ipld-eth-server/pkg/transformers/factories/transformer.go

105 lines
3.4 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 factories
import (
"github.com/ethereum/go-ethereum/core/types"
"github.com/vulcanize/vulcanizedb/pkg/datastore/postgres"
"log"
"github.com/ethereum/go-ethereum/common"
"github.com/vulcanize/vulcanizedb/pkg/core"
"github.com/vulcanize/vulcanizedb/pkg/transformers/shared"
)
type Transformer struct {
Config shared.SingleTransformerConfig
Converter Converter
Repository Repository
Fetcher shared.SettableLogFetcher
}
type Converter interface {
ToModels(ethLog []types.Log) ([]interface{}, error)
}
type Repository interface {
Create(headerID int64, models []interface{}) error
MarkHeaderChecked(headerID int64) error
MissingHeaders(startingBlockNumber, endingBlockNumber int64) ([]core.Header, error)
SetDB(db *postgres.DB)
}
func (transformer Transformer) NewTransformer(db *postgres.DB, bc core.BlockChain) shared.Transformer {
transformer.Repository.SetDB(db)
transformer.Fetcher.SetBC(bc)
return transformer
}
func (transformer Transformer) Execute() error {
transformerName := transformer.Config.TransformerName
missingHeaders, err := transformer.Repository.MissingHeaders(transformer.Config.StartingBlockNumber, transformer.Config.EndingBlockNumber)
if err != nil {
log.Printf("Error fetching mising headers in %v transformer: %v \n", transformerName, err)
return err
}
// Grab event signature from transformer config
// (Double-array structure required for go-ethereum FilterQuery)
var topic = [][]common.Hash{{common.HexToHash(transformer.Config.Topic)}}
log.Printf("Fetching %v event logs for %d headers \n", transformerName, len(missingHeaders))
for _, header := range missingHeaders {
// Fetch the missing logs for a given header
matchingLogs, err := transformer.Fetcher.FetchLogs(transformer.Config.ContractAddresses, topic, header.BlockNumber)
if err != nil {
log.Printf("Error fetching matching logs in %v transformer: %v", transformerName, err)
return err
}
// No matching logs, mark the header as checked for this type of logs
if len(matchingLogs) < 1 {
err := transformer.Repository.MarkHeaderChecked(header.Id)
if err != nil {
log.Printf("Error marking header as checked in %v: %v", transformerName, err)
return err
}
// Continue with the next header; nothing to persist
continue
}
models, err := transformer.Converter.ToModels(matchingLogs)
if err != nil {
log.Printf("Error converting logs in %v: %v", transformerName, err)
return err
}
// Can't assert a whole collection, wash types individually for Create,
// which needs interface{}
var typelessModels []interface{}
for _, m := range models {
typelessModels = append(typelessModels, m.(interface{}))
}
err = transformer.Repository.Create(header.Id, typelessModels)
if err != nil {
log.Printf("Error persisting %v record: %v", transformerName, err)
return err
}
}
return nil
}