src/PostIt.Tests/BlogApiTestFakes.cs

@@ -1,65 +0,0 @@
-using PostIt.Models;
-using PostIt.Services;
-using PostIt.ViewModels;
-
-namespace PostIt.Tests;
-
-/// <summary>Per-call ledger shared between the test and the
-/// recording fake, so the assertion can inspect what the VM
-/// actually sent on the wire without coupling to the fake's
-/// internals.</summary>
-internal sealed class CallRecorder
-{
-    public (HttpMethod method, string path, object? body) FirstCall =>
-        Calls[0];
-    public List<(HttpMethod method, string path, object? body)> Calls { get; } = new();
-}
-
-/// <summary>Test fake that records every CallAsync invocation
-/// and answers them with a canned sequence: the first call gets
-/// a server-issued BlogPost (Id=42), the second call gets a
-/// single-element list containing that post. Used by the ViewModel
-/// tests and the headless UI test to capture exactly what the
-/// Save button posts to the server.</summary>
-internal sealed class RecordingYavscApiClient : YavscApiClient
-{
-    private readonly CallRecorder _recorder;
-    public RecordingYavscApiClient(CallRecorder recorder)
-        : base(
-            new Settings
-            {
-                Authentication = new AuthenticationSettings
-                {
-                    Authority = "https://stub.invalid",
-                    ClientId = "stub",
-                    Scopes = new[] { "openid" },
-                },
-            },
-            new TokenStore(System.IO.Path.GetTempFileName()))
-    {
-        _recorder = recorder;
-    }
-
-    public override Task<T> CallAsync<T>(HttpMethod method, string path, object? body = null, CancellationToken ct = default)
-    {
-        _recorder.Calls.Add((method, path, body));
-        // BlogPost? boxes to BlogPost at runtime, so we test the
-        // non-nullable type — typeof(BlogPost?) is a C# error
-        // (CS8639: "typeof cannot be used on a nullable reference
-        // type").
-        if (typeof(T) == typeof(BlogPost))
-            return Task.FromResult((T)(object)new BlogPost
-            {
-                Id = 42,
-                Title = "Mon premier billet",
-                AuthorId = "tester",
-                Article = "Contenu du billet de test.",
-            });
-        if (typeof(T) == typeof(List<BlogPost>))
-            return Task.FromResult((T)(object)new List<BlogPost>
-            {
-                new() { Id = 42, Title = "Mon premier billet" }
-            });
-        return Task.FromResult(default(T)!);
-    }
-}

src/PostIt.Tests/MainPageSaveTests.cs

@@ -1,89 +0,0 @@
-using Avalonia;
-using Avalonia.Controls;
-using Avalonia.Headless.XUnit;
-using Avalonia.VisualTree;
-using PostIt.Models;
-using PostIt.Services;
-using PostIt.ViewModels;
-using PostIt.Views;
-namespace PostIt.Tests;
-
-/// <summary>
-/// Headless UI tests for the "Save" flow in <see cref="MainPage"/>.
-/// The pattern is the one <c>SessionStatusBannerTests</c>
-/// established: <c>[AvaloniaFact]</c>, a <see cref="Window"/>
-/// hosting the page (via a <see cref="Frame"/> because
-/// <c>MainPage</c> is a <c>ContentPage</c>), then drive the
-/// controls through their public surface and assert on what
-/// <see cref="RecordingYavscApiClient"/> saw go on the wire.
-///
-/// <para>The bug we are pinning: the title <c>TextBox</c> is
-/// currently <c>{Binding SelectedPost.Title, Mode=TwoWay}</c>.
-/// When <c>SelectedPost is null</c> (i.e. the user has not yet
-/// clicked an item in the posts list — which is the only state
-/// in which a brand-new post can be created), the binding has
-/// no target and the user's keystrokes are silently dropped.
-/// Clicking "Save" then routes to the VM branch
-/// <c>if (SelectedPost is null) { new BlogPost { Title = string.Empty, ... } }</c>
-/// which the controller rejects with 400 "The Title field is
-/// required." This test fails on that branch today and will
-/// pass once the VM owns a dedicated <c>Title</c>/<c>Article</c>
-/// buffer that the XAML binds to and the Save command consumes.</para>
-/// </summary>
-public class MainPageSaveTests
-{
-    [AvaloniaFact]
-    public async Task Typing_a_title_then_clicking_Save_sends_that_title_in_the_post_body()
-    {
-        // Arrange: VM with a recording API client, mounted in a
-        // headless window via a Frame (MainPage is a ContentPage,
-        // not a Control, so it needs a navigation host).
-        var recorder = new CallRecorder();
-        var api = new RecordingYavscApiClient(recorder);
-        var blog = new BlogApiClient(api);
-        var viewModel = new MainPageViewModel(blog);
-
-        var page = new MainPage { DataContext = viewModel };
-        // MainPage is a ContentPage (a Page, not a Control), so it
-        // must be hosted in a navigation surface. The production
-        // MainWindow.axaml uses NavigationPage, and the API is the
-        // same one App.axaml.cs drives at boot (PushAsync, fire-
-        // and-forget in prod because the page is the top of the
-        // stack immediately).
-        var nav = new NavigationPage();
-        _ = nav.PushAsync(page);
-        var window = new Window { Content = nav };
-        window.Show();
-
-        // Act: type a title into the editor's TextBox without
-        // first selecting a post in the list — the only state in
-        // which a new post can be created. Then click Save.
-        var titleBox = window.GetVisualDescendants()
-            .OfType<TextBox>()
-            .First(t => t.PlaceholderText == "Title");
-        const string typed = "Mon premier billet";
-        titleBox.Text = typed;
-
-        var saveButton = window.GetVisualDescendants()
-            .OfType<Button>()
-            .Single(b => b.Content as string == "Save");
-        saveButton.Command!.Execute(null);
-
-        // The Save command is async (RelayCommand over Task) but
-        // ExecuteAsync would await; the sync Execute enqueues the
-        // task on the dispatcher. Give the dispatcher a chance to
-        // run so the awaited CallAsync has actually fired before
-        // we inspect the recorder.
-        await Task.Delay(200);
-
-        // Assert: the first POST to "blog" carried a BlogPost
-        // whose Title is exactly what the user typed. The bug
-        // fails this assertion with Title == string.Empty.
-        Assert.NotEmpty(recorder.Calls);
-        var (method, path, body) = recorder.FirstCall;
-        Assert.Equal(HttpMethod.Post, method);
-        Assert.Equal("blog", path);
-        var sent = Assert.IsType<BlogPost>(body);
-        Assert.Equal(typed, sent.Title);
-    }
-}

src/PostIt/PostIt/Services/YavscApiClient.cs

@@ -191,7 +191,7 @@ public class YavscApiClient : IAsyncDisposable
         CancellationToken ct = default)
     {
         using var response = await SendAsync(method, path, body, ct).ConfigureAwait(false);
-        await EnsureSuccessOrThrowAsync(response, ct).ConfigureAwait(false);
+        response.EnsureSuccessStatusCode();
 
         var stream = await response.Content.ReadAsStreamAsync(ct).ConfigureAwait(false);
         var dto = await JsonSerializer.DeserializeAsync<T>(stream,
@@ -217,7 +217,7 @@ public class YavscApiClient : IAsyncDisposable
         CancellationToken ct = default)
     {
         using var response = await SendAsync(method, path, body, ct).ConfigureAwait(false);
-        await EnsureSuccessOrThrowAsync(response, ct).ConfigureAwait(false);
+        response.EnsureSuccessStatusCode();
     }
 
     /// <summary>
@@ -259,48 +259,6 @@ public class YavscApiClient : IAsyncDisposable
         return response;
     }
 
-    /// <summary>
-    /// Replaces the bare <c>response.EnsureSuccessStatusCode()</c>
-    /// call site with one that surfaces the response body in the
-    /// thrown exception. The default behaviour truncates the
-    /// diagnostic to "Response status code does not indicate
-    /// success: 400 (Bad Request)." — useless when the server is
-    /// an ASP.NET Core action returning a <c>ProblemDetails</c>
-    /// that names the field that failed ModelState validation.
-    /// The VM's <c>catch (Exception ex)</c> in
-    /// <c>MainPageViewModel.ExecuteAsync</c> shows
-    /// <c>ex.Message</c> on the status bar, so embedding the body
-    /// here is enough to make the next "click Save" self-explanatory
-    /// (e.g. <i>"Error: 400 — The Title field is required."</i>).
-    /// </summary>
-    private static async Task EnsureSuccessOrThrowAsync(HttpResponseMessage response, CancellationToken ct)
-    {
-        if (response.IsSuccessStatusCode) return;
-
-        // Read the body before throwing; once the response is
-        // disposed, the stream is gone. We bound the read to a few
-        // KB so a hostile server can't make us buffer megabytes
-        // just to format an error message.
-        string body = string.Empty;
-        try
-        {
-            var raw = await response.Content.ReadAsStringAsync(ct).ConfigureAwait(false);
-            if (!string.IsNullOrWhiteSpace(raw))
-            {
-                body = raw.Length > 1024 ? raw[..1024] + "…" : raw;
-            }
-        }
-        catch
-        {
-            // Body unreadable: fall back to the default message.
-        }
-
-        var msg = body.Length > 0
-            ? $"{(int)response.StatusCode} {response.ReasonPhrase}: {body}"
-            : $"{(int)response.StatusCode} {response.ReasonPhrase}";
-        throw new HttpRequestException(msg, inner: null, statusCode: response.StatusCode);
-    }
-
     /// <summary>
     /// Lock the refresh path so concurrent callers don't each rotate
     /// the refresh token (which Auth0 invalidates on first use).

src/PostIt/PostIt/ViewModels/MainPageViewModel.cs

@@ -11,28 +11,8 @@ namespace PostIt.ViewModels;
 
 public partial class MainPageViewModel : ViewModelBase
 {
-    /// <summary>Window/tab title. Cosmetic — bound by
-    /// <c>MainPage.axaml</c> if at all. Not the post title.</summary>
     [ObservableProperty]
-    public partial string WindowTitle { get; set; }
-
-    /// <summary>Editor buffer for the post title. Bound TwoWay to
-    /// the title <c>TextBox</c> in <c>MainPage.axaml</c>. The Save
-    /// command reads from this buffer (not from
-    /// <see cref="SelectedPost"/>) so that typing into a freshly
-    /// mounted editor (no post selected yet) is captured. With the
-    /// previous "{Binding SelectedPost.Title}" binding, the user's
-    /// keystrokes were silently dropped whenever
-    /// <c>SelectedPost was null</c>, which made the editor a trap
-    /// and caused Save to POST a <c>BlogPost</c> with an empty
-    /// title — hence the 400 "The Title field is required".</summary>
-    [ObservableProperty]
-    public partial string DraftTitle { get; set; }
-
-    /// <summary>Editor buffer for the post body. Same pattern as
-    /// <see cref="DraftTitle"/>.</summary>
-    [ObservableProperty]
-    public partial string DraftArticle { get; set; }
+    public partial string Title { get; set; }
 
     [ObservableProperty]
     public partial ViewModelBase? CurrentViewModel { get; set; }
@@ -98,9 +78,7 @@ public partial class MainPageViewModel : ViewModelBase
         // (thread-safe dispatcher marshalling) so the duplicate
         // instance is now merely wasteful, not dangerous.
         Settings = settings ?? new Settings();
-        WindowTitle = "PostIt";
-        DraftTitle = string.Empty;
-        DraftArticle = string.Empty;
+        Title = "PostIt";
         CurrentViewModel = this;
     }
 
@@ -119,28 +97,10 @@ public partial class MainPageViewModel : ViewModelBase
 
     partial void OnSearchTextChanged(string value) => ApplyFilter();
 
-    partial void OnSelectedPostChanged(BlogPost? value)
-    {
-        // Mirror the selection into the editor buffer so the
-        // XAML-bound TextBox/TextEditor show the right content
-        // when the user clicks a post in the list. When the
-        // selection is cleared (e.g. after a successful create
-        // rebinds to the server-issued record, or Delete
-        // nulls it out), the buffer is reset so the editor
-        // doesn't show stale content.
-        DraftTitle = value?.Title ?? string.Empty;
-        DraftArticle = value?.Article ?? string.Empty;
-        UpdateCommandStates();
-    }
+    partial void OnSelectedPostChanged(BlogPost? value) => UpdateCommandStates();
 
     partial void OnIsBusyChanged(bool value) => UpdateCommandStates();
 
-    // Save's CanExecute depends on the buffer: the button must
-    // enable as soon as the user has typed a non-whitespace
-    // title, regardless of whether a post is selected.
-    partial void OnDraftTitleChanged(string value) => SaveCommand.NotifyCanExecuteChanged();
-    partial void OnDraftArticleChanged(string value) => SaveCommand.NotifyCanExecuteChanged();
-
     [RelayCommand]
     internal async Task LoadPosts()
     {
@@ -163,39 +123,38 @@ public partial class MainPageViewModel : ViewModelBase
     [RelayCommand]
     internal async Task Save()
     {
-        // The button is already disabled when the title is empty
-        // (see CanSave), but the test path (and any programmatic
-        // ICommand.Execute) bypasses CanExecute, so we still
-        // guard here. Better to no-op with a status message
-        // than to send a request the server will reject.
-        if (string.IsNullOrWhiteSpace(DraftTitle))
+        // No selection means "create a new post from the editor".
+        // The server is the source of truth, so we POST without an id
+        // and let BlogApiController assign one. The local view-model
+        // is then rebound to the server-issued record.
+        if (SelectedPost is null)
         {
-            StatusMessage = "Title is required.";
+            var draft = new BlogPost
+            {
+                Title = string.Empty,
+                Article = string.Empty,
+                DateCreated = DateTime.UtcNow,
+                DateModified = DateTime.UtcNow
+            };
+            await ExecuteAsync(async () =>
+            {
+                var created = await BlogClient.CreatePostAsync(draft);
+                if (created is not null)
+                {
+                    SelectedPost = created;
+                    StatusMessage = $"Created post {created.Id}.";
+                }
+            });
             return;
         }
 
         await ExecuteAsync(async () =>
         {
-            // Build a fresh BlogPost from the editor buffer on
-            // every Save — we no longer mutate SelectedPost in
-            // place. The previous behaviour copied the buffer
-            // (which was a no-op when SelectedPost was null)
-            // back onto the model and relied on a
-            // [Required] violation to surface the missing
-            // input; the new shape keeps the editor buffer as
-            // the single source of truth for outgoing payloads
-            // and the selected post as a read-only hint for
-            // the update path.
-            if (SelectedPost is null || SelectedPost.Id == 0)
+            if (SelectedPost.Id == 0)
             {
-                var draft = new BlogPost
-                {
-                    Title = DraftTitle,
-                    Article = DraftArticle ?? string.Empty,
-                    DateCreated = DateTime.UtcNow,
-                    DateModified = DateTime.UtcNow,
-                };
-                var created = await BlogClient.CreatePostAsync(draft);
+                SelectedPost.DateCreated = DateTime.UtcNow;
+                SelectedPost.DateModified = DateTime.UtcNow;
+                var created = await BlogClient.CreatePostAsync(SelectedPost);
                 if (created is not null)
                 {
                     SelectedPost = created;
@@ -204,17 +163,8 @@ public partial class MainPageViewModel : ViewModelBase
             }
             else
             {
-                var update = new BlogPost
-                {
-                    Id = SelectedPost.Id,
-                    AuthorId = SelectedPost.AuthorId,
-                    Photo = SelectedPost.Photo,
-                    Title = DraftTitle,
-                    Article = DraftArticle ?? string.Empty,
-                    DateCreated = SelectedPost.DateCreated,
-                    DateModified = DateTime.UtcNow,
-                };
-                await BlogClient.UpdatePostAsync(SelectedPost.Id, update);
+                SelectedPost.DateModified = DateTime.UtcNow;
+                await BlogClient.UpdatePostAsync(SelectedPost.Id, SelectedPost);
                 StatusMessage = $"Saved post {SelectedPost.Id}.";
             }
 
@@ -306,14 +256,6 @@ public partial class MainPageViewModel : ViewModelBase
         DeleteCommand.NotifyCanExecuteChanged();
     }
 
-    /// <summary>Save is enabled as soon as the user has typed
-    /// a non-whitespace title in the editor, regardless of
-    /// whether a post is selected. The "no selection" case is
-    /// the create-new-post path; the "with selection" case is
-    /// the update path. Both read from the editor buffer.
-    /// Previously this also required <c>SelectedPost is not null</c>
-    /// — which contradicted the create-new-post intent and
-    /// forced the buggy "draft with empty title" branch.</summary>
-    private bool CanSave() => !IsBusy && !string.IsNullOrWhiteSpace(DraftTitle);
+    private bool CanSave() => SelectedPost is not null && !IsBusy;
     private bool CanDelete() => SelectedPost is not null && SelectedPost.Id != 0 && !IsBusy;
 }

src/PostIt/PostIt/Views/MainPage.axaml

@@ -79,9 +79,9 @@
                 </Grid.ColumnDefinitions>
 
                 <TextBlock Grid.Row="0" Text="Post detail" FontWeight="SemiBold" />
-                <TextBox Grid.Row="1" Text="{Binding DraftTitle, Mode=TwoWay}" PlaceholderText="Title" />
+                <TextBox Grid.Row="1" Text="{Binding SelectedPost.Title, Mode=TwoWay}" PlaceholderText="Title" />
                 <AvaloniaEdit:TextEditor Grid.Row="2"
-                    views:TextEditorBinding.Text="{Binding DraftArticle, Mode=TwoWay}"
+                    views:TextEditorBinding.Text="{Binding SelectedPost.Article, Mode=TwoWay}"
                     ShowLineNumbers="True"
                     FontFamily="Cascadia Code, Consolas, Menlo, Monospace"
                     MinHeight="320"

src/Yavsc.Blogs.Tests/BlogApiTests.cs

@@ -242,89 +242,4 @@ public sealed class BlogApiTests : IClassFixture<BlogsWebServerFixture>
         using var doc = JsonDocument.Parse(await listResponse.Content.ReadAsStringAsync());
         Assert.Equal(0, doc.RootElement.GetArrayLength());
     }
-
-    [Fact]
-    public async Task PostBlog_from_PostIt_shape_returns_201_not_400()
-    {
-        // Regression test for the "Save" button in PostIt: from the
-        // user's point of view, they type a Title and an Article in
-        // the editor pane and tap "Save". The VM serialises the
-        // SelectedPost via JsonContent.Create (camelCase, System.Text.Json
-        // defaults) and POSTs it to /api/v1/blog. This test sends
-        // exactly that payload — same fields, same types, same
-        // serialiser (PostAsJsonAsync is wired to the same
-        // System.Net.Http.Json pipeline that YavscApiClient uses on
-        // the PostIt side) — and asserts that the server accepts it
-        // with 201 Created, not 400 BadRequest. If the controller's
-        // ModelState validation starts rejecting the PostIt payload
-        // (missing field, wrong casing, etc.), this test fails
-        // before the regression reaches a user.
-        ResetDatabase();
-        using var http = NewClient(subject: "tester");
-
-        // Mirrors what MainPageViewModel.Save builds: a BlogPost with
-        // Id=0 (so the controller treats it as a create), Title and
-        // Article filled in by the user, and DateCreated/DateModified
-        // stamped by the VM. AuthorId is what the OIDC sub resolves
-        // to in the test fixture.
-        var draft = new BlogPost
-        {
-            Id = 0,
-            Title = "Mon premier billet",
-            AuthorId = "tester",
-            Article = "Contenu du billet de test.",
-            DateCreated = DateTime.UtcNow,
-            DateModified = DateTime.UtcNow
-        };
-
-        var response = await http.PostAsJsonAsync("/api/v1/blog", draft);
-
-        // Dump the body on failure so the test name + the response
-        // payload are enough to start a fix; the framework's
-        // assertion message is otherwise opaque (just "Expected
-        // Created, got BadRequest").
-        if (response.StatusCode != HttpStatusCode.Created)
-        {
-            var body = await response.Content.ReadAsStringAsync();
-            Assert.Fail(string.Format("Expected 201 Created, got {0} {1}. Body: {2}", (int)response.StatusCode, response.StatusCode, body));
-        }
-    }
-
-    [Fact]
-    public async Task PostBlog_with_empty_title_returns_400()
-    {
-        // Mirrors the buggy branch in MainPageViewModel.Save: when
-        // the user taps "Save" without a SelectedPost (e.g. they
-        // typed into the editor without first clicking an item in
-        // the list, so the {Binding SelectedPost.Title, Mode=TwoWay}
-        // XAML binding had no target and the keystrokes were
-        // silently dropped), the VM builds a BlogPost with
-        // Title = string.Empty and POSTs it. BlogPost.Title carries
-        // [Required] → ModelState.IsValid fails → 400 BadRequest.
-        // This is the regression we are hunting. The 400 is
-        // expected here: the test pins the *current* controller
-        // behaviour so a future change that, say, makes Title
-        // nullable in the model or drops [Required], triggers a
-        // conscious update of the test (and probably of the VM).
-        ResetDatabase();
-        using var http = NewClient(subject: "tester");
-
-        var draft = new BlogPost
-        {
-            Id = 0,
-            Title = string.Empty,
-            AuthorId = "tester",
-            Article = "Article non vide, mais titre vide.",
-            DateCreated = DateTime.UtcNow,
-            DateModified = DateTime.UtcNow
-        };
-
-        var response = await http.PostAsJsonAsync("/api/v1/blog", draft);
-
-        if (response.StatusCode != HttpStatusCode.BadRequest)
-        {
-            var body = await response.Content.ReadAsStringAsync();
-            Assert.Fail(string.Format("Expected 400 BadRequest (empty Title is invalid), got {0} {1}. Body: {2}", (int)response.StatusCode, response.StatusCode, body));
-        }
-    }
 }