ipld-eth-server/pkg/transformers/shared/log_chunker.go
2018-12-07 18:10:36 +01:00

58 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 (
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
)
type LogChunker struct {
addressToNames map[string][]string
nameToTopic0 map[string]common.Hash
}
// Initialises a chunker by creating efficient lookup maps
func NewLogChunker(transformerConfigs []TransformerConfig) LogChunker {
addressToNames := map[string][]string{}
nameToTopic0 := map[string]common.Hash{}
for _, config := range transformerConfigs {
for _, address := range config.ContractAddresses {
addressToNames[address] = append(addressToNames[address], config.TransformerName)
nameToTopic0[config.TransformerName] = common.HexToHash(config.Topic)
}
}
return LogChunker{
addressToNames,
nameToTopic0,
}
}
// Goes through an array of logs, associating relevant logs with transformers
func (chunker LogChunker) ChunkLogs(logs []types.Log) (chunks map[string][]types.Log) {
for _, log := range logs {
// Topic0 is not unique to each transformer, also need to consider the contract address
relevantTransformers := chunker.addressToNames[log.Address.String()]
for _, transformer := range relevantTransformers {
if chunker.nameToTopic0[transformer] == log.Topics[0] {
chunks[transformer] = append(chunks[transformer], log)
}
}
}
return
}