Merge pull request #378 from carlaKC/383-cancelation

loopout: Add swap cancelation for swaps that cannot route off-chain

Author: carlaKC

client.go

@@ -142,6 +142,7 @@ func NewClient(dbDir string, cfg *ClientConfig) (*Client, func(), error) {
 		sweeper:           sweeper,
 		createExpiryTimer: config.CreateExpiryTimer,
 		loopOutMaxParts:   cfg.LoopOutMaxParts,
+		cancelSwap:        swapServerClient.CancelLoopOutSwap,
 	})
 
 	client := &Client{

client_test.go

@@ -100,6 +100,7 @@ func TestFailOffchain(t *testing.T) {
 	signalPrepaymentResult(
 		errors.New(lndclient.PaymentResultUnknownPaymentHash),
 	)
+	<-ctx.serverMock.cancelSwap
 	ctx.assertStatus(loopdb.StateFailOffchainPayments)
 
 	ctx.assertStoreFinished(loopdb.StateFailOffchainPayments)

executor.go

@@ -25,6 +25,8 @@ type executorConfig struct {
 	createExpiryTimer func(expiry time.Duration) <-chan time.Time
 
 	loopOutMaxParts uint32
+
+	cancelSwap func(ctx context.Context, details *outCancelDetails) error
 }
 
 // executor is responsible for executing swaps.
@@ -138,13 +140,17 @@ func (s *executor) run(mainCtx context.Context,
 			go func() {
 				defer s.wg.Done()
 
-				newSwap.execute(mainCtx, &executeConfig{
+				err := newSwap.execute(mainCtx, &executeConfig{
 					statusChan:      statusChan,
 					sweeper:         s.sweeper,
 					blockEpochChan:  queue.ChanOut(),
 					timerFactory:    s.executorConfig.createExpiryTimer,
 					loopOutMaxParts: s.executorConfig.loopOutMaxParts,
+					cancelSwap:      s.executorConfig.cancelSwap,
 				}, height)
+				if err != nil && err != context.Canceled {
+					log.Errorf("Execute error: %v", err)
+				}
 
 				select {
 				case swapDoneChan <- swapID:

loopdb/protocol_version.go

@@ -39,13 +39,17 @@ const (
 	// invoice so that the server can perform a multi-path probe.
 	ProtocolVersionMultiLoopIn ProtocolVersion = 6
 
+	// ProtocolVersionLoopOutCancel indicates that the client supports
+	// canceling loop out swaps.
+	ProtocolVersionLoopOutCancel = 7
+
 	// ProtocolVersionUnrecorded is set for swaps were created before we
 	// started saving protocol version with swaps.
 	ProtocolVersionUnrecorded ProtocolVersion = math.MaxUint32
 
 	// CurrentRPCProtocolVersion defines the version of the RPC protocol
 	// that is currently supported by the loop client.
-	CurrentRPCProtocolVersion = looprpc.ProtocolVersion_MULTI_LOOP_IN
+	CurrentRPCProtocolVersion = looprpc.ProtocolVersion_LOOP_OUT_CANCEL
 
 	// CurrentInternalProtocolVersion defines the RPC current protocol in
 	// the internal representation.
@@ -81,6 +85,9 @@ func (p ProtocolVersion) String() string {
 	case ProtocolVersionHtlcV2:
 		return "HTLC V2"
 
+	case ProtocolVersionLoopOutCancel:
+		return "Loop Out Cancel"
+
 	default:
 		return "Unknown"
 	}

loopdb/protocol_version_test.go

@@ -21,6 +21,7 @@ func TestProtocolVersionSanity(t *testing.T) {
 		ProtocolVersionUserExpiryLoopOut,
 		ProtocolVersionHtlcV2,
 		ProtocolVersionMultiLoopIn,
+		ProtocolVersionLoopOutCancel,
 	}
 
 	rpcVersions := [...]looprpc.ProtocolVersion{
@@ -31,6 +32,7 @@ func TestProtocolVersionSanity(t *testing.T) {
 		looprpc.ProtocolVersion_USER_EXPIRY_LOOP_OUT,
 		looprpc.ProtocolVersion_HTLC_V2,
 		looprpc.ProtocolVersion_MULTI_LOOP_IN,
+		looprpc.ProtocolVersion_LOOP_OUT_CANCEL,
 	}
 
 	require.Equal(t, len(versions), len(rpcVersions))

loopin_testcontext_test.go

@@ -39,6 +39,7 @@ func newLoopInTestContext(t *testing.T) *loopInTestContext {
 		sweeper:        &sweeper,
 		blockEpochChan: blockEpochChan,
 		timerFactory:   timerFactory,
+		cancelSwap:     server.CancelLoopOutSwap,
 	}
 
 	return &loopInTestContext{