github.com/cuiweixie/go-ethereum@v1.8.2-0.20180303084001-66cd41af1e38/ethdb/interface.go (about)

     1  // Copyright 2014 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package ethdb
    18  
    19  // Code using batches should try to add this much data to the batch.
    20  // The value was determined empirically.
    21  const IdealBatchSize = 100 * 1024
    22  
    23  // Putter wraps the database write operation supported by both batches and regular databases.
    24  type Putter interface {
    25  	Put(key []byte, value []byte) error
    26  }
    27  
    28  // Database wraps all database operations. All methods are safe for concurrent use.
    29  type Database interface {
    30  	Putter
    31  	Get(key []byte) ([]byte, error)
    32  	Has(key []byte) (bool, error)
    33  	Delete(key []byte) error
    34  	Close()
    35  	NewBatch() Batch
    36  }
    37  
    38  // Batch is a write-only database that commits changes to its host database
    39  // when Write is called. Batch cannot be used concurrently.
    40  type Batch interface {
    41  	Putter
    42  	ValueSize() int // amount of data in the batch
    43  	Write() error
    44  	// Reset resets the batch for reuse
    45  	Reset()
    46  }