458 lines
13 KiB
Go
458 lines
13 KiB
Go
|
/*
|
||
|
|
*
|
||
|
|
* 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 grpc
|
||
|
|
|
||
|
|
import (
|
||
|
|
"bytes"
|
||
|
|
"compress/gzip"
|
||
|
|
"encoding/binary"
|
||
|
|
"fmt"
|
||
|
|
"io"
|
||
|
|
"io/ioutil"
|
||
|
|
"math"
|
||
|
|
"os"
|
||
|
|
|
||
|
|
"github.com/golang/protobuf/proto"
|
||
|
|
"golang.org/x/net/context"
|
||
|
|
"google.golang.org/grpc/codes"
|
||
|
|
"google.golang.org/grpc/metadata"
|
||
|
|
"google.golang.org/grpc/transport"
|
||
|
|
)
|
||
|
|
|
||
|
|
// Codec defines the interface gRPC uses to encode and decode messages.
|
||
|
|
type Codec interface {
|
||
|
|
// Marshal returns the wire format of v.
|
||
|
|
Marshal(v interface{}) ([]byte, error)
|
||
|
|
// Unmarshal parses the wire format into v.
|
||
|
|
Unmarshal(data []byte, v interface{}) error
|
||
|
|
// String returns the name of the Codec implementation. The returned
|
||
|
|
// string will be used as part of content type in transmission.
|
||
|
|
String() string
|
||
|
|
}
|
||
|
|
|
||
|
|
// protoCodec is a Codec implementation with protobuf. It is the default codec for gRPC.
|
||
|
|
type protoCodec struct{}
|
||
|
|
|
||
|
|
func (protoCodec) Marshal(v interface{}) ([]byte, error) {
|
||
|
|
return proto.Marshal(v.(proto.Message))
|
||
|
|
}
|
||
|
|
|
||
|
|
func (protoCodec) Unmarshal(data []byte, v interface{}) error {
|
||
|
|
return proto.Unmarshal(data, v.(proto.Message))
|
||
|
|
}
|
||
|
|
|
||
|
|
func (protoCodec) String() string {
|
||
|
|
return "proto"
|
||
|
|
}
|
||
|
|
|
||
|
|
// 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
|
||
|
|
}
|
||
|
|
|
||
|
|
// NewGZIPCompressor creates a Compressor based on GZIP.
|
||
|
|
func NewGZIPCompressor() Compressor {
|
||
|
|
return &gzipCompressor{}
|
||
|
|
}
|
||
|
|
|
||
|
|
type gzipCompressor struct {
|
||
|
|
}
|
||
|
|
|
||
|
|
func (c *gzipCompressor) Do(w io.Writer, p []byte) error {
|
||
|
|
z := gzip.NewWriter(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 {
|
||
|
|
}
|
||
|
|
|
||
|
|
// NewGZIPDecompressor creates a Decompressor based on GZIP.
|
||
|
|
func NewGZIPDecompressor() Decompressor {
|
||
|
|
return &gzipDecompressor{}
|
||
|
|
}
|
||
|
|
|
||
|
|
func (d *gzipDecompressor) Do(r io.Reader) ([]byte, error) {
|
||
|
|
z, err := gzip.NewReader(r)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
defer z.Close()
|
||
|
|
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
|
||
|
|
traceInfo traceInfo // in trace.go
|
||
|
|
}
|
||
|
|
|
||
|
|
var defaultCallInfo = 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)
|
||
|
|
}
|
||
|
|
|
||
|
|
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
|
||
|
|
})
|
||
|
|
}
|
||
|
|
|
||
|
|
// 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/fail_fast.md
|
||
|
|
func FailFast(failFast bool) CallOption {
|
||
|
|
return beforeCall(func(c *callInfo) error {
|
||
|
|
c.failFast = failFast
|
||
|
|
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 http://www.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(maxMsgSize int) (pf payloadFormat, msg []byte, err error) {
|
||
|
|
if _, err := io.ReadFull(p.r, 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(maxMsgSize) {
|
||
|
|
return 0, nil, Errorf(codes.Internal, "grpc: received message length %d exceeding the max size %d", length, maxMsgSize)
|
||
|
|
}
|
||
|
|
// TODO(bradfitz,zhaoq): garbage. reuse buffer after proto decoding instead
|
||
|
|
// of making it for each message:
|
||
|
|
msg = make([]byte, int(length))
|
||
|
|
if _, err := io.ReadFull(p.r, msg); err != nil {
|
||
|
|
if err == io.EOF {
|
||
|
|
err = io.ErrUnexpectedEOF
|
||
|
|
}
|
||
|
|
return 0, nil, err
|
||
|
|
}
|
||
|
|
return pf, msg, nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// encode serializes msg and prepends the message header. If msg is nil, it
|
||
|
|
// generates the message header of 0 message length.
|
||
|
|
func encode(c Codec, msg interface{}, cp Compressor, cbuf *bytes.Buffer) ([]byte, error) {
|
||
|
|
var b []byte
|
||
|
|
var length uint
|
||
|
|
if msg != nil {
|
||
|
|
var err error
|
||
|
|
// TODO(zhaoq): optimize to reduce memory alloc and copying.
|
||
|
|
b, err = c.Marshal(msg)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
if cp != nil {
|
||
|
|
if err := cp.Do(cbuf, b); err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
b = cbuf.Bytes()
|
||
|
|
}
|
||
|
|
length = uint(len(b))
|
||
|
|
}
|
||
|
|
if length > math.MaxUint32 {
|
||
|
|
return nil, Errorf(codes.InvalidArgument, "grpc: message too large (%d bytes)", length)
|
||
|
|
}
|
||
|
|
|
||
|
|
const (
|
||
|
|
payloadLen = 1
|
||
|
|
sizeLen = 4
|
||
|
|
)
|
||
|
|
|
||
|
|
var buf = make([]byte, payloadLen+sizeLen+len(b))
|
||
|
|
|
||
|
|
// Write payload format
|
||
|
|
if cp == nil {
|
||
|
|
buf[0] = byte(compressionNone)
|
||
|
|
} else {
|
||
|
|
buf[0] = byte(compressionMade)
|
||
|
|
}
|
||
|
|
// Write length of b into buf
|
||
|
|
binary.BigEndian.PutUint32(buf[1:], uint32(length))
|
||
|
|
// Copy encoded msg to buf
|
||
|
|
copy(buf[5:], b)
|
||
|
|
|
||
|
|
return buf, 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{}, maxMsgSize int) error {
|
||
|
|
pf, d, err := p.recvMsg(maxMsgSize)
|
||
|
|
if err != nil {
|
||
|
|
return err
|
||
|
|
}
|
||
|
|
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) > maxMsgSize {
|
||
|
|
// TODO: Revisit the error code. Currently keep it consistent with java
|
||
|
|
// implementation.
|
||
|
|
return Errorf(codes.Internal, "grpc: received a message of %d bytes exceeding %d limit", len(d), maxMsgSize)
|
||
|
|
}
|
||
|
|
if err := c.Unmarshal(d, m); err != nil {
|
||
|
|
return Errorf(codes.Internal, "grpc: failed to unmarshal the received message %v", err)
|
||
|
|
}
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// rpcError defines the status from an RPC.
|
||
|
|
type rpcError struct {
|
||
|
|
code codes.Code
|
||
|
|
desc string
|
||
|
|
}
|
||
|
|
|
||
|
|
func (e *rpcError) Error() string {
|
||
|
|
return fmt.Sprintf("rpc error: code = %d desc = %s", e.code, e.desc)
|
||
|
|
}
|
||
|
|
|
||
|
|
// Code returns the error code for err if it was produced by the rpc system.
|
||
|
|
// Otherwise, it returns codes.Unknown.
|
||
|
|
func Code(err error) codes.Code {
|
||
|
|
if err == nil {
|
||
|
|
return codes.OK
|
||
|
|
}
|
||
|
|
if e, ok := err.(*rpcError); ok {
|
||
|
|
return e.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.
|
||
|
|
func ErrorDesc(err error) string {
|
||
|
|
if err == nil {
|
||
|
|
return ""
|
||
|
|
}
|
||
|
|
if e, ok := err.(*rpcError); ok {
|
||
|
|
return e.desc
|
||
|
|
}
|
||
|
|
return err.Error()
|
||
|
|
}
|
||
|
|
|
||
|
|
// Errorf returns an error containing an error code and a description;
|
||
|
|
// Errorf returns nil if c is OK.
|
||
|
|
func Errorf(c codes.Code, format string, a ...interface{}) error {
|
||
|
|
if c == codes.OK {
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
return &rpcError{
|
||
|
|
code: c,
|
||
|
|
desc: fmt.Sprintf(format, a...),
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// toRPCErr converts an error into a rpcError.
|
||
|
|
func toRPCErr(err error) error {
|
||
|
|
switch e := err.(type) {
|
||
|
|
case *rpcError:
|
||
|
|
return err
|
||
|
|
case transport.StreamError:
|
||
|
|
return &rpcError{
|
||
|
|
code: e.Code,
|
||
|
|
desc: e.Desc,
|
||
|
|
}
|
||
|
|
case transport.ConnectionError:
|
||
|
|
return &rpcError{
|
||
|
|
code: codes.Internal,
|
||
|
|
desc: e.Desc,
|
||
|
|
}
|
||
|
|
default:
|
||
|
|
switch err {
|
||
|
|
case context.DeadlineExceeded:
|
||
|
|
return &rpcError{
|
||
|
|
code: codes.DeadlineExceeded,
|
||
|
|
desc: err.Error(),
|
||
|
|
}
|
||
|
|
case context.Canceled:
|
||
|
|
return &rpcError{
|
||
|
|
code: codes.Canceled,
|
||
|
|
desc: err.Error(),
|
||
|
|
}
|
||
|
|
case ErrClientConnClosing:
|
||
|
|
return &rpcError{
|
||
|
|
code: codes.FailedPrecondition,
|
||
|
|
desc: err.Error(),
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|
||
|
|
return Errorf(codes.Unknown, "%v", err)
|
||
|
|
}
|
||
|
|
|
||
|
|
// 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:
|
||
|
|
return codes.Canceled
|
||
|
|
case context.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
|
||
|
|
}
|
||
|
|
|
||
|
|
// SupportPackageIsVersion3 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 SupportPackageIsVersion3 = true
|