Form Builder (#4137)

* wip

* Cleanups

* UI updates

* Update UIFormsController.cs

* Make predefined forms usable statically

* Add support for pos app + forms

* pay request form rough support

* invoice form through receipt page

* Display form name in inherit from store setting

* Do not request additional forms on invoice from pay request

* fix up code

* move checkoutform id in checkout appearance outside of checkotu v2 toggle

* general fixes for form system

* fix pav bug

* UI updates

* Fix warnings in Form builder (#4331)

* Fix build warnings about string?

Enable nullable on UIFormsController.cs
Fixes CS8632 The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.

* Clean up lack of space in injected services in Submit() of UIFormsController.cs

* Remove unused variables (CS0219) and assignment of nullable value to nullable type (CS8600)

* Cleanup double semicolons while we're at tit

* Fix: If reverse proxy wasn't well configured, and error message should have been displayed (#4322)

* fix monero issue

* Server Settings: Update Policies page (#4326)

Handles the multiple submit buttons on that page and closes #4319.

Contains some UI unifications with other pages and also shows the block explorers without needing to toggle the section via JS.

* Change confirmed to settled. (#4328)

* POS: Fix null pointer

Introduced in #4307, the referenced object needs to be `itemChoice` instead of `choice`.

* Add documentation link to plugins (#4329)

* Add documentation link to plugins

* Minor UI updates

Co-authored-by: Dennis Reimann <mail@dennisreimann.de>

* Fix flaky test (#4330)

* Fix flaky test

* Update BTCPayServer/PayoutProcessors/BaseAutomatedPayoutProcessor.cs

Co-authored-by: d11n <mail@dennisreimann.de>

Co-authored-by: d11n <mail@dennisreimann.de>

* Remove invoice and store level form

* add form test

* fix migration for forms

* fix

* make pay request form submission redirect to invoice

* Refactor FormQuery to only be able to query single store and single form

* Put the Authorize at controller level on UIForms

* Fix warnings

* Fix ef request

* Fix query to forms, ensure no permission bypass

* Fix modify

* Remove storeId from step form

* Remove useless storeId parameter

* Hide custom form feature in UI

* Minor cleanups

* Remove custom form options from select for now

* More minor syntax cleanups

* Update test

* Add index - needs migration

* Refactoring: Use PostRedirect instead of TempData for data transfer

* Remove untested and unfinished code

* formResponse should be a JObject, not a string

* Fix case for Form type

Co-authored-by: Dennis Reimann <mail@dennisreimann.de>
Co-authored-by: JesterHodl <103882255+jesterhodl@users.noreply.github.com>
Co-authored-by: Nicolas Dorier <nicolas.dorier@gmail.com>
Co-authored-by: Andreas Tasch <andy.tasch@gmail.com>

BTCPayServer.Abstractions/CamelCaseSerializerSettings.cs

@@ -0,0 +1,18 @@
+using Newtonsoft.Json;
+
+namespace BTCPayServer.Abstractions
+{
+    public class CamelCaseSerializerSettings
+    {
+        static CamelCaseSerializerSettings()
+        {
+            Settings = new JsonSerializerSettings()
+            {
+                ContractResolver = new Newtonsoft.Json.Serialization.CamelCasePropertyNamesContractResolver()
+            };
+            Serializer = JsonSerializer.Create(Settings);
+        }
+        public static readonly JsonSerializerSettings Settings;
+        public static readonly JsonSerializer Serializer;
+    }
+}

BTCPayServer.Abstractions/Form/Field.cs

@@ -1,35 +1,34 @@
+using System;
+using System.Collections;
 using System.Collections.Generic;
+using System.Linq;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
 
 namespace BTCPayServer.Abstractions.Form;
 
-public abstract class Field
+public class Field
 {
-    // HTML5 compatible type string like "text", "textarea", "email", "password", etc. Each type is a class and may contain more fields (i.e. "select" would have options).
-    public string Type;
-    
     // The name of the HTML5 node. Should be used as the key for the posted data.
     public string Name;
 
-    // The translated label of the field.
+    // HTML5 compatible type string like "text", "textarea", "email", "password", etc. Each type is a class and may contain more fields (i.e. "select" would have options).
-    public string Label;
+    public string Type;
 
     // The value field is what is currently in the DB or what the user entered, but possibly not saved yet due to validation errors.
     // If this is the first the user sees the form, then value and original value are the same. Value changes as the user starts interacting with the form.
     public string Value;
 
-    // The original value is the value that is currently saved in the backend. A "reset" button can be used to revert back to this. Should only be set from the constructor.
-    public string OriginalValue;
-
-    // A useful note shown below the field or via a tooltip / info icon. Should be translated for the user.
-    public string HelpText;
-    
     // The field is considered "valid" if there are no validation errors
     public List<string> ValidationErrors = new List<string>();
 
-    public bool Required = false;
+    public virtual bool IsValid()
-
-    public bool IsValid()
     {
-        return ValidationErrors.Count == 0;
+        return ValidationErrors.Count == 0 && Fields.All(field => field.IsValid());
     }
+
+    [JsonExtensionData] public IDictionary<string, JToken> AdditionalData { get; set; }
+    public List<Field> Fields { get; set; } = new();
+    
+   
 }

BTCPayServer.Abstractions/Form/Fieldset.cs

@@ -1,14 +1,12 @@
-using System.Collections.Generic;
-
 namespace BTCPayServer.Abstractions.Form;
 
-public class Fieldset
+public class Fieldset : Field
 {
+    public bool Hidden { get; set; }
+    public string Label { get; set; }
+
     public Fieldset()
     {
-        this.Fields = new List<Field>();
+        Type = "fieldset";
     }
-
-    public string Label { get; set; }
-    public List<Field> Fields { get; set; }
 }

BTCPayServer.Abstractions/Form/Form.cs

@@ -1,60 +1,154 @@
+using System;
 using System.Collections.Generic;
+using System.Linq;
+using Microsoft.AspNetCore.Http;
+using Newtonsoft.Json.Linq;
 
 namespace BTCPayServer.Abstractions.Form;
 
 public class Form
 {
-
+#nullable enable
+    public static Form Parse(string str)
+    {
+        ArgumentNullException.ThrowIfNull(str);
+        return JObject.Parse(str).ToObject<Form>(CamelCaseSerializerSettings.Serializer) ?? throw new InvalidOperationException("Impossible to deserialize Form");
+    }
+    public override string ToString()
+    {
+        return JObject.FromObject(this, CamelCaseSerializerSettings.Serializer).ToString(Newtonsoft.Json.Formatting.Indented);
+    }
+#nullable restore
     // Messages to be shown at the top of the form indicating user feedback like "Saved successfully" or "Please change X because of Y." or a warning, etc...
     public List<AlertMessage> TopMessages { get; set; } = new();
     
     // Groups of fields in the form
-    public List<Fieldset> Fieldsets { get; set; } = new();
+    public List<Field> Fields { get; set; } = new();
-    
     
     // Are all the fields valid in the form?
     public bool IsValid()
     {
-        foreach (var fieldset in Fieldsets)
+        return Fields.All(field => field.IsValid());
-        {
-            foreach (var field in fieldset.Fields)
-            {
-                if (!field.IsValid())
-                {
-                    return false;
-                }
-            }
-        }
-
-        return true;
     }
 
     public Field GetFieldByName(string name)
     {
-        foreach (var fieldset in Fieldsets)
+        return GetFieldByName(name, Fields, null);
+    }
+    
+    private static Field GetFieldByName(string name, List<Field> fields, string prefix)
     {
-            foreach (var field in fieldset.Fields)
+        prefix ??= string.Empty;
+        foreach (var field in fields)
         {
-                if (name.Equals(field.Name))
+            var currentPrefix = prefix;
+            if (!string.IsNullOrEmpty(field.Name))
+            {
+                
+                currentPrefix = $"{prefix}{field.Name}";
+                if (currentPrefix.Equals(name, StringComparison.InvariantCultureIgnoreCase))
                 {
                     return field;
                 }
+
+                currentPrefix += "_";
             }
+
+            var subFieldResult = GetFieldByName(name, field.Fields, currentPrefix);
+            if (subFieldResult is not null)
+            {
+                return subFieldResult;
+            }
+            
         }
         return null;
     }
-
     public List<string> GetAllNames()
     {
-        var names = new List<string>();
+        return GetAllNames(Fields);
-        foreach (var fieldset in Fieldsets)
+    }
+
+    private static List<string> GetAllNames(List<Field> fields)
     {
-            foreach (var field in fieldset.Fields)
+        var names = new List<string>();
+        
+        foreach (var field in fields)
+        {
+            string prefix = string.Empty;
+            if (!string.IsNullOrEmpty(field.Name))
             {
                 names.Add(field.Name);
+                prefix = $"{field.Name}_";
+            }
+
+            if (field.Fields.Any())
+            {
+                names.AddRange(GetAllNames(field.Fields).Select(s => $"{prefix}{s}" ));
             }
         }
 
         return names;
     }
+
+    public void ApplyValuesFromOtherForm(Form form)
+    {
+        foreach (var fieldset in Fields)
+        {
+            foreach (var field in fieldset.Fields)
+            {
+                field.Value = form
+                    .GetFieldByName(
+                        $"{(string.IsNullOrEmpty(fieldset.Name) ? string.Empty : fieldset.Name + "_")}{field.Name}")
+                    ?.Value;
+            }
+        }
+    }
+    
+    public void ApplyValuesFromForm(IFormCollection form)
+    {
+        var names = GetAllNames();
+        foreach (var name in names)
+        {
+            var field = GetFieldByName(name);
+            if (field is null || !form.TryGetValue(name, out var val))
+            {
+                continue;
+            }
+
+            field.Value = val;
+        }
+    }
+
+    public Dictionary<string, object> GetValues()
+    {
+        return GetValues(Fields);
+    }
+    
+    private static Dictionary<string, object> GetValues(List<Field> fields)
+    {
+        var result = new Dictionary<string, object>();
+        foreach (Field field in fields)
+        {
+            var name = field.Name ?? string.Empty;
+            if (field.Fields.Any())
+            {
+                var values = GetValues(fields);
+                values.Remove(string.Empty, out var keylessValue);
+                
+                result.TryAdd(name, values);
+
+                if (keylessValue is not Dictionary<string, object> dict) continue;
+                foreach (KeyValuePair<string,object> keyValuePair in dict)
+                {
+                    result.TryAdd(keyValuePair.Key, keyValuePair.Value);
+                }
+            }
+            else
+            {
+                result.TryAdd(name, field.Value);
+            }
+        }
+
+        return result;
+    }
 }

BTCPayServer.Abstractions/Form/HtmlInputField.cs

@@ -0,0 +1,27 @@
+namespace BTCPayServer.Abstractions.Form;
+
+public class HtmlInputField : Field
+{
+    // The translated label of the field.
+    public string Label;
+    
+    // The original value is the value that is currently saved in the backend. A "reset" button can be used to revert back to this. Should only be set from the constructor.
+    public string OriginalValue;
+
+    // A useful note shown below the field or via a tooltip / info icon. Should be translated for the user.
+    public string HelpText;
+
+    public bool Required;
+    public HtmlInputField(string label, string name, string value, bool required, string helpText, string type = "text")
+    {
+        Label = label;
+        Name = name;
+        Value = value;
+        OriginalValue = value;
+        Required = required;
+        HelpText = helpText;
+        Type = type;
+    }
+
+    // TODO JSON parsing from string to objects again probably won't work out of the box because of the different field types.
+}

BTCPayServer.Abstractions/Form/TextField.cs

@@ -1,19 +0,0 @@
-namespace BTCPayServer.Abstractions.Form;
-
-public class TextField : Field
-{
-    public TextField(string label, string name, string value, bool required, string helpText)
-    {
-        this.Label = label;
-        this.Name = name;
-        this.Value = value;
-        this.OriginalValue = value;
-        this.Required = required;
-        this.HelpText = helpText;
-        this.Type = "text";
-    }
-
-    // TODO JSON parsing from string to objects again probably won't work out of the box because of the different field types. 
-    
-
-}

BTCPayServer.Client/Models/CreateAppRequest.cs

@@ -37,7 +37,7 @@ namespace BTCPayServer.Client.Models
         public string RedirectUrl { get; set; } = null;
         public bool? RedirectAutomatically { get; set; } = null;
         public bool? RequiresRefundEmail { get; set; } = null;
-        public string CheckoutFormId { get; set; } = null;
+        public string FormId { get; set; } = null;
         public string EmbeddedCSS { get; set; } = null;
         public CheckoutType? CheckoutType { get; set; } = null;
     }

BTCPayServer.Client/Models/InvoiceData.cs

@@ -85,8 +85,6 @@ namespace BTCPayServer.Client.Models
             public bool? RedirectAutomatically { get; set; }
             public bool? RequiresRefundEmail { get; set; } = null;
             public string DefaultLanguage { get; set; }
-            [JsonProperty("checkoutFormId")]
-            public string CheckoutFormId { get; set; }
             public CheckoutType? CheckoutType { get; set; }
         }
     }

BTCPayServer.Client/Models/PaymentRequestBaseData.cs

@@ -24,5 +24,9 @@ namespace BTCPayServer.Client.Models
 
         [JsonExtensionData]
         public IDictionary<string, JToken> AdditionalData { get; set; }
+
+        public string FormId { get; set; }
+
+        public JObject FormResponse { get; set; }
     }
 }

BTCPayServer.Client/Models/PaymentRequestData.cs

@@ -12,7 +12,6 @@ namespace BTCPayServer.Client.Models
         public DateTimeOffset CreatedTime { get; set; }
         public string Id { get; set; }
         public bool Archived { get; set; }
-
         public enum PaymentRequestStatus
         {
             Pending = 0,

BTCPayServer.Client/Models/StoreBaseData.cs

@@ -31,8 +31,6 @@ namespace BTCPayServer.Client.Models
         public bool AnyoneCanCreateInvoice { get; set; }
         public string DefaultCurrency { get; set; }
         public bool RequiresRefundEmail { get; set; }
-
-        public string CheckoutFormId { get; set; }
         [JsonConverter(typeof(StringEnumConverter))]
         public CheckoutType CheckoutType { get; set; }
         public bool LightningAmountInSatoshi { get; set; }

BTCPayServer.Data/Data/FormData.cs

@@ -0,0 +1,12 @@
+using System.ComponentModel.DataAnnotations.Schema;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+
+namespace BTCPayServer.Data.Data;
+
+public class FormData
+{
+    public string Id { get; set; }
+    public string Name { get; set; }
+    public string Config { get; set; }
+}

BTCPayServer.Tests/GreenfieldAPITests.cs

@@ -1599,13 +1599,11 @@ namespace BTCPayServer.Tests
                     {
                         RedirectAutomatically = true,
                         RequiresRefundEmail = true,
-                        CheckoutFormId = GenericFormOption.Email.ToString()
                     },
                     AdditionalSearchTerms = new string[] { "Banana" }
                 });
             Assert.True(newInvoice.Checkout.RedirectAutomatically);
             Assert.True(newInvoice.Checkout.RequiresRefundEmail);
-            Assert.Equal(GenericFormOption.Email.ToString(), newInvoice.Checkout.CheckoutFormId);
             Assert.Equal(user.StoreId, newInvoice.StoreId);
             //list 
             var invoices = await viewOnly.GetInvoices(user.StoreId);

BTCPayServer.Tests/SeleniumTests.cs

@@ -64,6 +64,61 @@ namespace BTCPayServer.Tests
             s.Driver.Quit();
         }
         
+        [Fact(Timeout = TestTimeout)]
+        public async Task CanUseForms()
+        {
+            using var s = CreateSeleniumTester();
+            await s.StartAsync();
+            s.RegisterNewUser(true);
+            s.CreateNewStore();
+            s.GenerateWallet(isHotWallet: true);
+            
+            // Point Of Sale
+            s.Driver.FindElement(By.Id("StoreNav-CreateApp")).Click();
+            new SelectElement(s.Driver.FindElement(By.Id("SelectedAppType"))).SelectByValue("PointOfSale");
+            s.Driver.FindElement(By.Id("AppName")).SendKeys(Guid.NewGuid().ToString());
+            s.Driver.FindElement(By.Id("Create")).Click();
+            Assert.Contains("App successfully created", s.FindAlertMessage().Text);
+            
+            new SelectElement(s.Driver.FindElement(By.Id("FormId"))).SelectByValue("Email");
+            s.Driver.FindElement(By.Id("SaveSettings")).Click();
+            Assert.Contains("App updated", s.FindAlertMessage().Text);
+
+            s.Driver.FindElement(By.Id("ViewApp")).Click();
+            var windows = s.Driver.WindowHandles;
+            Assert.Equal(2, windows.Count);
+            s.Driver.SwitchTo().Window(windows[1]);
+            s.Driver.FindElement(By.CssSelector("button[type='submit']")).Click();
+            
+            Assert.Contains("Enter your email", s.Driver.PageSource);
+            s.Driver.FindElement(By.Name("buyerEmail")).SendKeys("aa@aa.com");
+            s.Driver.FindElement(By.CssSelector("input[type='submit']")).Click();
+            
+            s.PayInvoice(true);
+            var invoiceId = s.Driver.Url[(s.Driver.Url.LastIndexOf("/", StringComparison.Ordinal) + 1)..];
+            s.GoToInvoice(invoiceId);
+            Assert.Contains("aa@aa.com", s.Driver.PageSource);
+            
+            // Payment Request
+            s.Driver.FindElement(By.Id("StoreNav-PaymentRequests")).Click();
+            s.Driver.FindElement(By.Id("CreatePaymentRequest")).Click();
+            s.Driver.FindElement(By.Id("Title")).SendKeys("Pay123");
+            s.Driver.FindElement(By.Id("Amount")).SendKeys("700");
+            new SelectElement(s.Driver.FindElement(By.Id("FormId"))).SelectByValue("Email");
+            s.Driver.FindElement(By.Id("SaveButton")).Click();
+            
+            s.Driver.FindElement(By.XPath("//a[starts-with(@id, 'Edit-')]")).Click();
+            var editUrl = s.Driver.Url;
+            s.Driver.FindElement(By.Id("ViewPaymentRequest")).Click();
+            s.Driver.FindElement(By.CssSelector("[data-test='form-button']")).Click();
+            Assert.Contains("Enter your email", s.Driver.PageSource);
+            
+            s.Driver.FindElement(By.Name("buyerEmail")).SendKeys("aa@aa.com");
+            s.Driver.FindElement(By.CssSelector("input[type='submit']")).Click();
+            s.Driver.Navigate().GoToUrl(editUrl);
+            Assert.Contains("aa@aa.com", s.Driver.PageSource);
+        }
+        
         [Fact(Timeout = TestTimeout)]
         public async Task CanUseCPFP()
         {

BTCPayServer/Controllers/GreenField/GreenfieldAppsController.cs

@@ -233,7 +233,7 @@ namespace BTCPayServer.Controllers.Greenfield
                 EmbeddedCSS = request.EmbeddedCSS,
                 RedirectAutomatically = request.RedirectAutomatically,
                 RequiresRefundEmail = BoolToRequiresRefundEmail(request.RequiresRefundEmail) ?? RequiresRefundEmail.InheritFromStore,
-                CheckoutFormId = request.CheckoutFormId,
+                FormId = request.FormId,
                 CheckoutType = request.CheckoutType ?? CheckoutType.V1
             };
         }

BTCPayServer/Controllers/GreenField/GreenfieldInvoiceController.cs

@@ -437,7 +437,6 @@ namespace BTCPayServer.Controllers.Greenfield
                     DefaultLanguage = entity.DefaultLanguage,
                     RedirectAutomatically = entity.RedirectAutomatically,
                     RequiresRefundEmail = entity.RequiresRefundEmail,
-                    CheckoutFormId = entity.CheckoutFormId,
                     CheckoutType = entity.CheckoutType,
                     RedirectURL = entity.RedirectURLTemplate
                 },

BTCPayServer/Controllers/GreenField/GreenfieldStoresController.cs

@@ -127,7 +127,6 @@ namespace BTCPayServer.Controllers.Greenfield
                 //we do not include PaymentMethodCriteria because moving the CurrencyValueJsonConverter to the Client csproj is hard and requires a refactor (#1571 & #1572)
                 NetworkFeeMode = storeBlob.NetworkFeeMode,
                 RequiresRefundEmail = storeBlob.RequiresRefundEmail,
-                CheckoutFormId = storeBlob.CheckoutFormId,
                 CheckoutType = storeBlob.CheckoutType,
                 Receipt = InvoiceDataBase.ReceiptOptions.Merge(storeBlob.ReceiptOptions, null),
                 LightningAmountInSatoshi = storeBlob.LightningAmountInSatoshi,
@@ -167,7 +166,6 @@ namespace BTCPayServer.Controllers.Greenfield
             blob.NetworkFeeMode = restModel.NetworkFeeMode;
             blob.DefaultCurrency = restModel.DefaultCurrency;
             blob.RequiresRefundEmail = restModel.RequiresRefundEmail;
-            blob.CheckoutFormId = restModel.CheckoutFormId;
             blob.CheckoutType = restModel.CheckoutType;
             blob.ReceiptOptions = InvoiceDataBase.ReceiptOptions.Merge(restModel.Receipt, null);
             blob.LightningAmountInSatoshi = restModel.LightningAmountInSatoshi;

BTCPayServer/Controllers/UIInvoiceController.UI.cs

@@ -179,6 +179,11 @@ namespace BTCPayServer.Controllers
             }
             JToken? receiptData = null;
             i.Metadata?.AdditionalData?.TryGetValue("receiptData", out receiptData);
+            string? formResponse = null;
+            if (i.Metadata?.AdditionalData?.TryGetValue("formResponse", out var formResponseRaw)is true)
+            {
+                formResponseRaw.Value<string>();
+            }
                 
             var payments = i.GetPayments(true)
                 .Select(paymentEntity =>
@@ -229,7 +234,6 @@ namespace BTCPayServer.Controllers
                     ? new Dictionary<string, object>()
                     : PosDataParser.ParsePosData(receiptData.ToString())
             });
-
         }
         private string? GetTransactionLink(PaymentMethodId paymentMethodId, string txId)
         {
@@ -760,7 +764,6 @@ namespace BTCPayServer.Controllers
                 CustomLogoLink = storeBlob.CustomLogo,
                 LogoFileId = storeBlob.LogoFileId,
                 BrandColor = storeBlob.BrandColor,
-                CheckoutFormId = invoice.CheckoutFormId ?? storeBlob.CheckoutFormId,
                 CheckoutType = invoice.CheckoutType ?? storeBlob.CheckoutType,
                 HtmlTitle = storeBlob.HtmlTitle ?? "BTCPay Invoice",
                 CryptoImage = Request.GetRelativePathOrAbsolute(paymentMethodHandler.GetCryptoImage(paymentMethodId)),
@@ -1140,9 +1143,6 @@ namespace BTCPayServer.Controllers
                     RequiresRefundEmail = model.RequiresRefundEmail == RequiresRefundEmail.InheritFromStore
                         ? storeBlob.RequiresRefundEmail
                         : model.RequiresRefundEmail == RequiresRefundEmail.On,
-                    CheckoutFormId = model.CheckoutFormId == GenericFormOption.InheritFromStore.ToString()
-                        ? storeBlob.CheckoutFormId
-                        : model.CheckoutFormId
                 }, store, HttpContext.Request.GetAbsoluteRoot(), cancellationToken: cancellationToken);
 
                 TempData[WellKnownTempData.SuccessMessage] = $"Invoice {result.Data.Id} just created!";

BTCPayServer/Controllers/UIInvoiceController.cs

@@ -142,7 +142,6 @@ namespace BTCPayServer.Controllers
             entity.RedirectAutomatically =
                 invoice.RedirectAutomatically.GetValueOrDefault(storeBlob.RedirectAutomatically);
             entity.RequiresRefundEmail = invoice.RequiresRefundEmail;
-            entity.CheckoutFormId = invoice.CheckoutFormId;
             entity.SpeedPolicy = ParseSpeedPolicy(invoice.TransactionSpeed, store.SpeedPolicy);
 
             IPaymentFilter? excludeFilter = null;
@@ -227,7 +226,6 @@ namespace BTCPayServer.Controllers
             entity.DefaultLanguage = invoice.Checkout.DefaultLanguage;
             entity.DefaultPaymentMethod = invoice.Checkout.DefaultPaymentMethod;
             entity.RedirectAutomatically = invoice.Checkout.RedirectAutomatically ?? storeBlob.RedirectAutomatically;
-            entity.CheckoutFormId = invoice.Checkout.CheckoutFormId;
             entity.CheckoutType = invoice.Checkout.CheckoutType;
             entity.RequiresRefundEmail = invoice.Checkout.RequiresRefundEmail;
             IPaymentFilter? excludeFilter = null;

BTCPayServer/Controllers/UIPaymentRequestController.cs

@@ -9,6 +9,7 @@ using BTCPayServer.Client;
 using BTCPayServer.Client.Models;
 using BTCPayServer.Data;
 using BTCPayServer.Filters;
+using BTCPayServer.Models;
 using BTCPayServer.Models.PaymentRequestViewModels;
 using BTCPayServer.PaymentRequest;
 using BTCPayServer.Services.Invoices;
@@ -16,9 +17,11 @@ using BTCPayServer.Services.PaymentRequests;
 using BTCPayServer.Services.Rates;
 using BTCPayServer.Services.Stores;
 using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Http.Extensions;
 using Microsoft.AspNetCore.Identity;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Routing;
+using Newtonsoft.Json.Linq;
 using PaymentRequestData = BTCPayServer.Data.PaymentRequestData;
 using StoreData = BTCPayServer.Data.StoreData;
 
@@ -145,6 +148,7 @@ namespace BTCPayServer.Controllers
             blob.EmbeddedCSS = viewModel.EmbeddedCSS;
             blob.CustomCSSLink = viewModel.CustomCSSLink;
             blob.AllowCustomPaymentAmounts = viewModel.AllowCustomPaymentAmounts;
+            blob.FormId = viewModel.FormId;
 
             data.SetBlob(blob);
             var isNewPaymentRequest = string.IsNullOrEmpty(payReqId);
@@ -174,6 +178,51 @@ namespace BTCPayServer.Controllers
             return View(result);
         }
 
+        [HttpGet("{payReqId}/form")]
+        [HttpPost("{payReqId}/form")]
+        [AllowAnonymous]
+        public async Task<IActionResult> ViewPaymentRequestForm(string payReqId, [FromForm] string formId, [FromForm] string formData)
+        {
+            var result = await _PaymentRequestRepository.FindPaymentRequest(payReqId, GetUserId());
+            if (result == null)
+            {
+                return NotFound();
+            }
+
+            var prBlob = result.GetBlob();
+            var prFormId = prBlob.FormId;
+            switch (prFormId)
+            {
+                case null:
+                case { } when string.IsNullOrEmpty(prFormId):
+                    break;
+                
+                default:
+                    // POST case: Handle form submit
+                    if (!string.IsNullOrEmpty(formData) && formId == prFormId)
+                    {
+                        prBlob.FormResponse = JObject.Parse(formData);
+                        result.SetBlob(prBlob);
+                        await _PaymentRequestRepository.CreateOrUpdatePaymentRequest(result);
+                        return RedirectToAction("PayPaymentRequest", new { payReqId });
+                    }
+                    
+                    // GET or empty form data case: Redirect to form
+                    return View("PostRedirect", new PostRedirectViewModel
+                    {
+                        AspController = "UIForms",
+                        AspAction = "ViewPublicForm",
+                        FormParameters =
+                        {
+                            { "formId", prFormId },
+                            { "redirectUrl", Request.GetCurrentUrl() }
+                        }
+                    });
+            }
+            
+            return RedirectToAction("ViewPaymentRequest", new { payReqId });
+        }
+        
         [HttpGet("{payReqId}/pay")]
         [AllowAnonymous]
         public async Task<IActionResult> PayPaymentRequest(string payReqId, bool redirectToInvoice = true,

BTCPayServer/Data/CustodianAccountDataExtensions.cs

@@ -1,3 +1,4 @@
+using BTCPayServer.Services.Invoices;
 using Newtonsoft.Json.Linq;
 
 namespace BTCPayServer.Data;
@@ -8,7 +9,7 @@ public static class CustodianAccountDataExtensions
     {
         var result = custodianAccountData.Blob == null
             ? new JObject()
-            : JObject.Parse(ZipUtils.Unzip(custodianAccountData.Blob));
+            : InvoiceRepository.FromBytes<JObject>(custodianAccountData.Blob);
         return result;
     }
 
@@ -17,7 +18,8 @@ public static class CustodianAccountDataExtensions
         var original = custodianAccountData.GetBlob();
         if (JToken.DeepEquals(original, blob))
             return false;
-        custodianAccountData.Blob = blob is null ? null : ZipUtils.Zip(blob.ToString(Newtonsoft.Json.Formatting.None));
+        
+        custodianAccountData.Blob = blob is null ? null : InvoiceRepository.ToBytes(blob);
         return true;
     }
 }

BTCPayServer/Data/StoreBlob.cs

@@ -38,7 +38,6 @@ namespace BTCPayServer.Data
 
         [JsonConverter(typeof(Newtonsoft.Json.Converters.StringEnumConverter))]
         public CheckoutType CheckoutType { get; set; }
-        public string CheckoutFormId { get; set; }
         public bool RequiresRefundEmail { get; set; }
         public bool LightningAmountInSatoshi { get; set; }
         public bool LightningPrivateRouteHints { get; set; }

BTCPayServer/Forms/FormComponentProvider.cs

@@ -0,0 +1,20 @@
+using System.Collections.Generic;
+using System.Linq;
+using BTCPayServer.Abstractions.Form;
+
+namespace BTCPayServer.Forms;
+
+public class FormComponentProvider : IFormComponentProvider
+{
+    private readonly IEnumerable<IFormComponentProvider> _formComponentProviders;
+
+    public FormComponentProvider(IEnumerable<IFormComponentProvider> formComponentProviders)
+    {
+        _formComponentProviders = formComponentProviders;
+    }
+    
+    public string CanHandle(Field field)
+    {
+        return _formComponentProviders.Select(formComponentProvider => formComponentProvider.CanHandle(field)).FirstOrDefault(result => !string.IsNullOrEmpty(result));
+    }
+}

BTCPayServer/Forms/FormDataExtensions.cs

@@ -0,0 +1,22 @@
+using BTCPayServer.Data.Data;
+using Microsoft.Extensions.DependencyInjection;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+
+namespace BTCPayServer.Forms;
+
+public static class FormDataExtensions
+{
+    public static void AddForms(this IServiceCollection serviceCollection)
+    {
+        serviceCollection.AddSingleton<FormDataService>();
+        serviceCollection.AddSingleton<FormComponentProvider>();
+        serviceCollection.AddSingleton<IFormComponentProvider, HtmlInputFormProvider>();
+        serviceCollection.AddSingleton<IFormComponentProvider, HtmlFieldsetFormProvider>();
+    }
+
+    public static string Serialize(this JObject form)
+    {
+        return JsonConvert.SerializeObject(form);
+    }
+}

BTCPayServer/Forms/FormDataService.cs

@@ -0,0 +1,35 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using BTCPayServer.Abstractions.Form;
+using BTCPayServer.Data;
+using BTCPayServer.Data.Data;
+using Microsoft.EntityFrameworkCore;
+
+namespace BTCPayServer.Forms;
+
+public class FormDataService
+{
+
+    public static readonly Form StaticFormEmail = new()
+    {
+        Fields = new List<Field>() {new HtmlInputField("Enter your email", "buyerEmail", null, true, null)}
+    };
+
+    public static readonly Form StaticFormAddress = new()
+    {
+        Fields = new List<Field>()
+        {
+            new HtmlInputField("Enter your email", "buyerEmail", null, true, null, "email"),
+            new HtmlInputField("Name", "buyerName", null, true, null),
+            new HtmlInputField("Address Line 1", "buyerAddress1", null, true, null),
+            new HtmlInputField("Address Line 2", "buyerAddress2", null, false, null),
+            new HtmlInputField("City", "buyerCity", null, true, null),
+            new HtmlInputField("Postcode", "buyerZip", null, false, null),
+            new HtmlInputField("State", "buyerState", null, false, null),
+            new HtmlInputField("Country", "buyerCountry", null, true, null)
+        }
+    };
+}

BTCPayServer/Forms/HtmlFieldsetFormProvider.cs

@@ -0,0 +1,12 @@
+using System.Linq;
+using BTCPayServer.Abstractions.Form;
+
+namespace BTCPayServer.Forms;
+
+public class HtmlFieldsetFormProvider: IFormComponentProvider
+{
+    public string CanHandle(Field field)
+    {
+        return new[] { "fieldset"}.Contains(field.Type) ? "Forms/FieldSetElement" : null;
+    }
+}

BTCPayServer/Forms/HtmlInputFormProvider.cs

@@ -0,0 +1,34 @@
+using System.Linq;
+using BTCPayServer.Abstractions.Form;
+
+namespace BTCPayServer.Forms;
+
+public class HtmlInputFormProvider: IFormComponentProvider
+{
+    public string CanHandle(Field field)
+    {
+        return new[] {
+            "text",
+            "radio",
+            "checkbox",
+            "password",
+            "file",
+            "hidden",
+            "button",
+            "submit",
+            "color",
+            "date",
+            "datetime-local",
+            "month",
+            "week",
+            "time",
+            "email",
+            "image",
+            "number",
+            "range",
+            "search",
+            "url",
+            "tel",
+            "reset"}.Contains(field.Type) ? "Forms/InputElement" : null;
+    }
+}

BTCPayServer/Forms/IFormComponentProvider.cs

@@ -0,0 +1,8 @@
+using BTCPayServer.Abstractions.Form;
+
+namespace BTCPayServer.Forms;
+
+public interface IFormComponentProvider
+{
+    public string CanHandle(Field field);
+}

BTCPayServer/Forms/Models/FormViewModel.cs

@@ -0,0 +1,13 @@
+using BTCPayServer.Abstractions.Form;
+using BTCPayServer.Data.Data;
+using Newtonsoft.Json.Linq;
+
+namespace BTCPayServer.Forms.Models;
+
+public class FormViewModel
+{
+    public string RedirectUrl { get; set; }
+    public FormData FormData { get; set; }
+    Form _Form;
+    public Form Form { get => _Form ??= Form.Parse(FormData.Config); }
+}

BTCPayServer/Forms/ModifyForm.cs

@@ -0,0 +1,11 @@
+using System.ComponentModel;
+
+namespace BTCPayServer.Forms;
+
+public class ModifyForm
+{
+    public string Name { get; set; }
+    
+    [DisplayName("Form configuration (JSON)")]
+    public string FormConfig { get; set; }
+}

BTCPayServer/Forms/UIFormsController.cs

@@ -0,0 +1,99 @@
+#nullable enable
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Threading.Tasks;
+using BTCPayServer.Abstractions.Constants;
+using BTCPayServer.Abstractions.Extensions;
+using BTCPayServer.Abstractions.Form;
+using BTCPayServer.Abstractions.Models;
+using BTCPayServer.Client;
+using BTCPayServer.Client.Models;
+using BTCPayServer.Controllers;
+using BTCPayServer.Data;
+using BTCPayServer.Data.Data;
+using BTCPayServer.Forms.Models;
+using BTCPayServer.Models;
+using BTCPayServer.Services.Stores;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+
+namespace BTCPayServer.Forms;
+
+[Authorize(Policy = Policies.CanModifyStoreSettings, AuthenticationSchemes = AuthenticationSchemes.Cookie)]
+public class UIFormsController : Controller
+{
+    [AllowAnonymous]
+    [HttpGet("~/forms/{formId}")]
+    [HttpPost("~/forms")]
+    public IActionResult ViewPublicForm(string? formId, string? redirectUrl)
+    {
+        FormData? formData = string.IsNullOrEmpty(formId) ? null : GetFormData(formId);
+        if (formData == null)
+        {
+            return string.IsNullOrEmpty(redirectUrl)
+                ? NotFound()
+                : Redirect(redirectUrl);
+        }
+        
+        return View("View", new FormViewModel() { FormData = formData, RedirectUrl = redirectUrl });
+    }
+
+    [AllowAnonymous]
+    [HttpPost("~/forms/{formId}")]
+    public IActionResult SubmitForm(
+        string formId, string? redirectUrl,
+        [FromServices] StoreRepository storeRepository,  
+        [FromServices] UIInvoiceController invoiceController)
+    {
+        var formData = GetFormData(formId);
+        if (formData?.Config is null)
+        {
+            return NotFound();
+        }
+
+        var dbForm = Form.Parse(formData.Config);
+        dbForm.ApplyValuesFromForm(Request.Form);
+        Dictionary<string, object> data = dbForm.GetValues();
+        
+        // With redirect, the form comes from another entity that we need to send the data back to
+        if (!string.IsNullOrEmpty(redirectUrl))
+        {
+            return View("PostRedirect", new PostRedirectViewModel
+            {
+                FormUrl = redirectUrl,
+                FormParameters =
+                {
+                    { "formId", formId },
+                    { "formData", JsonConvert.SerializeObject(data) }
+                }
+            });
+        }
+
+        return NotFound();
+    }
+
+    private FormData? GetFormData(string id)
+    {
+        FormData? form = id switch
+        {
+            { } formId when formId == GenericFormOption.Address.ToString() => new FormData
+            {
+                Config = FormDataService.StaticFormAddress.ToString(),
+                Id = GenericFormOption.Address.ToString(),
+                Name = "Provide your address",
+            },
+            { } formId when formId == GenericFormOption.Email.ToString() => new FormData
+            {
+                Config = FormDataService.StaticFormEmail.ToString(),
+                Id = GenericFormOption.Email.ToString(),
+                Name = "Provide your email address",
+            },
+            _ => null
+        };
+        return form;
+    }
+}

BTCPayServer/Hosting/BTCPayServerServices.cs

@@ -15,6 +15,7 @@ using BTCPayServer.Controllers;
 using BTCPayServer.Controllers.Greenfield;
 using BTCPayServer.Data;
 using BTCPayServer.Data.Payouts.LightningLike;
+using BTCPayServer.Forms;
 using BTCPayServer.HostedServices;
 using BTCPayServer.Lightning;
 using BTCPayServer.Logging;
@@ -437,6 +438,7 @@ namespace BTCPayServer.Hosting
             //also provide a factory that can impersonate user/store id
             services.AddSingleton<IBTCPayServerClientFactory, BTCPayServerClientFactory>();
             services.AddPayoutProcesors();
+            services.AddForms();
 
             services.AddAPIKeyAuthentication();
             services.AddBtcPayServerAuthenticationSchemes();

BTCPayServer/Models/BitpayCreateInvoiceRequest.cs

@@ -82,9 +82,6 @@ namespace BTCPayServer.Models
         [JsonProperty(PropertyName = "requiresRefundEmail", DefaultValueHandling = DefaultValueHandling.Ignore)]
         public bool? RequiresRefundEmail { get; set; }
 
-        [JsonProperty(PropertyName = "checkoutFormId", DefaultValueHandling = DefaultValueHandling.Ignore)]
-        public string CheckoutFormId { get; set; }
-
         //Bitpay compatibility: create invoice in btcpay uses this instead of supportedTransactionCurrencies
         [JsonProperty(PropertyName = "paymentCurrencies", DefaultValueHandling = DefaultValueHandling.Ignore)]
         public IEnumerable<string> PaymentCurrencies { get; set; }

BTCPayServer/Models/InvoiceResponse.cs

@@ -268,9 +268,6 @@ namespace BTCPayServer.Models
         public Dictionary<string, InvoiceCryptoInfo.InvoicePaymentUrls> PaymentCodes { get; set; }
         [JsonProperty("buyer")]
         public JObject Buyer { get; set; }
-
-        [JsonProperty("checkoutFormId")]
-        public string CheckoutFormId { get; set; }
         [JsonConverter(typeof(StringEnumConverter))]
         public CheckoutType? CheckoutType { get; set; }
     }

BTCPayServer/Models/InvoicingModels/CreateInvoiceModel.cs

@@ -89,9 +89,6 @@ namespace BTCPayServer.Models.InvoicingModels
             get; set;
         }
 
-        [Display(Name = "Request customer data on checkout")]
-        public string CheckoutFormId { get; set; }
-
         public bool UseNewCheckout { get; set; }
     }
 }

BTCPayServer/Models/InvoicingModels/PaymentModel.cs

@@ -72,7 +72,6 @@ namespace BTCPayServer.Models.InvoicingModels
         public bool Activated { get; set; }
         public string InvoiceCurrency { get; set; }
         public string ReceiptLink { get; set; }
-        public string CheckoutFormId { get; set; }
         public bool AltcoinsBuild { get; set; }
         public CheckoutType CheckoutType { get; set; }
     }

BTCPayServer/Models/PaymentRequestViewModels/ListPaymentRequestsViewModel.cs

@@ -8,6 +8,7 @@ using BTCPayServer.Services.Invoices;
 using BTCPayServer.Services.Rates;
 using BTCPayServer.Validation;
 using Microsoft.AspNetCore.Mvc.Rendering;
+using Newtonsoft.Json.Linq;
 using PaymentRequestData = BTCPayServer.Data.PaymentRequestData;
 
 namespace BTCPayServer.Models.PaymentRequestViewModels
@@ -35,6 +36,7 @@ namespace BTCPayServer.Models.PaymentRequestViewModels
             StoreId = data.StoreDataId;
             Archived = data.Archived;
             var blob = data.GetBlob();
+            FormId = blob.FormId;
             Title = blob.Title;
             Amount = blob.Amount;
             Currency = blob.Currency;
@@ -44,8 +46,14 @@ namespace BTCPayServer.Models.PaymentRequestViewModels
             CustomCSSLink = blob.CustomCSSLink;
             EmbeddedCSS = blob.EmbeddedCSS;
             AllowCustomPaymentAmounts = blob.AllowCustomPaymentAmounts;
+            FormResponse = blob.FormResponse is null
+                ? null
+                : blob.FormResponse.ToObject<Dictionary<string, object>>();
         }
 
+        [Display(Name = "Request customer data on checkout")]
+        public string FormId { get; set; }
+
         public bool Archived { get; set; }
 
         public string Id { get; set; }
@@ -77,6 +85,8 @@ namespace BTCPayServer.Models.PaymentRequestViewModels
         public string EmbeddedCSS { get; set; }
         [Display(Name = "Allow payee to create invoices in their own denomination")]
         public bool AllowCustomPaymentAmounts { get; set; }
+
+        public Dictionary<string, object> FormResponse { get; set; }
     }
 
     public class ViewPaymentRequestViewModel
@@ -165,6 +175,8 @@ namespace BTCPayServer.Models.PaymentRequestViewModels
         public bool PendingInvoiceHasPayments { get; set; }
         public string HubPath { get; set; }
         public bool Archived { get; set; }
+        public string FormId { get; set; }
+        public bool FormSubmitted { get; set; }
 
         public class PaymentRequestInvoice
         {

BTCPayServer/PaymentRequest/PaymentRequestService.cs

@@ -97,6 +97,8 @@ namespace BTCPayServer.PaymentRequest
                 AmountDueFormatted = _currencies.FormatCurrency(amountDue, blob.Currency),
                 CurrencyData = _currencies.GetCurrencyData(blob.Currency, true),
                 LastUpdated = DateTime.UtcNow,
+                FormId = blob.FormId,
+                FormSubmitted = blob.FormResponse is not null,
                 AnyPendingInvoice = pendingInvoice != null,
                 PendingInvoiceHasPayments = pendingInvoice != null &&
                                             pendingInvoice.ExceptionStatus != InvoiceExceptionStatus.None,

BTCPayServer/Plugins/PointOfSale/Controllers/UIPointOfSaleController.cs

@@ -18,6 +18,7 @@ using BTCPayServer.ModelBinders;
 using BTCPayServer.Models;
 using BTCPayServer.Plugins.PointOfSale.Models;
 using BTCPayServer.Services.Apps;
+using BTCPayServer.Services.Invoices;
 using BTCPayServer.Services.Rates;
 using BTCPayServer.Services.Stores;
 using Microsoft.AspNetCore.Authorization;
@@ -25,6 +26,7 @@ using Microsoft.AspNetCore.Cors;
 using Microsoft.AspNetCore.Http.Extensions;
 using Microsoft.AspNetCore.Mvc;
 using NBitpayClient;
+using Newtonsoft.Json.Linq;
 using NicolasDorier.RateLimits;
 
 namespace BTCPayServer.Plugins.PointOfSale.Controllers
@@ -116,6 +118,8 @@ namespace BTCPayServer.Plugins.PointOfSale.Controllers
                                                         string notificationUrl,
                                                         string redirectUrl,
                                                         string choiceKey,
+                                                        string formId = null,
+                                                        string formData = null,
                                                         string posData = null,
                                                         RequiresRefundEmail requiresRefundEmail = RequiresRefundEmail.InheritFromStore,
                                                         CancellationToken cancellationToken = default)
@@ -214,7 +218,42 @@ namespace BTCPayServer.Plugins.PointOfSale.Controllers
                     }
                 }
             }
+
             var store = await _appService.GetStore(app);
+            var posFormId = settings.FormId;
+            JObject formResponse = null;
+            switch (posFormId)
+            {
+                case null:
+                case { } when string.IsNullOrEmpty(posFormId):
+                    break;
+                
+                default:
+                    // POST case: Handle form submit
+                    if (!string.IsNullOrEmpty(formData) && formId == posFormId)
+                    {
+                        formResponse = JObject.Parse(formData);
+                        break;
+                    }
+                    
+                    var query = new QueryBuilder(Request.Query);
+                    foreach (var keyValuePair in Request.Form)
+                    {
+                        query.Add(keyValuePair.Key, keyValuePair.Value.ToArray());
+                    }
+                    
+                    // GET or empty form data case: Redirect to form
+                    return View("PostRedirect", new PostRedirectViewModel
+                    {
+                        AspController = "UIForms",
+                        AspAction = "ViewPublicForm",
+                        FormParameters =
+                        {
+                            { "formId", posFormId },
+                            { "redirectUrl", Request.GetCurrentUrl() + query }
+                        }
+                    });
+            }
             try
             {
                 var invoice = await _invoiceController.CreateInvoiceCore(new BitpayCreateInvoiceRequest
@@ -235,7 +274,6 @@ namespace BTCPayServer.Plugins.PointOfSale.Controllers
                     PosData = string.IsNullOrEmpty(posData) ? null : posData,
                     RedirectAutomatically = settings.RedirectAutomatically,
                     SupportedTransactionCurrencies = paymentMethods,
-                    CheckoutFormId = store.GetStoreBlob().CheckoutFormId,
                     RequiresRefundEmail = requiresRefundEmail == RequiresRefundEmail.InheritFromStore
                         ? store.GetStoreBlob().RequiresRefundEmail
                         : requiresRefundEmail == RequiresRefundEmail.On,
@@ -244,6 +282,13 @@ namespace BTCPayServer.Plugins.PointOfSale.Controllers
                     cancellationToken, (entity) =>
                     {
                         entity.Metadata.OrderUrl = Request.GetDisplayUrl();
+                        
+                        if (formResponse is not null)
+                        {
+                            var meta = entity.Metadata.ToJObject();
+                            meta.Merge(formResponse);
+                            entity.Metadata = InvoiceMetadata.FromJObject(meta);
+                        }
                     } );
                 return RedirectToAction(nameof(UIInvoiceController.Checkout), "UIInvoice", new { invoiceId = invoice.Data.Id });
             }
@@ -298,8 +343,7 @@ namespace BTCPayServer.Plugins.PointOfSale.Controllers
                 SearchTerm = app.TagAllInvoices ? $"storeid:{app.StoreDataId}" : $"orderid:{AppService.GetAppOrderId(app)}",
                 RedirectAutomatically = settings.RedirectAutomatically.HasValue ? settings.RedirectAutomatically.Value ? "true" : "false" : "",
                 RequiresRefundEmail = settings.RequiresRefundEmail,
-                CheckoutFormId = settings.CheckoutFormId,
+                FormId = settings.FormId
-                UseNewCheckout = storeBlob.CheckoutType == Client.Models.CheckoutType.V2
             };
             if (HttpContext?.Request != null)
             {
@@ -390,13 +434,7 @@ namespace BTCPayServer.Plugins.PointOfSale.Controllers
                 RequiresRefundEmail = vm.RequiresRefundEmail
             };
 
-            if (storeBlob.CheckoutType == Client.Models.CheckoutType.V2)
+            settings.FormId = vm.FormId;
-            {
-                settings.CheckoutFormId = vm.CheckoutFormId == GenericFormOption.InheritFromStore.ToString()
-                    ? storeBlob.CheckoutFormId
-                    : vm.CheckoutFormId;
-            }
-
             app.Name = vm.AppName;
             app.SetSettings(settings);
             await _appService.UpdateOrCreateApp(app);

BTCPayServer/Plugins/PointOfSale/Models/UpdatePointOfSaleViewModel.cs

@@ -103,8 +103,6 @@ namespace BTCPayServer.Plugins.PointOfSale.Models
         public RequiresRefundEmail RequiresRefundEmail { get; set; } = RequiresRefundEmail.InheritFromStore;
 
         [Display(Name = "Request customer data on checkout")]
-        public string CheckoutFormId { get; set; } = GenericFormOption.InheritFromStore.ToString();
+        public string FormId { get; set; } = null;
-
-        public bool UseNewCheckout { get; set; }
     }
 }

BTCPayServer/Services/Apps/PointOfSaleSettings.cs

@@ -58,7 +58,7 @@ namespace BTCPayServer.Services.Apps
             public bool EnableTips { get; set; }
             public RequiresRefundEmail RequiresRefundEmail { get; set; }
 
-            public string CheckoutFormId { get; set; } = GenericFormOption.InheritFromStore.ToString();
+            public string FormId { get; set; } = null;
 
             public const string BUTTON_TEXT_DEF = "Buy for {0}";
             public string ButtonText { get; set; } = BUTTON_TEXT_DEF;

BTCPayServer/Services/Invoices/InvoiceEntity.cs

@@ -446,8 +446,6 @@ namespace BTCPayServer.Services.Invoices
         [JsonProperty(DefaultValueHandling = DefaultValueHandling.Ignore)]
         public InvoiceDataBase.ReceiptOptions ReceiptOptions { get; set; }
 
-        [JsonProperty("checkoutFormId")]
-        public string CheckoutFormId { get; set; }
         [JsonConverter(typeof(StringEnumConverter))]
         public CheckoutType? CheckoutType { get; set; }
 
@@ -578,7 +576,6 @@ namespace BTCPayServer.Services.Invoices
             dto.TaxIncluded = Metadata.TaxIncluded ?? 0m;
             dto.Price = Price;
             dto.Currency = Currency;
-            dto.CheckoutFormId = CheckoutFormId;
             dto.CheckoutType = CheckoutType;
             dto.Buyer = new JObject();
             dto.Buyer.Add(new JProperty("name", Metadata.BuyerName));

BTCPayServer/Services/PaymentRequests/PaymentRequestRepository.cs

@@ -22,7 +22,7 @@ namespace BTCPayServer.Services.PaymentRequests
 
         public async Task<PaymentRequestData> CreateOrUpdatePaymentRequest(PaymentRequestData entity)
         {
-            using var context = _ContextFactory.CreateContext();
+            await using var context = _ContextFactory.CreateContext();
             if (string.IsNullOrEmpty(entity.Id))
             {
                 entity.Id = Guid.NewGuid().ToString();

BTCPayServer/Services/Stores/CheckoutFormSelectList.cs

@@ -1,17 +1,12 @@
-using System;
 using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using System.Linq;
-using BTCPayServer.Data;
 using Microsoft.AspNetCore.Mvc.Rendering;
 
 namespace BTCPayServer.Services.Stores;
 
 public enum GenericFormOption
 {
-   [Display(Name = "Inherit from store settings")]
-   InheritFromStore,
-
    [Display(Name = "Do not request any information")]
    None,
 
@@ -24,24 +19,14 @@ public enum GenericFormOption
 
 public static class CheckoutFormSelectList
 {
-    public static SelectList ForStore(StoreData store, string selectedFormId, bool isStoreEntity)
+    public static SelectList WithSelected(string selectedFormId)
     {
-        var choices = new List<SelectListItem>();
+        var choices = new List<SelectListItem>
-
-        if (isStoreEntity)
         {
-            var blob = store.GetStoreBlob();
+            GenericOptionItem(GenericFormOption.None),
-            var inherit = GenericOptionItem(GenericFormOption.InheritFromStore);
+            GenericOptionItem(GenericFormOption.Email),
-            inherit.Text += Enum.TryParse<GenericFormOption>(blob.CheckoutFormId, out var item)
+            GenericOptionItem(GenericFormOption.Address)
-                ? $" ({DisplayName(item)})"
+        };
-                : $" ({blob.CheckoutFormId})";
-            
-            choices.Add(inherit);
-        }
-        
-        choices.Add(GenericOptionItem(GenericFormOption.None));
-        choices.Add(GenericOptionItem(GenericFormOption.Email));
-        choices.Add(GenericOptionItem(GenericFormOption.Address));
         
         var chosen = choices.FirstOrDefault(t => t.Value == selectedFormId);
         return new SelectList(choices, nameof(SelectListItem.Value), nameof(SelectListItem.Text), chosen?.Value);

BTCPayServer/Views/Shared/Forms/FieldSetElement.cshtml

@@ -0,0 +1,27 @@
+@using BTCPayServer.Abstractions.Form
+@using BTCPayServer.Forms
+@using Microsoft.AspNetCore.Mvc.TagHelpers
+@using Newtonsoft.Json.Linq
+@inject FormComponentProvider FormComponentProvider
+@model BTCPayServer.Abstractions.Form.Field
+@{
+    if (Model is not Fieldset fieldset)
+    {
+        fieldset = JObject.FromObject(Model).ToObject<Fieldset>();
+    }
+}
+@if (!fieldset.Hidden)
+{
+    <fieldset>
+        <legend class="h3 mt-4 mb-3">@fieldset.Label</legend>
+        @foreach (var field in fieldset.Fields)
+        {
+            var partial = FormComponentProvider.CanHandle(field);
+            if (string.IsNullOrEmpty(partial))
+            {
+                continue;
+            }
+            <partial name="@partial" for="@field"></partial>
+        }
+    </fieldset>
+}

BTCPayServer/Views/Shared/Forms/InputElement.cshtml

@@ -0,0 +1,33 @@
+@using BTCPayServer.Abstractions.Form
+@using Newtonsoft.Json.Linq
+@model BTCPayServer.Abstractions.Form.Field
+@{
+    if (Model is not HtmlInputField field)
+    {
+        field = JObject.FromObject(Model).ToObject<HtmlInputField>();
+    }
+}
+<div class="form-group">
+    @if (field.Required)
+    {
+        <label class="form-label" for="@field.Name" data-required>
+            @field.Label
+        </label>
+    }
+    else
+    {
+        <label class="form-label" for="@field.Name">
+            @field.Label
+        </label>
+    }
+
+    <input class="form-control @(field.IsValid() ? "" : "is-invalid")" id="@field.Name" type="@field.Type" required="@field.Required" name="@field.Name" value="@field.Value" aria-describedby="@("HelpText" + field.Name)"/>
+    @if (!string.IsNullOrEmpty(field.HelpText))
+    {
+        <small id="@("HelpText" + field.Name)" class="form-text text-muted">
+            @field.HelpText
+        </small>
+    }
+
+
+</div>

BTCPayServer/Views/Shared/PointOfSale/UpdatePointOfSale.cshtml

@@ -7,8 +7,7 @@
 @{
     ViewData.SetActivePage(AppsNavPages.Update, "Update Point of Sale", Model.Id);
     
-    var store = ViewContext.HttpContext.GetStoreData();
+    var checkoutFormOptions = CheckoutFormSelectList.WithSelected(Model.FormId);
-    var checkoutFormOptions = CheckoutFormSelectList.ForStore(store, Model.CheckoutFormId, true);
 }
 
 <form method="post">
@@ -84,18 +83,14 @@
                 <span asp-validation-for="ButtonText" class="text-danger"></span>
             </div>
             <div class="form-group">
-                @if (Model.UseNewCheckout)
+                <label asp-for="FormId" class="form-label"></label>
-                {
+                <select asp-for="FormId" class="form-select w-auto" asp-items="@checkoutFormOptions"></select>
-                    <label asp-for="CheckoutFormId" class="form-label"></label>
+                <span asp-validation-for="FormId" class="text-danger"></span>
-                    <select asp-for="CheckoutFormId" class="form-select w-auto" asp-items="@checkoutFormOptions"></select>
+            </div>
-                    <span asp-validation-for="CheckoutFormId" class="text-danger"></span>
+            <div class="form-group">
-                }
-                else
-                {
                 <label asp-for="RequiresRefundEmail" class="form-label"></label>
                 <select asp-for="RequiresRefundEmail" asp-items="@Html.GetEnumSelectList<RequiresRefundEmail>()" class="form-select w-auto"></select>
                 <span asp-validation-for="RequiresRefundEmail" class="text-danger"></span>
-                }
             </div>
             <section id="discounts" class="p-0">
                 <h3 class="mt-5 mb-4">Discounts</h3>

BTCPayServer/Views/Shared/PosData.cshtml

@@ -0,0 +1,60 @@
+@model (Dictionary<string, object> Items, int Level)
+
+@functions {
+    private bool IsValidURL(string source)
+    {
+        return Uri.TryCreate(source, UriKind.Absolute, out var uriResult) && 
+            (uriResult.Scheme == Uri.UriSchemeHttp || uriResult.Scheme == Uri.UriSchemeHttps);
+    }
+}
+
+<table class="table my-0">
+    @foreach (var (key, value) in Model.Items)
+    {
+        <tr>
+            @if (value is string str)
+            {
+                if (!string.IsNullOrEmpty(key))
+                {
+                    <th class="w-150px">@Safe.Raw(key)</th>
+                }
+                <td>
+                    @if (IsValidURL(str))
+                    {
+                        <a href="@Safe.Raw(str)" target="_blank" rel="noreferrer noopener">@Safe.Raw(str)</a>
+                    }
+                    else
+                    {
+                        @Safe.Raw(value?.ToString())
+                    }
+                </td>
+            }
+            else if (value is Dictionary<string, object>subItems)
+            {
+                @* This is the array case *@
+                if (subItems.Count == 1 && subItems.First().Value is string str2)
+                {
+                    <th class="w-150px">@Safe.Raw(key)</th>
+                    <td>
+                        @if (IsValidURL(str2))
+                        {
+                            <a href="@Safe.Raw(str2)" target="_blank" rel="noreferrer noopener">@Safe.Raw(str2)</a>
+                        }
+                        else
+                        {
+                            @Safe.Raw(subItems.First().Value?.ToString())
+                        }
+                    </td>
+                }
+                else
+                {
+                    <td colspan="2" >
+                        @Safe.Raw($"<h{Model.Level + 3} class=\"mt-4 mb-3\">{key}</h{Model.Level + 3}>")
+                        <partial name="PosData" model="(subItems, Model.Level + 1)"/>
+                    </td>
+                }
+            }
+        </tr>
+    }
+</table>
+

BTCPayServer/Views/Shared/_Form.cshtml

@@ -1,34 +1,14 @@
+@using Microsoft.AspNetCore.Mvc.TagHelpers
+@using BTCPayServer.Forms
 @model BTCPayServer.Abstractions.Form.Form
+@inject FormComponentProvider FormComponentProvider
 
-@foreach (var fieldset in Model.Fieldsets)
+@foreach (var field in Model.Fields)
 {
-    <fieldset>
+    var partial = FormComponentProvider.CanHandle(field);
-        <legend class="h3 mt-4 mb-3">@fieldset.Label</legend>
+    if (string.IsNullOrEmpty(partial))
-        @foreach (var field in fieldset.Fields)
     {
-@if ("text".Equals(field.Type))
+        continue;
-{
-    <div class="form-group">
-        @if (field.Required)
-        {
-            <label class="form-label" for="@field.Name" data-required>
-                @field.Label
-            </label>
     }
-        else
+    <partial name="@partial" for="@field"></partial>
-        {
-            <label class="form-label" for="@field.Name">
-                @field.Label
-            </label>
-        }
-
-        <input class="form-control @(field.IsValid() ? "" : "is-invalid")" id="@field.Name" type="text" required="@field.Required" name="@field.Name" value="@field.Value" aria-describedby="HelpText@field.Name"/>
-        <small id="HelpText@field.Name" class="form-text text-muted">
-            @field.HelpText
-        </small>
-
-    </div>
-}
-        }
-    </fieldset>
 }

BTCPayServer/Views/UIForms/View.cshtml

@@ -0,0 +1,56 @@
+@using BTCPayServer.Components.ThemeSwitch
+@using Microsoft.AspNetCore.Mvc.TagHelpers
+@inject BTCPayServer.Services.BTCPayServerEnvironment env
+@inject BTCPayServer.Services.ThemeSettings Theme
+@model BTCPayServer.Forms.Models.FormViewModel
+@{
+    Layout = null;
+    ViewData["Title"] = Model.FormData.Name;
+}
+
+<!DOCTYPE html>
+<html lang="en" @(env.IsDeveloping ? " data-devenv" : "")>
+<head>
+    <partial name="LayoutHead"/>
+    <meta name="robots" content="noindex,nofollow">
+</head>
+<body>
+<div class="min-vh-100 d-flex flex-column">
+    <main class="flex-grow-1 py-5">
+        <div class="container" style="max-width:720px;">
+            <partial name="_StatusMessage" model="@(new ViewDataDictionary(ViewData) {{"Margin", "mb-4"}})"/>
+            @if (!ViewContext.ModelState.IsValid)
+            {
+                <div asp-validation-summary="ModelOnly" class="text-danger"></div>
+            }
+            <partial name="_FormTopMessages" model="@Model.Form"/>
+            <div class="d-flex flex-column justify-content-center gap-4">
+                <h1 class="h3 text-center">@ViewData["Title"]</h1>
+                <div  class="bg-tile p-3 p-sm-4 rounded">
+                    <form asp-action="SubmitForm" asp-route-formId="@Model.FormData.Id">
+                        @if (!string.IsNullOrEmpty(Model.RedirectUrl))
+                        {
+                            <input type="hidden" asp-for="RedirectUrl" value="@Model.RedirectUrl"/>
+                        }
+                        <partial name="_Form" model="@Model.Form"/>
+                        <input type="submit" class="btn btn-primary" value="Submit"/>
+                    </form>
+                </div>
+            </div>
+        </div>
+    </main>
+    <footer class="pt-2 pb-4 d-print-none">
+        <div class="container d-flex flex-wrap align-items-center justify-content-center">
+            <span class="text-muted mx-2">
+                Powered by <a href="https://btcpayserver.org" target="_blank" rel="noreferrer noopener">BTCPay Server</a>
+            </span>
+            @if (!Theme.CustomTheme)
+            {
+                <vc:theme-switch css-class="text-muted mx-2" responsive="none"/>
+            }
+        </div>
+    </footer>
+</div>
+<partial name="LayoutFoot"/>
+</body>
+</html>

BTCPayServer/Views/UIForms/_ViewImports.cshtml

@@ -0,0 +1,3 @@
+@using BTCPayServer.Abstractions.Extensions
+@using BTCPayServer.Views.Stores
+@using BTCPayServer.Models.StoreViewModels

BTCPayServer/Views/UIForms/_ViewStart.cshtml

@@ -0,0 +1,7 @@
+@using BTCPayServer.Abstractions.Extensions
+@using BTCPayServer.Views
+@using BTCPayServer.Views.Stores
+
+@{
+    ViewData.SetActiveCategory(typeof(StoreNavPages));
+}

BTCPayServer/Views/UIInvoice/CreateInvoice.cshtml

@@ -1,11 +1,10 @@
 @model BTCPayServer.Models.InvoicingModels.CreateInvoiceModel
 @using BTCPayServer.Services.Apps
-@using BTCPayServer.Services.Stores
+@using BTCPayServer.TagHelpers
+@using Microsoft.AspNetCore.Mvc.TagHelpers
+@using BTCPayServer.Abstractions.TagHelpers
 @{
     ViewData.SetActivePage(InvoiceNavPages.Create, "Create Invoice");
-    
-    var store = ViewContext.HttpContext.GetStoreData();
-    var checkoutFormOptions = CheckoutFormSelectList.ForStore(store, Model.CheckoutFormId, true);
 }
 
 @section PageFootContent {
@@ -90,22 +89,13 @@
             <h4 class="mt-5 mb-4">Customer Information</h4>
             <div class="form-group">
                 <label asp-for="BuyerEmail" class="form-label"></label>
-                <input asp-for="BuyerEmail" class="form-control" />
+                <input asp-for="BuyerEmail" class="form-control"/>
                 <span asp-validation-for="BuyerEmail" class="text-danger"></span>
             </div>
             <div class="form-group">
-                @if (Model.UseNewCheckout)
-                {
-                    <label asp-for="CheckoutFormId" class="form-label"></label>
-                    <select asp-for="CheckoutFormId" class="form-select w-auto" asp-items="@checkoutFormOptions"></select>
-                    <span asp-validation-for="CheckoutFormId" class="text-danger"></span>
-                }
-                else
-                {
                 <label asp-for="RequiresRefundEmail" class="form-label"></label>
                 <select asp-for="RequiresRefundEmail" asp-items="@Html.GetEnumSelectList<RequiresRefundEmail>()" class="form-select w-auto"></select>
                 <span asp-validation-for="RequiresRefundEmail" class="text-danger"></span>
-                }
             </div>
 
             <h4 class="mt-5 mb-2">Additional Options</h4>

BTCPayServer/Views/UIInvoice/PosData.cshtml

@@ -1,10 +1,9 @@
 @model (Dictionary<string, object> Items, int Level)
 
-@functions{
+@functions {
-    public bool IsValidURL(string source)
+    private bool IsValidURL(string source)
     {
-        Uri uriResult;
+        return Uri.TryCreate(source, UriKind.Absolute, out var uriResult) && 
-        return Uri.TryCreate(source, UriKind.Absolute, out uriResult) && 
             (uriResult.Scheme == Uri.UriSchemeHttp || uriResult.Scheme == Uri.UriSchemeHttps);
     }
 }

BTCPayServer/Views/UIPaymentRequest/EditPaymentRequest.cshtml

@@ -1,7 +1,12 @@
 @using BTCPayServer.Services.PaymentRequests
 @using System.Globalization
+@using BTCPayServer.Services.Stores
+@using BTCPayServer.TagHelpers
+@using Microsoft.AspNetCore.Mvc.TagHelpers
 @model BTCPayServer.Models.PaymentRequestViewModels.UpdatePaymentRequestViewModel
 @{
+    var checkoutFormOptions = CheckoutFormSelectList.WithSelected(Model.FormId);
+
     ViewData.SetActivePage(PaymentRequestsNavPages.Create, $"{(string.IsNullOrEmpty(Model.Id) ? "Create" : "Edit")} Payment Request", Model.Id);
 }
 
@@ -78,6 +83,18 @@
                     Receive updates for this payment request.
                 </p>
             </div>
+            <div class="form-group">
+                <label asp-for="FormId" class="form-label"></label>
+                <select asp-for="FormId" class="form-select w-auto" asp-items="@checkoutFormOptions"></select>
+                <span asp-validation-for="FormId" class="text-danger"></span>
+            </div>
+            
+            @if (Model.FormResponse is not null)
+            {
+                <div class="bg-tile rounded py-2 px-3 mb-5">
+                    <partial name="PosData" model="(Model.FormResponse, 1)"/>
+                </div>
+            }
         </div>
     </div>
 
@@ -146,4 +163,3 @@
         }
     </div>
 }
-

BTCPayServer/Views/UIPaymentRequest/ViewPaymentRequest.cshtml

@@ -144,7 +144,12 @@
                                 </div>
                             }
                         </noscript>
-                        <template v-if="srvModel.isPending && !srvModel.archived" class="d-print-none">
+                        <template v-if="srvModel.formId && srvModel.formId != 'None' && !srvModel.formSubmitted">
+                            <a asp-action="ViewPaymentRequestForm" asp-route-payReqId="@Model.Id" class="btn btn-primary w-100 d-flex d-print-none align-items-center justify-content-center text-nowrap btn-lg" data-test="form-button">
+                                Pay Invoice
+                            </a>
+                        </template>
+                        <template v-else-if="srvModel.isPending && !srvModel.archived">
                             <template v-if="srvModel.allowCustomPaymentAmounts && !srvModel.anyPendingInvoice">
                                 <form v-on:submit="submitCustomAmountForm" class="d-print-none">
                                     <div class="row">

BTCPayServer/Views/UIStores/StoreNavPages.cs

@@ -22,6 +22,7 @@ namespace BTCPayServer.Views.Stores
         PayoutProcessors,
         [Obsolete("Use StoreNavPages.Plugins instead")]
         Integrations,
-        Emails
+        Emails,
+        Forms
     }
 }

BTCPayServer/wwwroot/swagger/v1/swagger.template.apps.json

@@ -434,9 +434,9 @@
                     "checkoutType": {
                         "$ref": "#/components/schemas/CheckoutType"
                     },
-                    "checkoutFormId": {
+                    "formId": {
                         "type": "string",
-                        "description": "Form ID to request customer data, in case the new checkout is used",
+                        "description": "Form ID to request customer data",
                         "nullable": true
                     }
                 }

BTCPayServer/wwwroot/swagger/v1/swagger.template.invoices.json

@@ -1088,11 +1088,6 @@
                             "V2"
                         ]
                     },
-                    "checkoutFormId": {
-                        "type": "string",
-                        "description": "Form ID to request customer data, in case the new checkout is used",
-                        "nullable": true
-                    },
                     "defaultLanguage": {
                         "type": "string",
                         "nullable": true,

BTCPayServer/wwwroot/swagger/v1/swagger.template.payment-requests.json

@@ -470,6 +470,16 @@
                         "type": "boolean",
                         "description": "Whether to allow users to create invoices that partially pay the payment request ",
                         "nullable": true
+                    },
+                    "formId": {
+                        "type": "string",
+                        "description": "Form ID to request customer data",
+                        "nullable": true
+                    },
+                    "formResponse": {
+                        "type": "object",
+                        "description": "Form data response",
+                        "nullable": true
                     }
                 }
             }

BTCPayServer/wwwroot/swagger/v1/swagger.template.stores.json

@@ -344,11 +344,6 @@
                     "checkoutType": {
                         "$ref": "#/components/schemas/CheckoutType"
                     },
-                    "checkoutFormId": {
-                        "type": "string",
-                        "description": "Form ID to request customer data, in case the new checkout is used",
-                        "nullable": true
-                    },
                     "receipt": {
                         "nullable": true,
                         "$ref": "#/components/schemas/ReceiptOptions",

Plugins/BTCPayServer.Plugins.Custodians.FakeCustodian/FakeCustodian.cs

@@ -37,13 +37,13 @@ public class FakeCustodian : ICustodian
         var fieldset = new Fieldset();
 
         // Maybe a decimal type field would be better?
-        var fakeBTCBalance = new TextField("BTC Balance", "BTCBalance", fakeConfig?.BTCBalance.ToString(), true,
+        var fakeBTCBalance = new HtmlInputField("BTC Balance", "BTCBalance", fakeConfig?.BTCBalance.ToString(), true,
             "Enter the amount of BTC you want to have.");
-        var fakeLTCBalance = new TextField("LTC Balance", "LTCBalance", fakeConfig?.LTCBalance.ToString(), true,
+        var fakeLTCBalance = new HtmlInputField("LTC Balance", "LTCBalance", fakeConfig?.LTCBalance.ToString(), true,
             "Enter the amount of LTC you want to have.");
-        var fakeEURBalance = new TextField("EUR Balance", "EURBalance", fakeConfig?.EURBalance.ToString(), true,
+        var fakeEURBalance = new HtmlInputField("EUR Balance", "EURBalance", fakeConfig?.EURBalance.ToString(), true,
             "Enter the amount of EUR you want to have.");
-        var fakeUSDBalance = new TextField("USD Balance", "USDBalance", fakeConfig?.USDBalance.ToString(), true,
+        var fakeUSDBalance = new HtmlInputField("USD Balance", "USDBalance", fakeConfig?.USDBalance.ToString(), true,
             "Enter the amount of USD you want to have.");
 
         fieldset.Label = "Your fake balances";
@@ -51,7 +51,7 @@ public class FakeCustodian : ICustodian
         fieldset.Fields.Add(fakeLTCBalance);
         fieldset.Fields.Add(fakeEURBalance);
         fieldset.Fields.Add(fakeUSDBalance);
-        form.Fieldsets.Add(fieldset);
+        form.Fields.Add(fieldset);
 
         return Task.FromResult(form);
     }