ipld-eth-server/pkg/transformers/dent/converter.go
2018-10-22 12:14:43 -05:00

94 lines
2.3 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 dent
import (
"encoding/json"
"errors"
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
)
type Converter interface {
ToModels(ethLogs []types.Log) ([]DentModel, error)
}
type DentConverter struct{}
func NewDentConverter() DentConverter {
return DentConverter{}
}
func (c DentConverter) ToModels(ethLogs []types.Log) (result []DentModel, err error) {
for _, log := range ethLogs {
err := validateLog(log)
if err != nil {
return nil, err
}
bidId := log.Topics[2].Big()
lot := log.Topics[3].Big().String()
bidValue := getBidValue(log)
guy := common.HexToAddress(log.Topics[1].Hex()).String()
tic := "0"
//TODO: it is likely that the tic value will need to be added to an emitted event,
//so this will need to be updated at that point
logIndex := log.Index
transactionIndex := log.TxIndex
raw, err := json.Marshal(log)
if err != nil {
return nil, err
}
model := DentModel{
BidId: bidId.String(),
Lot: lot,
Bid: bidValue,
Guy: guy,
Tic: tic,
LogIndex: logIndex,
TransactionIndex: transactionIndex,
Raw: raw,
}
result = append(result, model)
}
return result, err
}
func validateLog(ethLog types.Log) error {
if len(ethLog.Data) <= 0 {
return errors.New("dent log data is empty")
}
if len(ethLog.Topics) < 4 {
return errors.New("dent log does not contain expected topics")
}
return nil
}
func getBidValue(ethLog types.Log) string {
itemByteLength := 32
lastDataItemStartIndex := len(ethLog.Data) - itemByteLength
lastItem := ethLog.Data[lastDataItemStartIndex:]
lastValue := big.NewInt(0).SetBytes(lastItem)
return lastValue.String()
}