Merge pull request #9390 from NishantBansal2003/append-channel

Enhance `lncli` listchannels command with the chan_id and short_chan_id (human readable format)

cmd/commands/commands.go

@@ -21,6 +21,7 @@ import (
 	"github.com/jessevdk/go-flags"
 	"github.com/lightningnetwork/lnd"
 	"github.com/lightningnetwork/lnd/lnrpc"
+	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/routing"
 	"github.com/lightningnetwork/lnd/routing/route"
 	"github.com/lightningnetwork/lnd/signal"
@@ -50,6 +51,14 @@ var (
 	customDataPattern = regexp.MustCompile(
 		`"custom_channel_data":\s*"([0-9a-f]+)"`,
 	)
+
+	chanIDPattern = regexp.MustCompile(
+		`"chan_id":\s*"(\d+)"`,
+	)
+
+	channelPointPattern = regexp.MustCompile(
+		`"channel_point":\s*"([0-9a-fA-F]+:[0-9]+)"`,
+	)
 )
 
 // replaceCustomData replaces the custom channel data hex string with the
@@ -86,6 +95,96 @@ func replaceCustomData(jsonBytes []byte) []byte {
 	return buf.Bytes()
 }
 
+// replaceAndAppendScid replaces the chan_id with scid and appends the human
+// readable string representation of scid.
+func replaceAndAppendScid(jsonBytes []byte) []byte {
+	// If there's nothing to replace, return the original JSON.
+	if !chanIDPattern.Match(jsonBytes) {
+		return jsonBytes
+	}
+
+	replacedBytes := chanIDPattern.ReplaceAllFunc(
+		jsonBytes, func(match []byte) []byte {
+			// Extract the captured scid group from the match.
+			chanID := chanIDPattern.FindStringSubmatch(
+				string(match),
+			)[1]
+
+			scid, err := strconv.ParseUint(chanID, 10, 64)
+			if err != nil {
+				return match
+			}
+
+			// Format a new JSON field for the scid (chan_id),
+			// including both its numeric representation and its
+			// string representation (scid_str).
+			scidStr := lnwire.NewShortChanIDFromInt(scid).
+				AltString()
+			updatedField := fmt.Sprintf(
+				`"scid": "%d", "scid_str": "%s"`, scid, scidStr,
+			)
+
+			// Replace the entire match with the new structure.
+			return []byte(updatedField)
+		},
+	)
+
+	var buf bytes.Buffer
+	err := json.Indent(&buf, replacedBytes, "", "    ")
+	if err != nil {
+		// If we can't indent the JSON, it likely means the replacement
+		// data wasn't correct, so we return the original JSON.
+		return jsonBytes
+	}
+
+	return buf.Bytes()
+}
+
+// appendChanID appends the chan_id which is computed using the outpoint
+// of the funding transaction (the txid, and output index).
+func appendChanID(jsonBytes []byte) []byte {
+	// If there's nothing to replace, return the original JSON.
+	if !channelPointPattern.Match(jsonBytes) {
+		return jsonBytes
+	}
+
+	replacedBytes := channelPointPattern.ReplaceAllFunc(
+		jsonBytes, func(match []byte) []byte {
+			chanPoint := channelPointPattern.FindStringSubmatch(
+				string(match),
+			)[1]
+
+			chanOutpoint, err := wire.NewOutPointFromString(
+				chanPoint,
+			)
+			if err != nil {
+				return match
+			}
+
+			// Format a new JSON field computed from the
+			// channel_point (chan_id).
+			chanID := lnwire.NewChanIDFromOutPoint(*chanOutpoint)
+			updatedField := fmt.Sprintf(
+				`"channel_point": "%s", "chan_id": "%s"`,
+				chanPoint, chanID.String(),
+			)
+
+			// Replace the entire match with the new structure.
+			return []byte(updatedField)
+		},
+	)
+
+	var buf bytes.Buffer
+	err := json.Indent(&buf, replacedBytes, "", "    ")
+	if err != nil {
+		// If we can't indent the JSON, it likely means the replacement
+		// data wasn't correct, so we return the original JSON.
+		return jsonBytes
+	}
+
+	return buf.Bytes()
+}
+
 func getContext() context.Context {
 	shutdownInterceptor, err := signal.Intercept()
 	if err != nil {
@@ -120,8 +219,15 @@ func printRespJSON(resp proto.Message) {
 		return
 	}
 
+	// Replace custom_channel_data in the JSON.
 	jsonBytesReplaced := replaceCustomData(jsonBytes)
 
+	// Replace chan_id with scid, and append scid_str and scid fields.
+	jsonBytesReplaced = replaceAndAppendScid(jsonBytesReplaced)
+
+	// Append the chan_id field to the JSON.
+	jsonBytesReplaced = appendChanID(jsonBytesReplaced)
+
 	fmt.Printf("%s\n", jsonBytesReplaced)
 }
 

cmd/commands/commands_test.go

@@ -127,10 +127,9 @@ func TestReplaceCustomData(t *testing.T) {
 	t.Parallel()
 
 	testCases := []struct {
-		name        string
-		data        string
-		replaceData string
-		expected    string
+		name     string
+		data     string
+		expected string
 	}{
 		{
 			name:     "no replacement necessary",
@@ -139,10 +138,10 @@ func TestReplaceCustomData(t *testing.T) {
 		},
 		{
 			name: "valid json with replacement",
-			data: "{\"foo\":\"bar\",\"custom_channel_data\":\"" +
+			data: `{"foo":"bar","custom_channel_data":"` +
 				hex.EncodeToString([]byte(
-					"{\"bar\":\"baz\"}",
-				)) + "\"}",
+					`{"bar":"baz"}`,
+				)) + `"}`,
 			expected: `{
     "foo": "bar",
     "custom_channel_data": {
@@ -152,10 +151,10 @@ func TestReplaceCustomData(t *testing.T) {
 		},
 		{
 			name: "valid json with replacement and space",
-			data: "{\"foo\":\"bar\",\"custom_channel_data\": \"" +
+			data: `{"foo":"bar","custom_channel_data": "` +
 				hex.EncodeToString([]byte(
-					"{\"bar\":\"baz\"}",
-				)) + "\"}",
+					`{"bar":"baz"}`,
+				)) + `"}`,
 			expected: `{
     "foo": "bar",
     "custom_channel_data": {
@@ -178,9 +177,11 @@ func TestReplaceCustomData(t *testing.T) {
 				"\"custom_channel_data\":\"a\"",
 		},
 		{
-			name:     "valid json, invalid hex, just formatted",
-			data:     "{\"custom_channel_data\":\"f\"}",
-			expected: "{\n    \"custom_channel_data\": \"f\"\n}",
+			name: "valid json, invalid hex, just formatted",
+			data: `{"custom_channel_data":"f"}`,
+			expected: `{
+    "custom_channel_data": "f"
+}`,
 		},
 	}
 
@@ -191,3 +192,139 @@ func TestReplaceCustomData(t *testing.T) {
 		})
 	}
 }
+
+// TestReplaceAndAppendScid tests whether chan_id is replaced with scid and
+// scid_str in the JSON console output.
+func TestReplaceAndAppendScid(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name     string
+		data     string
+		expected string
+	}{
+		{
+			name:     "no replacement necessary",
+			data:     "foo",
+			expected: "foo",
+		},
+		{
+			name: "valid json with replacement",
+			data: `{"foo":"bar","chan_id":"829031767408640"}`,
+			expected: `{
+    "foo": "bar",
+    "scid": "829031767408640",
+    "scid_str": "754x1x0"
+}`,
+		},
+		{
+			name: "valid json with replacement and space",
+			data: `{"foo":"bar","chan_id": "829031767408640"}`,
+			expected: `{
+    "foo": "bar",
+    "scid": "829031767408640",
+    "scid_str": "754x1x0"
+}`,
+		},
+		{
+			name: "doesn't match pattern, returned identical",
+			data: "this ain't even json, and no chan_id " +
+				"either",
+			expected: "this ain't even json, and no chan_id " +
+				"either",
+		},
+		{
+			name: "invalid json",
+			data: "this ain't json, " +
+				"\"chan_id\":\"18446744073709551616\"",
+			expected: "this ain't json, " +
+				"\"chan_id\":\"18446744073709551616\"",
+		},
+		{
+			name: "valid json, invalid uint, just formatted",
+			data: `{"chan_id":"18446744073709551616"}`,
+			expected: `{
+    "chan_id": "18446744073709551616"
+}`,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result := replaceAndAppendScid([]byte(tc.data))
+			require.Equal(t, tc.expected, string(result))
+		})
+	}
+}
+
+// TestAppendChanID tests whether chan_id (BOLT02) is appended
+// to the JSON console output.
+func TestAppendChanID(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name     string
+		data     string
+		expected string
+	}{
+		{
+			name:     "no amendment necessary",
+			data:     "foo",
+			expected: "foo",
+		},
+		{
+			name: "valid json with amendment",
+			data: `{"foo":"bar","channel_point":"6ab312e3b744e` +
+				`1b80a33a6541697df88766515c31c08e839bf11dc` +
+				`9fcc036a19:0"}`,
+			expected: `{
+    "foo": "bar",
+    "channel_point": "6ab312e3b744e1b80a33a6541697df88766515c31c` +
+				`08e839bf11dc9fcc036a19:0",
+    "chan_id": "196a03cc9fdc11bf39e8081cc315657688df971654a` +
+				`6330ab8e144b7e312b36a"
+}`,
+		},
+		{
+			name: "valid json with amendment and space",
+			data: `{"foo":"bar","channel_point": "6ab312e3b744e` +
+				`1b80a33a6541697df88766515c31c08e839bf11dc` +
+				`9fcc036a19:0"}`,
+			expected: `{
+    "foo": "bar",
+    "channel_point": "6ab312e3b744e1b80a33a6541697df88766515c31c` +
+				`08e839bf11dc9fcc036a19:0",
+    "chan_id": "196a03cc9fdc11bf39e8081cc315657688df971654a` +
+				`6330ab8e144b7e312b36a"
+}`,
+		},
+		{
+			name: "doesn't match pattern, returned identical",
+			data: "this ain't even json, and no channel_point " +
+				"either",
+			expected: "this ain't even json, and no channel_point" +
+				" either",
+		},
+		{
+			name: "invalid json",
+			data: "this ain't json, " +
+				"\"channel_point\":\"f:0\"",
+			expected: "this ain't json, " +
+				"\"channel_point\":\"f:0\"",
+		},
+		{
+			name: "valid json with invalid outpoint, formatted",
+			data: `{"channel_point":"f:0"}`,
+			expected: `{
+    "channel_point": "f:0"
+}`,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			result := appendChanID([]byte(tc.data))
+			require.Equal(t, tc.expected, string(result))
+		})
+	}
+}

docs/release-notes/release-notes-0.19.0.md

@@ -111,6 +111,12 @@
   now update the channel policy if the edge was not found in the graph
   database if the `create_missing_edge` flag is set.
 
+* [Enhance](https://github.com/lightningnetwork/lnd/pull/9390) the
+  `lncli listchannels` output by adding the human readable short
+  channel id and the channel id defined in BOLT02. Moreover change
+  the misnomer of `chan_id` which was describing the short channel
+  id to `scid` to represent what it really is.
+
 # Improvements
 ## Functional Updates
 
@@ -282,6 +288,7 @@ The underlying functionality between those two options remain the same.
 * hieblmi
 * Jesse de Wit
 * Keagan McClelland
+* Nishant Bansal
 * Oliver Gugger
 * Pins
 * Viktor Tigerström

lnwire/short_channel_id.go

@@ -56,6 +56,12 @@ func (c ShortChannelID) String() string {
 	return fmt.Sprintf("%d:%d:%d", c.BlockHeight, c.TxIndex, c.TxPosition)
 }
 
+// AltString generates a human-readable representation of the channel ID
+// with 'x' as a separator.
+func (c ShortChannelID) AltString() string {
+	return fmt.Sprintf("%dx%dx%d", c.BlockHeight, c.TxIndex, c.TxPosition)
+}
+
 // Record returns a TLV record that can be used to encode/decode a
 // ShortChannelID to/from a TLV stream.
 func (c *ShortChannelID) Record() tlv.Record {