ipld-eth-server/pkg/transformers/shared/log_chunker.go
2019-01-16 14:24:00 -06:00

68 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 shared
import (
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/types"
"strings"
)
type Chunker interface {
AddConfigs(transformerConfigs []TransformerConfig)
ChunkLogs(logs []types.Log) map[string][]types.Log
}
type LogChunker struct {
AddressToNames map[string][]string
NameToTopic0 map[string]common.Hash
}
// Returns a new log chunker with initialised maps.
// Needs to have configs added with `AddConfigs` to consider logs for the respective transformer.
func NewLogChunker() *LogChunker {
return &LogChunker{
AddressToNames: map[string][]string{},
NameToTopic0: map[string]common.Hash{},
}
}
// Configures the chunker by adding more addreses and topics to consider.
func (chunker *LogChunker) AddConfigs(transformerConfigs []TransformerConfig) {
for _, config := range transformerConfigs {
for _, address := range config.ContractAddresses {
var lowerCaseAddress = strings.ToLower(address)
chunker.AddressToNames[lowerCaseAddress] = append(chunker.AddressToNames[lowerCaseAddress], config.TransformerName)
chunker.NameToTopic0[config.TransformerName] = common.HexToHash(config.Topic)
}
}
}
// Goes through an array of logs, associating relevant logs (matching addresses and topic) with transformers
func (chunker *LogChunker) ChunkLogs(logs []types.Log) map[string][]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[strings.ToLower(log.Address.String())]
for _, transformer := range relevantTransformers {
if chunker.NameToTopic0[transformer] == log.Topics[0] {
chunks[transformer] = append(chunks[transformer], log)
}
}
}
return chunks
}