store.go

/*
 * Copyright (C) 2018 The ontology Authors
 * This file is part of The ontology library.
 *
 * The ontology is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * The ontology is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with The ontology.  If not, see <http://www.gnu.org/licenses/>.
 */

package common

import (
	"errors"

	"github.com/ontio/layer2/node/common"
	"github.com/ontio/layer2/node/smartcontract/event"
)

var ErrNotFound = errors.New("not found")

//Store iterator for iterate store
type StoreIterator interface {
	Next() bool //Next item. If item available return true, otherwise return false
	//Prev() bool           //previous item. If item available return true, otherwise return false
	First() bool //First item. If item available return true, otherwise return false
	//Last() bool           //Last item. If item available return true, otherwise return false
	//Seek(key []byte) bool //Seek key. If item available return true, otherwise return false
	Key() []byte   //Return the current item key
	Value() []byte //Return the current item value
	Release()      //Close iterator
	Error() error  // Error returns any accumulated error.
}

//PersistStore of ledger
type PersistStore interface {
	Put(key []byte, value []byte) error      //Put the key-value pair to store
	Get(key []byte) ([]byte, error)          //Get the value if key in store
	Has(key []byte) (bool, error)            //Whether the key is exist in store
	Delete(key []byte) error                 //Delete the key in store
	NewBatch()                               //Start commit batch
	BatchPut(key []byte, value []byte)       //Put a key-value pair to batch
	BatchDelete(key []byte)                  //Delete the key in batch
	BatchCommit() error                      //Commit batch to store
	Close() error                            //Close store
	NewIterator(prefix []byte) StoreIterator //Return the iterator of store
}

//EventStore save event notify
type EventStore interface {
	//SaveEventNotifyByTx save event notify gen by smart contract execution
	SaveEventNotifyByTx(txHash common.Uint256, notify *event.ExecuteNotify) error
	//Save transaction hashes which have event notify gen
	SaveEventNotifyByBlock(height uint32, txHashs []common.Uint256)
	//GetEventNotifyByTx return event notify by transaction hash
	GetEventNotifyByTx(txHash common.Uint256) (*event.ExecuteNotify, error)
	//Commit event notify to store
	CommitTo() error
}