From eec14806d2d3ebb283313f916c1503ba474eb0fa Mon Sep 17 00:00:00 2001
From: siddontang <siddontang@gmail.com>
Date: Fri, 11 Jul 2014 13:28:34 +0800
Subject: [PATCH] add support for read and print bin log

---
 ledis/binlog_util.go | 148 +++++++++++++++++++++++++++++++++++++++++++
 ledis/replication.go |  25 ++++++--
 2 files changed, 169 insertions(+), 4 deletions(-)

diff --git a/ledis/binlog_util.go b/ledis/binlog_util.go
index bc1cd63..766d3e6 100644
--- a/ledis/binlog_util.go
+++ b/ledis/binlog_util.go
@@ -3,6 +3,8 @@ package ledis
 import (
 	"encoding/binary"
 	"errors"
+	"fmt"
+	"strconv"
 )
 
 var (
@@ -60,3 +62,149 @@ func encodeBinLogCommand(commandType uint8, args ...[]byte) []byte {
 func decodeBinLogCommand(sz []byte) (uint8, [][]byte, error) {
 	return 0, nil, errBinLogCommandType
 }
+
+func FormatBinLogEvent(event []byte) (string, error) {
+	logType := uint8(event[0])
+
+	var err error
+	var k []byte
+	var v []byte
+
+	var buf []byte = make([]byte, 0, 1024)
+
+	switch logType {
+	case BinLogTypePut:
+		k, v, err = decodeBinLogPut(event)
+		buf = append(buf, "PUT "...)
+	case BinLogTypeDeletion:
+		k, err = decodeBinLogDelete(event)
+		buf = append(buf, "DELETE "...)
+	default:
+		err = errInvalidBinLogEvent
+	}
+
+	if err != nil {
+		return "", err
+	}
+
+	if buf, err = formatDataKey(buf, k); err != nil {
+		return "", err
+	}
+
+	if v != nil && len(v) != 0 {
+		buf = append(buf, fmt.Sprintf(" %q", v)...)
+	}
+
+	return String(buf), nil
+}
+
+func formatDataKey(buf []byte, k []byte) ([]byte, error) {
+	if len(k) < 2 {
+		return nil, errInvalidBinLogEvent
+	}
+
+	buf = append(buf, fmt.Sprintf("DB:%2d ", k[0])...)
+	buf = append(buf, fmt.Sprintf("%s ", TypeName[k[1]])...)
+
+	db := new(DB)
+	db.index = k[0]
+
+	//to do format at respective place
+
+	switch k[1] {
+	case KVType:
+		if key, err := db.decodeKVKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+		}
+	case HashType:
+		if key, field, err := db.hDecodeHashKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+			buf = append(buf, ' ')
+			buf = strconv.AppendQuote(buf, String(field))
+		}
+	case HSizeType:
+		if key, err := db.hDecodeSizeKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+		}
+	case ListType:
+		if key, seq, err := db.lDecodeListKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+			buf = append(buf, ' ')
+			buf = strconv.AppendInt(buf, int64(seq), 10)
+		}
+	case LMetaType:
+		if key, err := db.lDecodeMetaKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+		}
+	case ZSetType:
+		if key, m, err := db.zDecodeSetKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+			buf = append(buf, ' ')
+			buf = strconv.AppendQuote(buf, String(m))
+		}
+	case ZSizeType:
+		if key, err := db.zDecodeSizeKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+		}
+	case ZScoreType:
+		if key, m, score, err := db.zDecodeScoreKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+			buf = append(buf, ' ')
+			buf = strconv.AppendQuote(buf, String(m))
+			buf = append(buf, ' ')
+			buf = strconv.AppendInt(buf, score, 10)
+		}
+	case BitType:
+		if key, seq, err := db.bDecodeBinKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+			buf = append(buf, ' ')
+			buf = strconv.AppendUint(buf, uint64(seq), 10)
+		}
+	case BitMetaType:
+		if key, err := db.bDecodeMetaKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = strconv.AppendQuote(buf, String(key))
+		}
+	case ExpTimeType:
+		if tp, key, t, err := db.expDecodeTimeKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = append(buf, TypeName[tp]...)
+			buf = append(buf, ' ')
+			buf = strconv.AppendQuote(buf, String(key))
+			buf = append(buf, ' ')
+			buf = strconv.AppendInt(buf, t, 10)
+		}
+	case ExpMetaType:
+		if tp, key, err := db.expDecodeMetaKey(k); err != nil {
+			return nil, err
+		} else {
+			buf = append(buf, TypeName[tp]...)
+			buf = append(buf, ' ')
+			buf = strconv.AppendQuote(buf, String(key))
+		}
+	default:
+		return nil, errInvalidBinLogEvent
+	}
+
+	return buf, nil
+}
diff --git a/ledis/replication.go b/ledis/replication.go
index e19da6a..bd6c192 100644
--- a/ledis/replication.go
+++ b/ledis/replication.go
@@ -10,6 +10,10 @@ import (
 	"os"
 )
 
+var (
+	ErrSkipEvent = errors.New("skip to next event")
+)
+
 var (
 	errInvalidBinLogEvent = errors.New("invalid binglog event")
 	errInvalidBinLogFile  = errors.New("invalid binlog file")
@@ -71,7 +75,7 @@ func (l *Ledis) replicateCommandEvent(event []byte) error {
 	return errors.New("command event not supported now")
 }
 
-func (l *Ledis) ReplicateFromReader(rb io.Reader) error {
+func ReadEventFromReader(rb io.Reader, f func(createTime uint32, event []byte) error) error {
 	var createTime uint32
 	var dataLen uint32
 	var dataBuf bytes.Buffer
@@ -94,9 +98,9 @@ func (l *Ledis) ReplicateFromReader(rb io.Reader) error {
 			return err
 		}
 
-		err = l.ReplicateEvent(dataBuf.Bytes())
-		if err != nil {
-			log.Fatal("replication error %s, skip to next", err.Error())
+		err = f(createTime, dataBuf.Bytes())
+		if err != nil && err != ErrSkipEvent {
+			return err
 		}
 
 		dataBuf.Reset()
@@ -105,6 +109,19 @@ func (l *Ledis) ReplicateFromReader(rb io.Reader) error {
 	return nil
 }
 
+func (l *Ledis) ReplicateFromReader(rb io.Reader) error {
+	f := func(createTime uint32, event []byte) error {
+		err := l.ReplicateEvent(event)
+		if err != nil {
+			log.Fatal("replication error %s, skip to next", err.Error())
+			return ErrSkipEvent
+		}
+		return nil
+	}
+
+	return ReadEventFromReader(rb, f)
+}
+
 func (l *Ledis) ReplicateFromData(data []byte) error {
 	rb := bytes.NewReader(data)