node_client.go

// Copyright 2017 Monax Industries Limited
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package client

import (
	"fmt"
	// "strings"

	"github.com/tendermint/go-rpc/client"

	acc "github.com/hyperledger/burrow/account"
	consensus_types "github.com/hyperledger/burrow/consensus/types"
	core_types "github.com/hyperledger/burrow/core/types"
	"github.com/hyperledger/burrow/logging"
	"github.com/hyperledger/burrow/logging/loggers"
	tendermint_client "github.com/hyperledger/burrow/rpc/tendermint/client"
	tendermint_types "github.com/hyperledger/burrow/rpc/tendermint/core/types"
	"github.com/hyperledger/burrow/txs"
	tmLog15 "github.com/tendermint/log15"
)

type NodeClient interface {
	Broadcast(transaction txs.Tx) (*txs.Receipt, error)
	DeriveWebsocketClient() (nodeWsClient NodeWebsocketClient, err error)

	Status() (ChainId []byte, ValidatorPublicKey []byte, LatestBlockHash []byte,
		LatestBlockHeight int, LatestBlockTime int64, err error)
	GetAccount(address []byte) (*acc.Account, error)
	QueryContract(callerAddress, calleeAddress, data []byte) (ret []byte, gasUsed int64, err error)
	QueryContractCode(address, code, data []byte) (ret []byte, gasUsed int64, err error)

	DumpStorage(address []byte) (storage *core_types.Storage, err error)
	GetName(name string) (owner []byte, data string, expirationBlock int, err error)
	ListValidators() (blockHeight int, bondedValidators, unbondingValidators []consensus_types.Validator, err error)

	// Logging context for this NodeClient
	Logger() loggers.InfoTraceLogger
}

type NodeWebsocketClient interface {
	Subscribe(eventId string) error
	Unsubscribe(eventId string) error

	WaitForConfirmation(tx txs.Tx, chainId string, inputAddr []byte) (chan Confirmation, error)
	Close()
}

// NOTE [ben] Compiler check to ensure burrowNodeClient successfully implements
// burrow/client.NodeClient
var _ NodeClient = (*burrowNodeClient)(nil)

// burrow-client is a simple struct exposing the client rpc methods
type burrowNodeClient struct {
	broadcastRPC string
	logger       loggers.InfoTraceLogger
}

// BurrowKeyClient.New returns a new monax-keys client for provided rpc location
// Monax-keys connects over http request-responses
func NewBurrowNodeClient(rpcString string, logger loggers.InfoTraceLogger) *burrowNodeClient {
	return &burrowNodeClient{
		broadcastRPC: rpcString,
		logger:       logging.WithScope(logger, "BurrowNodeClient"),
	}
}

// Note [Ben]: This is a hack to silence Tendermint logger from tendermint/go-rpc
// it needs to be initialised before go-rpc, hence it's placement here.
func init() {
	h := tmLog15.LvlFilterHandler(tmLog15.LvlWarn, tmLog15.StdoutHandler)
	tmLog15.Root().SetHandler(h)
}

//------------------------------------------------------------------------------------
// broadcast to blockchain node

func (burrowNodeClient *burrowNodeClient) Broadcast(tx txs.Tx) (*txs.Receipt, error) {
	client := rpcclient.NewClientURI(burrowNodeClient.broadcastRPC)
	receipt, err := tendermint_client.BroadcastTx(client, tx)
	if err != nil {
		return nil, err
	}
	return &receipt, nil
}

func (burrowNodeClient *burrowNodeClient) DeriveWebsocketClient() (nodeWsClient NodeWebsocketClient, err error) {
	var wsAddr string
	// TODO: clean up this inherited mess on dealing with the address prefixes.
	nodeAddr := burrowNodeClient.broadcastRPC
	// if strings.HasPrefix(nodeAddr, "http://") {
	// 	wsAddr = strings.TrimPrefix(nodeAddr, "http://")
	// }
	// if strings.HasPrefix(nodeAddr, "tcp://") {
	// 	wsAddr = strings.TrimPrefix(nodeAddr, "tcp://")
	// }
	// if strings.HasPrefix(nodeAddr, "unix://") {
	// 	log.WithFields(log.Fields{
	// 		"node address": nodeAddr,
	// 	}).Error("Unable to subscribe to websocket from unix socket.")
	// 	return nil, fmt.Errorf("Unable to construct websocket from unix socket: %s", nodeAddr)
	// }
	// wsAddr = "ws://" + wsAddr
	wsAddr = nodeAddr
	logging.TraceMsg(burrowNodeClient.logger, "Subscribing to websocket address",
		"websocket address", wsAddr,
		"endpoint", "/websocket",
	)
	wsClient := rpcclient.NewWSClient(wsAddr, "/websocket")
	if _, err = wsClient.Start(); err != nil {
		return nil, err
	}
	derivedBurrowNodeWebsocketClient := &burrowNodeWebsocketClient{
		tendermintWebsocket: wsClient,
		logger:              logging.WithScope(burrowNodeClient.logger, "BurrowNodeWebsocketClient"),
	}
	return derivedBurrowNodeWebsocketClient, nil
}

//------------------------------------------------------------------------------------
// RPC requests other than transaction related

// Status returns the ChainId (GenesisHash), validator's PublicKey, latest block hash
// the block height and the latest block time.
func (burrowNodeClient *burrowNodeClient) Status() (GenesisHash []byte, ValidatorPublicKey []byte, LatestBlockHash []byte, LatestBlockHeight int, LatestBlockTime int64, err error) {
	client := rpcclient.NewClientJSONRPC(burrowNodeClient.broadcastRPC)
	res, err := tendermint_client.Status(client)
	if err != nil {
		err = fmt.Errorf("Error connecting to node (%s) to get status: %s",
			burrowNodeClient.broadcastRPC, err.Error())
		return nil, nil, nil, int(0), int64(0), err
	}

	// unwrap return results
	GenesisHash = res.GenesisHash
	ValidatorPublicKey = res.PubKey.Bytes()
	LatestBlockHash = res.LatestBlockHash
	LatestBlockHeight = res.LatestBlockHeight
	LatestBlockTime = res.LatestBlockTime
	return
}

func (burrowNodeClient *burrowNodeClient) ChainId() (ChainName, ChainId string, GenesisHash []byte, err error) {
	client := rpcclient.NewClientJSONRPC(burrowNodeClient.broadcastRPC)
	chainIdResult, err := tendermint_client.ChainId(client)
	if err != nil {
		err = fmt.Errorf("Error connecting to node (%s) to get chain id: %s",
			burrowNodeClient.broadcastRPC, err.Error())
		return "", "", nil, err
	}
	// unwrap results
	ChainName = chainIdResult.ChainName
	ChainId = chainIdResult.ChainId
	GenesisHash = make([]byte, len(chainIdResult.GenesisHash))
	copy(GenesisHash[:], chainIdResult.GenesisHash)
	return
}

// QueryContract executes the contract code at address with the given data
// NOTE: there is no check on the caller;
func (burrowNodeClient *burrowNodeClient) QueryContract(callerAddress, calleeAddress, data []byte) (ret []byte, gasUsed int64, err error) {
	client := rpcclient.NewClientJSONRPC(burrowNodeClient.broadcastRPC)
	callResult, err := tendermint_client.Call(client, callerAddress, calleeAddress, data)
	if err != nil {
		err = fmt.Errorf("Error connnecting to node (%s) to query contract at (%X) with data (%X)",
			burrowNodeClient.broadcastRPC, calleeAddress, data, err.Error())
		return nil, int64(0), err
	}
	return callResult.Return, callResult.GasUsed, nil
}

// QueryContractCode executes the contract code at address with the given data but with provided code
func (burrowNodeClient *burrowNodeClient) QueryContractCode(address, code, data []byte) (ret []byte, gasUsed int64, err error) {
	client := rpcclient.NewClientJSONRPC(burrowNodeClient.broadcastRPC)
	// TODO: [ben] Call and CallCode have an inconsistent signature; it makes sense for both to only
	// have a single address that is the contract to query.
	callResult, err := tendermint_client.CallCode(client, address, code, data)
	if err != nil {
		err = fmt.Errorf("Error connnecting to node (%s) to query contract code at (%X) with data (%X) and code (%X)",
			burrowNodeClient.broadcastRPC, address, data, code, err.Error())
		return nil, int64(0), err
	}
	return callResult.Return, callResult.GasUsed, nil
}

// GetAccount returns a copy of the account
func (burrowNodeClient *burrowNodeClient) GetAccount(address []byte) (*acc.Account, error) {
	client := rpcclient.NewClientJSONRPC(burrowNodeClient.broadcastRPC)
	account, err := tendermint_client.GetAccount(client, address)
	if err != nil {
		err = fmt.Errorf("Error connecting to node (%s) to fetch account (%X): %s",
			burrowNodeClient.broadcastRPC, address, err.Error())
		return nil, err
	}
	if account == nil {
		err = fmt.Errorf("Unknown account %X at node (%s)", address, burrowNodeClient.broadcastRPC)
		return nil, err
	}

	return account.Copy(), nil
}

// DumpStorage returns the full storage for an account.
func (burrowNodeClient *burrowNodeClient) DumpStorage(address []byte) (storage *core_types.Storage, err error) {
	client := rpcclient.NewClientJSONRPC(burrowNodeClient.broadcastRPC)
	resultStorage, err := tendermint_client.DumpStorage(client, address)
	if err != nil {
		err = fmt.Errorf("Error connecting to node (%s) to get storage for account (%X): %s",
			burrowNodeClient.broadcastRPC, address, err.Error())
		return nil, err
	}
	// UnwrapResultDumpStorage is an inefficient full deep copy,
	// to transform the type to /core/types.Storage
	// TODO: removing go-wire and go-rpc allows us to collapse these types
	storage = tendermint_types.UnwrapResultDumpStorage(resultStorage)
	return
}

//--------------------------------------------------------------------------------------------
// Name registry

func (burrowNodeClient *burrowNodeClient) GetName(name string) (owner []byte, data string, expirationBlock int, err error) {
	client := rpcclient.NewClientJSONRPC(burrowNodeClient.broadcastRPC)
	entryResult, err := tendermint_client.GetName(client, name)
	if err != nil {
		err = fmt.Errorf("Error connecting to node (%s) to get name registrar entry for name (%s)",
			burrowNodeClient.broadcastRPC, name)
		return nil, "", 0, err
	}
	// unwrap return results
	owner = entryResult.Owner
	data = entryResult.Data
	expirationBlock = entryResult.Expires
	return
}

//--------------------------------------------------------------------------------------------

func (burrowNodeClient *burrowNodeClient) ListValidators() (blockHeight int,
	bondedValidators []consensus_types.Validator, unbondingValidators []consensus_types.Validator, err error) {
	client := rpcclient.NewClientJSONRPC(burrowNodeClient.broadcastRPC)
	validatorsResult, err := tendermint_client.ListValidators(client)
	if err != nil {
		err = fmt.Errorf("Error connecting to node (%s) to get validators",
			burrowNodeClient.broadcastRPC)
		return 0, nil, nil, err
	}
	// unwrap return results
	blockHeight = validatorsResult.BlockHeight
	bondedValidators = validatorsResult.BondedValidators
	unbondingValidators = validatorsResult.UnbondingValidators
	return
}

func (burrowNodeClient *burrowNodeClient) Logger() loggers.InfoTraceLogger {
	return burrowNodeClient.logger
}