4505382590
- Focus on header mode - Add context to errors, trace guard clauses, warn on non-returned errors - Give errors distinct names so compiler will recognize if unchecked - Remove redundant type declarations/fix typos
125 lines
4.3 KiB
Go
125 lines
4.3 KiB
Go
// VulcanizeDB
|
|
// Copyright © 2019 Vulcanize
|
|
|
|
// This program is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Affero General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
|
|
// This program is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Affero General Public License for more details.
|
|
|
|
// You should have received a copy of the GNU Affero General Public License
|
|
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
package fetcher
|
|
|
|
import (
|
|
"fmt"
|
|
"log"
|
|
"math/big"
|
|
|
|
"github.com/ethereum/go-ethereum/common"
|
|
|
|
"github.com/vulcanize/vulcanizedb/pkg/core"
|
|
)
|
|
|
|
// Fetcher serves as the lower level data fetcher that calls the underlying
|
|
// blockchain's FetchConctractData method for a given return type
|
|
|
|
// Interface definition for a Fetcher
|
|
type FetcherInterface interface {
|
|
FetchBigInt(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (big.Int, error)
|
|
FetchBool(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (bool, error)
|
|
FetchAddress(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (common.Address, error)
|
|
FetchString(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (string, error)
|
|
FetchHash(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (common.Hash, error)
|
|
}
|
|
|
|
// Used to create a new Fetcher error for a given error and fetch method
|
|
func newFetcherError(err error, fetchMethod string) *fetcherError {
|
|
e := fetcherError{err.Error(), fetchMethod}
|
|
log.Println(e.Error())
|
|
return &e
|
|
}
|
|
|
|
// Fetcher struct
|
|
type Fetcher struct {
|
|
BlockChain core.BlockChain // Underlying Blockchain
|
|
}
|
|
|
|
// Fetcher error
|
|
type fetcherError struct {
|
|
err string
|
|
fetchMethod string
|
|
}
|
|
|
|
// Fetcher error method
|
|
func (fe *fetcherError) Error() string {
|
|
return fmt.Sprintf("Error fetching %s: %s", fe.fetchMethod, fe.err)
|
|
}
|
|
|
|
// Generic Fetcher methods used by Getters to call contract methods
|
|
|
|
// Method used to fetch big.Int value from contract
|
|
func (f Fetcher) FetchBigInt(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (big.Int, error) {
|
|
var result = new(big.Int)
|
|
err := f.BlockChain.FetchContractData(contractAbi, contractAddress, method, methodArgs, &result, blockNumber)
|
|
|
|
if err != nil {
|
|
return *result, newFetcherError(err, method)
|
|
}
|
|
|
|
return *result, nil
|
|
}
|
|
|
|
// Method used to fetch bool value from contract
|
|
func (f Fetcher) FetchBool(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (bool, error) {
|
|
var result = new(bool)
|
|
err := f.BlockChain.FetchContractData(contractAbi, contractAddress, method, methodArgs, &result, blockNumber)
|
|
|
|
if err != nil {
|
|
return *result, newFetcherError(err, method)
|
|
}
|
|
|
|
return *result, nil
|
|
}
|
|
|
|
// Method used to fetch address value from contract
|
|
func (f Fetcher) FetchAddress(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (common.Address, error) {
|
|
var result = new(common.Address)
|
|
err := f.BlockChain.FetchContractData(contractAbi, contractAddress, method, methodArgs, &result, blockNumber)
|
|
|
|
if err != nil {
|
|
return *result, newFetcherError(err, method)
|
|
}
|
|
|
|
return *result, nil
|
|
}
|
|
|
|
// Method used to fetch string value from contract
|
|
func (f Fetcher) FetchString(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (string, error) {
|
|
var result = new(string)
|
|
err := f.BlockChain.FetchContractData(contractAbi, contractAddress, method, methodArgs, &result, blockNumber)
|
|
|
|
if err != nil {
|
|
return *result, newFetcherError(err, method)
|
|
}
|
|
|
|
return *result, nil
|
|
}
|
|
|
|
// Method used to fetch hash value from contract
|
|
func (f Fetcher) FetchHash(method, contractAbi, contractAddress string, blockNumber int64, methodArgs []interface{}) (common.Hash, error) {
|
|
var result = new(common.Hash)
|
|
err := f.BlockChain.FetchContractData(contractAbi, contractAddress, method, methodArgs, &result, blockNumber)
|
|
|
|
if err != nil {
|
|
return *result, newFetcherError(err, method)
|
|
}
|
|
|
|
return *result, nil
|
|
}
|