trpc.group/trpc-go/trpc-go@v1.0.3/codec/codec.go (about)

     1  //
     2  //
     3  // Tencent is pleased to support the open source community by making tRPC available.
     4  //
     5  // Copyright (C) 2023 THL A29 Limited, a Tencent company.
     6  // All rights reserved.
     7  //
     8  // If you have downloaded a copy of the tRPC source code from Tencent,
     9  // please note that tRPC source code is licensed under the  Apache 2.0 License,
    10  // A copy of the Apache 2.0 License is included in this file.
    11  //
    12  //
    13  
    14  // Package codec defines the business communication protocol of
    15  // packing and unpacking.
    16  package codec
    17  
    18  import (
    19  	"sync"
    20  
    21  	trpcpb "trpc.group/trpc/trpc-protocol/pb/go/trpc"
    22  )
    23  
    24  // RequestType is the type of client request, such as SendAndRecv，SendOnly.
    25  type RequestType int
    26  
    27  const (
    28  	// SendAndRecv means send one request and receive one response.
    29  	SendAndRecv = RequestType(trpcpb.TrpcCallType_TRPC_UNARY_CALL)
    30  	// SendOnly means only send request, no response.
    31  	SendOnly = RequestType(trpcpb.TrpcCallType_TRPC_ONEWAY_CALL)
    32  )
    33  
    34  // Codec defines the interface of business communication protocol,
    35  // which contains head and body. It only parses the body in binary,
    36  // and then the business body struct will be handled by serializer.
    37  // In common, the body's protocol is pb, json, etc. Specially,
    38  // we can register our own serializer to handle other body type.
    39  type Codec interface {
    40  	// Encode pack the body into binary buffer.
    41  	// client: Encode(msg, reqBody)(request-buffer, err)
    42  	// server: Encode(msg, rspBody)(response-buffer, err)
    43  	Encode(message Msg, body []byte) (buffer []byte, err error)
    44  
    45  	// Decode unpack the body from binary buffer
    46  	// server: Decode(msg, request-buffer)(reqBody, err)
    47  	// client: Decode(msg, response-buffer)(rspBody, err)
    48  	Decode(message Msg, buffer []byte) (body []byte, err error)
    49  }
    50  
    51  var (
    52  	clientCodecs = make(map[string]Codec)
    53  	serverCodecs = make(map[string]Codec)
    54  	lock         sync.RWMutex
    55  )
    56  
    57  // Register defines the logic of register an codec by name. It will be
    58  // called by init function defined by third package. If there is no server codec,
    59  // the second param serverCodec can be nil.
    60  func Register(name string, serverCodec Codec, clientCodec Codec) {
    61  	lock.Lock()
    62  	serverCodecs[name] = serverCodec
    63  	clientCodecs[name] = clientCodec
    64  	lock.Unlock()
    65  }
    66  
    67  // GetServer returns the server codec by name.
    68  func GetServer(name string) Codec {
    69  	lock.RLock()
    70  	c := serverCodecs[name]
    71  	lock.RUnlock()
    72  	return c
    73  }
    74  
    75  // GetClient returns the client codec by name.
    76  func GetClient(name string) Codec {
    77  	lock.RLock()
    78  	c := clientCodecs[name]
    79  	lock.RUnlock()
    80  	return c
    81  }