ipld-eth-server/pkg/geth/contract.go
Matt K 6decf0b54b Remove pubsub and replace w/ polling head of chain (#122)
* Rename geth package structs to not be prefaced with package name

* No longer need to dump schema since Travis uses migrate

* Rearrange history package

* Removed double request for receipt from block rewards

* Remove Listener + Observers and Replace w/ Polling Head

* Potential Short term Issue w/ Infura (ignore these tests for now)
2018-01-05 11:55:00 -06:00

59 lines
1.6 KiB
Go

package geth
import (
"errors"
"sort"
"context"
"math/big"
"github.com/8thlight/vulcanizedb/pkg/core"
"github.com/ethereum/go-ethereum"
"github.com/ethereum/go-ethereum/common"
)
var (
ErrInvalidStateAttribute = errors.New("invalid state attribute")
)
func (blockchain *Blockchain) GetAttribute(contract core.Contract, attributeName string, blockNumber *big.Int) (interface{}, error) {
parsed, err := ParseAbi(contract.Abi)
var result interface{}
if err != nil {
return result, err
}
input, err := parsed.Pack(attributeName)
if err != nil {
return nil, ErrInvalidStateAttribute
}
output, err := callContract(contract.Hash, input, blockchain, blockNumber)
if err != nil {
return nil, err
}
err = parsed.Unpack(&result, attributeName, output)
if err != nil {
return nil, err
}
return result, nil
}
func callContract(contractHash string, input []byte, blockchain *Blockchain, blockNumber *big.Int) ([]byte, error) {
to := common.HexToAddress(contractHash)
msg := ethereum.CallMsg{To: &to, Data: input}
return blockchain.client.CallContract(context.Background(), msg, blockNumber)
}
func (blockchain *Blockchain) GetAttributes(contract core.Contract) (core.ContractAttributes, error) {
parsed, _ := ParseAbi(contract.Abi)
var contractAttributes core.ContractAttributes
for _, abiElement := range parsed.Methods {
if (len(abiElement.Outputs) > 0) && (len(abiElement.Inputs) == 0) && abiElement.Const {
attributeType := abiElement.Outputs[0].Type.String()
contractAttributes = append(contractAttributes, core.ContractAttribute{abiElement.Name, attributeType})
}
}
sort.Sort(contractAttributes)
return contractAttributes, nil
}