go.uber.org/yarpc@v1.72.1/transport/grpc/codec.go (about)

     1  // Copyright (c) 2022 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package grpc
    22  
    23  import "fmt"
    24  
    25  // customCodec pass bytes to/from the wire without modification.
    26  type customCodec struct{}
    27  
    28  // Marshal takes a []byte and passes it through as a []byte.
    29  func (customCodec) Marshal(obj interface{}) ([]byte, error) {
    30  	switch value := obj.(type) {
    31  	case []byte:
    32  		return value, nil
    33  	default:
    34  		return nil, newCustomCodecMarshalCastError(obj)
    35  	}
    36  }
    37  
    38  // Unmarshal takes a []byte pointer as obj and points it to data.
    39  func (customCodec) Unmarshal(data []byte, obj interface{}) error {
    40  	switch value := obj.(type) {
    41  	case *[]byte:
    42  		*value = data
    43  		return nil
    44  	default:
    45  		return newCustomCodecUnmarshalCastError(obj)
    46  	}
    47  }
    48  
    49  func (customCodec) String() string {
    50  	// Setting this to what amounts to a nonsense value.
    51  	// The encoding should always be inferred from the headers.
    52  	// Setting this to a name that is not an encoding will assure
    53  	// we get an error if this is used as the encoding value.
    54  	return "yarpc"
    55  }
    56  
    57  func newCustomCodecMarshalCastError(actualObject interface{}) error {
    58  	return fmt.Errorf("expected object to be of type []byte but got %T", actualObject)
    59  }
    60  
    61  func newCustomCodecUnmarshalCastError(actualObject interface{}) error {
    62  	return fmt.Errorf("expected object to be of type *[]byte but got %T", actualObject)
    63  }