ipld-eth-server/pkg/geth/contract.go
2017-12-04 10:34:49 -06:00

68 lines
2.2 KiB
Go

package geth
import (
"errors"
"fmt"
"path/filepath"
"sort"
"github.com/8thlight/vulcanizedb/pkg/config"
"github.com/8thlight/vulcanizedb/pkg/core"
"github.com/ethereum/go-ethereum/accounts/abi/bind"
"github.com/ethereum/go-ethereum/common"
)
var (
ErrInvalidStateAttribute = errors.New("invalid state attribute")
)
func (blockchain *GethBlockchain) GetContract(contractHash string) (core.Contract, error) {
attributes, err := blockchain.getContractAttributes(contractHash)
if err != nil {
return core.Contract{}, err
} else {
contract := core.Contract{
Attributes: attributes,
Hash: contractHash,
}
return contract, nil
}
}
func (blockchain *GethBlockchain) GetAttribute(contract core.Contract, attributeName string) (interface{}, error) {
boundContract, err := bindContract(common.HexToAddress(contract.Hash), blockchain.client, blockchain.client)
if err != nil {
return nil, err
}
var result interface{}
err = boundContract.Call(&bind.CallOpts{}, &result, attributeName)
if err != nil {
return nil, ErrInvalidStateAttribute
}
return result, nil
}
func (blockchain *GethBlockchain) getContractAttributes(contractHash string) (core.ContractAttributes, error) {
abiFilePath := filepath.Join(config.ProjectRoot(), "contracts", "public", fmt.Sprintf("%s.json", contractHash))
parsed, _ := ParseAbiFile(abiFilePath)
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
}
func bindContract(address common.Address, caller bind.ContractCaller, transactor bind.ContractTransactor) (bind.BoundContract, error) {
abiFilePath := filepath.Join(config.ProjectRoot(), "contracts", "public", fmt.Sprintf("%s.json", address.Hex()))
parsed, err := ParseAbiFile(abiFilePath)
if err != nil {
return bind.BoundContract{}, err
}
return *bind.NewBoundContract(address, parsed, caller, transactor), nil
}