Merge pull request #8426 from breez/expose-closing-tx

Expose closing tx in waiting_close_channels

cmd/lncli/commands.go

@@ -1445,15 +1445,25 @@ var pendingChannelsCommand = cli.Command{
 	Name:     "pendingchannels",
 	Category: "Channels",
 	Usage:    "Display information pertaining to pending channels.",
-	Action:   actionDecorator(pendingChannels),
+	Flags: []cli.Flag{
+		cli.BoolFlag{
+			Name: "include_raw_tx",
+			Usage: "include the raw transaction hex for " +
+				"waiting_close_channels.",
+		},
+	},
+	Action: actionDecorator(pendingChannels),
 }
 
 func pendingChannels(ctx *cli.Context) error {
 	ctxc := getContext()
 	client, cleanUp := getClient(ctx)
 	defer cleanUp()
 
-	req := &lnrpc.PendingChannelsRequest{}
+	includeRawTx := ctx.Bool("include_raw_tx")
+	req := &lnrpc.PendingChannelsRequest{
+		IncludeRawTx: includeRawTx,
+	}
 	resp, err := client.PendingChannels(ctxc, req)
 	if err != nil {
 		return err

docs/release-notes/release-notes-0.18.0.md

@@ -187,6 +187,10 @@
   [MinConf](https://github.com/lightningnetwork/lnd/pull/8097)(minimum number
   of confirmations) has been added to the `WalletBalance` RPC call.
 
+* `PendingChannels` now optionally returns the 
+  [raw hex of the closing tx](https://github.com/lightningnetwork/lnd/pull/8426)
+  in `waiting_close_channels`.
+
 ## lncli Updates
 
 * [Documented all available lncli commands](https://github.com/lightningnetwork/lnd/pull/8181).
@@ -202,6 +206,10 @@
 * [Use the default LND value in the buildroute rpc command for the
   final cltv delta](https://github.com/lightningnetwork/lnd/pull/8387).
 
+* `pendingchannels` now optionally returns the 
+  [raw hex of the closing tx](https://github.com/lightningnetwork/lnd/pull/8426)
+  in `waiting_close_channels`.
+
 ## Code Health
 
 * [Remove Litecoin code](https://github.com/lightningnetwork/lnd/pull/7867).
@@ -287,6 +295,7 @@
 * Carla Kirk-Cohen
 * Elle Mouton
 * ErikEk
+* Jesse de Wit
 * Keagan McClelland
 * Marcos Fernandez Perez
 * Matt Morehouse

itest/lnd_channel_force_close_test.go

@@ -2,6 +2,7 @@ package itest
 
 import (
 	"bytes"
+	"encoding/hex"
 	"fmt"
 	"testing"
 
@@ -141,7 +142,24 @@ func testCommitmentTransactionDeadline(ht *lntest.HarnessTest) {
 		// Now that the channel has been force closed, it should show
 		// up in the PendingChannels RPC under the waiting close
 		// section.
-		ht.AssertChannelWaitingClose(alice, chanPoint)
+		waitingClose := ht.AssertChannelWaitingClose(alice, chanPoint)
+
+		// The waiting close channel closing tx hex should be set and
+		// be valid.
+		require.NotEmpty(ht, waitingClose.ClosingTxHex)
+		rawTxBytes, err := hex.DecodeString(waitingClose.ClosingTxHex)
+		require.NoError(
+			ht, err,
+			"waiting close channel closingTxHex invalid hex",
+		)
+		rawTx := &wire.MsgTx{}
+		err = rawTx.Deserialize(bytes.NewReader(rawTxBytes))
+		require.NoError(
+			ht, err, "waiting close channel ClosingTxHex invalid",
+		)
+		require.Equal(
+			ht, waitingClose.ClosingTxid, rawTx.TxHash().String(),
+		)
 
 		// We should see Alice's force closing tx in the mempool.
 		expectedNumTxes := 1

lnrpc/lightning.proto

@@ -2636,6 +2636,9 @@ message PendingHTLC {
 }
 
 message PendingChannelsRequest {
+    // Indicates whether to include the raw transaction hex for
+    // waiting_close_channels.
+    bool include_raw_tx = 1;
 }
 message PendingChannelsResponse {
     message PendingChannel {
@@ -2733,6 +2736,10 @@ message PendingChannelsResponse {
 
         // The transaction id of the closing transaction
         string closing_txid = 4;
+
+        // The raw hex encoded bytes of the closing transaction. Included if
+        // include_raw_tx in the request is true.
+        string closing_tx_hex = 5;
     }
 
     message Commitments {

lnrpc/lightning.swagger.json

@@ -582,6 +582,15 @@
             }
           }
         },
+        "parameters": [
+          {
+            "name": "include_raw_tx",
+            "description": "Indicates whether to include the raw transaction hex for\nwaiting_close_channels.",
+            "in": "query",
+            "required": false,
+            "type": "boolean"
+          }
+        ],
         "tags": [
           "Lightning"
         ]
@@ -3140,6 +3149,10 @@
         "closing_txid": {
           "type": "string",
           "title": "The transaction id of the closing transaction"
+        },
+        "closing_tx_hex": {
+          "type": "string",
+          "description": "The raw hex encoded bytes of the closing transaction. Included if\ninclude_raw_tx in the request is true."
         }
       }
     },

lntest/rpc/lnd.go

@@ -131,7 +131,9 @@ func (h *HarnessRPC) PendingChannels() *lnrpc.PendingChannelsResponse {
 	ctxt, cancel := context.WithTimeout(h.runCtx, DefaultTimeout)
 	defer cancel()
 
-	pendingChansRequest := &lnrpc.PendingChannelsRequest{}
+	pendingChansRequest := &lnrpc.PendingChannelsRequest{
+		IncludeRawTx: true,
+	}
 	resp, err := h.LN.PendingChannels(ctxt, pendingChansRequest)
 
 	// TODO(yy): We may get a `unable to find arbitrator` error from the

rpcserver.go

@@ -3718,8 +3718,8 @@ func (r *rpcServer) fetchPendingForceCloseChannels() (pendingForceClose,
 // fetchWaitingCloseChannels queries the database for a list of channels
 // that have their closing transactions broadcast but not confirmed yet.
 // The returned result is used in the response of the PendingChannels RPC.
-func (r *rpcServer) fetchWaitingCloseChannels() (waitingCloseChannels,
-	int64, error) {
+func (r *rpcServer) fetchWaitingCloseChannels(
+	includeRawTx bool) (waitingCloseChannels, int64, error) {
 
 	// We'll also fetch all channels that are open, but have had their
 	// commitment broadcasted, meaning they are waiting for the closing
@@ -3734,43 +3734,42 @@ func (r *rpcServer) fetchWaitingCloseChannels() (waitingCloseChannels,
 	result := make(waitingCloseChannels, 0)
 	limboBalance := int64(0)
 
-	// getClosingTx is a helper closure that tries to find the closing txid
-	// of a given waiting close channel. Notice that if the remote closes
-	// the channel, we may not have the closing txid.
-	getClosingTx := func(c *channeldb.OpenChannel) (string, error) {
+	// getClosingTx is a helper closure that tries to find the closing tx of
+	// a given waiting close channel. Notice that if the remote closes the
+	// channel, we may not have the closing tx.
+	getClosingTx := func(c *channeldb.OpenChannel) (*wire.MsgTx, error) {
 		var (
 			tx  *wire.MsgTx
 			err error
 		)
 
-		// First, we try to locate the force closing txid. If not
-		// found, we will then try to find its coop closing txid.
+		// First, we try to locate the force closing tx. If not found,
+		// we will then try to find its coop closing tx.
 		tx, err = c.BroadcastedCommitment()
 		if err == nil {
-			return tx.TxHash().String(), nil
+			return tx, nil
 		}
 
 		// If the error returned is not ErrNoCloseTx, something
 		// unexpected happened and we will return the error.
 		if err != channeldb.ErrNoCloseTx {
-			return "", err
+			return nil, err
 		}
 
-		// Otherwise, we continue to locate its coop closing txid.
+		// Otherwise, we continue to locate its coop closing tx.
 		tx, err = c.BroadcastedCooperative()
 		if err == nil {
-			return tx.TxHash().String(), nil
+			return tx, nil
 		}
 
 		// Return the error if it's not ErrNoCloseTx.
 		if err != channeldb.ErrNoCloseTx {
-			return "", err
+			return nil, err
 		}
 
-		// Otherwise return an empty txid. This can happen if the
-		// remote broadcast the closing txid and we haven't recorded it
-		// yet.
-		return "", nil
+		// Otherwise return an empty tx. This can happen if the remote
+		// broadcast the closing tx and we haven't recorded it yet.
+		return nil, nil
 	}
 
 	for _, waitingClose := range channels {
@@ -3830,12 +3829,12 @@ func (r *rpcServer) fetchWaitingCloseChannels() (waitingCloseChannels,
 			return nil, 0, err
 		}
 
-		// Get the closing txid.
-		// NOTE: the closing txid could be empty here if it's the
-		// remote broadcasted the closing tx.
-		closingTxid, err := getClosingTx(waitingClose)
+		// Get the closing tx.
+		// NOTE: the closing tx could be nil here if it's the remote
+		// that broadcasted the closing tx.
+		closingTx, err := getClosingTx(waitingClose)
 		if err != nil {
-			rpcsLog.Errorf("unable to find closing txid for "+
+			rpcsLog.Errorf("unable to find closing tx for "+
 				"channel:%s, %v",
 				waitingClose.ShortChannelID, err)
 			return nil, 0, err
@@ -3857,11 +3856,27 @@ func (r *rpcServer) fetchWaitingCloseChannels() (waitingCloseChannels,
 			Memo:                  string(waitingClose.Memo),
 		}
 
+		var closingTxid, closingTxHex string
+		if closingTx != nil {
+			closingTxid = closingTx.TxHash().String()
+			if includeRawTx {
+				var txBuf bytes.Buffer
+				err = closingTx.Serialize(&txBuf)
+				if err != nil {
+					return nil, 0, fmt.Errorf("failed to "+
+						"serialize closing transaction"+
+						": %w", err)
+				}
+				closingTxHex = hex.EncodeToString(txBuf.Bytes())
+			}
+		}
+
 		waitingCloseResp := &lnrpc.PendingChannelsResponse_WaitingCloseChannel{
 			Channel:      channel,
 			LimboBalance: channel.LocalBalance,
 			Commitments:  &commitments,
 			ClosingTxid:  closingTxid,
+			ClosingTxHex: closingTxHex,
 		}
 
 		// A close tx has been broadcasted, all our balance will be in
@@ -3904,7 +3919,9 @@ func (r *rpcServer) PendingChannels(ctx context.Context,
 	// Third, we fetch all channels that are open, but have had their
 	// commitment broadcasted, meaning they are waiting for the closing
 	// transaction to confirm.
-	waitingCloseChannels, limbo, err := r.fetchWaitingCloseChannels()
+	waitingCloseChannels, limbo, err := r.fetchWaitingCloseChannels(
+		in.IncludeRawTx,
+	)
 	if err != nil {
 		return nil, err
 	}