package pgproto3 import ( "bytes" "encoding/binary" "encoding/json" "github.com/jackc/pgx/v5/internal/pgio" ) type NotificationResponse struct { PID uint32 Channel string Payload string } // Backend identifies this message as sendable by the PostgreSQL backend. func (*NotificationResponse) Backend() {} // Decode decodes src into dst. src must contain the complete message with the exception of the initial 1 byte message // type identifier and 4 byte message length. func (dst *NotificationResponse) Decode(src []byte) error { buf := bytes.NewBuffer(src) if buf.Len() < 4 { return &invalidMessageFormatErr{messageType: "NotificationResponse", details: "too short"} } pid := binary.BigEndian.Uint32(buf.Next(4)) b, err := buf.ReadBytes(0) if err != nil { return err } channel := string(b[:len(b)-1]) b, err = buf.ReadBytes(0) if err != nil { return err } payload := string(b[:len(b)-1]) *dst = NotificationResponse{PID: pid, Channel: channel, Payload: payload} return nil } // Encode encodes src into dst. dst will include the 1 byte message type identifier and the 4 byte message length. func (src *NotificationResponse) Encode(dst []byte) []byte { dst = append(dst, 'A') sp := len(dst) dst = pgio.AppendInt32(dst, -1) dst = pgio.AppendUint32(dst, src.PID) dst = append(dst, src.Channel...) dst = append(dst, 0) dst = append(dst, src.Payload...) dst = append(dst, 0) pgio.SetInt32(dst[sp:], int32(len(dst[sp:]))) return dst } // MarshalJSON implements encoding/json.Marshaler. func (src NotificationResponse) MarshalJSON() ([]byte, error) { return json.Marshal(struct { Type string PID uint32 Channel string Payload string }{ Type: "NotificationResponse", PID: src.PID, Channel: src.Channel, Payload: src.Payload, }) }