Golang Tx.Bucket方法代码示例

// applyFileContractMaintenance looks for all of the file contracts that have
// expired without an appropriate storage proof, and calls 'applyMissedProof'
// for the file contract.
func applyFileContractMaintenance(tx *bolt.Tx, pb *processedBlock) {
	// Get the bucket pointing to all of the expiring file contracts.
	fceBucketID := append(prefixFCEX, encoding.Marshal(pb.Height)...)
	fceBucket := tx.Bucket(fceBucketID)
	// Finish if there are no expiring file contracts.
	if fceBucket == nil {
		return
	}

	var dscods []modules.DelayedSiacoinOutputDiff
	var fcds []modules.FileContractDiff
	err := fceBucket.ForEach(func(keyBytes, valBytes []byte) error {
		var id types.FileContractID
		copy(id[:], keyBytes)
		amspDSCODS, fcd := applyMissedStorageProof(tx, pb, id)
		fcds = append(fcds, fcd)
		dscods = append(dscods, amspDSCODS...)
		return nil
	})
	if build.DEBUG && err != nil {
		panic(err)
	}
	for _, dscod := range dscods {
		pb.DelayedSiacoinOutputDiffs = append(pb.DelayedSiacoinOutputDiffs, dscod)
		commitDelayedSiacoinOutputDiff(tx, dscod, modules.DiffApply)
	}
	for _, fcd := range fcds {
		pb.FileContractDiffs = append(pb.FileContractDiffs, fcd)
		commitFileContractDiff(tx, fcd, modules.DiffApply)
	}
	err = tx.DeleteBucket(fceBucketID)
	if build.DEBUG && err != nil {
		panic(err)
	}
}

// Retrieves a key from the database and verifies that it is what is expected.
func simulateGetHandler(tx *bolt.Tx, qdb *QuickDB) {
	// Randomly retrieve an existing exist.
	keys := qdb.Rand()
	if len(keys) == 0 {
		return
	}

	// Retrieve root bucket.
	b := tx.Bucket(keys[0])
	if b == nil {
		panic(fmt.Sprintf("bucket[0] expected: %08x\n", trunc(keys[0], 4)))
	}

	// Drill into nested buckets.
	for _, key := range keys[1 : len(keys)-1] {
		b = b.Bucket(key)
		if b == nil {
			panic(fmt.Sprintf("bucket[n] expected: %v -> %v\n", keys, key))
		}
	}

	// Verify key/value on the final bucket.
	expected := qdb.Get(keys)
	actual := b.Get(keys[len(keys)-1])
	if !bytes.Equal(actual, expected) {
		fmt.Println("=== EXPECTED ===")
		fmt.Println(expected)
		fmt.Println("=== ACTUAL ===")
		fmt.Println(actual)
		fmt.Println("=== END ===")
		panic("value mismatch")
	}
}

//Del deletes one key-value pair.
func Del(tx *bolt.Tx, bucket string, key []byte) error {
	b := tx.Bucket([]byte(bucket))
	if b == nil {
		return errors.New("bucket not found " + bucket)
	}
	return b.Delete(key)
}

func EntrySave(tx *bolt.Tx, entry DbEntry, key string) error {
	godbc.Require(tx != nil)
	godbc.Require(len(key) > 0)

	// Access bucket
	b := tx.Bucket([]byte(entry.BucketName()))
	if b == nil {
		err := errors.New("Unable to access db")
		logger.Err(err)
		return err
	}

	// Save device entry to db
	buffer, err := entry.Marshal()
	if err != nil {
		logger.Err(err)
		return err
	}

	// Save data using the id as the key
	err = b.Put([]byte(key), buffer)
	if err != nil {
		logger.Err(err)
		return err
	}

	return nil
}

// saveRepository saves a repository in the store.
func (s *Store) saveRepository(tx *bolt.Tx, r *internal.Repository) error {
	buf, err := proto.Marshal(r)
	if err != nil {
		return err
	}
	return tx.Bucket([]byte("repositories")).Put([]byte(r.GetID()), buf)
}

// addBlockMap adds a processed block to the block map.
func addBlockMap(tx *bolt.Tx, pb *processedBlock) {
	id := pb.Block.ID()
	err := tx.Bucket(BlockMap).Put(id[:], encoding.Marshal(*pb))
	if build.DEBUG && err != nil {
		panic(err)
	}
}

// removeFileContract removes a file contract from the database.
func removeFileContract(tx *bolt.Tx, id types.FileContractID) {
	// Delete the file contract entry.
	fcBucket := tx.Bucket(FileContracts)
	fcBytes := fcBucket.Get(id[:])
	// Sanity check - should not be removing a file contract not in the db.
	if build.DEBUG && fcBytes == nil {
		panic("nil file contract")
	}
	err := fcBucket.Delete(id[:])
	if build.DEBUG && err != nil {
		panic(err)
	}

	// Delete the entry for the file contract's expiration. The portion of
	// 'fcBytes' used to determine the expiration bucket id is the
	// byte-representation of the file contract window end, which always
	// appears at bytes 48-56.
	expirationBucketID := append(prefixFCEX, fcBytes[48:56]...)
	expirationBucket := tx.Bucket(expirationBucketID)
	expirationBytes := expirationBucket.Get(id[:])
	if expirationBytes == nil {
		panic(errNilItem)
	}
	err = expirationBucket.Delete(id[:])
	if build.DEBUG && err != nil {
		panic(err)
	}
}

// validSiacoins checks that the siacoin inputs and outputs are valid in the
// context of the current consensus set.
func validSiacoins(tx *bolt.Tx, t types.Transaction) error {
	scoBucket := tx.Bucket(SiacoinOutputs)
	var inputSum types.Currency
	for _, sci := range t.SiacoinInputs {
		// Check that the input spends an existing output.
		scoBytes := scoBucket.Get(sci.ParentID[:])
		if scoBytes == nil {
			return errMissingSiacoinOutput
		}

		// Check that the unlock conditions match the required unlock hash.
		var sco types.SiacoinOutput
		err := encoding.Unmarshal(scoBytes, &sco)
		if build.DEBUG && err != nil {
			panic(err)
		}
		if sci.UnlockConditions.UnlockHash() != sco.UnlockHash {
			return errWrongUnlockConditions
		}

		inputSum = inputSum.Add(sco.Value)
	}
	if inputSum.Cmp(t.SiacoinOutputSum()) != 0 {
		return errSiacoinInputOutputMismatch
	}
	return nil
}

func (db *DB) addTerm(tx *bolt.Tx, term rdf.Term) (id uint32, err error) {
	bt := db.encode(term)

	if id, err = db.getIDb(tx, bt); err == nil {
		// Term is allready in database
		return id, nil
	} else if err != ErrNotFound {
		// Some other IO error occured
		return 0, err
	}

	// get a new ID
	bkt := tx.Bucket(bucketTerms)
	n, err := bkt.NextSequence()
	if err != nil {
		return 0, err
	}
	if n > MaxTerms {
		return 0, ErrDBFull
	}

	id = uint32(n)
	idb := u32tob(uint32(n))

	// store term and index it
	err = bkt.Put(idb, bt)
	if err != nil {
		return 0, err
	}
	bkt = tx.Bucket(bucketIdxTerms)
	err = bkt.Put(bt, idb)
	return id, err
}

func bucketOrPanic(tx *bolt.Tx, name []byte) *bolt.Bucket {
	b := tx.Bucket(name)
	if b == nil {
		panic("Missing bucket")
	}
	return b
}

// Add a single sentence to the database
func (ns *Nonsentence) addSentence(tx *bolt.Tx, sentence string) error {
	wordsBucket := tx.Bucket([]byte("words"))
	startsBucket := tx.Bucket([]byte("starts"))
	if (wordsBucket == nil) || (startsBucket == nil) {
		return fmt.Errorf("Buckets not found")
	}

	// Split sentence on whitespace
	var words = strings.Fields(sentence)

	if len(words) < 3 {
		// 		log.Printf("Ignoring small sentence: %v", sentence)
		return nil
	}

	// Store words in wordsBucket
	for i := 2; i < len(words); i++ {
		if err := storeWords(wordsBucket, words[i-2], words[i-1], words[i]); err != nil {
			return err
		}
	}
	if err := storeWords(wordsBucket, words[len(words)-2], words[len(words)-1], ""); err != nil {
		return err
	}

	// Store starts in startsBucket
	key := []byte(words[0] + " " + words[1])
	if err := startsBucket.Put(key, []byte{}); err != nil {
		return err
	}

	return nil
}

// setSiafundPool updates the saved siafund pool on disk
func setSiafundPool(tx *bolt.Tx, c types.Currency) {
	bucket := tx.Bucket(SiafundPool)
	err := bucket.Put(SiafundPool, encoding.Marshal(c))
	if build.DEBUG && err != nil {
		panic(err)
	}
}

func addSiacoinOutput(tx *bolt.Tx, id types.SiacoinOutputID, sco types.SiacoinOutput) error {
	siacoinOutputs := tx.Bucket(SiacoinOutputs)
	if build.DEBUG && siacoinOutputs.Get(id[:]) != nil {
		panic(errRepeatInsert)
	}
	return siacoinOutputs.Put(id[:], encoding.Marshal(sco))
}

// forEach iterates through a bucket, calling the supplied closure on each
// element.
func forEach(tx *bolt.Tx, bucket []byte, fn func(k, v []byte) error) error {
	b := tx.Bucket(bucket)
	if build.DEBUG && b == nil {
		panic(errNilBucket)
	}
	return b.ForEach(fn)
}

func (qs *QuadStore) UpdateValueKeyBy(name string, amount int64, tx *bolt.Tx) error {
	value := ValueData{name, amount}
	b := tx.Bucket(nodeBucket)
	b.FillPercent = localFillPercent
	key := qs.createValueKeyFor(name)
	data := b.Get(key)

	if data != nil {
		// Node exists in the database -- unmarshal and update.
		err := json.Unmarshal(data, &value)
		if err != nil {
			glog.Errorf("Error: couldn't reconstruct value: %v", err)
			return err
		}
		value.Size += amount
	}

	// Are we deleting something?
	if value.Size <= 0 {
		value.Size = 0
	}

	// Repackage and rewrite.
	bytes, err := json.Marshal(&value)
	if err != nil {
		glog.Errorf("Couldn't write to buffer for value %s: %s", name, err)
		return err
	}
	err = b.Put(key, bytes)
	return err
}