package lntest import ( "fmt" "io/ioutil" "sync" "time" "golang.org/x/net/context" "google.golang.org/grpc/grpclog" "github.com/lightningnetwork/lnd/lnrpc" "github.com/roasbeef/btcd/chaincfg" "github.com/roasbeef/btcd/chaincfg/chainhash" "github.com/roasbeef/btcd/integration/rpctest" "github.com/roasbeef/btcd/rpcclient" "github.com/roasbeef/btcd/txscript" "github.com/roasbeef/btcd/wire" "github.com/roasbeef/btcutil" ) // NetworkHarness is an integration testing harness for the lightning network. // The harness by default is created with two active nodes on the network: // Alice and Bob. type NetworkHarness struct { rpcConfig rpcclient.ConnConfig netParams *chaincfg.Params // Miner is a reference to a running full node that can be used to create // new blocks on the network. Miner *rpctest.Harness activeNodes map[int]*HarnessNode nodesByPub map[string]*HarnessNode // Alice and Bob are the initial seeder nodes that are automatically // created to be the initial participants of the test network. Alice *HarnessNode Bob *HarnessNode seenTxns chan *chainhash.Hash bitcoinWatchRequests chan *txWatchRequest // Channel for transmitting stderr output from failed lightning node // to main process. lndErrorChan chan error quit chan struct{} mtx sync.Mutex } // NewNetworkHarness creates a new network test harness. // TODO(roasbeef): add option to use golang's build library to a binary of the // current repo. This'll save developers from having to manually `go install` // within the repo each time before changes func NewNetworkHarness(r *rpctest.Harness) (*NetworkHarness, error) { n := NetworkHarness{ activeNodes: make(map[int]*HarnessNode), nodesByPub: make(map[string]*HarnessNode), seenTxns: make(chan *chainhash.Hash), bitcoinWatchRequests: make(chan *txWatchRequest), lndErrorChan: make(chan error), netParams: r.ActiveNet, Miner: r, rpcConfig: r.RPCConfig(), quit: make(chan struct{}), } go n.networkWatcher() return &n, nil } // LookUpNodeByPub queries the set of active nodes to locate a node according // to its public key. The second value will be true if the node was found, and // false otherwise. func (n *NetworkHarness) LookUpNodeByPub(pubStr string) (*HarnessNode, error) { n.mtx.Lock() defer n.mtx.Unlock() node, ok := n.nodesByPub[pubStr] if !ok { return nil, fmt.Errorf("unable to find node") } return node, nil } // ProcessErrors returns a channel used for reporting any fatal process errors. // If any of the active nodes within the harness' test network incur a fatal // error, that error is sent over this channel. func (n *NetworkHarness) ProcessErrors() <-chan error { return n.lndErrorChan } // fakeLogger is a fake grpclog.Logger implementation. This is used to stop // grpc's logger from printing directly to stdout. type fakeLogger struct{} func (f *fakeLogger) Fatal(args ...interface{}) {} func (f *fakeLogger) Fatalf(format string, args ...interface{}) {} func (f *fakeLogger) Fatalln(args ...interface{}) {} func (f *fakeLogger) Print(args ...interface{}) {} func (f *fakeLogger) Printf(format string, args ...interface{}) {} func (f *fakeLogger) Println(args ...interface{}) {} // SetUp starts the initial seeder nodes within the test harness. The initial // node's wallets will be funded wallets with ten 1 BTC outputs each. Finally // rpc clients capable of communicating with the initial seeder nodes are // created. Nodes are initialized with the given extra command line flags, which // should be formatted properly - "--arg=value". func (n *NetworkHarness) SetUp(lndArgs []string) error { // Swap out grpc's default logger with out fake logger which drops the // statements on the floor. grpclog.SetLogger(&fakeLogger{}) // Start the initial seeder nodes within the test network, then connect // their respective RPC clients. var wg sync.WaitGroup errChan := make(chan error, 2) wg.Add(2) go func() { defer wg.Done() node, err := n.NewNode(lndArgs) if err != nil { errChan <- err return } n.Alice = node }() go func() { defer wg.Done() node, err := n.NewNode(lndArgs) if err != nil { errChan <- err return } n.Bob = node }() wg.Wait() select { case err := <-errChan: return err default: } // Load up the wallets of the seeder nodes with 10 outputs of 1 BTC // each. ctxb := context.Background() addrReq := &lnrpc.NewAddressRequest{ Type: lnrpc.NewAddressRequest_WITNESS_PUBKEY_HASH, } clients := []lnrpc.LightningClient{n.Alice, n.Bob} for _, client := range clients { for i := 0; i < 10; i++ { resp, err := client.NewAddress(ctxb, addrReq) if err != nil { return err } addr, err := btcutil.DecodeAddress(resp.Address, n.netParams) if err != nil { return err } addrScript, err := txscript.PayToAddrScript(addr) if err != nil { return err } output := &wire.TxOut{ PkScript: addrScript, Value: btcutil.SatoshiPerBitcoin, } if _, err := n.Miner.SendOutputs([]*wire.TxOut{output}, 30); err != nil { return err } } } // We generate several blocks in order to give the outputs created // above a good number of confirmations. if _, err := n.Miner.Node.Generate(10); err != nil { return err } // Finally, make a connection between both of the nodes. if err := n.ConnectNodes(ctxb, n.Alice, n.Bob); err != nil { return err } // Now block until both wallets have fully synced up. expectedBalance := int64(btcutil.SatoshiPerBitcoin * 10) balReq := &lnrpc.WalletBalanceRequest{} balanceTicker := time.Tick(time.Millisecond * 50) balanceTimeout := time.After(time.Second * 30) out: for { select { case <-balanceTicker: aliceResp, err := n.Alice.WalletBalance(ctxb, balReq) if err != nil { return err } bobResp, err := n.Bob.WalletBalance(ctxb, balReq) if err != nil { return err } if aliceResp.ConfirmedBalance == expectedBalance && bobResp.ConfirmedBalance == expectedBalance { break out } case <-balanceTimeout: return fmt.Errorf("balances not synced after deadline") } } return nil } // TearDownAll tears down all active nodes within the test lightning network. func (n *NetworkHarness) TearDownAll() error { for _, node := range n.activeNodes { if err := n.ShutdownNode(node); err != nil { return err } } close(n.lndErrorChan) close(n.quit) return nil } // NewNode fully initializes a returns a new HarnessNode binded to the // current instance of the network harness. The created node is running, but // not yet connected to other nodes within the network. func (n *NetworkHarness) NewNode(extraArgs []string) (*HarnessNode, error) { node, err := newNode(nodeConfig{ RPCConfig: &n.rpcConfig, NetParams: n.netParams, ExtraArgs: extraArgs, }) if err != nil { return nil, err } // Put node in activeNodes to ensure Shutdown is called even if Start // returns an error. n.mtx.Lock() n.activeNodes[node.NodeID] = node n.mtx.Unlock() if err := node.start(n.lndErrorChan); err != nil { return nil, err } // With the node started, we can now record its public key within the // global mapping. n.mtx.Lock() n.nodesByPub[node.PubKeyStr] = node n.mtx.Unlock() return node, nil } // ConnectNodes establishes an encrypted+authenticated p2p connection from node // a towards node b. The function will return a non-nil error if the connection // was unable to be established. // // NOTE: This function may block for up to 15-seconds as it will not return // until the new connection is detected as being known to both nodes. func (n *NetworkHarness) ConnectNodes(ctx context.Context, a, b *HarnessNode) error { bobInfo, err := b.GetInfo(ctx, &lnrpc.GetInfoRequest{}) if err != nil { return err } req := &lnrpc.ConnectPeerRequest{ Addr: &lnrpc.LightningAddress{ Pubkey: bobInfo.IdentityPubkey, Host: b.cfg.P2PAddr(), }, } if _, err := a.ConnectPeer(ctx, req); err != nil { return err } err = WaitPredicate(func() bool { // If node B is seen in the ListPeers response from node A, // then we can exit early as the connection has been fully // established. resp, err := a.ListPeers(ctx, &lnrpc.ListPeersRequest{}) if err != nil { return false } for _, peer := range resp.Peers { if peer.PubKey == b.PubKeyStr { return true } } return false }, time.Second*15) if err != nil { return fmt.Errorf("peers not connected within 15 seconds") } return nil } // DisconnectNodes disconnects node a from node b by sending RPC message // from a node to b node func (n *NetworkHarness) DisconnectNodes(ctx context.Context, a, b *HarnessNode) error { bobInfo, err := b.GetInfo(ctx, &lnrpc.GetInfoRequest{}) if err != nil { return err } req := &lnrpc.DisconnectPeerRequest{ PubKey: bobInfo.IdentityPubkey, } if _, err := a.DisconnectPeer(ctx, req); err != nil { return err } return nil } // RestartNode attempts to restart a lightning node by shutting it down // cleanly, then restarting the process. This function is fully blocking. Upon // restart, the RPC connection to the node will be re-attempted, continuing iff // the connection attempt is successful. If the callback parameter is non-nil, // then the function will be executed after the node shuts down, but *before* // the process has been started up again. // // This method can be useful when testing edge cases such as a node broadcast // and invalidated prior state, or persistent state recovery, simulating node // crashes, etc. func (n *NetworkHarness) RestartNode(node *HarnessNode, callback func() error) error { if err := node.stop(); err != nil { return err } if callback != nil { if err := callback(); err != nil { return err } } return node.start(n.lndErrorChan) } // ShutdownNode stops an active lnd process and returns when the process has // exited and any temporary directories have been cleaned up. func (n *NetworkHarness) ShutdownNode(node *HarnessNode) error { if err := node.shutdown(); err != nil { return err } delete(n.activeNodes, node.NodeID) return nil } // TODO(roasbeef): add a WithChannel higher-order function? // * python-like context manager w.r.t using a channel within a test // * possibly adds more funds to the target wallet if the funds are not // enough // txWatchRequest encapsulates a request to the harness' Bitcoin network // watcher to dispatch a notification once a transaction with the target txid // is seen within the test network. type txWatchRequest struct { txid chainhash.Hash eventChan chan struct{} } // bitcoinNetworkWatcher is a goroutine which accepts async notification // requests for the broadcast of a target transaction, and then dispatches the // transaction once its seen on the Bitcoin network. func (n *NetworkHarness) networkWatcher() { seenTxns := make(map[chainhash.Hash]struct{}) clients := make(map[chainhash.Hash][]chan struct{}) for { select { case <-n.quit: return case req := <-n.bitcoinWatchRequests: // If we've already seen this transaction, then // immediately dispatch the request. Otherwise, append // to the list of clients who are watching for the // broadcast of this transaction. if _, ok := seenTxns[req.txid]; ok { close(req.eventChan) } else { clients[req.txid] = append(clients[req.txid], req.eventChan) } case txid := <-n.seenTxns: // Add this txid to our set of "seen" transactions. So // we're able to dispatch any notifications for this // txid which arrive *after* it's seen within the // network. seenTxns[*txid] = struct{}{} // If there isn't a registered notification for this // transaction then ignore it. txClients, ok := clients[*txid] if !ok { continue } // Otherwise, dispatch the notification to all clients, // cleaning up the now un-needed state. for _, client := range txClients { close(client) } delete(clients, *txid) } } } // OnTxAccepted is a callback to be called each time a new transaction has been // broadcast on the network. func (n *NetworkHarness) OnTxAccepted(hash *chainhash.Hash) { select { case n.seenTxns <- hash: case <-n.quit: return } } // WaitForTxBroadcast blocks until the target txid is seen on the network. If // the transaction isn't seen within the network before the passed timeout, // then an error is returned. // TODO(roasbeef): add another method which creates queue of all seen transactions func (n *NetworkHarness) WaitForTxBroadcast(ctx context.Context, txid chainhash.Hash) error { // Return immediately if harness has been torn down. select { case <-n.quit: return fmt.Errorf("NetworkHarness has been torn down") default: } eventChan := make(chan struct{}) n.bitcoinWatchRequests <- &txWatchRequest{ txid: txid, eventChan: eventChan, } select { case <-eventChan: return nil case <-n.quit: return fmt.Errorf("NetworkHarness has been torn down") case <-ctx.Done(): return fmt.Errorf("tx not seen before context timeout") } } // OpenChannel attempts to open a channel between srcNode and destNode with the // passed channel funding parameters. If the passed context has a timeout, then // if the timeout is reached before the channel pending notification is // received, an error is returned. func (n *NetworkHarness) OpenChannel(ctx context.Context, srcNode, destNode *HarnessNode, amt btcutil.Amount, pushAmt btcutil.Amount, private bool) (lnrpc.Lightning_OpenChannelClient, error) { // Wait until srcNode and destNode have the latest chain synced. // Otherwise, we may run into a check within the funding manager that // prevents any funding workflows from being kicked off if the chain // isn't yet synced. if err := srcNode.WaitForBlockchainSync(ctx); err != nil { return nil, fmt.Errorf("Unable to sync srcNode chain: %v", err) } if err := destNode.WaitForBlockchainSync(ctx); err != nil { return nil, fmt.Errorf("Unable to sync destNode chain: %v", err) } openReq := &lnrpc.OpenChannelRequest{ NodePubkey: destNode.PubKey[:], LocalFundingAmount: int64(amt), PushSat: int64(pushAmt), Private: private, } respStream, err := srcNode.OpenChannel(ctx, openReq) if err != nil { return nil, fmt.Errorf("unable to open channel between "+ "alice and bob: %v", err) } chanOpen := make(chan struct{}) errChan := make(chan error) go func() { // Consume the "channel pending" update. This waits until the node // notifies us that the final message in the channel funding workflow // has been sent to the remote node. resp, err := respStream.Recv() if err != nil { errChan <- err return } if _, ok := resp.Update.(*lnrpc.OpenStatusUpdate_ChanPending); !ok { errChan <- fmt.Errorf("expected channel pending update, "+ "instead got %v", resp) return } close(chanOpen) }() select { case <-ctx.Done(): return nil, fmt.Errorf("timeout reached before chan pending "+ "update sent: %v", err) case err := <-errChan: return nil, err case <-chanOpen: return respStream, nil } } // OpenPendingChannel attempts to open a channel between srcNode and destNode with the // passed channel funding parameters. If the passed context has a timeout, then // if the timeout is reached before the channel pending notification is // received, an error is returned. func (n *NetworkHarness) OpenPendingChannel(ctx context.Context, srcNode, destNode *HarnessNode, amt btcutil.Amount, pushAmt btcutil.Amount) (*lnrpc.PendingUpdate, error) { // Wait until srcNode and destNode have blockchain synced if err := srcNode.WaitForBlockchainSync(ctx); err != nil { return nil, fmt.Errorf("Unable to sync srcNode chain: %v", err) } if err := destNode.WaitForBlockchainSync(ctx); err != nil { return nil, fmt.Errorf("Unable to sync destNode chain: %v", err) } openReq := &lnrpc.OpenChannelRequest{ NodePubkey: destNode.PubKey[:], LocalFundingAmount: int64(amt), PushSat: int64(pushAmt), Private: false, } respStream, err := srcNode.OpenChannel(ctx, openReq) if err != nil { return nil, fmt.Errorf("unable to open channel between "+ "alice and bob: %v", err) } chanPending := make(chan *lnrpc.PendingUpdate) errChan := make(chan error) go func() { // Consume the "channel pending" update. This waits until the node // notifies us that the final message in the channel funding workflow // has been sent to the remote node. resp, err := respStream.Recv() if err != nil { errChan <- err return } pendingResp, ok := resp.Update.(*lnrpc.OpenStatusUpdate_ChanPending) if !ok { errChan <- fmt.Errorf("expected channel pending update, "+ "instead got %v", resp) return } chanPending <- pendingResp.ChanPending }() select { case <-ctx.Done(): return nil, fmt.Errorf("timeout reached before chan pending " + "update sent") case err := <-errChan: return nil, err case pendingChan := <-chanPending: return pendingChan, nil } } // WaitForChannelOpen waits for a notification that a channel is open by // consuming a message from the past open channel stream. If the passed context // has a timeout, then if the timeout is reached before the channel has been // opened, then an error is returned. func (n *NetworkHarness) WaitForChannelOpen(ctx context.Context, openChanStream lnrpc.Lightning_OpenChannelClient) (*lnrpc.ChannelPoint, error) { errChan := make(chan error) respChan := make(chan *lnrpc.ChannelPoint) go func() { resp, err := openChanStream.Recv() if err != nil { errChan <- fmt.Errorf("unable to read rpc resp: %v", err) return } fundingResp, ok := resp.Update.(*lnrpc.OpenStatusUpdate_ChanOpen) if !ok { errChan <- fmt.Errorf("expected channel open update, "+ "instead got %v", resp) return } respChan <- fundingResp.ChanOpen.ChannelPoint }() select { case <-ctx.Done(): return nil, fmt.Errorf("timeout reached while waiting for " + "channel open") case err := <-errChan: return nil, err case chanPoint := <-respChan: return chanPoint, nil } } // CloseChannel close channel attempts to close the channel indicated by the // passed channel point, initiated by the passed lnNode. If the passed context // has a timeout, then if the timeout is reached before the channel close is // pending, then an error is returned. func (n *NetworkHarness) CloseChannel(ctx context.Context, lnNode *HarnessNode, cp *lnrpc.ChannelPoint, force bool) (lnrpc.Lightning_CloseChannelClient, *chainhash.Hash, error) { // Create a channel outpoint that we can use to compare to channels // from the ListChannelsResponse. fundingTxID, err := chainhash.NewHash(cp.FundingTxid) if err != nil { return nil, nil, err } chanPoint := wire.OutPoint{ Hash: *fundingTxID, Index: cp.OutputIndex, } // We'll wait for *both* nodes to read the channel as active if we're // performing a cooperative channel closure. if !force { timeout := time.Second * 15 listReq := &lnrpc.ListChannelsRequest{} // We define two helper functions, one two locate a particular // channel, and the other to check if a channel is active or // not. filterChannel := func(node *HarnessNode, op wire.OutPoint) (*lnrpc.ActiveChannel, error) { listResp, err := node.ListChannels(ctx, listReq) if err != nil { return nil, err } for _, c := range listResp.Channels { if c.ChannelPoint == op.String() { return c, nil } } return nil, fmt.Errorf("unable to find channel") } activeChanPredicate := func(node *HarnessNode) func() bool { return func() bool { channel, err := filterChannel(node, chanPoint) if err != nil { } return channel.Active } } // Next, we'll fetch the target channel in order to get the // harness node that'll be receiving the channel close request. targetChan, err := filterChannel(lnNode, chanPoint) if err != nil { return nil, nil, err } receivingNode, err := n.LookUpNodeByPub(targetChan.RemotePubkey) if err != nil { return nil, nil, err } // Before proceeding, we'll ensure that the channel is active // for both nodes. err = WaitPredicate(activeChanPredicate(lnNode), timeout) if err != nil { return nil, nil, fmt.Errorf("channel of closing " + "node not active in time") } err = WaitPredicate(activeChanPredicate(receivingNode), timeout) if err != nil { return nil, nil, fmt.Errorf("channel of receiving " + "node not active in time") } } closeReq := &lnrpc.CloseChannelRequest{ ChannelPoint: cp, Force: force, } closeRespStream, err := lnNode.CloseChannel(ctx, closeReq) if err != nil { return nil, nil, fmt.Errorf("unable to close channel: %v", err) } errChan := make(chan error) fin := make(chan *chainhash.Hash) go func() { // Consume the "channel close" update in order to wait for the closing // transaction to be broadcast, then wait for the closing tx to be seen // within the network. closeResp, err := closeRespStream.Recv() if err != nil { errChan <- err return } pendingClose, ok := closeResp.Update.(*lnrpc.CloseStatusUpdate_ClosePending) if !ok { errChan <- fmt.Errorf("expected channel close update, "+ "instead got %v", pendingClose) return } closeTxid, err := chainhash.NewHash(pendingClose.ClosePending.Txid) if err != nil { errChan <- err return } if err := n.WaitForTxBroadcast(ctx, *closeTxid); err != nil { errChan <- err return } fin <- closeTxid }() // Wait until either the deadline for the context expires, an error // occurs, or the channel close update is received. select { case <-ctx.Done(): return nil, nil, fmt.Errorf("timeout reached before channel close " + "initiated") case err := <-errChan: return nil, nil, err case closeTxid := <-fin: return closeRespStream, closeTxid, nil } } // WaitForChannelClose waits for a notification from the passed channel close // stream that the node has deemed the channel has been fully closed. If the // passed context has a timeout, then if the timeout is reached before the // notification is received then an error is returned. func (n *NetworkHarness) WaitForChannelClose(ctx context.Context, closeChanStream lnrpc.Lightning_CloseChannelClient) (*chainhash.Hash, error) { errChan := make(chan error) updateChan := make(chan *lnrpc.CloseStatusUpdate_ChanClose) go func() { closeResp, err := closeChanStream.Recv() if err != nil { errChan <- err return } closeFin, ok := closeResp.Update.(*lnrpc.CloseStatusUpdate_ChanClose) if !ok { errChan <- fmt.Errorf("expected channel close update, "+ "instead got %v", closeFin) return } updateChan <- closeFin }() // Wait until either the deadline for the context expires, an error // occurs, or the channel close update is received. select { case <-ctx.Done(): return nil, fmt.Errorf("timeout reached before update sent") case err := <-errChan: return nil, err case update := <-updateChan: return chainhash.NewHash(update.ChanClose.ClosingTxid) } } // AssertChannelExists asserts that an active channel identified by // channelPoint is known to exist from the point-of-view of node.. func (n *NetworkHarness) AssertChannelExists(ctx context.Context, node *HarnessNode, chanPoint *wire.OutPoint) error { req := &lnrpc.ListChannelsRequest{} var predErr error pred := func() bool { resp, err := node.ListChannels(ctx, req) if err != nil { predErr = fmt.Errorf("unable fetch node's channels: %v", err) return false } for _, channel := range resp.Channels { if channel.ChannelPoint == chanPoint.String() { return true } } return false } if err := WaitPredicate(pred, time.Second*15); err != nil { return fmt.Errorf("channel not found: %v", predErr) } return nil } // WaitPredicate is a helper test function that will wait for a timeout period // of time until the passed predicate returns true. This function is helpful as // timing doesn't always line up well when running integration tests with // several running lnd nodes. This function gives callers a way to assert that // some property is upheld within a particular time frame. func WaitPredicate(pred func() bool, timeout time.Duration) error { exitTimer := time.After(timeout) for { select { case <-exitTimer: return fmt.Errorf("predicate not satisfied after time out") default: } if pred() { return nil } } } // DumpLogs reads the current logs generated by the passed node, and returns // the logs as a single string. This function is useful for examining the logs // of a particular node in the case of a test failure. // Logs from lightning node being generated with delay - you should // add time.Sleep() in order to get all logs. func (n *NetworkHarness) DumpLogs(node *HarnessNode) (string, error) { logFile := fmt.Sprintf("%v/simnet/lnd.log", node.cfg.LogDir) buf, err := ioutil.ReadFile(logFile) if err != nil { return "", err } return string(buf), nil } // SendCoins attempts to send amt satoshis from the internal mining node to the // targeted lightning node. func (n *NetworkHarness) SendCoins(ctx context.Context, amt btcutil.Amount, target *HarnessNode) error { balReq := &lnrpc.WalletBalanceRequest{} initialBalance, err := target.WalletBalance(ctx, balReq) if err != nil { return err } // First, obtain an address from the target lightning node, preferring // to receive a p2wkh address s.t the output can immediately be used as // an input to a funding transaction. addrReq := &lnrpc.NewAddressRequest{ Type: lnrpc.NewAddressRequest_WITNESS_PUBKEY_HASH, } resp, err := target.NewAddress(ctx, addrReq) if err != nil { return err } addr, err := btcutil.DecodeAddress(resp.Address, n.netParams) if err != nil { return err } addrScript, err := txscript.PayToAddrScript(addr) if err != nil { return err } // Generate a transaction which creates an output to the target // pkScript of the desired amount. output := &wire.TxOut{ PkScript: addrScript, Value: int64(amt), } if _, err := n.Miner.SendOutputs([]*wire.TxOut{output}, 30); err != nil { return err } // Finally, generate 6 new blocks to ensure the output gains a // sufficient number of confirmations. if _, err := n.Miner.Node.Generate(6); err != nil { return err } // Pause until the nodes current wallet balances reflects the amount // sent to it above. // TODO(roasbeef): factor out into helper func balanceTicker := time.Tick(time.Millisecond * 50) balanceTimeout := time.After(time.Second * 30) for { select { case <-balanceTicker: currentBal, err := target.WalletBalance(ctx, balReq) if err != nil { return err } if currentBal.ConfirmedBalance == initialBalance.ConfirmedBalance+int64(amt) { return nil } case <-balanceTimeout: return fmt.Errorf("balances not synced after deadline") } } }