ledisdb/ledis/t_zset.go

663 lines
13 KiB
Go

package ledis
import (
"bytes"
"encoding/binary"
"errors"
"github.com/siddontang/go-leveldb/leveldb"
)
const (
MinScore int64 = -1<<63 + 1
MaxScore int64 = 1<<63 - 1
)
type ScorePair struct {
Score int64
Member []byte
}
var errZSizeKey = errors.New("invalid zsize key")
var errZSetKey = errors.New("invalid zset key")
var errZScoreKey = errors.New("invalid zscore key")
var errScoreOverflow = errors.New("zset score overflow")
const (
zsetNScoreSep byte = '<'
zsetPScoreSep byte = zsetNScoreSep + 1
zsetStopScoreSep byte = zsetPScoreSep + 1
zsetStartMemSep byte = ':'
zsetStopMemSep byte = zsetStartMemSep + 1
)
func checkZSetKMSize(key []byte, member []byte) error {
if len(key) > MaxKeySize {
return ErrKeySize
} else if len(member) > MaxZSetMemberSize {
return ErrZSetMemberSize
}
return nil
}
func (db *DB) zEncodeSizeKey(key []byte) []byte {
buf := make([]byte, len(key)+2)
buf[0] = db.index
buf[1] = zSizeType
copy(buf[2:], key)
return buf
}
func (db *DB) zDecodeSizeKey(ek []byte) ([]byte, error) {
if len(ek) < 2 || ek[0] != db.index || ek[1] != zSizeType {
return nil, errZSizeKey
}
return ek[2:], nil
}
func (db *DB) zEncodeSetKey(key []byte, member []byte) []byte {
buf := make([]byte, len(key)+len(member)+4)
pos := 0
buf[pos] = db.index
pos++
buf[pos] = zsetType
pos++
binary.BigEndian.PutUint16(buf[pos:], uint16(len(key)))
pos += 2
copy(buf[pos:], key)
pos += len(key)
copy(buf[pos:], member)
return buf
}
func (db *DB) zDecodeSetKey(ek []byte) ([]byte, []byte, error) {
if len(ek) < 4 || ek[0] != db.index || ek[1] != zsetType {
return nil, nil, errZSetKey
}
keyLen := int(binary.BigEndian.Uint16(ek[2:]))
if keyLen+4 > len(ek) {
return nil, nil, errZSetKey
}
key := ek[4 : 4+keyLen]
member := ek[4+keyLen:]
return key, member, nil
}
func (db *DB) zEncodeScoreKey(key []byte, member []byte, score int64) []byte {
buf := make([]byte, len(key)+len(member)+14)
pos := 0
buf[pos] = db.index
pos++
buf[pos] = zScoreType
pos++
binary.BigEndian.PutUint16(buf[pos:], uint16(len(key)))
pos += 2
copy(buf[pos:], key)
pos += len(key)
if score < 0 {
buf[pos] = zsetNScoreSep
} else {
buf[pos] = zsetPScoreSep
}
pos++
binary.BigEndian.PutUint64(buf[pos:], uint64(score))
pos += 8
buf[pos] = zsetStartMemSep
pos++
copy(buf[pos:], member)
return buf
}
func (db *DB) zEncodeStartScoreKey(key []byte, score int64) []byte {
return db.zEncodeScoreKey(key, nil, score)
}
func (db *DB) zEncodeStopScoreKey(key []byte, score int64) []byte {
k := db.zEncodeScoreKey(key, nil, score)
k[len(k)-1] = zsetStopMemSep
return k
}
func (db *DB) zDecodeScoreKey(ek []byte) (key []byte, member []byte, score int64, err error) {
if len(ek) < 14 || ek[0] != db.index || ek[1] != zScoreType {
err = errZScoreKey
return
}
keyLen := int(binary.BigEndian.Uint16(ek[2:]))
if keyLen+14 > len(ek) {
err = errZScoreKey
return
}
key = ek[4 : 4+keyLen]
pos := 4 + keyLen
if (ek[pos] != zsetNScoreSep) && (ek[pos] != zsetPScoreSep) {
err = errZScoreKey
return
}
pos++
score = int64(binary.BigEndian.Uint64(ek[pos:]))
pos += 8
if ek[pos] != zsetStartMemSep {
err = errZScoreKey
return
}
pos++
member = ek[pos:]
return
}
func (db *DB) zSetItem(key []byte, score int64, member []byte) (int64, error) {
if score <= MinScore || score >= MaxScore {
return 0, errScoreOverflow
}
t := db.zsetTx
var exists int64 = 0
ek := db.zEncodeSetKey(key, member)
if v, err := db.db.Get(ek); err != nil {
return 0, err
} else if v != nil {
exists = 1
if s, err := Int64(v, err); err != nil {
return 0, err
} else {
sk := db.zEncodeScoreKey(key, member, s)
t.Delete(sk)
}
}
t.Put(ek, PutInt64(score))
sk := db.zEncodeScoreKey(key, member, score)
t.Put(sk, []byte{})
return exists, nil
}
func (db *DB) zDelItem(key []byte, member []byte, skipDelScore bool) (int64, error) {
t := db.zsetTx
ek := db.zEncodeSetKey(key, member)
if v, err := db.db.Get(ek); err != nil {
return 0, err
} else if v == nil {
//not exists
return 0, nil
} else {
//exists
if !skipDelScore {
//we must del score
if s, err := Int64(v, err); err != nil {
return 0, err
} else {
sk := db.zEncodeScoreKey(key, member, s)
t.Delete(sk)
}
}
}
t.Delete(ek)
return 1, nil
}
func (db *DB) ZAdd(key []byte, args ...ScorePair) (int64, error) {
if len(args) == 0 {
return 0, nil
}
t := db.zsetTx
t.Lock()
defer t.Unlock()
var num int64 = 0
for i := 0; i < len(args); i++ {
score := args[i].Score
member := args[i].Member
if err := checkZSetKMSize(key, member); err != nil {
return 0, err
}
if n, err := db.zSetItem(key, score, member); err != nil {
return 0, err
} else if n == 0 {
//add new
num++
}
}
if _, err := db.zIncrSize(key, num); err != nil {
return 0, err
}
//todo add binlog
err := t.Commit()
return num, err
}
func (db *DB) zIncrSize(key []byte, delta int64) (int64, error) {
t := db.zsetTx
sk := db.zEncodeSizeKey(key)
size, err := Int64(db.db.Get(sk))
if err != nil {
return 0, err
} else {
size += delta
if size <= 0 {
size = 0
t.Delete(sk)
} else {
t.Put(sk, PutInt64(size))
}
}
return size, nil
}
func (db *DB) ZCard(key []byte) (int64, error) {
if err := checkKeySize(key); err != nil {
return 0, err
}
sk := db.zEncodeSizeKey(key)
return Int64(db.db.Get(sk))
}
func (db *DB) ZScore(key []byte, member []byte) ([]byte, error) {
if err := checkZSetKMSize(key, member); err != nil {
return nil, err
}
k := db.zEncodeSetKey(key, member)
score, err := Int64(db.db.Get(k))
if err != nil {
return nil, err
}
return StrPutInt64(score), nil
}
func (db *DB) ZRem(key []byte, members ...[]byte) (int64, error) {
if len(members) == 0 {
return 0, nil
}
t := db.zsetTx
t.Lock()
defer t.Unlock()
var num int64 = 0
for i := 0; i < len(members); i++ {
if err := checkZSetKMSize(key, members[i]); err != nil {
return 0, err
}
if n, err := db.zDelItem(key, members[i], false); err != nil {
return 0, err
} else if n == 1 {
num++
}
}
if _, err := db.zIncrSize(key, -num); err != nil {
return 0, err
}
err := t.Commit()
return num, err
}
func (db *DB) ZIncrBy(key []byte, delta int64, member []byte) ([]byte, error) {
if err := checkZSetKMSize(key, member); err != nil {
return nil, err
}
t := db.zsetTx
t.Lock()
defer t.Unlock()
ek := db.zEncodeSetKey(key, member)
var score int64 = delta
v, err := db.db.Get(ek)
if err != nil {
return nil, err
} else if v != nil {
if s, err := Int64(v, err); err != nil {
return nil, err
} else {
sk := db.zEncodeScoreKey(key, member, s)
t.Delete(sk)
score = s + delta
if score >= MaxScore || score <= MinScore {
return nil, errScoreOverflow
}
}
} else {
db.zIncrSize(key, 1)
}
t.Put(ek, PutInt64(score))
sk := db.zEncodeScoreKey(key, member, score)
t.Put(sk, []byte{})
err = t.Commit()
return StrPutInt64(score), err
}
func (db *DB) ZCount(key []byte, min int64, max int64) (int64, error) {
if err := checkKeySize(key); err != nil {
return 0, err
}
minKey := db.zEncodeStartScoreKey(key, min)
maxKey := db.zEncodeStopScoreKey(key, max)
rangeType := leveldb.RangeROpen
it := db.db.Iterator(minKey, maxKey, rangeType, 0, -1)
var n int64 = 0
for ; it.Valid(); it.Next() {
n++
}
it.Close()
return n, nil
}
func (db *DB) zrank(key []byte, member []byte, reverse bool) (int64, error) {
if err := checkZSetKMSize(key, member); err != nil {
return 0, err
}
k := db.zEncodeSetKey(key, member)
if v, err := db.db.Get(k); err != nil {
return 0, err
} else if v == nil {
return -1, nil
} else {
if s, err := Int64(v, err); err != nil {
return 0, err
} else {
var it *leveldb.Iterator
sk := db.zEncodeScoreKey(key, member, s)
if !reverse {
minKey := db.zEncodeStartScoreKey(key, MinScore)
it = db.db.Iterator(minKey, sk, leveldb.RangeClose, 0, -1)
} else {
maxKey := db.zEncodeStopScoreKey(key, MaxScore)
it = db.db.RevIterator(sk, maxKey, leveldb.RangeClose, 0, -1)
}
var lastKey []byte = nil
var n int64 = 0
for ; it.Valid(); it.Next() {
n++
lastKey = it.Key()
}
it.Close()
if _, m, _, err := db.zDecodeScoreKey(lastKey); err == nil && bytes.Equal(m, member) {
n--
return n, nil
}
}
}
return -1, nil
}
func (db *DB) zIterator(key []byte, min int64, max int64, offset int, limit int, reverse bool) *leveldb.Iterator {
minKey := db.zEncodeStartScoreKey(key, min)
maxKey := db.zEncodeStopScoreKey(key, max)
if !reverse {
return db.db.Iterator(minKey, maxKey, leveldb.RangeClose, offset, limit)
} else {
return db.db.RevIterator(minKey, maxKey, leveldb.RangeClose, offset, limit)
}
}
func (db *DB) zRemRange(key []byte, min int64, max int64, offset int, limit int) (int64, error) {
if len(key) > MaxKeySize {
return 0, ErrKeySize
}
t := db.zsetTx
t.Lock()
defer t.Unlock()
it := db.zIterator(key, min, max, offset, limit, false)
var num int64 = 0
for ; it.Valid(); it.Next() {
k := it.Key()
_, m, _, err := db.zDecodeScoreKey(k)
if err != nil {
continue
}
if n, err := db.zDelItem(key, m, true); err != nil {
return 0, err
} else if n == 1 {
num++
}
t.Delete(k)
}
if _, err := db.zIncrSize(key, -num); err != nil {
return 0, err
}
//todo add binlog
err := t.Commit()
return num, err
}
func (db *DB) zReverse(s []interface{}, withScores bool) []interface{} {
if withScores {
for i, j := 0, len(s)-2; i < j; i, j = i+2, j-2 {
s[i], s[j] = s[j], s[i]
s[i+1], s[j+1] = s[j+1], s[i+1]
}
} else {
for i, j := 0, len(s)-1; i < j; i, j = i+1, j-1 {
s[i], s[j] = s[j], s[i]
}
}
return s
}
func (db *DB) zRange(key []byte, min int64, max int64, withScores bool, offset int, limit int, reverse bool) ([]interface{}, error) {
if len(key) > MaxKeySize {
return nil, ErrKeySize
}
if offset < 0 {
return []interface{}{}, nil
}
nv := 64
if limit > 0 {
nv = limit
}
if withScores {
nv = 2 * nv
}
v := make([]interface{}, 0, nv)
var it *leveldb.Iterator
//if reverse and offset is 0, limit < 0, we may use forward iterator then reverse
//because leveldb iterator prev is slower than next
if !reverse || (offset == 0 && limit < 0) {
it = db.zIterator(key, min, max, offset, limit, false)
} else {
it = db.zIterator(key, min, max, offset, limit, true)
}
for ; it.Valid(); it.Next() {
_, m, s, err := db.zDecodeScoreKey(it.Key())
//may be we will check key equal?
if err != nil {
continue
}
v = append(v, m)
if withScores {
v = append(v, StrPutInt64(s))
}
}
if reverse && (offset == 0 && limit < 0) {
v = db.zReverse(v, withScores)
}
return v, nil
}
func (db *DB) zParseLimit(key []byte, start int, stop int) (offset int, limit int, err error) {
if start < 0 || stop < 0 {
//refer redis implementation
var size int64
size, err = db.ZCard(key)
if err != nil {
return
}
llen := int(size)
if start < 0 {
start = llen + start
}
if stop < 0 {
stop = llen + stop
}
if start < 0 {
start = 0
}
if start >= llen {
offset = -1
return
}
}
if start > stop {
offset = -1
return
}
offset = start
limit = (stop - start) + 1
return
}
func (db *DB) ZClear(key []byte) (int64, error) {
return db.zRemRange(key, MinScore, MaxScore, 0, -1)
}
func (db *DB) ZRange(key []byte, start int, stop int, withScores bool) ([]interface{}, error) {
return db.ZRangeGeneric(key, start, stop, withScores, false)
}
//min and max must be inclusive
//if no limit, set offset = 0 and count = -1
func (db *DB) ZRangeByScore(key []byte, min int64, max int64,
withScores bool, offset int, count int) ([]interface{}, error) {
return db.ZRangeByScoreGeneric(key, min, max, withScores, offset, count, false)
}
func (db *DB) ZRank(key []byte, member []byte) (int64, error) {
return db.zrank(key, member, false)
}
func (db *DB) ZRemRangeByRank(key []byte, start int, stop int) (int64, error) {
offset, limit, err := db.zParseLimit(key, start, stop)
if err != nil {
return 0, err
}
return db.zRemRange(key, MinScore, MaxScore, offset, limit)
}
//min and max must be inclusive
func (db *DB) ZRemRangeByScore(key []byte, min int64, max int64) (int64, error) {
return db.zRemRange(key, min, max, 0, -1)
}
func (db *DB) ZRevRange(key []byte, start int, stop int, withScores bool) ([]interface{}, error) {
return db.ZRangeGeneric(key, start, stop, withScores, true)
}
func (db *DB) ZRevRank(key []byte, member []byte) (int64, error) {
return db.zrank(key, member, true)
}
//min and max must be inclusive
//if no limit, set offset = 0 and count = -1
func (db *DB) ZRevRangeByScore(key []byte, min int64, max int64,
withScores bool, offset int, count int) ([]interface{}, error) {
return db.ZRangeByScoreGeneric(key, min, max, withScores, offset, count, true)
}
func (db *DB) ZRangeGeneric(key []byte, start int, stop int,
withScores bool, reverse bool) ([]interface{}, error) {
offset, limit, err := db.zParseLimit(key, start, stop)
if err != nil {
return nil, err
}
return db.zRange(key, MinScore, MaxScore, withScores, offset, limit, reverse)
}
//min and max must be inclusive
//if no limit, set offset = 0 and count = -1
func (db *DB) ZRangeByScoreGeneric(key []byte, min int64, max int64,
withScores bool, offset int, count int, reverse bool) ([]interface{}, error) {
return db.zRange(key, min, max, withScores, offset, count, reverse)
}