ipld-eth-server/pkg/transformers/cat_file/flip/converter.go
Rob Mulholand 58f17a24ae Add transformers for Cat file events
- transform logs from 3 implementations of file on the Cat contract
2018-09-27 10:32:08 -05:00

69 lines
1.9 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 flip
import (
"bytes"
"encoding/json"
"errors"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
)
type Converter interface {
ToModels(ethLogs []types.Log) ([]CatFileFlipModel, error)
}
type CatFileFlipConverter struct{}
func (CatFileFlipConverter) ToModels(ethLogs []types.Log) ([]CatFileFlipModel, error) {
var results []CatFileFlipModel
for _, ethLog := range ethLogs {
err := verifyLog(ethLog)
if err != nil {
return nil, err
}
ilk := string(bytes.Trim(ethLog.Topics[2].Bytes(), "\x00"))
what := string(bytes.Trim(ethLog.Topics[3].Bytes(), "\x00"))
flipBytes := ethLog.Data[len(ethLog.Data)-shared.DataItemLength:]
flip := common.BytesToAddress(flipBytes).String()
raw, err := json.Marshal(ethLog)
if err != nil {
return nil, err
}
result := CatFileFlipModel{
Ilk: ilk,
What: what,
Flip: flip,
TransactionIndex: ethLog.TxIndex,
Raw: raw,
}
results = append(results, result)
}
return results, nil
}
func verifyLog(log types.Log) error {
if len(log.Topics) < 4 {
return errors.New("log missing topics")
}
if len(log.Data) < shared.DataItemLength {
return errors.New("log missing data")
}
return nil
}