core: vm: refactor governance and add node info oracle (#174)

1 files changed, 88 insertions, 0 deletions

diff --git a/core/vm/oracle.go b/core/vm/oracle.go
new file mode 100644
index 000000000..493736e8c
--- /dev/null
+++ b/core/vm/oracle.go
@@ -0,0 +1,88 @@
+// Copyright 2019 The dexon-consensus Authors
+// This file is part of the dexon-consensus library.
+//
+// The dexon-consensus library is free software: you can redistribute it
+// and/or modify it under the terms of the GNU Lesser General Public License as
+// published by the Free Software Foundation, either version 3 of the License,
+// or (at your option) any later version.
+//
+// The dexon-consensus library 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 Lesser
+// General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the dexon-consensus library. If not, see
+// <http://www.gnu.org/licenses/>.
+
+package vm
+
+import (
+	"strings"
+
+	"github.com/dexon-foundation/dexon/accounts/abi"
+	"github.com/dexon-foundation/dexon/common"
+)
+
+var GovernanceContractAddress = common.HexToAddress("63751838d6485578b23e8b051d40861ecc416794")
+var NodeInfoOracleAddress = common.HexToAddress("58a7c88ad1f32e7252bebba54def98d3e7b3df11")
+
+var GovernanceABI *OracleContractABI
+var NodeInfoOracleABI *OracleContractABI
+
+func init() {
+	GovernanceABI = NewOracleContractABI(GovernanceABIJSON)
+	NodeInfoOracleABI = NewOracleContractABI(NodeInfoOracleABIJSON)
+}
+
+// OracleContract represent special system contracts written in Go.
+type OracleContract interface {
+	Run(evm *EVM, input []byte, contract *Contract) (ret []byte, err error)
+}
+
+// A map representing available system oracle contracts.
+var OracleContracts = map[common.Address]OracleContract{
+	GovernanceContractAddress: &GovernanceContract{},
+	NodeInfoOracleAddress:     &NodeInfoOracleContract{},
+}
+
+// Run oracle contract.
+func RunOracleContract(oracle OracleContract, evm *EVM, input []byte, contract *Contract) (ret []byte, err error) {
+	return oracle.Run(evm, input, contract)
+}
+
+// OracleContractABI represents ABI information for a given contract.
+type OracleContractABI struct {
+	ABI         abi.ABI
+	Name2Method map[string]abi.Method
+	Sig2Method  map[string]abi.Method
+	Events      map[string]abi.Event
+}
+
+// NewOracleContractABI parse the ABI.
+func NewOracleContractABI(abiDefinition string) *OracleContractABI {
+	abiObject, err := abi.JSON(strings.NewReader(abiDefinition))
+	if err != nil {
+		panic(err)
+	}
+
+	sig2Method := make(map[string]abi.Method)
+	name2Method := make(map[string]abi.Method)
+
+	for _, method := range abiObject.Methods {
+		sig2Method[string(method.Id())] = method
+		name2Method[method.Name] = method
+	}
+
+	events := make(map[string]abi.Event)
+	for _, event := range abiObject.Events {
+		events[event.Name] = event
+	}
+
+	return &OracleContractABI{
+		ABI:         abiObject,
+		Name2Method: name2Method,
+		Sig2Method:  sig2Method,
+		Events:      events,
+	}
+}