lntest: add BitcoindBackendCfg

lntest/bitcoind.go

@@ -0,0 +1,184 @@
+// +build bitcoind
+
+package lntest
+
+import (
+	"fmt"
+	"io/ioutil"
+	"math/rand"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"time"
+
+	"github.com/btcsuite/btcd/chaincfg"
+	"github.com/btcsuite/btcd/rpcclient"
+)
+
+// logDir is the name of the temporary log directory.
+const logDir = "./.backendlogs"
+
+// BitcoindBackendConfig is an implementation of the BackendConfig interface
+// backed by a Bitcoind node.
+type BitcoindBackendConfig struct {
+	rpcHost      string
+	rpcUser      string
+	rpcPass      string
+	zmqBlockPath string
+	zmqTxPath    string
+	p2pPort      int
+	rpcClient    *rpcclient.Client
+
+	// minerAddr is the p2p address of the miner to connect to.
+	minerAddr string
+}
+
+// A compile time assertion to ensure BitcoindBackendConfig meets the
+// BackendConfig interface.
+var _ BackendConfig = (*BitcoindBackendConfig)(nil)
+
+// GenArgs returns the arguments needed to be passed to LND at startup for
+// using this node as a chain backend.
+func (b BitcoindBackendConfig) GenArgs() []string {
+	var args []string
+	args = append(args, "--bitcoin.node=bitcoind")
+	args = append(args, fmt.Sprintf("--bitcoind.rpchost=%v", b.rpcHost))
+	args = append(args, fmt.Sprintf("--bitcoind.rpcuser=%v", b.rpcUser))
+	args = append(args, fmt.Sprintf("--bitcoind.rpcpass=%v", b.rpcPass))
+	args = append(args, fmt.Sprintf("--bitcoind.zmqpubrawblock=%v",
+		b.zmqBlockPath))
+	args = append(args, fmt.Sprintf("--bitcoind.zmqpubrawtx=%v",
+		b.zmqTxPath))
+
+	return args
+}
+
+// ConnectMiner is called to establish a connection to the test miner.
+func (b BitcoindBackendConfig) ConnectMiner() error {
+	return b.rpcClient.AddNode(b.minerAddr, rpcclient.ANAdd)
+}
+
+// DisconnectMiner is called to disconnect the miner.
+func (b BitcoindBackendConfig) DisconnectMiner() error {
+	return b.rpcClient.AddNode(b.minerAddr, rpcclient.ANRemove)
+}
+
+// Name returns the name of the backend type.
+func (b BitcoindBackendConfig) Name() string {
+	return "bitcoind"
+}
+
+// NewBackend starts a bitcoind node and returns a BitoindBackendConfig for
+// that node.
+func NewBackend(miner string, netParams *chaincfg.Params) (
+	*BitcoindBackendConfig, func(), error) {
+
+	if netParams != &chaincfg.RegressionNetParams {
+		return nil, nil, fmt.Errorf("only regtest supported")
+	}
+
+	if err := os.MkdirAll(logDir, 0700); err != nil {
+		return nil, nil, err
+	}
+
+	logFile, err := filepath.Abs(logDir + "/bitcoind.log")
+	if err != nil {
+		return nil, nil, err
+	}
+
+	tempBitcoindDir, err := ioutil.TempDir("", "bitcoind")
+	if err != nil {
+		return nil, nil,
+			fmt.Errorf("unable to create temp directory: %v", err)
+	}
+
+	zmqBlockPath := "ipc:///" + tempBitcoindDir + "/blocks.socket"
+	zmqTxPath := "ipc:///" + tempBitcoindDir + "/txs.socket"
+	rpcPort := rand.Int()%(65536-1024) + 1024
+	p2pPort := rand.Int()%(65536-1024) + 1024
+
+	bitcoind := exec.Command(
+		"bitcoind",
+		"-datadir="+tempBitcoindDir,
+		"-regtest",
+		"-txindex",
+		"-whitelist=127.0.0.1", // whitelist localhost to speed up relay
+		"-rpcauth=weks:469e9bb14ab2360f8e226efed5ca6f"+
+			"d$507c670e800a95284294edb5773b05544b"+
+			"220110063096c221be9933c82d38e1",
+		fmt.Sprintf("-rpcport=%d", rpcPort),
+		fmt.Sprintf("-port=%d", p2pPort),
+		"-disablewallet",
+		"-zmqpubrawblock="+zmqBlockPath,
+		"-zmqpubrawtx="+zmqTxPath,
+		"-debuglogfile="+logFile,
+	)
+
+	err = bitcoind.Start()
+	if err != nil {
+		os.RemoveAll(tempBitcoindDir)
+		return nil, nil, fmt.Errorf("couldn't start bitcoind: %v", err)
+	}
+
+	cleanUp := func() {
+		bitcoind.Process.Kill()
+		bitcoind.Wait()
+
+		// After shutting down the chain backend, we'll make a copy of
+		// the log file before deleting the temporary log dir.
+		err := CopyFile("./output_bitcoind_chainbackend.log", logFile)
+		if err != nil {
+			fmt.Printf("unable to copy file: %v\n", err)
+		}
+		if err = os.RemoveAll(logDir); err != nil {
+			fmt.Printf("Cannot remove dir %s: %v\n", logDir, err)
+		}
+
+		os.RemoveAll(tempBitcoindDir)
+	}
+
+	// Allow process to start.
+	time.Sleep(1 * time.Second)
+
+	rpcHost := fmt.Sprintf("127.0.0.1:%d", rpcPort)
+	rpcUser := "weks"
+	rpcPass := "weks"
+
+	rpcCfg := rpcclient.ConnConfig{
+		Host:                 rpcHost,
+		User:                 rpcUser,
+		Pass:                 rpcPass,
+		DisableConnectOnNew:  true,
+		DisableAutoReconnect: false,
+		DisableTLS:           true,
+		HTTPPostMode:         true,
+	}
+
+	client, err := rpcclient.New(&rpcCfg, nil)
+	if err != nil {
+		cleanUp()
+		return nil, nil, fmt.Errorf("unable to create rpc client: %v",
+			err)
+	}
+
+	// We start by adding the miner to the bitcoind addnode list. We do
+	// this instead of connecting using command line flags, because it will
+	// allow us to disconnect the miner using the AddNode command later.
+	if err := client.AddNode(miner, rpcclient.ANAdd); err != nil {
+		cleanUp()
+		return nil, nil, fmt.Errorf("unable to add node: %v", err)
+	}
+
+	bd := BitcoindBackendConfig{
+		rpcHost:      rpcHost,
+		rpcUser:      rpcUser,
+		rpcPass:      rpcPass,
+		zmqBlockPath: zmqBlockPath,
+		zmqTxPath:    zmqTxPath,
+		p2pPort:      p2pPort,
+		rpcClient:    client,
+		minerAddr:    miner,
+	}
+
+	return &bd, cleanUp, nil
+}