ceph-csi/vendor/google.golang.org/grpc/rpc_util.go
Serguei Bezverkhi 7b24313bd6 vendor files
2018-01-10 13:42:26 -05:00

506 lines
15 KiB
Go

/*
*
* 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"
"io"
"io/ioutil"
"math"
"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/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 {
compressorType string
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. 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 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
})
}
// 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 beforeCall(func(c *callInfo) error {
c.compressorType = name
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 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 of message header and a buffer of msg.
// If msg is nil, it generates the message header and an empty msg buffer.
// TODO(ddyihai): eliminate extra Compressor parameter.
func encode(c Codec, msg interface{}, cp Compressor, outPayload *stats.OutPayload, compressor encoding.Compressor) ([]byte, []byte, error) {
var (
b []byte
cbuf *bytes.Buffer
)
const (
payloadLen = 1
sizeLen = 4
)
if msg != nil {
var err error
b, err = c.Marshal(msg)
if err != nil {
return nil, nil, status.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 compressor != nil || cp != nil {
cbuf = new(bytes.Buffer)
// Has compressor, check Compressor is set by UseCompressor first.
if compressor != nil {
z, _ := compressor.Compress(cbuf)
if _, err := z.Write(b); err != nil {
return nil, nil, status.Errorf(codes.Internal, "grpc: error while compressing: %v", err.Error())
}
z.Close()
} else {
// If Compressor is not set by UseCompressor, use default Compressor
if err := cp.Do(cbuf, b); err != nil {
return nil, nil, status.Errorf(codes.Internal, "grpc: error while compressing: %v", err.Error())
}
}
b = cbuf.Bytes()
}
}
if uint(len(b)) > math.MaxUint32 {
return nil, nil, status.Errorf(codes.ResourceExhausted, "grpc: message too large (%d bytes)", len(b))
}
bufHeader := make([]byte, payloadLen+sizeLen)
if compressor != nil || cp != nil {
bufHeader[0] = byte(compressionMade)
} else {
bufHeader[0] = byte(compressionNone)
}
// 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, 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 Codec, 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...)
}
// 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
)
// Version is the current grpc version.
const Version = "1.9.0"
const grpcUA = "grpc-go/" + Version