Read the desk's page parameter as text so a bad value shows the first page

src/FluentCMS.Admin/Components/Pages/Desk.razor

@@ -223,8 +223,9 @@
     [SupplyParameterFromQuery(Name = "queue")]
     private string? QueueSlug { get; set; }
 
+    // Read as text, so a page that is not a number, or too large for one, shows the first page rather than failing the request.
     [SupplyParameterFromQuery(Name = "page")]
-    private int? PageNumber { get; set; }
+    private string? PageText { get; set; }
 
     // What the set view did before it came back here, because the queue it was reviewing is now empty.
     [SupplyParameterFromQuery(Name = "done")]
@@ -250,7 +251,7 @@
     {
         // An unknown queue shows the default one rather than an error, as a mistyped link would otherwise land nowhere.
         _queue = Slugs.FirstOrDefault(pair => pair.Value == QueueSlug).Key;
-        _page = Math.Max(1, PageNumber ?? 1);
+        _page = int.TryParse(PageText, NumberStyles.Integer, CultureInfo.InvariantCulture, out var page) ? Math.Max(1, page) : 1;
         _offset = (int)Math.Min((_page - 1L) * PageSize, int.MaxValue - PageSize);
 
         var counts = await Queues.CountAsync();

src/FluentCMS.Admin/Components/Pages/SecurityEventsView.razor

@@ -99,12 +99,13 @@ else
     private int _offset;
     private string? _error;
 
+    // Read as text, so a page that is not a number, or too large for one, shows the first page rather than failing the request.
     [SupplyParameterFromQuery(Name = "page")]
-    private int? PageNumber { get; set; }
+    private string? PageText { get; set; }
 
     protected override async Task OnInitializedAsync()
     {
-        _page = Math.Max(1, PageNumber ?? 1);
+        _page = int.TryParse(PageText, NumberStyles.Integer, CultureInfo.InvariantCulture, out var page) ? Math.Max(1, page) : 1;
         _offset = (int)Math.Min((_page - 1L) * PageSize, int.MaxValue - PageSize);
 
         var listed = await AuditLists.ListAsync(new AuditEventListQuery { Operations = SecurityEvents.Operations, Offset = _offset, Limit = PageSize });

tests/FluentCMS.IntegrationTests/Desk/DeskScreenTests.cs

@@ -62,6 +62,21 @@ public async Task The_desk_renders_right_to_left()
         Assert.Contains("data-testid=\"desk-queues\"", desk);
     }
 
+    [Fact]
+    public async Task A_page_that_is_not_a_number_shows_the_first_page()
+    {
+        using var install = new TemporaryInstall();
+        await using var host = await AdminHost.StartAsync(install);
+        await host.CreateFirstAdministratorAsync();
+        await host.SignInAsync(AdminHost.Owner);
+
+        foreach (var path in new[] { "/?queue=reverted&page=abc", "/?queue=reverted&page=99999999999", "/security?page=99999999999", "/security?page=abc" })
+        {
+            var response = await host.Client.GetAsync(path);
+            Assert.True(response.StatusCode == System.Net.HttpStatusCode.OK, $"{path}: {(int)response.StatusCode}");
+        }
+    }
+
     private static async Task<Guid> AwaitingReviewAsync(AdminHost host, Guid userId, string slug)
     {
         var type = await host.AsUserAsync<IContentTypeDirectory, ContentType>(userId, async directory =>

tests/FluentCMS.Tests/Admin/DeskTests.cs

@@ -111,6 +111,9 @@ public void The_queue_and_page_come_from_the_address()
     [InlineData("/?queue=nonsense", DeskQueue.AwaitingMe, 0)]
     [InlineData("/?queue=reverted&page=0", DeskQueue.Reverted, 0)]
     [InlineData("/?queue=reverted&page=-3", DeskQueue.Reverted, 0)]
+    [InlineData("/?queue=reverted&page=abc", DeskQueue.Reverted, 0)]
+    [InlineData("/?queue=reverted&page=99999999999", DeskQueue.Reverted, 0)]
+    [InlineData("/?queue=reverted&page=", DeskQueue.Reverted, 0)]
     public void An_unknown_queue_or_page_falls_back_to_the_first(string address, DeskQueue queue, int offset)
     {
         var queues = new FakeQueues();

tests/FluentCMS.Tests/Admin/SecurityEventsViewTests.cs

@@ -50,6 +50,21 @@ public void The_page_comes_from_the_address_and_links_to_its_neighbours()
         Assert.Equal("security?page=3", cut.Find("a[rel=next]").GetAttribute("href"));
     }
 
+    [Theory]
+    [InlineData("/security?page=abc")]
+    [InlineData("/security?page=99999999999")]
+    [InlineData("/security?page=")]
+    public void A_page_that_is_not_a_number_shows_the_first(string address)
+    {
+        var lists = new FakeLists { Total = 160 };
+        using var context = Context(lists);
+        context.Services.GetRequiredService<NavigationManager>().NavigateTo(address);
+
+        context.Render<SecurityEventsView>();
+
+        Assert.Equal(0, lists.Queries[0].Offset);
+    }
+
     [Fact]
     public void An_empty_log_says_so()
     {