callsSucceeded int64 - // lastCallStartedTime stores the timestamp that last call starts. It is of int64 type instead of - // time.Time since it's more costly to atomically update time.Time variable than int64 variable. - lastCallStartedTime int64 -} - -// The SupportPackageIsVersion variables are referenced from generated protocol -// buffer files to ensure compatibility with the gRPC version used. The latest -// support package version is 5. -// -// Older versions are kept for compatibility. They may be removed if -// compatibility cannot be maintained. -// -// These constants should not be referenced from any other code. -const ( - SupportPackageIsVersion3 = true - SupportPackageIsVersion4 = true - SupportPackageIsVersion5 = true -) - -const grpcUA = "grpc-go/" + Version |