diff options
Diffstat (limited to 'accounts/abi/bind/backends')
-rw-r--r-- | accounts/abi/bind/backends/nil.go | 46 | ||||
-rw-r--r-- | accounts/abi/bind/backends/remote.go | 202 | ||||
-rw-r--r-- | accounts/abi/bind/backends/simulated.go | 184 |
3 files changed, 432 insertions, 0 deletions
diff --git a/accounts/abi/bind/backends/nil.go b/accounts/abi/bind/backends/nil.go new file mode 100644 index 000000000..8b1f9d63e --- /dev/null +++ b/accounts/abi/bind/backends/nil.go @@ -0,0 +1,46 @@ +// Copyright 2016 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum 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 go-ethereum 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 go-ethereum library. If not, see <http://www.gnu.org/licenses/>. + +package backends + +import ( + "math/big" + + "github.com/ethereum/go-ethereum/accounts/abi/bind" + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/core/types" +) + +// nilBackend implements bind.ContractBackend, but panics on any method call. +// Its sole purpose is to support the binding tests to construct the generated +// wrappers without calling any methods on them. +type nilBackend struct{} + +func (*nilBackend) ContractCall(common.Address, []byte, bool) ([]byte, error) { + panic("not implemented") +} +func (*nilBackend) GasLimit(common.Address, *common.Address, *big.Int, []byte) (*big.Int, error) { + panic("not implemented") +} +func (*nilBackend) GasPrice() (*big.Int, error) { panic("not implemented") } +func (*nilBackend) AccountNonce(common.Address) (uint64, error) { panic("not implemented") } +func (*nilBackend) SendTransaction(*types.Transaction) error { panic("not implemented") } + +// NewNilBackend creates a new binding backend that can be used for instantiation +// but will panic on any invocation. Its sole purpose is to help testing. +func NewNilBackend() bind.ContractBackend { + return new(nilBackend) +} diff --git a/accounts/abi/bind/backends/remote.go b/accounts/abi/bind/backends/remote.go new file mode 100644 index 000000000..7177809bb --- /dev/null +++ b/accounts/abi/bind/backends/remote.go @@ -0,0 +1,202 @@ +// Copyright 2016 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum 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 go-ethereum 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 go-ethereum library. If not, see <http://www.gnu.org/licenses/>. + +package backends + +import ( + "encoding/json" + "fmt" + "math/big" + "sync" + "sync/atomic" + + "github.com/ethereum/go-ethereum/accounts/abi/bind" + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/core/types" + "github.com/ethereum/go-ethereum/rlp" + "github.com/ethereum/go-ethereum/rpc" +) + +// rpcBackend implements bind.ContractBackend, and acts as the data provider to +// Ethereum contracts bound to Go structs. It uses an RPC connection to delegate +// all its functionality. +// +// Note: The current implementation is a blocking one. This should be replaced +// by a proper async version when a real RPC client is created. +type rpcBackend struct { + client rpc.Client // RPC client connection to interact with an API server + autoid uint32 // ID number to use for the next API request + lock sync.Mutex // Singleton access until we get to request multiplexing +} + +// NewRPCBackend creates a new binding backend to an RPC provider that can be +// used to interact with remote contracts. +func NewRPCBackend(client rpc.Client) bind.ContractBackend { + return &rpcBackend{ + client: client, + } +} + +// request is a JSON RPC request package assembled internally from the client +// method calls. +type request struct { + JsonRpc string `json:"jsonrpc"` // Version of the JSON RPC protocol, always set to 2.0 + Id int `json:"id"` // Auto incrementing ID number for this request + Method string `json:"method"` // Remote procedure name to invoke on the server + Params []interface{} `json:"params"` // List of parameters to pass through (keep types simple) +} + +// response is a JSON RPC response package sent back from the API server. +type response struct { + JsonRpc string `json:"jsonrpc"` // Version of the JSON RPC protocol, always set to 2.0 + Id int `json:"id"` // Auto incrementing ID number for this request + Error json.RawMessage `json:"error"` // Any error returned by the remote side + Result json.RawMessage `json:"result"` // Whatever the remote side sends us in reply +} + +// request forwards an API request to the RPC server, and parses the response. +// +// This is currently painfully non-concurrent, but it will have to do until we +// find the time for niceties like this :P +func (backend *rpcBackend) request(method string, params []interface{}) (json.RawMessage, error) { + backend.lock.Lock() + defer backend.lock.Unlock() + + // Ugly hack to serialize an empty list properly + if params == nil { + params = []interface{}{} + } + // Assemble the request object + req := &request{ + JsonRpc: "2.0", + Id: int(atomic.AddUint32(&backend.autoid, 1)), + Method: method, + Params: params, + } + if err := backend.client.Send(req); err != nil { + return nil, err + } + res := new(response) + if err := backend.client.Recv(res); err != nil { + return nil, err + } + if len(res.Error) > 0 { + return nil, fmt.Errorf("remote error: %s", string(res.Error)) + } + return res.Result, nil +} + +// ContractCall implements ContractCaller.ContractCall, delegating the execution of +// a contract call to the remote node, returning the reply to for local processing. +func (b *rpcBackend) ContractCall(contract common.Address, data []byte, pending bool) ([]byte, error) { + // Pack up the request into an RPC argument + args := struct { + To common.Address `json:"to"` + Data string `json:"data"` + }{ + To: contract, + Data: common.ToHex(data), + } + // Execute the RPC call and retrieve the response + block := "latest" + if pending { + block = "pending" + } + res, err := b.request("eth_call", []interface{}{args, block}) + if err != nil { + return nil, err + } + var hex string + if err := json.Unmarshal(res, &hex); err != nil { + return nil, err + } + // Convert the response back to a Go byte slice and return + return common.FromHex(hex), nil +} + +// AccountNonce implements ContractTransactor.AccountNonce, delegating the +// current account nonce retrieval to the remote node. +func (b *rpcBackend) AccountNonce(account common.Address) (uint64, error) { + res, err := b.request("eth_getTransactionCount", []interface{}{account.Hex(), "pending"}) + if err != nil { + return 0, err + } + var hex string + if err := json.Unmarshal(res, &hex); err != nil { + return 0, err + } + return new(big.Int).SetBytes(common.FromHex(hex)).Uint64(), nil +} + +// GasPrice implements ContractTransactor.GasPrice, delegating the gas price +// oracle request to the remote node. +func (b *rpcBackend) GasPrice() (*big.Int, error) { + res, err := b.request("eth_gasPrice", nil) + if err != nil { + return nil, err + } + var hex string + if err := json.Unmarshal(res, &hex); err != nil { + return nil, err + } + return new(big.Int).SetBytes(common.FromHex(hex)), nil +} + +// GasLimit implements ContractTransactor.GasLimit, delegating the gas estimation +// to the remote node. +func (b *rpcBackend) GasLimit(sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error) { + // Pack up the request into an RPC argument + args := struct { + From common.Address `json:"from"` + To *common.Address `json:"to"` + Value *rpc.HexNumber `json:"value"` + Data string `json:"data"` + }{ + From: sender, + To: contract, + Data: common.ToHex(data), + Value: rpc.NewHexNumber(value), + } + // Execute the RPC call and retrieve the response + res, err := b.request("eth_estimateGas", []interface{}{args}) + if err != nil { + return nil, err + } + var hex string + if err := json.Unmarshal(res, &hex); err != nil { + return nil, err + } + // Convert the response back to a Go byte slice and return + return new(big.Int).SetBytes(common.FromHex(hex)), nil +} + +// Transact implements ContractTransactor.SendTransaction, delegating the raw +// transaction injection to the remote node. +func (b *rpcBackend) SendTransaction(tx *types.Transaction) error { + data, err := rlp.EncodeToBytes(tx) + if err != nil { + return err + } + res, err := b.request("eth_sendRawTransaction", []interface{}{common.ToHex(data)}) + if err != nil { + return err + } + var hex string + if err := json.Unmarshal(res, &hex); err != nil { + return err + } + return nil +} diff --git a/accounts/abi/bind/backends/simulated.go b/accounts/abi/bind/backends/simulated.go new file mode 100644 index 000000000..17a0ed7fe --- /dev/null +++ b/accounts/abi/bind/backends/simulated.go @@ -0,0 +1,184 @@ +// Copyright 2016 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum 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 go-ethereum 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 go-ethereum library. If not, see <http://www.gnu.org/licenses/>. + +package backends + +import ( + "math/big" + + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/core" + "github.com/ethereum/go-ethereum/core/state" + "github.com/ethereum/go-ethereum/core/types" + "github.com/ethereum/go-ethereum/ethdb" + "github.com/ethereum/go-ethereum/event" +) + +// SimulatedBackend implements bind.ContractBackend, simulating a blockchain in +// the background. Its main purpose is to allow easily testing contract bindings. +type SimulatedBackend struct { + database ethdb.Database // In memory database to store our testing data + blockchain *core.BlockChain // Ethereum blockchain to handle the consensus + + pendingBlock *types.Block // Currently pending block that will be imported on request + pendingState *state.StateDB // Currently pending state that will be the active on on request +} + +// NewSimulatedBackend creates a new binding backend using a simulated blockchain +// for testing purposes. +func NewSimulatedBackend(accounts ...core.GenesisAccount) *SimulatedBackend { + database, _ := ethdb.NewMemDatabase() + core.WriteGenesisBlockForTesting(database, accounts...) + blockchain, _ := core.NewBlockChain(database, new(core.FakePow), new(event.TypeMux)) + + backend := &SimulatedBackend{ + database: database, + blockchain: blockchain, + } + backend.Rollback() + + return backend +} + +// Commit imports all the pending transactions as a single block and starts a +// fresh new state. +func (b *SimulatedBackend) Commit() { + if _, err := b.blockchain.InsertChain([]*types.Block{b.pendingBlock}); err != nil { + panic(err) // This cannot happen unless the simulator is wrong, fail in that case + } + b.Rollback() +} + +// Rollback aborts all pending transactions, reverting to the last committed state. +func (b *SimulatedBackend) Rollback() { + blocks, _ := core.GenerateChain(b.blockchain.CurrentBlock(), b.database, 1, func(int, *core.BlockGen) {}) + + b.pendingBlock = blocks[0] + b.pendingState, _ = state.New(b.pendingBlock.Root(), b.database) +} + +// ContractCall implements ContractCaller.ContractCall, executing the specified +// contract with the given input data. +func (b *SimulatedBackend) ContractCall(contract common.Address, data []byte, pending bool) ([]byte, error) { + // Create a copy of the current state db to screw around with + var ( + block *types.Block + statedb *state.StateDB + ) + if pending { + block, statedb = b.pendingBlock, b.pendingState + } else { + block = b.blockchain.CurrentBlock() + statedb, _ = b.blockchain.State() + } + statedb = statedb.Copy() + + // Set infinite balance to the a fake caller account + from := statedb.GetOrNewStateObject(common.Address{}) + from.SetBalance(common.MaxBig) + + // Assemble the call invocation to measure the gas usage + msg := callmsg{ + from: from, + to: &contract, + gasPrice: new(big.Int), + gasLimit: common.MaxBig, + value: new(big.Int), + data: data, + } + // Execute the call and return + vmenv := core.NewEnv(statedb, b.blockchain, msg, block.Header()) + gaspool := new(core.GasPool).AddGas(common.MaxBig) + + out, _, err := core.ApplyMessage(vmenv, msg, gaspool) + return out, err +} + +// AccountNonce implements ContractTransactor.AccountNonce, retrieving the nonce +// currently pending for the account. +func (b *SimulatedBackend) AccountNonce(account common.Address) (uint64, error) { + return b.pendingState.GetOrNewStateObject(account).Nonce(), nil +} + +// GasPrice implements ContractTransactor.GasPrice. Since the simulated chain +// doens't have miners, we just return a gas price of 1 for any call. +func (b *SimulatedBackend) GasPrice() (*big.Int, error) { + return big.NewInt(1), nil +} + +// GasLimit implements ContractTransactor.GasLimit, executing the requested code +// against the currently pending block/state and returning the used gas. +func (b *SimulatedBackend) GasLimit(sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error) { + // Create a copy of the currently pending state db to screw around with + var ( + block = b.pendingBlock + statedb = b.pendingState.Copy() + ) + + // Set infinite balance to the a fake caller account + from := statedb.GetOrNewStateObject(sender) + from.SetBalance(common.MaxBig) + + // Assemble the call invocation to measure the gas usage + msg := callmsg{ + from: from, + to: contract, + gasPrice: new(big.Int), + gasLimit: common.MaxBig, + value: value, + data: data, + } + // Execute the call and return + vmenv := core.NewEnv(statedb, b.blockchain, msg, block.Header()) + gaspool := new(core.GasPool).AddGas(common.MaxBig) + + _, gas, err := core.ApplyMessage(vmenv, msg, gaspool) + return gas, err +} + +// Transact implements ContractTransactor.SendTransaction, delegating the raw +// transaction injection to the remote node. +func (b *SimulatedBackend) SendTransaction(tx *types.Transaction) error { + blocks, _ := core.GenerateChain(b.blockchain.CurrentBlock(), b.database, 1, func(number int, block *core.BlockGen) { + for _, tx := range b.pendingBlock.Transactions() { + block.AddTx(tx) + } + block.AddTx(tx) + }) + b.pendingBlock = blocks[0] + b.pendingState, _ = state.New(b.pendingBlock.Root(), b.database) + + return nil +} + +// callmsg implements core.Message to allow passing it as a transaction simulator. +type callmsg struct { + from *state.StateObject + to *common.Address + gasLimit *big.Int + gasPrice *big.Int + value *big.Int + data []byte +} + +func (m callmsg) From() (common.Address, error) { return m.from.Address(), nil } +func (m callmsg) FromFrontier() (common.Address, error) { return m.from.Address(), nil } +func (m callmsg) Nonce() uint64 { return m.from.Nonce() } +func (m callmsg) To() *common.Address { return m.to } +func (m callmsg) GasPrice() *big.Int { return m.gasPrice } +func (m callmsg) Gas() *big.Int { return m.gasLimit } +func (m callmsg) Value() *big.Int { return m.value } +func (m callmsg) Data() []byte { return m.data } |