Add ability to RBF a transaction with a single output

BTCPayServer.Tests/PlaywrightTester.cs

@@ -474,6 +474,7 @@ namespace BTCPayServer.Tests
                     goto retry;
                 }
             }
+            await Server.ExplorerNode.GenerateAsync(1);
             await Page.ReloadAsync();
             await Page.Locator("#CancelWizard").ClickAsync();
             return addressStr;
@@ -541,5 +542,23 @@ namespace BTCPayServer.Tests
             await page.BringToFrontAsync();
             return new SwitchDisposable(page, old, this, closeAfter);
         }
+
+        public async Task<SendWalletPMO> GoToWalletSend(WalletId walletId = null)
+        {
+            await GoToWallet(walletId, navPages: WalletsNavPages.Send);
+            return new(Page);
+        }
+
+        public class SendWalletPMO(IPage page)
+        {
+            public Task FillAddress(BitcoinAddress address) => page.FillAsync("[name='Outputs[0].DestinationAddress']",
+                address.ToString());
+
+            public Task SweepBalance() => page.ClickAsync("#SweepBalance");
+
+            public Task Sign() => page.ClickAsync("#SignTransaction");
+
+            public Task SetFeeRate(decimal val) => page.FillAsync("[name=\"FeeSatoshiPerByte\"]", val.ToString(CultureInfo.InvariantCulture));
+        }
     }
 }

BTCPayServer.Tests/WalletTests.cs

@@ -2,8 +2,6 @@
 using System.Linq;
 using System.Threading.Tasks;
 using BTCPayServer.Abstractions.Models;
-using BTCPayServer.Client;
-using BTCPayServer.Client.Models;
 using BTCPayServer.Views.Wallets;
 using NBitcoin;
 using Xunit;
@@ -87,6 +85,21 @@ public class WalletTests(ITestOutputHelper helper) : UnitTestBase(helper)
         // However, the new transaction should have copied the CPFP tag from the transaction it replaced, and have a RBF label as well.
         await AssertHasLabels(s, rbfTx, "CPFP");
         await AssertHasLabels(s, rbfTx, "RBF");
+
+        // Now, we sweep all the UTXOs to a single destination. This should be RBF-able. (Fee deducted on the lone UTXO)
+        await s.GoToWallet(navPages: WalletsNavPages.Send);
+        var send = await s.GoToWalletSend();
+        await send.FillAddress(new Key().PubKey.GetAddress(ScriptPubKeyType.Legacy, Network.RegTest));
+        await send.SweepBalance();
+        await send.SetFeeRate(20m);
+        await send.Sign();
+        await s.Page.ClickAsync("button[value=broadcast]");
+        // Now we RBF the sweep
+        await ClickBumpFee(s);
+        Assert.Equal("RBF", await s.Page.Locator("#BumpMethod").InnerTextAsync());
+        await s.ClickPagePrimary();
+        await s.Page.ClickAsync("#BroadcastTransaction");
+        await AssertHasLabels(s, "RBF");
     }
 
     private async Task CreateInvoices(PlaywrightTester tester)
@@ -107,13 +120,10 @@ public class WalletTests(ITestOutputHelper helper) : UnitTestBase(helper)
         await s.Page.ReloadAsync();
         await s.Page.Locator($"{TxRowSelector(txId)} .transaction-label[data-value=\"{label}\"]").WaitForAsync();
     }
-    private async Task AssertHasLabels(PlaywrightTester s, string label)
-    {
-        await s.Page.ReloadAsync();
-        await s.Page.Locator($".transaction-label[data-value=\"{label}\"]").First.WaitForAsync();
-    }
 
-    static string TxRowSelector(uint256 txId) => $".transaction-row[data-value=\"{txId}\"]";
+    private Task AssertHasLabels(PlaywrightTester s, string label) => AssertHasLabels(s, null, label);
+
+    static string TxRowSelector(uint256 txId) => txId is null ? ".transaction-row:first-of-type"  : $".transaction-row[data-value=\"{txId}\"]";
 
     private async Task SelectTransactions(PlaywrightTester s, params uint256[] txs)
     {
@@ -123,7 +133,7 @@ public class WalletTests(ITestOutputHelper helper) : UnitTestBase(helper)
         }
     }
 
-    private async Task ClickBumpFee(PlaywrightTester s, uint256 txId)
+    private async Task ClickBumpFee(PlaywrightTester s, uint256 txId = null)
     {
         await s.Page.ClickAsync($"{TxRowSelector(txId)} .bumpFee-btn");
     }

BTCPayServer/Controllers/UIWalletsController.cs

@@ -284,7 +284,6 @@ namespace BTCPayServer.Controllers
             model.RecommendedSatoshiPerByte =
                 recommendedFees.Where(option => option != null).ToList();
             model.FeeSatoshiPerByte ??= recommendedFees.Skip(1).FirstOrDefault()?.FeeRate;
-
             if (HttpContext.Request.Method != HttpMethods.Post)
             {
                 model.Command = null;
@@ -303,7 +302,7 @@ namespace BTCPayServer.Controllers
             var feeBumpUrl = Url.Action(nameof(WalletBumpFee), new { walletId, transactionId = bumpTarget.GetSingleTransactionId(), model.FeeSatoshiPerByte, model.BumpMethod, model.TransactionHashes, model.Outpoints })!;
             if (model.BumpMethod == "CPFP")
             {
-                var utxos = await explorer.GetUTXOsAsync(paymentMethod.AccountDerivation);
+                var utxos = await explorer.GetUTXOsAsync(paymentMethod.AccountDerivation, cancellationToken);
 
                 List<OutPoint> bumpableUTXOs = bumpTarget.GetMatchedOutpoints(utxos.GetUnspentUTXOs().Where(u => u.Confirmations == 0).Select(u => u.Outpoint));
                 if (bumpableUTXOs.Count == 0)
@@ -350,12 +349,16 @@ namespace BTCPayServer.Controllers
                 // RBF is only supported for a single tx
                 var tx = txs[bumpTarget.GetSingleTransactionId()!];
                 var changeOutput = tx.Outputs.FirstOrDefault(o => o.Feature == DerivationFeature.Change);
+                if (changeOutput is null &&
+                    tx is { Transaction: { Outputs: [{ ScriptPubKey: {} singleAddress }] }})
+                    changeOutput = new() { ScriptPubKey = singleAddress, Index = 0 };
                 if (tx.Inputs.Count != tx.Transaction?.Inputs.Count ||
                     changeOutput is null)
                 {
                     this.ModelState.AddModelError(nameof(model.BumpMethod), StringLocalizer["This transaction can't be RBF'd"]);
                     return View(nameof(WalletBumpFee), model);
                 }
+
                 IActionResult ChangeTooSmall(WalletBumpFeeViewModel vm, Money? missing)
                 {
                     if (missing is not null)
@@ -365,7 +368,14 @@ namespace BTCPayServer.Controllers
                     return View(nameof(WalletBumpFee), vm);
                 }
 
-                var bumpResult = bumpable[tx.TransactionId].ReplacementInfo!.CalculateBumpResult(targetFeeRate);
+                var bumpableTx = bumpable[tx.TransactionId].ReplacementInfo!;
+                if (targetFeeRate < bumpableTx.CalculateNewMinFeeRate())
+                {
+                    ModelState.AddModelError(nameof(model.FeeSatoshiPerByte), StringLocalizer["The selected fee rate is too small. The minimum is {0} sat/byte", bumpableTx.CalculateNewMinFeeRate().SatoshiPerByte]);
+                    return View(nameof(WalletBumpFee), model);
+                }
+
+                var bumpResult = bumpableTx.CalculateBumpResult(targetFeeRate);
                 var createPSBT = new CreatePSBTRequest()
                 {
                     RBF = true,
@@ -378,7 +388,12 @@ namespace BTCPayServer.Controllers
                     {
                         ExplicitFee = bumpResult.NewTxFee
                     },
-                    ExplicitChangeAddress = changeOutput.Address,
+                    ExplicitChangeAddress = changeOutput switch
+                    {
+                        { Address: {} addr } => PSBTDestination.Create(addr),
+                        { ScriptPubKey: {} scriptPubKey } => PSBTDestination.Create(scriptPubKey),
+                        _ => throw new InvalidOperationException("Invalid change output")
+                    },
                     Destinations = tx.Transaction.Outputs.AsIndexedOutputs()
                                         .Select(o => new CreatePSBTDestination()
                                         {
@@ -904,8 +919,7 @@ namespace BTCPayServer.Controllers
             {
                 try
                 {
-                    var result = await feeProvider.GetFeeRateAsync(
+                    var result = await feeProvider.GetFeeRateAsync((int)network.NBitcoinNetwork.Consensus.GetExpectedBlocksFor(time));
-                        (int)network.NBitcoinNetwork.Consensus.GetExpectedBlocksFor(time));
                     options.Add(new WalletSendModel.FeeRateOption()
                     {
                         Target = time,

BTCPayServer/HostedServices/TransactionLabelMarkerHostedService.cs

@@ -92,24 +92,20 @@ namespace BTCPayServer.HostedServices
                             {
                                 if (transactionEvent.NewTransactionEvent.Replacing is not null)
                                 {
-
                                     foreach (var replaced in transactionEvent.NewTransactionEvent.Replacing)
                                     {
                                         var replacedwoId = new WalletObjectId(wid,
                                               WalletObjectData.Types.Tx, replaced.ToString());
                                         var replacedo = await _walletRepository.GetWalletObject(replacedwoId);
                                         var replacedLinks = replacedo?.GetLinks().Where(t => t.type != WalletObjectData.Types.Tx) ?? [];
-                                        if (replacedLinks.Count() != 0)
+                                        var rbf = new WalletObjectId(wid, WalletObjectData.Types.RBF, "");
+                                        var label = WalletRepository.CreateLabel(rbf);
+                                        newObjs.Add(label.ObjectData);
+                                        links.Add(WalletRepository.NewWalletObjectLinkData(txWalletObject, label.Id));
+                                        links.Add(WalletRepository.NewWalletObjectLinkData(txWalletObject, rbf, new JObject()
                                         {
-                                            var rbf = new WalletObjectId(wid, WalletObjectData.Types.RBF, "");
+                                            ["txs"] = JArray.FromObject(new[] { replaced.ToString() })
-                                            var label = WalletRepository.CreateLabel(rbf);
+                                        }));
-                                            newObjs.Add(label.ObjectData);
-                                            links.Add(WalletRepository.NewWalletObjectLinkData(txWalletObject, label.Id));
-                                            links.Add(WalletRepository.NewWalletObjectLinkData(txWalletObject, rbf, new JObject()
-                                            {
-                                                ["txs"] = JArray.FromObject(new[] { replaced.ToString() })
-                                            }));
-                                        }
                                         foreach (var link in replacedLinks)
                                         {
                                             links.Add(WalletRepository.NewWalletObjectLinkData(new WalletObjectId(walletObjectDatas.Key, link.type, link.id), txWalletObject, link.linkdata));

BTCPayServer/Payments/Bitcoin/NBXplorerListener.cs

@@ -155,10 +155,7 @@ namespace BTCPayServer.Payments.Bitcoin
                                 if (evt.DerivationStrategy != null)
                                 {
                                     wallet.InvalidateCache(evt.DerivationStrategy);
-                                    var validOutputs = network.GetValidOutputs(evt).ToList();
+                                    foreach (var output in network.GetValidOutputs(evt))
-                                    if (!validOutputs.Any())
-                                        break;
-                                    foreach (var output in validOutputs)
                                     {
                                         if (!output.matchedOutput.Value.IsCompatible(network))
                                             continue;

BTCPayServer/Services/Fees/NBxplorerFeeProvider.cs

@@ -10,7 +10,7 @@ namespace BTCPayServer.Services.Fees
     {
         public async Task<FeeRate> GetFeeRateAsync(int blockTarget = 20)
         {
-                return (await ExplorerClient.GetFeeRateAsync(blockTarget).ConfigureAwait(false)).FeeRate;
+            return (await ExplorerClient.GetFeeRateAsync(blockTarget).ConfigureAwait(false)).FeeRate;
         }
     }
 }

BTCPayServer/Services/Wallets/BTCPayWallet.cs

@@ -338,9 +338,9 @@ namespace BTCPayServer.Services.Wallets
                         WHERE code = @code AND wallet_id=@walletId AND mempool IS TRUE AND replaced_by IS NULL AND blk_id IS NULL
                         GROUP BY code, tx_id
                     )
-                    SELECT tt.tx_id, u.raw, tt.input_count, tt.change_count, uu.unspent_count FROM unconfs u
+                    SELECT tt.tx_id, u.raw, tt.input_count, tt.change_count, COALESCE(uu.unspent_count, 0) FROM unconfs u
                     JOIN tracked_txs tt USING (code, tx_id)
-                    JOIN unspent_utxos uu USING (code, tx_id);
+                    LEFT JOIN unspent_utxos uu USING (code, tx_id);
                     """,
                     parameters: new
                     {
@@ -367,8 +367,11 @@ namespace BTCPayServer.Services.Wallets
                 {
                     continue;
                 }
-                if ((state.MempoolInfo?.FullRBF is true || tx.RBF) && tx.Inputs.Count == r.input_count &&
+
-                    r.change_count > 0)
+                var rbf = state.MempoolInfo?.FullRBF is true || Network.IsBTC || tx.RBF;
+                rbf &= tx.Inputs.Count == r.input_count;
+                rbf &= r.change_count > 0 || tx.Outputs.Count == 1;
+                if (rbf)
                 {
                     canRBF.Add(uint256.Parse(r.tx_id));
                 }

BTCPayServer/Views/UIWallets/WalletBumpFee.cshtml

@@ -67,18 +67,10 @@
 			<input type="hidden" asp-for="Outpoints[i]" />
 		}
 	}
-	@if (!ViewContext.ModelState.IsValid)
+    @if (!ViewContext.ModelState.IsValid)
-	{
+    {
-		<ul class="text-danger">
+        <div asp-validation-summary="All"></div>
-			@foreach (var errors in ViewData.ModelState.Where(pair => pair.Key == string.Empty && pair.Value.ValidationState == ModelValidationState.Invalid))
+    }
-			{
-				foreach (var error in errors.Value.Errors)
-				{
-					<li>@error.ErrorMessage</li>
-				}
-			}
-		</ul>
-	}
 	@if (Model.GetBumpTarget().GetSingleTransactionId() is { } txId)
 	{
 		<div class="list-group list-group-flush">

BTCPayServer/Views/UIWallets/WalletSend.cshtml

@@ -127,7 +127,7 @@
                     </div>
                     <div class="form-text crypto-info">
                         <span text-translate="true">Your available balance is</span>
-                        <button type="button" class="crypto-balance-link btn btn-link p-0 align-baseline">@Model.CurrentBalance</button> <span>@Model.CryptoCode</span>.
+                        <button id="SweepBalance" type="button" class="crypto-balance-link btn btn-link p-0 align-baseline">@Model.CurrentBalance</button> <span>@Model.CryptoCode</span>.
                         @if (Model.ImmatureBalance > 0)
                         {
                             <span><br>@StringLocalizer["Note: {0} are still immature and require additional confirmations.", $"{Model.ImmatureBalance} {Model.CryptoCode}"]</span>
@@ -205,7 +205,7 @@
                     <input asp-for="AlwaysIncludeNonWitnessUTXO" class="btcpay-toggle me-3"/>
                     <label asp-for="AlwaysIncludeNonWitnessUTXO" class="form-check-label"></label>
                 </div>
-                
+
                 @if (!string.IsNullOrEmpty(Model.PayJoinBIP21))
                 {
                     <div class="d-flex mb-3">