Auto Attach the DashboardPart to content types with DashboardWidget stereotype

src/OrchardCore.Modules/OrchardCore.AdminDashboard/AdminDashboardConstants.cs

@@ -0,0 +1,6 @@
+namespace OrchardCore.AdminDashboard;
+
+public static class AdminDashboardConstants
+{
+    public const string Stereotype = "DashboardWidget";
+}

src/OrchardCore.Modules/OrchardCore.AdminDashboard/Controllers/DashboardController.cs

@@ -202,6 +202,6 @@ public async Task<IActionResult> Update([FromForm] DashboardPartViewModel[] part
 
     private async Task<Dictionary<string, ContentTypeDefinition>> GetDashboardWidgetsAsync()
         => (await _contentDefinitionManager.ListTypeDefinitionsAsync())
-        .Where(t => t.StereotypeEquals("DashboardWidget"))
+        .Where(t => t.StereotypeEquals(AdminDashboardConstants.Stereotype))
         .ToDictionary(ctd => ctd.Name, ctd => ctd);
 }

src/OrchardCore.Modules/OrchardCore.AdminDashboard/Migrations.cs

@@ -33,15 +33,10 @@ await SchemaBuilder.AlterIndexTableAsync<DashboardPartIndex>(table => table
                 "Position")
         );
 
-        await _contentDefinitionManager.AlterPartDefinitionAsync("DashboardPart", builder => builder
-            .Attachable()
-            .WithDescription("Provides a way to add widgets to a dashboard.")
-            );
-
         await _recipeMigrator.ExecuteAsync($"dashboard-widgets{RecipesConstants.RecipeExtension}", this);
 
         // Shortcut other migration steps on new content definition schemas.
-        return 3;
+        return 4;
     }
 
     public async Task<int> UpdateFrom1Async()
@@ -62,4 +57,11 @@ await SchemaBuilder.AlterIndexTableAsync<DashboardPartIndex>(table => table
 
         return 3;
     }
+
+    public async Task<int> UpdateFrom3Async()
+    {
+        await _contentDefinitionManager.DeletePartDefinitionAsync("DashboardPart");
+
+        return 4;
+    }
 }

src/OrchardCore.Modules/OrchardCore.AdminDashboard/Services/DashboardPartContentTypeDefinitionHandler.cs

@@ -0,0 +1,100 @@
+using System.Text.Json.Nodes;
+using OrchardCore.AdminDashboard.Models;
+using OrchardCore.ContentManagement.Metadata.Records;
+using OrchardCore.ContentManagement.Metadata.Settings;
+using OrchardCore.ContentTypes.Events;
+using OrchardCore.Modules;
+
+namespace OrchardCore.AdminDashboard.Services;
+
+public sealed class DashboardPartContentTypeDefinitionHandler : IContentDefinitionHandler
+{
+    /// <summary>
+    /// Adds the <see cref="DashboardPart"/> to the content type definition when the stereotype is set to 'DashboardWidget'.
+    /// This occurs during the content type building process, allowing the content type to function as a dashboard widget.
+    /// </summary>
+    public void ContentTypeBuilding(BuildingContentTypeContext context)
+    {
+        if (!context.Record.Settings.TryGetPropertyValue(nameof(ContentTypeSettings), out var node))
+        {
+            return;
+        }
+
+        var settings = node.ToObject<ContentTypeSettings>();
+
+        if (settings.Stereotype == null || !string.Equals(settings.Stereotype, AdminDashboardConstants.Stereotype, StringComparison.OrdinalIgnoreCase))
+        {
+            return;
+        }
+
+        if (context.Record.ContentTypePartDefinitionRecords.Any(x => x.Name.EqualsOrdinalIgnoreCase(nameof(DashboardPart))))
+        {
+            return;
+        }
+
+        context.Record.ContentTypePartDefinitionRecords.Add(new ContentTypePartDefinitionRecord
+        {
+            Name = nameof(DashboardPart),
+            PartName = nameof(DashboardPart),
+            Settings = new JsonObject()
+            {
+                [nameof(ContentSettings)] = JObject.FromObject(new ContentSettings
+                {
+                    IsSystemType = true,
+                }),
+            },
+        });
+    }
+
+    /// <summary>
+    /// Marks the part on the content type as a system type to prevent its removal.
+    /// This ensures that the part remains integral to the content type and cannot be deleted.
+    /// </summary>
+    public void ContentTypePartBuilding(ContentTypePartContextBuilding context)
+    {
+        if (!context.Record.PartName.EqualsOrdinalIgnoreCase(nameof(DashboardPart)))
+        {
+            return;
+        }
+
+        var settings = context.Record.Settings[nameof(ContentSettings)]?.ToObject<ContentSettings>()
+            ?? new ContentSettings();
+
+        settings.IsSystemType = true;
+
+        context.Record.Settings[nameof(ContentSettings)] = JObject.FromObject(settings);
+    }
+
+    /// <summary>
+    /// Creates a definition if the Record is null and the part name is 'DashboardPart'.
+    /// This ensures that the 'DashboardPart' has a valid definition when it is missing.
+    /// </summary>
+    public void ContentPartDefinitionBuilding(ContentPartDefinitionContextBuilding context)
+    {
+        if (context.Record is not null || context.Name != nameof(DashboardPart))
+        {
+            return;
+        }
+
+        context.Record = new ContentPartDefinitionRecord()
+        {
+            Name = context.Name,
+            Settings = new JsonObject()
+            {
+                [nameof(ContentPartSettings)] = JObject.FromObject(new ContentPartSettings
+                {
+                    Attachable = false,
+                    Reusable = true,
+                }),
+                [nameof(ContentSettings)] = JObject.FromObject(new ContentSettings
+                {
+                    IsSystemType = true,
+                }),
+            },
+        };
+    }
+
+    public void ContentPartFieldBuilding(ContentPartFieldContextBuilding context)
+    {
+    }
+}

src/OrchardCore.Modules/OrchardCore.AdminDashboard/Startup.cs

@@ -10,6 +10,7 @@
 using OrchardCore.AdminDashboard.Services;
 using OrchardCore.ContentManagement;
 using OrchardCore.ContentManagement.Display.ContentDisplay;
+using OrchardCore.ContentTypes.Events;
 using OrchardCore.Data;
 using OrchardCore.Data.Migration;
 using OrchardCore.Modules;
@@ -42,6 +43,7 @@ public override void ConfigureServices(IServiceCollection services)
         services.AddScoped<IContentDisplayDriver, DashboardContentDisplayDriver>();
 
         services.AddDataMigration<Migrations>();
+        services.AddScoped<IContentDefinitionHandler, DashboardPartContentTypeDefinitionHandler>();
     }
 
     public override void Configure(IApplicationBuilder builder, IEndpointRouteBuilder routes, IServiceProvider serviceProvider)

src/OrchardCore.Modules/OrchardCore.ContentTypes/Controllers/AdminController.cs

@@ -414,7 +414,14 @@ public async Task<ActionResult> RemovePart(string id, string name)
 
         var typeViewModel = await _contentDefinitionService.LoadTypeAsync(id);
 
-        if (typeViewModel == null || !typeViewModel.TypeDefinition.Parts.Any(p => string.Equals(p.Name, name, StringComparison.OrdinalIgnoreCase)))
+        if (typeViewModel == null)
+        {
+            return NotFound();
+        }
+
+        var partDefinition = typeViewModel.TypeDefinition.Parts.FirstOrDefault(p => string.Equals(p.Name, name, StringComparison.OrdinalIgnoreCase));
+
+        if (partDefinition == null)
         {
             return NotFound();
         }
@@ -440,8 +447,8 @@ public async Task<ActionResult> ListParts()
 
         return View(new ListContentPartsViewModel
         {
-            // only user-defined parts (not code as they are not configurable)
-            Parts = await _contentDefinitionService.GetPartsAsync(true/*metadataPartsOnly*/)
+            // Only user-defined parts (not code as they are not configurable).
+            Parts = await _contentDefinitionService.GetPartsAsync(metadataPartsOnly: true)
         });
     }