lncfg/wtclient: adds watchtower client CLI configuration

lncfg/wtclient.go

@@ -0,0 +1,65 @@
+package lncfg
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/lightningnetwork/lnd/lnwire"
+)
+
+// WtClient holds the configuration options for the daemon's watchtower client.
+type WtClient struct {
+	// PrivateTowerURIs specifies the lightning URIs of the towers the
+	// watchtower client should send new backups to.
+	PrivateTowerURIs []string `long:"private-tower-uris" description:"Specifies the URIs of private watchtowers to use in backing up revoked states. URIs must be of the form <pubkey>@<addr>. Only 1 URI is supported at this time, if none are provided the tower will not be enabled."`
+
+	// PrivateTowers is the list of towers parsed from the URIs provided in
+	// PrivateTowerURIs.
+	PrivateTowers []*lnwire.NetAddress
+
+	// SweepFeeRate specifies the fee rate in sat/byte to be used when
+	// constructing justice transactions sent to the tower.
+	SweepFeeRate uint64 `long:"sweep-fee-rate" description:"Specifies the fee rate in sat/byte to be used when constructing justice transactions sent to the watchtower."`
+}
+
+// Validate asserts that at most 1 private watchtower is requested.
+//
+// NOTE: Part of the Validator interface.
+func (c *WtClient) Validate() error {
+	if len(c.PrivateTowerURIs) > 1 {
+		return fmt.Errorf("at most 1 private watchtower is supported, "+
+			"found %d", len(c.PrivateTowerURIs))
+	}
+
+	return nil
+}
+
+// IsActive returns true if the watchtower client should be active.
+func (c *WtClient) IsActive() bool {
+	return len(c.PrivateTowerURIs) > 0
+}
+
+// ParsePrivateTowers parses any private tower URIs held PrivateTowerURIs. The
+// value of port should be the default port to use when a URI does not have one.
+func (c *WtClient) ParsePrivateTowers(port int, resolver TCPResolver) error {
+	towers := make([]*lnwire.NetAddress, 0, len(c.PrivateTowerURIs))
+	for _, uri := range c.PrivateTowerURIs {
+		addr, err := ParseLNAddressString(
+			uri, strconv.Itoa(port), resolver,
+		)
+		if err != nil {
+			return fmt.Errorf("unable to parse private "+
+				"watchtower address: %v", err)
+		}
+
+		towers = append(towers, addr)
+	}
+
+	c.PrivateTowers = towers
+
+	return nil
+}
+
+// Compile-time constraint to ensure WtClient implements the Validator
+// interface.
+var _ Validator = (*WtClient)(nil)