cnct: add invoice registry interface

Create an interface type to be able to mock the registry in unit tests.

contractcourt/chain_arbitrator.go

@@ -12,7 +12,6 @@ import (
 	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/input"
-	"github.com/lightningnetwork/lnd/invoices"
 	"github.com/lightningnetwork/lnd/lnwallet"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/sweep"
@@ -146,7 +145,7 @@ type ChainArbitratorConfig struct {
 
 	// Registry is the invoice database that is used by resolvers to lookup
 	// preimages and settle invoices.
-	Registry *invoices.InvoiceRegistry
+	Registry Registry
 
 	// NotifyClosedChannel is a function closure that the ChainArbitrator
 	// will use to notify the ChannelNotifier about a newly closed channel.

contractcourt/interfaces.go

@@ -0,0 +1,28 @@
+package contractcourt
+
+import (
+	"github.com/lightningnetwork/lnd/channeldb"
+	"github.com/lightningnetwork/lnd/invoices"
+	"github.com/lightningnetwork/lnd/lntypes"
+	"github.com/lightningnetwork/lnd/lnwire"
+)
+
+// Registry is an interface which represents the invoice registry.
+type Registry interface {
+	// LookupInvoice attempts to look up an invoice according to its 32
+	// byte payment hash. This method should also reutrn the min final CLTV
+	// delta for this invoice. We'll use this to ensure that the HTLC
+	// extended to us gives us enough time to settle as we prescribe.
+	LookupInvoice(lntypes.Hash) (channeldb.Invoice, uint32, error)
+
+	// NotifyExitHopHtlc attempts to mark an invoice as settled. If the
+	// invoice is a debug invoice, then this method is a noop as debug
+	// invoices are never fully settled. The return value describes how the
+	// htlc should be resolved. If the htlc cannot be resolved immediately,
+	// the resolution is sent on the passed in hodlChan later.
+	NotifyExitHopHtlc(payHash lntypes.Hash, paidAmount lnwire.MilliSatoshi,
+		hodlChan chan<- interface{}) (*invoices.HodlEvent, error)
+
+	// HodlUnsubscribeAll unsubscribes from all hodl events.
+	HodlUnsubscribeAll(subscriber chan<- interface{})
+}