ipld-eth-server/pkg/transformers/shared/log_fetcher.go
2018-10-23 10:43:03 +02:00

71 lines
1.8 KiB
Go

// Copyright 2018 Vulcanize
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package shared
import (
"math/big"
"github.com/ethereum/go-ethereum"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/vulcanize/vulcanizedb/pkg/core"
)
type LogFetcher interface {
FetchLogs(contractAddresses []string, topics [][]common.Hash, blockNumber int64) ([]types.Log, error)
}
type SettableLogFetcher interface {
LogFetcher
SetBC(bc core.BlockChain)
}
type Fetcher struct {
blockChain core.BlockChain
}
func (fetcher *Fetcher) SetBC(bc core.BlockChain) {
fetcher.blockChain = bc
}
func NewFetcher(blockchain core.BlockChain) Fetcher {
return Fetcher{
blockChain: blockchain,
}
}
func (fetcher Fetcher) FetchLogs(contractAddresses []string, topics [][]common.Hash, blockNumber int64) ([]types.Log, error) {
block := big.NewInt(blockNumber)
addresses := hexStringsToAddresses(contractAddresses)
query := ethereum.FilterQuery{
FromBlock: block,
ToBlock: block,
Addresses: addresses,
Topics: topics,
}
return fetcher.blockChain.GetEthLogsWithCustomQuery(query)
}
func hexStringsToAddresses(hexStrings []string) []common.Address {
var addresses []common.Address
for _, hexString := range hexStrings {
address := common.HexToAddress(hexString)
addresses = append(addresses, address)
}
return addresses
}