Cleanup, update readme, update demos

Author: LucDeCaf

PowerSync/PowerSync.Common/Client/PowerSyncDatabase.cs

@@ -1009,12 +1009,6 @@ public class SQLWatchOptions
     public bool TriggerImmediately { get; set; } = false;
 }
 
-public class WatchHandler<T>
-{
-    public Action<T[]> OnResult { get; set; } = null!;
-    public Action<Exception>? OnError { get; set; }
-}
-
 public class WatchOnChangeEvent
 {
     public string[] ChangedTables { get; set; } = [];

PowerSync/PowerSync.Common/README.md

@@ -1,4 +1,4 @@
-# PowerSync SDK .NET Common 
+# PowerSync SDK .NET Common
 
 This package contains a .NET implementation of a PowerSync database connector and streaming sync bucket implementation.
 
@@ -16,7 +16,7 @@ This package is published on [NuGet](https://www.nuget.org/packages/PowerSync.Co
 dotnet add package PowerSync.Common --prerelease
 ```
 
-## Usage 
+## Usage
 
 ### Simple Query
 
@@ -39,24 +39,23 @@ static async Task Main() {
 ```
 
 ### Watched queries
-Watched queries will automatically update when a dependant table is updated. 
-Awaiting `Watch()` ensures the watcher is fully initialized and ready to monitor database changes.
+
+Watched queries will automatically update when a dependant table is updated.
+Call `Watch()` synchronously to ensure the watcher is fully initialized before execution continues.
 
 ```csharp
-await db.Watch("select * from lists", null, new WatchHandler<ListResult>
+var cts = new CancellationTokenSource();
+var listener = db.Watch<ListResult>("select * from lists", null, new SQLWatchOptions { Signal = cts.Token });
+_ = Task.Run(async () =>
 {
-    OnResult = (results) =>
+    await foreach (var results in listener)
     {
         table.Rows.Clear();
         foreach (var line in results)
         {
             table.AddRow(line.id, line.name, line.owner_id, line.created_at);
         }
-    },
-    OnError = (error) =>
-    {
-        Console.WriteLine("Error: " + error.Message);
     }
-});
+}, cts.Token);
+```
 
-```

demos/CommandLine/Demo.cs

@@ -67,23 +67,20 @@ static async Task Main()
 
         bool running = true;
 
-        await db.Watch("select * from lists", null, new WatchHandler<ListResult>
+        var listener = db.Watch<ListResult>("select * from lists");
+        _ = Task.Run(async () =>
         {
-            OnResult = (results) =>
+            await foreach (var results in listener)
             {
                 table.Rows.Clear();
                 foreach (var line in results)
                 {
                     table.AddRow(line.id, line.name, line.owner_id, line.created_at);
                 }
-            },
-            OnError = (error) =>
-            {
-                Console.WriteLine("Error: " + error.Message);
             }
         });
 
-        var _ = Task.Run(async () =>
+        _ = Task.Run(async () =>
          {
              while (running)
              {

demos/MAUITodo/Views/ListsPage.xaml.cs

@@ -34,15 +34,12 @@ protected override async void OnAppearing()
             }
         });
 
-        await database.Db.Watch("select * from lists", null, new WatchHandler<TodoList>
+        var listener = database.Db.Watch<TodoList>("select * from lists", null, new() { TriggerImmediately = true });
+        _ = Task.Run(async () =>
         {
-            OnResult = (results) =>
+            await foreach (var results in listener)
             {
                 MainThread.BeginInvokeOnMainThread(() => { ListsCollection.ItemsSource = results.ToList(); });
-            },
-            OnError = (error) =>
-            {
-                Console.WriteLine("Error: " + error.Message);
             }
         });
     }

demos/MAUITodo/Views/TodoListPage.xaml.cs

@@ -24,15 +24,12 @@ protected override async void OnAppearing()
     {
         base.OnAppearing();
 
-        await database.Db.Watch("select * from todos where list_id = ?", [selectedList.ID], new WatchHandler<TodoItem>
+        var listener = database.Db.Watch<TodoItem>("select * from todos where list_id = ?", [selectedList.ID], new() { TriggerImmediately = true });
+        _ = Task.Run(async () =>
         {
-            OnResult = (results) =>
+            await foreach (var results in listener)
             {
                 MainThread.BeginInvokeOnMainThread(() => { TodoItemsCollection.ItemsSource = results.ToList(); });
-            },
-            OnError = (error) =>
-            {
-                Console.WriteLine("Error: " + error.Message);
             }
         });
     }

demos/WPF/ViewModels/TodoListViewModel.cs

@@ -147,32 +147,25 @@ ORDER BY
                     last_completed_at DESC NULLS LAST;
                 ";
 
-            await _db.Watch(
-                query,
-                null,
-                new WatchHandler<TodoListWithStats>
+            var listener = _db.Watch<TodoListWithStats>(query);
+            _ = Task.Run(async () =>
+            {
+                await foreach (var results in listener)
                 {
-                    OnResult = (results) =>
+                    var dispatcher = System.Windows.Application.Current?.Dispatcher;
+                    if (dispatcher != null)
                     {
-                        var dispatcher = System.Windows.Application.Current?.Dispatcher;
-                        if (dispatcher != null)
+                        dispatcher.Invoke(() =>
                         {
-                            dispatcher.Invoke(() =>
+                            TodoLists.Clear();
+                            foreach (var result in results)
                             {
-                                TodoLists.Clear();
-                                foreach (var result in results)
-                                {
-                                    TodoLists.Add(result);
-                                }
-                            });
-                        }
-                    },
-                    OnError = (error) =>
-                    {
-                        Console.WriteLine("Error: " + error.Message);
-                    },
+                                TodoLists.Add(result);
+                            }
+                        });
+                    }
                 }
-            );
+            });
         }
 
         private async Task AddList(string newListName)

demos/WPF/ViewModels/TodoViewModel.cs

@@ -105,32 +105,25 @@ public void SetList(TodoList list)
 
         private async void WatchForChanges()
         {
-            await _db.Watch(
-                "SELECT * FROM todos where list_id = ? ORDER BY created_at;",
-                [_list!.Id],
-                new WatchHandler<Todo>
+            var listener = _db.Watch<Todo>("SELECT * FROM todos where list_id = ? ORDER BY created_at;", [_list!.Id]);
+            _ = Task.Run(async () =>
+            {
+                await foreach (var results in listener)
                 {
-                    OnResult = (results) =>
+                    var dispatcher = System.Windows.Application.Current?.Dispatcher;
+                    if (dispatcher != null)
                     {
-                        var dispatcher = System.Windows.Application.Current?.Dispatcher;
-                        if (dispatcher != null)
+                        dispatcher.Invoke(() =>
                         {
-                            dispatcher.Invoke(() =>
+                            Todos.Clear();
+                            foreach (var result in results)
                             {
-                                Todos.Clear();
-                                foreach (var result in results)
-                                {
-                                    Todos.Add(result);
-                                }
-                            });
-                        }
-                    },
-                    OnError = (error) =>
-                    {
-                        Console.WriteLine("Error: " + error.Message);
-                    },
+                                Todos.Add(result);
+                            }
+                        });
+                    }
                 }
-            );
+            });
         }
 
         private async void LoadTodos()