Implement sitemap (#828)

* WIP

* Output sitemap on .artifacts/assembly

* Remove duplicate entries and validate sitemap as per specs

* Send SitemapBuilder to its own class

* Add newline

---------

Co-authored-by: Jan Calanog <[email protected]>

Author: cotti

src/docs-assembler/Building/SitemapBuilder.cs

@@ -0,0 +1,61 @@
+// Licensed to Elasticsearch B.V under one or more agreements.
+// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+// See the LICENSE file in the project root for more information
+
+using System.IO.Abstractions;
+using System.Xml.Linq;
+using Elastic.Markdown.IO.Navigation;
+
+namespace Documentation.Assembler.Building;
+
+public class SitemapBuilder(IReadOnlyCollection<INavigationItem> navigationItems, IFileSystem fileSystem, IDirectoryInfo outputFolder)
+{
+	private static readonly Uri BaseUri = new("https://www.elastic.co");
+	private readonly IReadOnlyCollection<INavigationItem> _navigationItems = navigationItems;
+	private readonly IFileSystem _fileSystem = fileSystem;
+	private readonly IDirectoryInfo _outputFolder = outputFolder;
+
+	public void Generate()
+	{
+		var flattenedNavigationItems = GetNavigationItems(_navigationItems);
+
+		var doc = new XDocument()
+		{
+			Declaration = new XDeclaration("1.0", "utf-8", "yes"),
+		};
+
+		var root = new XElement(
+				"urlset",
+				new XAttribute("xlmns", "http://www.sitemaps.org/schemas/sitemap/0.9"),
+				flattenedNavigationItems
+					.OfType<FileNavigationItem>()
+					.Select(n => n.File.Url)
+					.Distinct()
+					.Select(u => new Uri(BaseUri, u))
+					.Select(u => new XElement("url", new XElement("loc", u)))
+			);
+
+		doc.Add(root);
+
+		using var fileStream = _fileSystem.File.Create(Path.Combine(_outputFolder.ToString() ?? string.Empty, "sitemap.xml"));
+		doc.Save(fileStream);
+	}
+
+	private static IReadOnlyCollection<INavigationItem> GetNavigationItems(IReadOnlyCollection<INavigationItem> items)
+	{
+		var result = new List<INavigationItem>();
+		foreach (var item in items)
+		{
+			switch (item)
+			{
+				case FileNavigationItem file:
+					result.Add(file);
+					break;
+				case GroupNavigationItem group:
+					result.AddRange(GetNavigationItems(group.Group.NavigationItems));
+					break;
+			}
+		}
+		return result;
+	}
+}

src/docs-assembler/Cli/RepositoryCommands.cs

@@ -12,6 +12,7 @@
 using Documentation.Assembler.Sourcing;
 using Elastic.Documentation.Tooling.Diagnostics.Console;
 using Elastic.Markdown.CrossLinks;
+using Elastic.Markdown.IO.Navigation;
 using Microsoft.Extensions.Logging;
 
 namespace Documentation.Assembler.Cli;
@@ -77,7 +78,6 @@ public async Task<int> BuildAll(
 			Force = force ?? false,
 			AllowIndexing = allowIndexing ?? false,
 		};
-
 		var cloner = new AssemblerRepositorySourcer(logger, assembleContext);
 		var checkouts = cloner.GetAll().ToArray();
 		if (checkouts.Length == 0)
@@ -90,10 +90,13 @@ public async Task<int> BuildAll(
 
 		var pathProvider = new GlobalNavigationPathProvider(assembleSources, assembleContext);
 		var htmlWriter = new GlobalNavigationHtmlWriter(assembleContext, navigation, assembleSources);
-		var builder = new AssemblerBuilder(logger, assembleContext, htmlWriter, pathProvider);
 
+		var builder = new AssemblerBuilder(logger, assembleContext, htmlWriter, pathProvider);
 		await builder.BuildAllAsync(assembleSources.AssembleSets, ctx);
 
+		var sitemapBuilder = new SitemapBuilder(navigation.NavigationItems, assembleContext.WriteFileSystem, assembleContext.OutputDirectory);
+		sitemapBuilder.Generate();
+
 		if (strict ?? false)
 			return collector.Errors + collector.Warnings;
 		return collector.Errors;