parse.go (2033B)
1 package pgproto3 2 3 import ( 4 "bytes" 5 "encoding/binary" 6 "encoding/json" 7 8 "github.com/jackc/pgx/v5/internal/pgio" 9 ) 10 11 type Parse struct { 12 Name string 13 Query string 14 ParameterOIDs []uint32 15 } 16 17 // Frontend identifies this message as sendable by a PostgreSQL frontend. 18 func (*Parse) Frontend() {} 19 20 // Decode decodes src into dst. src must contain the complete message with the exception of the initial 1 byte message 21 // type identifier and 4 byte message length. 22 func (dst *Parse) Decode(src []byte) error { 23 *dst = Parse{} 24 25 buf := bytes.NewBuffer(src) 26 27 b, err := buf.ReadBytes(0) 28 if err != nil { 29 return err 30 } 31 dst.Name = string(b[:len(b)-1]) 32 33 b, err = buf.ReadBytes(0) 34 if err != nil { 35 return err 36 } 37 dst.Query = string(b[:len(b)-1]) 38 39 if buf.Len() < 2 { 40 return &invalidMessageFormatErr{messageType: "Parse"} 41 } 42 parameterOIDCount := int(binary.BigEndian.Uint16(buf.Next(2))) 43 44 for i := 0; i < parameterOIDCount; i++ { 45 if buf.Len() < 4 { 46 return &invalidMessageFormatErr{messageType: "Parse"} 47 } 48 dst.ParameterOIDs = append(dst.ParameterOIDs, binary.BigEndian.Uint32(buf.Next(4))) 49 } 50 51 return nil 52 } 53 54 // Encode encodes src into dst. dst will include the 1 byte message type identifier and the 4 byte message length. 55 func (src *Parse) Encode(dst []byte) []byte { 56 dst = append(dst, 'P') 57 sp := len(dst) 58 dst = pgio.AppendInt32(dst, -1) 59 60 dst = append(dst, src.Name...) 61 dst = append(dst, 0) 62 dst = append(dst, src.Query...) 63 dst = append(dst, 0) 64 65 dst = pgio.AppendUint16(dst, uint16(len(src.ParameterOIDs))) 66 for _, oid := range src.ParameterOIDs { 67 dst = pgio.AppendUint32(dst, oid) 68 } 69 70 pgio.SetInt32(dst[sp:], int32(len(dst[sp:]))) 71 72 return dst 73 } 74 75 // MarshalJSON implements encoding/json.Marshaler. 76 func (src Parse) MarshalJSON() ([]byte, error) { 77 return json.Marshal(struct { 78 Type string 79 Name string 80 Query string 81 ParameterOIDs []uint32 82 }{ 83 Type: "Parse", 84 Name: src.Name, 85 Query: src.Query, 86 ParameterOIDs: src.ParameterOIDs, 87 }) 88 }