BookLib: Use async methods for database access; improve error handling

jbe2277 · Nov 30, 2024 · ec393ca · ec393ca
1 parent 11f51ac
commit ec393ca
Show file tree

Hide file tree

Showing 13 changed files with 143 additions and 61 deletions.
diff --git a/...les/BookLibrary/BookLibrary.Library.Applications.Test/Controllers/EntityControllerTest.cs b/...les/BookLibrary/BookLibrary.Library.Applications.Test/Controllers/EntityControllerTest.cs
@@ -1,18 +1,18 @@
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System.Waf.Applications;
 using System.Waf.UnitTesting;
 using System.Waf.UnitTesting.Mocks;
 using Waf.BookLibrary.Library.Applications.Controllers;
 using Waf.BookLibrary.Library.Applications.Services;
 using Waf.BookLibrary.Library.Applications.ViewModels;
-using Waf.BookLibrary.Library.Domain;
 
 namespace Test.BookLibrary.Library.Applications.Controllers;
 
 [TestClass]
 public class EntityControllerTest : ApplicationsTest
 {
     [TestMethod]
-    public void ValidateBeforeSave()
+    public async Task ValidateBeforeSave()
     {
         var controller = Get<EntityController>();
         controller.Initialize();
@@ -23,7 +23,7 @@ public void ValidateBeforeSave()
         Assert.IsTrue(controller.HasChanges());
 
         Assert.IsTrue(controller.CanSave());
-        controller.Save();
+        Assert.IsTrue(await controller.SaveCore());
         Assert.IsFalse(controller.HasChanges());
 
         var messageService = Get<MockMessageService>();
@@ -33,7 +33,7 @@ public void ValidateBeforeSave()
         entityService.Persons[^1].Validate();
         Assert.IsTrue(controller.HasChanges());
         var shellViewModel = Get<ShellViewModel>();
-        shellViewModel.SaveCommand!.Execute(null);
+        await ((AsyncDelegateCommand)shellViewModel.SaveCommand!).ExecuteAsync(null);
 
         Assert.AreEqual(MessageType.Error, messageService.MessageType);
         Assert.IsTrue(controller.HasChanges());

diff --git a/...les/BookLibrary/BookLibrary.Library.Applications.Test/Controllers/MockEntityController.cs b/...les/BookLibrary/BookLibrary.Library.Applications.Test/Controllers/MockEntityController.cs
@@ -12,25 +12,19 @@ public class MockEntityController : IEntityController
 
     public bool HasChangesResult { get; set; }
 
-    public bool CanSaveResult { get; set; }
+    public bool CanSaveResult { get; set; } = true;
 
-    public bool SaveResult { get; set; }
+    public Func<Task<bool>>? SaveCoreStub { get; set; }
 
-    public bool SaveCalled { get; set; }
-
-    public MockEntityController() => CanSaveResult = true;
+    public bool SaveCoreCalled { get; set; }
 
     public void Initialize() => InitializeCalled = true;
 
     public bool HasChanges() => HasChangesResult;
 
     public bool CanSave() => CanSaveResult;
 
-    public bool Save()
-    {
-        SaveCalled = true;
-        return SaveResult;
-    }
+    public Task<bool> SaveCore() => SaveCoreStub?.Invoke() ?? Task.FromResult(true);
 
     public void Shutdown() => ShutdownCalled = true;
 }
diff --git a/...les/BookLibrary/BookLibrary.Library.Applications.Test/Controllers/ModuleControllerTest.cs b/...les/BookLibrary/BookLibrary.Library.Applications.Test/Controllers/ModuleControllerTest.cs
@@ -67,33 +67,35 @@ public void ModuleControllerHasChangesTest()
             return true;
         };
         // Then we simulate that the EntityController wasn't able to save the changes.
-        entityController.SaveResult = false;
+        var saveCalled = false;
+        entityController.SaveCoreStub = () =>
+        {
+            saveCalled = true;
+            return Task.FromResult(false);
+        };
         shellViewModel.ExitCommand!.Execute(null);
-        // The Save method must be called. Because the save operation failed the expect the ShellView to be
-        // still visible.
-        Assert.IsTrue(entityController.SaveCalled);
+        // The Save method must be called. Because the save operation failed the expect the ShellView to be still visible.
+        Assert.IsTrue(saveCalled);
         Assert.IsTrue(shellView.IsVisible);
 
         // Exit the application although we have unsaved changes.
         entityController.HasChangesResult = true;
-        entityController.SaveCalled = false;
+        saveCalled = false;
         // When the question box asks us to save the changes we say "Cancel" => null.
         messageService.ShowQuestionStub = (_, _) => null;
-        // This time the Save method must not be called. Because we have chosen "Cancel" the ShellView must still
-        // be visible.
+        // This time the Save method must not be called. Because we have chosen "Cancel" the ShellView must still be visible.
         shellViewModel.ExitCommand.Execute(null);
-        Assert.IsFalse(entityController.SaveCalled);
+        Assert.IsFalse(saveCalled);
         Assert.IsTrue(shellView.IsVisible);
 
         // Exit the application although we have unsaved changes.
         entityController.HasChangesResult = true;
-        entityController.SaveCalled = false;
+        saveCalled = false;
         // When the question box asks us to save the changes we say "No" => false.
         messageService.ShowQuestionStub = (_, _) => false;
-        // This time the Save method must not be called. Because we have chosen "No" the ShellView must still
-        // be closed.
+        // This time the Save method must not be called. Because we have chosen "No" the ShellView must still be closed.
         shellViewModel.ExitCommand.Execute(null);
-        Assert.IsFalse(entityController.SaveCalled);
+        Assert.IsFalse(saveCalled);
         Assert.IsFalse(shellView.IsVisible);
     }
 

diff --git a/...em.Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/BookController.cs b/...em.Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/BookController.cs
@@ -1,6 +1,8 @@
 using System.ComponentModel.Composition;
 using System.Waf.Applications;
+using System.Waf.Applications.Services;
 using Waf.BookLibrary.Library.Applications.DataModels;
+using Waf.BookLibrary.Library.Applications.Properties;
 using Waf.BookLibrary.Library.Applications.Services;
 using Waf.BookLibrary.Library.Applications.ViewModels;
 using Waf.BookLibrary.Library.Domain;
@@ -11,6 +13,7 @@ namespace Waf.BookLibrary.Library.Applications.Controllers;
 [Export]
 internal class BookController
 {
+    private readonly IMessageService messageService;
     private readonly IShellService shellService;
     private readonly IEntityService entityService;
     private readonly BookListViewModel bookListViewModel;
@@ -22,8 +25,10 @@ internal class BookController
     private SynchronizingList<BookDataModel, Book>? bookDataModels;
 
     [ImportingConstructor]
-    public BookController(IShellService shellService, IEntityService entityService, BookListViewModel bookListViewModel, BookViewModel bookViewModel, ExportFactory<LendToViewModel> lendToViewModelFactory)
+    public BookController(IMessageService messageService, IShellService shellService, IEntityService entityService, BookListViewModel bookListViewModel, 
+        BookViewModel bookViewModel, ExportFactory<LendToViewModel> lendToViewModelFactory)
     {
+        this.messageService = messageService;
         this.shellService = shellService;
         this.entityService = entityService;
         this.bookListViewModel = bookListViewModel;
@@ -36,7 +41,7 @@ public BookController(IShellService shellService, IEntityService entityService,
 
     internal ObservableListViewCore<BookDataModel>? BooksView { get; private set; }
 
-    public void Initialize()
+    public async void Initialize()
     {
         bookViewModel.LendToCommand = lendToCommand;
         bookViewModel.PropertyChanged += BookViewModelPropertyChanged;
@@ -51,6 +56,15 @@ public void Initialize()
         shellService.BookListView = bookListViewModel.View;
         shellService.BookView = bookViewModel.View;
 
+        try
+        {
+            await entityService.LoadBooks();
+        }
+        catch (Exception ex)
+        {
+            Log.Default.Error(ex, "LoadBooks");
+            messageService.ShowError(shellService.ShellView, Resources.LoadErrorBooks);
+        }
         bookListViewModel.SelectedBook = bookListViewModel.Books.FirstOrDefault();
     }
 

diff --git a/....Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/EntityController.cs b/....Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/EntityController.cs
@@ -18,7 +18,7 @@ internal class EntityController : IEntityController
     private readonly IShellService shellService;
     private readonly IDBContextService dBContextService;
     private readonly Lazy<ShellViewModel> shellViewModel;
-    private readonly DelegateCommand saveCommand;
+    private readonly AsyncDelegateCommand saveCommand;
     private DbContext? bookLibraryContext;
 
     [ImportingConstructor]
@@ -29,7 +29,7 @@ public EntityController(EntityService entityService, IMessageService messageServ
         this.shellService = shellService;
         this.dBContextService = dBContextService;
         this.shellViewModel = shellViewModel;
-        saveCommand = new(() => Save(), CanSave);
+        saveCommand = new(Save, CanSave);
     }
 
     private ShellViewModel ShellViewModel => shellViewModel.Value;
@@ -50,7 +50,22 @@ public void Initialize()
 
     public bool CanSave() => ShellViewModel.IsValid;
 
-    public bool Save()
+    public async Task<bool> SaveCore()
+    {
+        Log.Default.Info("Save changes in database.");
+        try
+        {
+            await entityService.SaveChanges().ConfigureAwait(false);
+            return true;
+        }
+        catch (Exception ex)
+        {
+            Log.Default.Error(ex, "SaveChangesAsync");            
+        }
+        return false;
+    }
+
+    private async Task Save()
     {
         var entities = bookLibraryContext!.ChangeTracker.Entries().Where(x => x.State == EntityState.Added || x.State == EntityState.Modified).Select(x => x.Entity).ToArray();
         var errors = entities.OfType<ValidatableModel>().Where(x => x.HasErrors).ToArray();
@@ -59,12 +74,13 @@ public bool Save()
             var errorMessages = errors.Select(x => string.Format(CultureInfo.CurrentCulture, Resources.EntityInvalid, EntityToString(x), string.Join(Environment.NewLine, x.Errors)));
             Log.Default.Warn("Abort save changes because of errors: {0}", string.Join("; ", errorMessages));
             messageService.ShowError(shellService.ShellView, Resources.SaveErrorInvalidEntities, string.Join(Environment.NewLine, errorMessages));
-            return false;
+            return;
         }
 
-        Log.Default.Info("Save changes in database.");
-        bookLibraryContext.SaveChanges();
-        return true;
+        if (!await SaveCore())
+        {
+            messageService.ShowError(shellService.ShellView, Resources.SaveErrorDatabase);
+        }
     }
 
     private void ShellViewModelPropertyChanged(object? sender, PropertyChangedEventArgs e)

diff --git a/...Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/IEntityController.cs b/...Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/IEntityController.cs
@@ -9,7 +9,7 @@ internal interface IEntityController
 
     bool CanSave();
 
-    bool Save();
+    Task<bool> SaveCore();
 
     void Shutdown();
 }
diff --git a/....Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/ModuleController.cs b/....Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/ModuleController.cs
@@ -56,8 +56,9 @@ private void ShellViewModelClosing(object? sender, CancelEventArgs e)
             bool? result = messageService.ShowQuestion(shellService.ShellView, Resources.SaveChangesQuestion);
             if (result == true)
             {
-                if (!entityController.Save())
+                if (!entityController.SaveCore().GetAwaiter().GetResult())
                 {
+                    messageService.ShowError(shellService.ShellView, Resources.SaveErrorDatabase);
                     e.Cancel = true;
                 }
             }

diff --git a/....Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/PersonController.cs b/....Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Controllers/PersonController.cs
@@ -39,18 +39,30 @@ public PersonController(IMessageService messageService, IShellService shellServi
 
     internal ObservableListViewCore<Person>? PersonsView { get; private set; }
 
-    public void Initialize()
+    public async void Initialize()
     {
         personViewModel.CreateNewEmailCommand = createNewEmailCommand;
         personViewModel.PropertyChanged += PersonViewModelPropertyChanged;
+
         PersonsView = new(entityService.Persons, null, personListViewModel.Filter, null);
         personListViewModel.Persons = PersonsView;
         personListViewModel.AddNewCommand = addNewCommand;
         personListViewModel.RemoveCommand = removeCommand;
         personListViewModel.CreateNewEmailCommand = createNewEmailCommand;
         personListViewModel.PropertyChanged += PersonListViewModelPropertyChanged;
+
         shellService.PersonListView = personListViewModel.View;
         shellService.PersonView = personViewModel.View;
+
+        try
+        {
+            await entityService.LoadPersons();
+        }
+        catch (Exception ex)
+        {
+            Log.Default.Error(ex, "LoadPersons");
+            messageService.ShowError(shellService.ShellView, Resources.LoadErrorPersons);
+        }
         personListViewModel.SelectedPerson = personListViewModel.Persons.FirstOrDefault();
     }
 

diff --git a/src/System.Waf/Samples/BookLibrary/BookLibrary.Library.Applications/GlobalSuppressions.cs b/src/System.Waf/Samples/BookLibrary/BookLibrary.Library.Applications/GlobalSuppressions.cs
@@ -2,7 +2,6 @@
 [assembly: SuppressMessage("Microsoft.Design", "CA1001:TypesThatOwnDisposableFieldsShouldBeDisposable", Scope = "type", Target = "~T:Waf.BookLibrary.Library.Applications.Controllers.EntityController")]
 [assembly: SuppressMessage("Microsoft.Naming", "CA1702:CompoundWordsShouldBeCasedCorrectly", MessageId = "BookList", Scope = "type", Target = "~T:Waf.BookLibrary.Library.Applications.ViewModels.BookListViewModel")]
 [assembly: SuppressMessage("Microsoft.Naming", "CA1702:CompoundWordsShouldBeCasedCorrectly", MessageId = "BookList", Scope = "type", Target = "~T:Waf.BookLibrary.Library.Applications.Views.IBookListView")]
-[assembly: SuppressMessage("Microsoft.Naming", "CA2204:Literals should be spelled correctly", MessageId = "CanSave", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.Controllers.EntityController.Save~System.Boolean")]
 [assembly: SuppressMessage("Microsoft.Design", "CA1062:Validate arguments of public methods", MessageId = "0", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.ViewModels.PersonListViewModel.Filter(Waf.BookLibrary.Library.Domain.Person)~System.Boolean")]
 [assembly: SuppressMessage("Microsoft.Design", "CA1062:Validate arguments of public methods", MessageId = "0", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.ViewModels.BookListViewModel.Filter(Waf.BookLibrary.Library.Applications.DataModels.BookDataModel)~System.Boolean")]
 [assembly: SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.Controllers.ModuleController.Shutdown")]
@@ -16,4 +15,4 @@
 [assembly: SuppressMessage("Performance", "CA1826:Do not use Enumerable methods on indexable collections", Justification = "<Pending>", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.Controllers.PersonController.Initialize")]
 [assembly: SuppressMessage("Performance", "CA1826:Do not use Enumerable methods on indexable collections", Justification = "<Pending>", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.Controllers.PersonController.RemovePerson")]
 [assembly: SuppressMessage("Design", "CA1062:Validate arguments of public methods", Justification = "<Pending>", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.ViewModels.ShellViewModel.#ctor(Waf.BookLibrary.Library.Applications.Views.IShellView,System.Waf.Applications.Services.IMessageService,Waf.BookLibrary.Library.Applications.Services.IShellService,System.Waf.Applications.Services.ISettingsService)")]
-[assembly: SuppressMessage("Globalization", "CA1305:Specify IFormatProvider", Justification = "<Pending>", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.Controllers.EntityController.Save~System.Boolean")]
+[assembly: SuppressMessage("Globalization", "CA1305:Specify IFormatProvider", Justification = "<Pending>", Scope = "member", Target = "~M:Waf.BookLibrary.Library.Applications.Controllers.EntityController.Save~System.Threading.Tasks.Task")]
diff --git a/...Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Properties/Resources.Designer.cs b/...Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Properties/Resources.Designer.cs
diff --git a/...System.Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Properties/Resources.resx b/...System.Waf/Samples/BookLibrary/BookLibrary.Library.Applications/Properties/Resources.resx
@@ -148,4 +148,13 @@ https://github.com/jbe2277/waf
 
 {0}</value>
   </data>
+  <data name="SaveErrorDatabase" xml:space="preserve">
+    <value>The save operation failed.</value>
+  </data>
+  <data name="LoadErrorBooks" xml:space="preserve">
+    <value>Could not load the Books from the database.</value>
+  </data>
+  <data name="LoadErrorPersons" xml:space="preserve">
+    <value>Could not load the Persons from the database.</value>
+  </data>
 </root>