Golang Database.NewBatch方法代碼示例

// PutTransactions stores the transactions in the given database
func PutTransactions(db ethdb.Database, block *types.Block, txs types.Transactions) error {
	batch := db.NewBatch()

	for i, tx := range block.Transactions() {
		rlpEnc, err := rlp.EncodeToBytes(tx)
		if err != nil {
			return fmt.Errorf("failed encoding tx: %v", err)
		}

		batch.Put(tx.Hash().Bytes(), rlpEnc)

		var txExtra struct {
			BlockHash  common.Hash
			BlockIndex uint64
			Index      uint64
		}
		txExtra.BlockHash = block.Hash()
		txExtra.BlockIndex = block.NumberU64()
		txExtra.Index = uint64(i)
		rlpMeta, err := rlp.EncodeToBytes(txExtra)
		if err != nil {
			return fmt.Errorf("failed encoding tx meta data: %v", err)
		}

		batch.Put(append(tx.Hash().Bytes(), 0x0001), rlpMeta)
	}

	if err := batch.Write(); err != nil {
		return fmt.Errorf("failed writing tx to db: %v", err)
	}
	return nil
}

// WriteMapmapBloom writes each address included in the receipts' logs to the
// MIP bloom bin.
func WriteMipmapBloom(db ethdb.Database, number uint64, receipts types.Receipts) error {
	batch := db.NewBatch()
	for _, level := range MIPMapLevels {
		key := mipmapKey(number, level)
		bloomDat, _ := db.Get(key)
		bloom := types.BytesToBloom(bloomDat)
		for _, receipt := range receipts {
			for _, log := range receipt.Logs {
				bloom.Add(log.Address.Big())
			}
		}
		batch.Put(key, bloom.Bytes())
	}
	if err := batch.Write(); err != nil {
		return fmt.Errorf("mipmap write fail for: %d: %v", number, err)
	}
	return nil
}

// WriteReceipts stores a batch of transaction receipts into the database.
func WriteReceipts(db ethdb.Database, receipts types.Receipts) error {
	batch := db.NewBatch()

	// Iterate over all the receipts and queue them for database injection
	for _, receipt := range receipts {
		storageReceipt := (*types.ReceiptForStorage)(receipt)
		data, err := rlp.EncodeToBytes(storageReceipt)
		if err != nil {
			return err
		}
		if err := batch.Put(append(receiptsPrefix, receipt.TxHash.Bytes()...), data); err != nil {
			return err
		}
	}
	// Write the scheduled data into the database
	if err := batch.Write(); err != nil {
		glog.Fatalf("failed to store receipts into database: %v", err)
		return err
	}
	return nil
}

// WriteTransactions stores the transactions associated with a specific block
// into the given database. Beside writing the transaction, the function also
// stores a metadata entry along with the transaction, detailing the position
// of this within the blockchain.
func WriteTransactions(db ethdb.Database, block *types.Block) error {
	batch := db.NewBatch()

	// Iterate over each transaction and encode it with its metadata
	for i, tx := range block.Transactions() {
		// Encode and queue up the transaction for storage
		data, err := rlp.EncodeToBytes(tx)
		if err != nil {
			return err
		}
		if err := batch.Put(tx.Hash().Bytes(), data); err != nil {
			return err
		}
		// Encode and queue up the transaction metadata for storage
		meta := struct {
			BlockHash  common.Hash
			BlockIndex uint64
			Index      uint64
		}{
			BlockHash:  block.Hash(),
			BlockIndex: block.NumberU64(),
			Index:      uint64(i),
		}
		data, err = rlp.EncodeToBytes(meta)
		if err != nil {
			return err
		}
		if err := batch.Put(append(tx.Hash().Bytes(), txMetaSuffix...), data); err != nil {
			return err
		}
	}
	// Write the scheduled data into the database
	if err := batch.Write(); err != nil {
		glog.Fatalf("failed to store transactions into database: %v", err)
		return err
	}
	return nil
}