localchans: recreate missing edge if not found

channeldb/graph.go

@@ -1023,6 +1023,10 @@ func (c *ChannelGraph) AddChannelEdge(edge *models.ChannelEdgeInfo,
 	}
 
 	for _, f := range op {
+		if f == nil {
+			return fmt.Errorf("nil scheduler option was used")
+		}
+
 		f(r)
 	}
 

cmd/commands/commands.go

@@ -2359,6 +2359,21 @@ var updateChannelPolicyCommand = cli.Command{
 				"channels will be updated. Takes the form of " +
 				"txid:output_index",
 		},
+		cli.BoolFlag{
+			Name: "create_missing_edge",
+			Usage: "Under unknown circumstances a channel can " +
+				"exist with a missing edge in the graph " +
+				"database. This can cause an 'edge not " +
+				"found' error when calling `getchaninfo` " +
+				"and/or cause the default channel policy to " +
+				"be used during forwards. Setting this flag " +
+				"will recreate the edge if not found, " +
+				"allowing updating this channel policy and " +
+				"fixing the missing edge problem for this " +
+				"channel permanently. For fields not set in " +
+				"this command, the default policy will be " +
+				"created.",
+		},
 	},
 	Action: actionDecorator(updateChannelPolicy),
 }
@@ -2518,11 +2533,14 @@ func updateChannelPolicy(ctx *cli.Context) error {
 		}
 	}
 
+	createMissingEdge := ctx.Bool("create_missing_edge")
+
 	req := &lnrpc.PolicyUpdateRequest{
-		BaseFeeMsat:   baseFee,
-		TimeLockDelta: uint32(timeLockDelta),
-		MaxHtlcMsat:   ctx.Uint64("max_htlc_msat"),
-		InboundFee:    inboundFee,
+		BaseFeeMsat:       baseFee,
+		TimeLockDelta:     uint32(timeLockDelta),
+		MaxHtlcMsat:       ctx.Uint64("max_htlc_msat"),
+		InboundFee:        inboundFee,
+		CreateMissingEdge: createMissingEdge,
 	}
 
 	if ctx.IsSet("min_htlc_msat") {

docs/release-notes/release-notes-0.18.4.md

@@ -71,6 +71,10 @@ types](https://github.com/lightningnetwork/lnd/pull/8960).
 
 ## lncli Additions
 
+* [`updatechanpolicy`](https://github.com/lightningnetwork/lnd/pull/8805) will
+  now update the channel policy if the edge was not found in the graph
+  database if the `create_missing_edge` flag is set.
+
 # Improvements
 ## Functional Updates
 ## RPC Updates

lnrpc/lightning.proto

@@ -4558,6 +4558,15 @@ message PolicyUpdateRequest {
     // Optional inbound fee. If unset, the previously set value will be
     // retained [EXPERIMENTAL].
     InboundFee inbound_fee = 10;
+
+    // Under unknown circumstances a channel can exist with a missing edge in
+    // the graph database. This can cause an 'edge not found' error when calling
+    // `getchaninfo` and/or cause the default channel policy to be used during
+    // forwards. Setting this flag will recreate the edge if not found, allowing
+    // updating this channel policy and fixing the missing edge problem for this
+    // channel permanently. For fields not set in this command, the default
+    // policy will be created.
+    bool create_missing_edge = 11;
 }
 
 enum UpdateFailure {

lnrpc/lightning.swagger.json

@@ -6751,6 +6751,10 @@
         "inbound_fee": {
           "$ref": "#/definitions/lnrpcInboundFee",
           "description": "Optional inbound fee. If unset, the previously set value will be\nretained [EXPERIMENTAL]."
+        },
+        "create_missing_edge": {
+          "type": "boolean",
+          "description": "Under unknown circumstances a channel can exist with a missing edge in\nthe graph database. This can cause an 'edge not found' error when calling\n`getchaninfo` and/or cause the default channel policy to be used during\nforwards. Setting this flag will recreate the edge if not found, allowing\nupdating this channel policy and fixing the missing edge problem for this\nchannel permanently. For fields not set in this command, the default\npolicy will be created."
         }
       }
     },

log.go

@@ -46,6 +46,7 @@ import (
 	"github.com/lightningnetwork/lnd/peernotifier"
 	"github.com/lightningnetwork/lnd/routing"
 	"github.com/lightningnetwork/lnd/routing/blindedpath"
+	"github.com/lightningnetwork/lnd/routing/localchans"
 	"github.com/lightningnetwork/lnd/rpcperms"
 	"github.com/lightningnetwork/lnd/signal"
 	"github.com/lightningnetwork/lnd/sweep"
@@ -172,6 +173,7 @@ func SetupLoggers(root *build.SubLoggerManager, interceptor signal.Interceptor)
 	AddSubLogger(root, "CHFD", interceptor, chanfunding.UseLogger)
 	AddSubLogger(root, "PEER", interceptor, peer.UseLogger)
 	AddSubLogger(root, "CHCL", interceptor, chancloser.UseLogger)
+	AddSubLogger(root, "LCHN", interceptor, localchans.UseLogger)
 
 	AddSubLogger(root, routing.Subsystem, interceptor, routing.UseLogger)
 	AddSubLogger(root, routerrpc.Subsystem, interceptor, routerrpc.UseLogger)

routing/localchans/log.go

@@ -0,0 +1,31 @@
+package localchans
+
+import (
+	"github.com/btcsuite/btclog/v2"
+	"github.com/lightningnetwork/lnd/build"
+)
+
+// log is a logger that is initialized with no output filters.  This means the
+// package will not perform any logging by default until the caller requests
+// it.
+var log btclog.Logger
+
+const Subsystem = "LCHN"
+
+// The default amount of logging is none.
+func init() {
+	UseLogger(build.NewSubLogger(Subsystem, nil))
+}
+
+// DisableLog disables all library log output.  Logging output is disabled by
+// default until UseLogger is called.
+func DisableLog() {
+	UseLogger(btclog.Disabled)
+}
+
+// UseLogger uses a specified Logger to output package logging info.  This
+// should be used in preference to SetLogWriter if the caller is also using
+// btclog.
+func UseLogger(logger btclog.Logger) {
+	log = logger
+}