pgproxy for query, parse, bind messages

pgproxy.go

package main

import (
	"encoding/hex"
	"fmt"
	"github.com/rueian/pgbroker/backend"
	"github.com/rueian/pgbroker/message"
	"github.com/rueian/pgbroker/proxy"
	"net"
)

func main() {
	ln, err := net.Listen("tcp", ":5433")
	if err != nil {
		panic(err)
	}

	clientMessageHandlers := proxy.NewClientMessageHandlers()
	serverMessageHandlers := proxy.NewServerMessageHandlers()

	serverMessageHandlers.AddHandleDataRow(func(ms *proxy.Ctx, msg *message.DataRow) (row *message.DataRow, err error) {
		for i, column := range msg.ColumnValues {
			if len(ms.RowDescription.Fields) == 0 || ms.RowDescription.Fields[i].FormatCode == 0 {
				fmt.Printf("Result DataRaw: column=%d format=text len=%d value=%s\n", i, column.DataLength(), string(column.DataBytes()))
			} else {
				fmt.Printf("Result DataRaw: column=%d format=byte len=%d hex=%s\n", i, column.DataLength(), hex.EncodeToString(column.DataBytes()))
			}
		}
		return msg, nil
	})
	clientMessageHandlers.AddHandleQuery(func(ctx *proxy.Ctx, msg *message.Query) (query *message.Query, e error) {
		fmt.Printf("Simple Query: len=%d query=%s\n", len(msg.QueryString), msg.QueryString)
		return msg, nil
	})
	clientMessageHandlers.AddHandleParse(func(md *proxy.Ctx, msg *message.Parse) (parse *message.Parse, err error) {
		fmt.Printf("Parse Query: name=%s query=%s\n", msg.PreparedStatementName, msg.QueryString)
		return msg, nil
	})
	clientMessageHandlers.AddHandleBind(func(md *proxy.Ctx, msg *message.Bind) (bind *message.Bind, err error) {
		for i, value := range msg.ParameterValues {
			if len(msg.ParameterFormatCodes) == 0 || msg.ParameterFormatCodes[i] == 0 {
				fmt.Printf("Bind Parameter: %d format=text len=%d value=%s\n", i, value.DataLength(), string(value.DataBytes()))
			} else {
				fmt.Printf("Bind Parameter: %d format=byte len=%d hex=%s\n", i, value.DataLength(), hex.EncodeToString(value.DataBytes()))
			}
		}
		md.RowDescription = &message.RowDescription{Fields: make([]message.Field, len(msg.ResultColumnFormatCodes))}
		for i, format := range msg.ResultColumnFormatCodes {
			md.RowDescription.Fields[i].FormatCode = format
			if format == 0 {
				fmt.Printf("Bind ResultFormatCodes: column=%d format=text\n", i)
			} else {
				fmt.Printf("Bind ResultFormatCodes: column=%d format=byte\n", i)
			}
		}
		if len(msg.ResultColumnFormatCodes) == 0 {
			fmt.Printf("Bind ResultFormatCodes: no result format codes\n")
		}
		return msg, nil
	})

	server := proxy.Server{
		PGResolver:            backend.NewStaticPGResolver("127.0.0.1:5432"),
		ConnInfoStore:         backend.NewInMemoryConnInfoStore(),
		ClientMessageHandlers: clientMessageHandlers,
		ServerMessageHandlers: serverMessageHandlers,
	}

	server.Serve(ln)
}