本文整理汇总了Golang中github.com/syndtr/goleveldb/leveldb/iterator.Iterator.Next方法的典型用法代码示例。如果您正苦于以下问题:Golang Iterator.Next方法的具体用法?Golang Iterator.Next怎么用?Golang Iterator.Next使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类github.com/syndtr/goleveldb/leveldb/iterator.Iterator
的用法示例。
在下文中一共展示了Iterator.Next方法的8个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Golang代码示例。
示例1: createFrom
// Builds table from src iterator.
func (t *tOps) createFrom(src iterator.Iterator) (f *tFile, n int, err error) {
w, err := t.create()
if err != nil {
return
}
defer func() {
if err != nil {
w.drop()
}
}()
for src.Next() {
err = w.append(src.Key(), src.Value())
if err != nil {
return
}
}
err = src.Error()
if err != nil {
return
}
n = w.tw.EntriesLen()
f, err = w.finish()
return
}
示例2: eoi
func (h *blockHarness) eoi(pref string, iter iterator.Iterator) {
if iter.Next() {
h.t.Fatalf("block: %sNext: expect eoi", pref)
} else if err := iter.Error(); err != nil {
h.t.Fatalf("block: %sNext: expect eoi but got error, err=%v", pref, err)
}
}
示例3: list
func list(c *cli.Context) {
dbPath := c.GlobalString("path")
pwd, err := os.Getwd()
dbPath = path.Join(pwd, dbPath)
options := &opt.Options{ErrorIfMissing: true}
db, err := leveldb.OpenFile(dbPath, options)
if err != nil {
msg := fmt.Sprintf("%s %s", err, dbPath)
panic(msg)
}
fmt.Println("using database:", dbPath)
defer db.Close()
var iter iterator.Iterator
fmt.Println("Listing reading keys...")
iter = db.NewIterator(&dbutil.Range{Start: []byte("/reading/RF12:"), Limit: []byte("/reading/RF12~")}, nil)
for iter.Next() {
key := string(iter.Key())
fmt.Println(key)
}
iter.Release()
//err = iter.Error()
}
示例4: newUnionIter
func newUnionIter(dirtyIt iterator.Iterator, snapshotIt Iterator) *UnionIter {
it := &UnionIter{
dirtyIt: dirtyIt,
snapshotIt: snapshotIt,
// leveldb use next for checking valid...
dirtyValid: dirtyIt.Next(),
snapshotValid: snapshotIt.Valid(),
}
it.updateCur()
return it
}
示例5: nextNode
// reads the next node record from the iterator, skipping over other
// database entries.
func nextNode(it iterator.Iterator) *Node {
for end := false; !end; end = !it.Next() {
id, field := splitKey(it.Key())
if field != nodeDBDiscoverRoot {
continue
}
var n Node
if err := rlp.DecodeBytes(it.Value(), &n); err != nil {
if glog.V(logger.Warn) {
glog.Errorf("invalid node %x: %v", id, err)
}
continue
}
return &n
}
return nil
}
示例6: safeQuery
// Make the actual query. Sanity checks of the iterator i is expected to
// have been done before calling this function.
func safeQuery(i iter.Iterator, req QueryRequest, res chan StoredEvent) {
defer close(res)
for i.Valid() {
curKey, err := newEventStoreKey(i.Key())
if err != nil {
log.Println("A key could not be deserialized:")
// Panicing here, because this error most
// certainly needs to be looked at by a
// an operator.
log.Panicln(string(i.Key()))
}
if bytes.Compare(curKey.groupKey, eventPrefix) != 0 {
break
}
if bytes.Compare(curKey.key, req.Stream) != 0 {
break
}
resEvent := StoredEvent{
curKey.keyId.toBytes(),
Event{
curKey.key,
[]byte(i.Value()),
},
}
res <- resEvent
keyId := curKey.keyId.toBytes()
if req.ToId != nil && bytes.Compare(req.ToId, keyId) == 0 {
break
}
i.Next()
}
}
示例7: next
func (h *blockHarness) next(pref string, iter iterator.Iterator) {
if !iter.Next() {
h.t.Fatalf("block: %sNext: eoi, err=%v", pref, iter.Error())
}
}
示例8: convertFrom
func convertFrom(c *cli.Context) {
success := true
defaultBand := c.GlobalString("band")
dbPath := c.GlobalString("path")
pwd, err := os.Getwd()
dbPath = path.Join(pwd, dbPath)
options := &opt.Options{ErrorIfMissing: true}
db, err := leveldb.OpenFile(dbPath, options)
if err != nil {
msg := fmt.Sprintf("%s %s", err, dbPath)
panic(msg)
}
fmt.Println("using database:", dbPath)
defer db.Close()
var iter iterator.Iterator
fmt.Println("Converting FROM band format...")
iter = db.NewIterator(&dbutil.Range{Start: []byte("/reading/RF12:"), Limit: []byte("/reading/RF12~")}, nil)
for iter.Next() {
key := string(iter.Key())
rval := iter.Value()
kparts := strings.Split(key, "/")
rfnet := kparts[len(kparts)-1:]
rfparts := strings.Split(rfnet[0], ":")
if len(rfparts) == 4 { //its an new format with band
if rfparts[1] == defaultBand {
fmt.Println("INFO:Downgrading:", key)
//remove band
copy(rfparts[1:], rfparts[1+1:])
rfparts[len(rfparts)-1] = ""
rfparts = rfparts[:len(rfparts)-1]
//adjust the json structure
var reading Reading
err := json.Unmarshal(rval, &reading)
if err == nil {
id := fmt.Sprintf("%s", strings.Join(rfparts, ":"))
reading.Id = id
fmt.Println("INFO:New reading:", reading)
data, err := json.Marshal(reading)
if err == nil {
//write a new key
newkey := "/reading/" + id
err = db.Put([]byte(newkey), []byte(data), nil)
if err != nil {
fmt.Println("ERR:Write failed for:", newkey)
success = false
continue
}
fmt.Println("INFO:New Reading Stored:", newkey)
//remove old key
err = db.Delete([]byte(key), nil)
if err != nil {
success = false
fmt.Println("WARN: could not remove old key:", key)
}
}
} else {
fmt.Println("Err:Failed to unmarshal data:", err)
success = false
}
}
}
}
iter.Release()
err = iter.Error()
if err != nil {
fmt.Println(err)
}
fmt.Println("Downgrade finished")
if !success {
fmt.Println("problems detected, please review screen")
}
}