Use YAML parser

zotan.pw-web/Pages/blog/Blog.cshtml.cs

@@ -1,40 +1,80 @@
+using System.Diagnostics.CodeAnalysis;
 using System.Text.RegularExpressions;
 using Markdig;
+using Markdig.Extensions.Yaml;
+using Markdig.Renderers;
+using Markdig.Syntax;
 using Microsoft.AspNetCore.Mvc.RazorPages;
+using YamlDotNet.Serialization;
+using YamlDotNet.Serialization.NamingConventions;
 
 namespace zotanpw_web.Pages.blog;
 
 public class BlogModel : PageModel {
-	public static readonly List<BlogPost> Posts = new() {
-		new BlogPost("adhd-and-notes", "ADHD & Notetaking: an autistic perspective", DateOnly.Parse("2021-08-07")),
-		new BlogPost("ipv6-networking", "IPv6-native networking: a project report", DateOnly.Parse("2021-08-23"))
-	};
+	public static readonly List<BlogPost> Posts = new();
 
 	static BlogModel() {
+		foreach (var file in Directory.EnumerateFiles("Pages/blog/posts"))
+			Posts.Add(new BlogPost(Path.GetFileNameWithoutExtension(file)));
+
 		Posts = Posts.OrderByDescending(p => p.PublishedOn).ToList();
 	}
 
 	public void OnGet() { }
 
 	public class BlogPost {
-		public readonly DateOnly PublishedOn;
 		public readonly string Shorthand;
-		public readonly string   Title;
 		public          string Content = "";
-		public          int      ReadTimeMinutes;
 
-		public BlogPost(string shorthand, string title, DateOnly publishedOn) {
-			Title       = title;
-			PublishedOn = publishedOn;
+		public DateOnly PublishedOn;
+		public int      ReadTimeMinutes;
+		public string   Title = null!;
+
+		public BlogPost(string shorthand) {
 			Shorthand = shorthand;
-			UpdateContent();
+			UpdateContentAndMetadata();
 		}
 
-		public void UpdateContent() {
+		public void UpdateContentAndMetadata() {
 			var markdownText = System.IO.File.ReadAllText($"Pages/blog/posts/{Shorthand}.md");
 
-			Content         = Markdown.ToHtml(markdownText, new MarkdownPipelineBuilder().UseGenericAttributes().Build());
+			var parsed = ParseBlogPost(markdownText);
+			Title           = parsed.metadata.Title!;
+			PublishedOn     = parsed.metadata.Date;
 			ReadTimeMinutes = Regex.Matches(markdownText, @"\b\w+\b").Count / 150;
+			Content         = parsed.html;
+		}
+
+		private static (PostMetadata metadata, string html) ParseBlogPost(string markdown) {
+			var yaml = "";
+
+			var pipeline = new MarkdownPipelineBuilder().UseGenericAttributes().UseYamlFrontMatter().Build();
+			var writer   = new StringWriter();
+			var renderer = new HtmlRenderer(writer);
+			pipeline.Setup(renderer);
+
+			var document  = Markdown.Parse(markdown, pipeline);
+			var yamlBlock = document.Descendants<YamlFrontMatterBlock>().FirstOrDefault();
+
+			if (yamlBlock != null)
+				yaml = markdown.Substring(yamlBlock.Span.Start, yamlBlock.Span.Length);
+
+			renderer.Render(document);
+			writer.Flush();
+			var html = writer.ToString();
+
+			var yamlDeserializer = new DeserializerBuilder().WithNamingConvention(LowerCaseNamingConvention.Instance).Build();
+			var metadata         = yamlDeserializer.Deserialize<PostMetadata>(yaml);
+
+			return (metadata, html);
+		}
+
+		[SuppressMessage("ReSharper", "ClassNeverInstantiated.Local")]
+		private class PostMetadata {
+			#pragma warning disable CS0649
+			public string?  Title;
+			public DateOnly Date;
+			#pragma warning restore CS0649
 		}
 	}
 }

zotan.pw-web/Pages/blog/BlogPost.cshtml

@@ -12,7 +12,7 @@
 	ViewData["title"] = "blog";
 	ViewData["subtitle"] = post.Shorthand;
 	#if (DEBUG)
-	post.UpdateContent();
+	post.UpdateContentAndMetadata();
 	#endif
 }
 

zotan.pw-web/Pages/blog/posts/adhd-and-notes.md

@@ -1,3 +1,7 @@
+---
+title: "ADHD & Notetaking: an autistic perspective"
+date: 2021-08-07
+...
 If you are living with ADHD, diagnosed or not, the following things
 might sound familiar: *"I forgot to write that down"*, *"I forgot to do
 that"*, *"I don't remember that"*.

zotan.pw-web/Pages/blog/posts/ipv6-networking.md

@@ -1,3 +1,7 @@
+---
+title: "IPv6-native networking: a project report"
+date: 2021-08-23
+...
 If you have reached this post, chances are you already know my [AS211579](https://zotan.network){target="_blank"}
 project.
 This post serves as a summary of the things I learnt and the roadblocks

zotan.pw-web/Travelynx/Travelynx.cs

@@ -18,7 +18,7 @@ public class Travelynx : Controller {
 				db.InsertWithIdentity(new TravelynxInfo { CheckedIn = false });
 
 			var status = db.TravelynxInfo.First();
-			status.CheckedIn   = rq.Status.CheckedIn;
+			status.CheckedIn   = rq.Status!.CheckedIn;
 			status.Train       = $"{rq.Status.Train?.Type} {rq.Status.Train?.No}";
 			status.Destination = rq.Status.ToStation?.Name;
 			db.Update(status);

zotan.pw-web/Travelynx/WebhookRequest.cs

@@ -1,8 +1,8 @@
 namespace zotanpw_web.Travelynx;
 
 public class WebhookRequest {
-	public string Reason { get; set; }
-	public Status Status { get; set; }
+	public string? Reason { get; set; }
+	public Status? Status { get; set; }
 }
 
 public class Status {

zotan.pw-web/wwwroot/files/help.svg

@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<svg xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" width="500mm" height="400mm"
+<svg xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/"
+     xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" width="500mm" height="400mm"
      version="1.1" viewBox="0 0 500 400"
      xmlns="http://www.w3.org/2000/svg">
     <metadata>

zotan.pw-web/zotan.pw-web.csproj

@@ -66,6 +66,7 @@
         <PackageReference Include="Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation" Version="7.0.0"/>
         <PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="7.0.0"/>
         <PackageReference Include="System.Data.SQLite" Version="1.0.115"/>
+        <PackageReference Include="YamlDotNet" Version="12.0.2"/>
     </ItemGroup>
 
     <ItemGroup>