Add Atom 1.0 feed syndication

PancakesWeb/Controllers/FeedController.cs

@@ -0,0 +1,48 @@
+using System.Net.Mime;
+using System.ServiceModel.Syndication;
+using System.Xml;
+using Microsoft.AspNetCore.Mvc;
+using PancakesWeb.Components.UI;
+
+namespace PancakesWeb.Controllers;
+
+[ApiController]
+public class FeedController : ControllerBase
+{
+    [HttpGet("/feed.atom")]
+    [Produces("application/atom+xml")]
+    public ContentResult GetAtomFeed()
+    {
+        var feed = new SyndicationFeed
+        {
+            Title = new TextSyndicationContent("pancakes' blog"),
+            Description = new TextSyndicationContent("🐈‍⬛"),
+            Id = "https://pancakes.gay/feed.atom",
+            BaseUri = new Uri("https://pancakes.gay/feed.atom"),
+            Authors = { new SyndicationPerson("p@pancakes.gay", "pancakes", "https://pancakes.gay") },
+            Items = BlogPosts.Posts.OrderByDescending(post => post.Published).Select(post =>
+                new SyndicationItem(post.Title, SyndicationContent.CreateHtmlContent(post.Content),
+                    new Uri($"https://pancakes.gay/{post.Slug}"), $"https://pancakes.gay/{post.Slug}",
+                    new DateTimeOffset(post.Edited ?? post.Published))
+                {
+                    Copyright = post.Footer is BlogPosts.PostFooter.CcBy
+                        ? new TextSyndicationContent(
+                            $"{post.Title} © {post.Published.Year} by pancakes is licensed under CC BY 4.0")
+                        : null,
+                    PublishDate = new DateTimeOffset(post.Published),
+                    Summary = new TextSyndicationContent(post.Description)
+                }),
+            Links =
+            {
+                SyndicationLink.CreateSelfLink(new Uri("https://pancakes.gay/feed.atom")),
+                SyndicationLink.CreateAlternateLink(new Uri("https://pancakes.gay"), MediaTypeNames.Text.Html),
+            }
+        };
+
+        var stringWriter = new StringWriter();
+        var writer = new XmlTextWriter(stringWriter);
+        feed.SaveAsAtom10(writer);
+
+        return Content(stringWriter.ToString(), "application/atom+xml");
+    }
+}

PancakesWeb/Data/Button.cs

@@ -187,6 +187,12 @@ public static class Buttons
         {
             Image = "wii.webp",
             Title = "Wii"
+        },
+        new Button
+        {
+            Image = "valid_atom.webp",
+            Title = "Valid Atom 1.0",
+            Href = "/feed.atom"
         }
     ];
 }

PancakesWeb/PancakesWeb.csproj

@@ -8,6 +8,7 @@
 
     <ItemGroup>
       <PackageReference Include="Markdig" Version="0.42.0" />
+      <PackageReference Include="System.ServiceModel.Syndication" Version="9.0.9" />
       <PackageReference Include="YamlDotNet" Version="16.3.0" />
     </ItemGroup>
 

PancakesWeb/Program.cs

@@ -6,6 +6,7 @@ var builder = WebApplication.CreateBuilder(args);
 builder.Services.AddRazorComponents()
     .AddInteractiveServerComponents();
 builder.Services.AddHttpClient();
+builder.Services.AddControllers();
 
 builder.Configuration.AddEnvironmentVariables();
 
@@ -32,5 +33,6 @@ app.UseAntiforgery();
 app.MapStaticAssets();
 app.MapRazorComponents<App>()
     .AddInteractiveServerRenderMode();
+app.MapControllers();
 
 app.Run();