github.com/jackc/pgx/v5@v5.5.5/pgproto3/copy_data.go (about)

     1  package pgproto3
     2  
     3  import (
     4  	"encoding/hex"
     5  	"encoding/json"
     6  )
     7  
     8  type CopyData struct {
     9  	Data []byte
    10  }
    11  
    12  // Backend identifies this message as sendable by the PostgreSQL backend.
    13  func (*CopyData) Backend() {}
    14  
    15  // Frontend identifies this message as sendable by a PostgreSQL frontend.
    16  func (*CopyData) Frontend() {}
    17  
    18  // Decode decodes src into dst. src must contain the complete message with the exception of the initial 1 byte message
    19  // type identifier and 4 byte message length.
    20  func (dst *CopyData) Decode(src []byte) error {
    21  	dst.Data = src
    22  	return nil
    23  }
    24  
    25  // Encode encodes src into dst. dst will include the 1 byte message type identifier and the 4 byte message length.
    26  func (src *CopyData) Encode(dst []byte) ([]byte, error) {
    27  	dst, sp := beginMessage(dst, 'd')
    28  	dst = append(dst, src.Data...)
    29  	return finishMessage(dst, sp)
    30  }
    31  
    32  // MarshalJSON implements encoding/json.Marshaler.
    33  func (src CopyData) MarshalJSON() ([]byte, error) {
    34  	return json.Marshal(struct {
    35  		Type string
    36  		Data string
    37  	}{
    38  		Type: "CopyData",
    39  		Data: hex.EncodeToString(src.Data),
    40  	})
    41  }
    42  
    43  // UnmarshalJSON implements encoding/json.Unmarshaler.
    44  func (dst *CopyData) UnmarshalJSON(data []byte) error {
    45  	// Ignore null, like in the main JSON package.
    46  	if string(data) == "null" {
    47  		return nil
    48  	}
    49  
    50  	var msg struct {
    51  		Data string
    52  	}
    53  	if err := json.Unmarshal(data, &msg); err != nil {
    54  		return err
    55  	}
    56  
    57  	dst.Data = []byte(msg.Data)
    58  	return nil
    59  }