Golang Bucket.Get方法代码示例

func getEncodedObject(bucket *bolt.Bucket, key string, value interface{}) error {
	data := bucket.Get([]byte(key))
	if data == nil {
		return ObjectNotFoundErr
	}
	return json.Unmarshal(data, &value)
}

// targetAdjustmentBase returns the magnitude that the target should be
// adjusted by before a clamp is applied.
func (cs *ConsensusSet) targetAdjustmentBase(blockMap *bolt.Bucket, pb *processedBlock) *big.Rat {
	// Grab the block that was generated 'TargetWindow' blocks prior to the
	// parent. If there are not 'TargetWindow' blocks yet, stop at the genesis
	// block.
	var windowSize types.BlockHeight
	parent := pb.Block.ParentID
	current := pb.Block.ID()
	for windowSize = 0; windowSize < types.TargetWindow && parent != (types.BlockID{}); windowSize++ {
		current = parent
		copy(parent[:], blockMap.Get(parent[:])[:32])
	}
	timestamp := types.Timestamp(encoding.DecUint64(blockMap.Get(current[:])[40:48]))

	// The target of a child is determined by the amount of time that has
	// passed between the generation of its immediate parent and its
	// TargetWindow'th parent. The expected amount of seconds to have passed is
	// TargetWindow*BlockFrequency. The target is adjusted in proportion to how
	// time has passed vs. the expected amount of time to have passed.
	//
	// The target is converted to a big.Rat to provide infinite precision
	// during the calculation. The big.Rat is just the int representation of a
	// target.
	timePassed := pb.Block.Timestamp - timestamp
	expectedTimePassed := types.BlockFrequency * windowSize
	return big.NewRat(int64(timePassed), int64(expectedTimePassed))
}

// Params returns the currently stored configuration parameters for hook h
// from bucket b.
func (RateLimitFilter) Params(h Hook, b *bolt.Bucket) map[string]string {
	m := make(map[string]string)
	for _, k := range []string{"amount", "interval"} {
		m[k] = string(b.Get([]byte(fmt.Sprintf("%s-%s", h.ID, k))))
	}
	return m
}

func addCityToIndex(
	bucket *bolt.Bucket, id string, name string, locale string, population uint32,
) error {
	var err error
	var cityName *ds.CityName

	if locale == "" {
		locale = "en"
	}

	cityNameKey := []byte(ds.PrepareCityNameKey(name))
	if conflict := bucket.Get(cityNameKey); conflict != nil {
		cityName, err = ds.CityNameFromString(string(cityNameKey), string(conflict))
		if strconv.Itoa(cityName.CityId) != id {
			cityNameKey = []byte(string(cityNameKey) + "|" + id)
		}
	}

	err = bucket.Put(
		cityNameKey, []byte(
			name+"\t"+id+"\t"+locale+"\t"+strconv.Itoa(int(population)),
		),
	)

	return err
}

// Params returns the currently stored configuration parameters for hook h
// from bucket b.
func (ForwardRequestAction) Params(h Hook, b *bolt.Bucket) map[string]string {
	m := make(map[string]string)
	for _, k := range []string{"url"} {
		m[k] = string(b.Get([]byte(fmt.Sprintf("%s-%s", h.ID, k))))
	}
	return m
}

// earliestChildTimestamp returns the earliest timestamp that a child node
// can have while still being valid. See section 'Timestamp Rules' in
// Consensus.md.
//
// To boost performance, earliestChildTimestamp is passed a bucket that it can
// use from inside of a boltdb transaction.
func earliestChildTimestamp(blockMap *bolt.Bucket, pb *processedBlock) types.Timestamp {
	// Get the previous MedianTimestampWindow timestamps.
	windowTimes := make(types.TimestampSlice, types.MedianTimestampWindow)
	windowTimes[0] = pb.Block.Timestamp
	parent := pb.Parent
	for i := uint64(1); i < types.MedianTimestampWindow; i++ {
		// If the genesis block is 'parent', use the genesis block timestamp
		// for all remaining times.
		if parent == (types.BlockID{}) {
			windowTimes[i] = windowTimes[i-1]
			continue
		}

		// Get the next parent's bytes. Because the ordering is specific, the
		// parent does not need to be decoded entirely to get the desired
		// information. This provides a performance boost. The id of the next
		// parent lies at the first 32 bytes, and the timestamp of the block
		// lies at bytes 40-48.
		parentBytes := blockMap.Get(parent[:])
		copy(parent[:], parentBytes[:32])
		windowTimes[i] = types.Timestamp(encoding.DecUint64(parentBytes[40:48]))
	}
	sort.Sort(windowTimes)

	// Return the median of the sorted timestamps.
	return windowTimes[len(windowTimes)/2]
}

// Params returns the currently stored configuration parameters for hook h
// from bucket b.
func (ExecuteAction) Params(h Hook, b *bolt.Bucket) map[string]string {
	m := make(map[string]string)
	for _, k := range []string{"command"} {
		m[k] = string(b.Get([]byte(fmt.Sprintf("%s-%s", h.ID, k))))
	}
	return m
}

// Params returns the currently stored configuration parameters for hook h
// from bucket b.
func (EmailAction) Params(h Hook, b *bolt.Bucket) map[string]string {
	m := make(map[string]string)
	for _, k := range []string{"token", "domain", "address", "subject", "template"} {
		m[k] = string(b.Get([]byte(fmt.Sprintf("%s-%s", h.ID, k))))
	}
	return m
}

func getGrantScopes(bucket *bolt.Bucket, grant string) map[string]bool {
	scopesByte := bucket.Get([]byte(grant))
	if scopesByte == nil {
		return nil
	}
	return database.StringToSet(string(scopesByte))
}

func (store *BoltStore) size(bucket *bolt.Bucket, key string, size *AtomicInt64) int64 {
	var statics *AtomicInt64 = size
	if statics == nil {
		statics = NewAtomicInt64(0)
	}

	if key != "" {
		b := bucket.Get([]byte(key))
		if b != nil {
			return statics.Caculate(int64(len(key) + len(b)))
		}

		bucket = bucket.Bucket([]byte(key))
	}

	if bucket != nil {
		c := bucket.Cursor()
		// to do staticsing
		for k, v := c.First(); k != nil; k, v = c.Next() {
			if v != nil {
				statics.Caculate(int64(len(k) + len(v)))
			} else {
				store.size(bucket, string(k), statics)
			}
		}
		statics.Caculate(int64(len(key)))
		return statics.Value()
	}

	//! null
	return statics.Value()
}

func (store *BoltStore) get(bucket *bolt.Bucket, key string, nested bool) (interface{}, error) {
	if key != "" {
		b := bucket.Get([]byte(key))
		if b != nil {
			return store.coder.Decode(b)
		}
		bucket = bucket.Bucket([]byte(key))
	}

	if bucket != nil {
		m := make(map[string]interface{})
		c := bucket.Cursor()
		for k, v := c.First(); k != nil; k, v = c.Next() {
			if v != nil {
				vv, err := store.coder.Decode(v)
				if err != nil {
					return nil, err
				}
				m[string(k)] = vv
			}

			if v == nil && nested == true {
				vv, err := store.get(bucket, string(k), nested)
				if err != nil {
					return nil, err
				}
				m[string(k)] = vv
			}
		}
		return m, nil
	}

	return nil, fmt.Errorf("bucket not exist")
}

// Store a word,word -> word sequence
func storeWords(bucket *bolt.Bucket, word1, word2, word3 string) error {
	key := []byte(word1 + " " + word2)

	// Get value from bucket and decode it
	rawValue := bucket.Get(key)
	var value []string
	if rawValue == nil {
		value = make([]string, 0, 1)
	} else {
		if err := json.Unmarshal(rawValue, &value); err != nil {
			log.Printf("Cannot decode raw value for key '%v': %v; starting new empty key; old value is: %v", string(key), string(rawValue))
			value = make([]string, 0, 1)
		}
	}

	// Add new word to value
	value = append(value, word3)

	// Encode value and store it in bucket
	rawValue, err := json.Marshal(value)
	if err != nil {
		return err
	}

	if err := bucket.Put(key, rawValue); err != nil {
		return err
	}

	// All done
	return nil
}

func (this *DB) getData(bucket *bolt.Bucket) (map[string]int, ipQueue, error) {
	var addrQ ipQueue
	heapRaw := bucket.Get(boltAddrHeapKey)
	if heapRaw == nil {
		addrQ = ipQueue(make([]*ipEntry, 0, 1))
	} else {
		dec := gob.NewDecoder(bytes.NewReader(heapRaw))
		if err := dec.Decode(&addrQ); err != nil {
			return nil, nil, err
		}
	}

	var addrMap map[string]int
	mapRaw := bucket.Get(boltAddrMapKey)
	if mapRaw == nil {
		addrMap = make(map[string]int)
	} else {
		dec := gob.NewDecoder(bytes.NewReader(mapRaw))
		if err := dec.Decode(&addrMap); err != nil {
			return nil, nil, err
		}
	}

	return addrMap, addrQ, nil
}

// Params returns the currently stored configuration parameters for hook h
// from bucket b.
func (GithubValidator) Params(h Hook, b *bolt.Bucket) map[string]string {
	m := make(map[string]string)
	for _, k := range []string{"secret"} {
		m[k] = string(b.Get([]byte(fmt.Sprintf("%s-%s", h.ID, k))))
	}
	return m
}

func fetchChanCommitKeys(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {

	// Construct the key which stores the commitment keys: ckk || channelID.
	// TODO(roasbeef): factor into func
	var bc bytes.Buffer
	if err := writeOutpoint(&bc, channel.ChanID); err != nil {
		return err
	}
	commitKey := make([]byte, len(commitKeys)+bc.Len())
	copy(commitKey[:3], commitKeys)
	copy(commitKey[3:], bc.Bytes())

	var err error
	keyBytes := nodeChanBucket.Get(commitKey)

	channel.TheirCommitKey, err = btcec.ParsePubKey(keyBytes[:33], btcec.S256())
	if err != nil {
		return err
	}

	channel.OurCommitKey, err = btcec.ParsePubKey(keyBytes[33:], btcec.S256())
	if err != nil {
		return err
	}

	return nil
}