Add initial support for page level annotations for product support

Author: Mpdreamz

src/Elastic.Markdown/Helpers/SemVersion.cs

@@ -92,6 +92,14 @@ public SemVersion(int major, int minor, int patch, string? prerelease, string? m
 		Metadata = metadata ?? string.Empty;
 	}
 
+	public static explicit operator SemVersion(string b)
+	{
+		var semVersion = TryParse(b, out var version) ? version : TryParse(b + ".0", out version) ? version : null;
+		return semVersion ?? throw new ArgumentException($"'{b}' is not a valid semver2 version string.");
+	}
+
+	public static implicit operator string(SemVersion d) => d.ToString();
+
 	/// <summary>
 	///
 	/// </summary>

src/Elastic.Markdown/Myst/FrontMatterParser.cs

@@ -1,6 +1,10 @@
 // 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 Elastic.Markdown.Helpers;
+using YamlDotNet.Core;
+using YamlDotNet.Core.Events;
 using YamlDotNet.Serialization;
 using YamlDotNet.Serialization.NamingConventions;
 
@@ -20,6 +24,43 @@ public class YamlFrontMatter
 
 	[YamlMember(Alias = "sub")]
 	public Dictionary<string, string>? Properties { get; set; }
+
+
+	[YamlMember(Alias = "applies")]
+	public DeploymentType? AppliesTo { get; set; }
+}
+
+[YamlSerializable]
+public class DeploymentType
+{
+	[YamlMember(Alias = "self")]
+	public SelfManagedDeployment? SelfManaged { get; set; }
+
+	[YamlMember(Alias = "cloud")]
+	public CloudManagedDeployment? Cloud { get; set; }
+}
+
+[YamlSerializable]
+public class SelfManagedDeployment
+{
+	[YamlMember(Alias = "stack")]
+	public SemVersion? Stack { get; set; }
+
+	[YamlMember(Alias = "ece")]
+	public SemVersion? Ece { get; set; }
+
+	[YamlMember(Alias = "eck")]
+	public SemVersion? Eck { get; set; }
+}
+
+[YamlSerializable]
+public class CloudManagedDeployment
+{
+	[YamlMember(Alias = "ess")]
+	public SemVersion? Ess { get; set; }
+
+	[YamlMember(Alias = "serverless")]
+	public SemVersion? Serverless { get; set; }
 }
 
 public static class FrontMatterParser
@@ -30,10 +71,29 @@ public static YamlFrontMatter Deserialize(string yaml)
 
 		var deserializer = new StaticDeserializerBuilder(new YamlFrontMatterStaticContext())
 			.IgnoreUnmatchedProperties()
+			.WithTypeConverter(new SemVersionConverter())
 			.Build();
 
 		var frontMatter = deserializer.Deserialize<YamlFrontMatter>(input);
 		return frontMatter;
 
 	}
 }
+
+public class SemVersionConverter : IYamlTypeConverter
+{
+	public bool Accepts(Type type) => type == typeof(SemVersion);
+
+	public object? ReadYaml(IParser parser, Type type, ObjectDeserializer rootDeserializer)
+	{
+		var value = parser.Consume<Scalar>();
+		return (SemVersion)value.Value;
+	}
+
+	public void WriteYaml(IEmitter emitter, object? value, Type type, ObjectSerializer serializer)
+	{
+		if (value == null)
+			return;
+		emitter.Emit(new Scalar(value.ToString()!));
+	}
+}

tests/Elastic.Markdown.Tests/FrontMatter/ProductConstraintTests.cs

@@ -0,0 +1,43 @@
+// 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 Elastic.Markdown.Helpers;
+using Elastic.Markdown.Tests.Directives;
+using FluentAssertions;
+using Xunit.Abstractions;
+
+namespace Elastic.Markdown.Tests.FrontMatter;
+
+public class ProductConstraintTests(ITestOutputHelper output) : DirectiveTest(output,
+"""
+---
+title: Elastic Docs v3
+navigation_title: "Documentation Guide"
+applies:
+  self:
+    stack: 7.7
+  cloud:
+    serverless: 1.0.0
+---
+"""
+)
+{
+	[Fact]
+	public void ReadsTitle() => File.Title.Should().Be("Elastic Docs v3");
+
+	[Fact]
+	public void ReadsNavigationTitle() => File.NavigationTitle.Should().Be("Documentation Guide");
+
+	[Fact]
+	public void ReadsSubstitutions()
+	{
+		File.YamlFrontMatter.Should().NotBeNull();
+		var appliesTo = File.YamlFrontMatter!.AppliesTo;
+		appliesTo.Should().NotBeNull();
+		appliesTo!.SelfManaged.Should().NotBeNull();
+		appliesTo.Cloud.Should().NotBeNull();
+		appliesTo.Cloud!.Serverless.Should().BeEquivalentTo(new SemVersion(1,0,0));
+	}
+}
+

tests/Elastic.Markdown.Tests/Directives/YamlFrontMatterTests.cs renamed to tests/Elastic.Markdown.Tests/FrontMatter/YamlFrontMatterTests.cs

@@ -1,10 +1,12 @@
 // 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 Elastic.Markdown.Tests.Directives;
 using FluentAssertions;
 using Xunit.Abstractions;
 
-namespace Elastic.Markdown.Tests.Directives;
+namespace Elastic.Markdown.Tests.FrontMatter;
 
 public class YamlFrontMatterTests(ITestOutputHelper output) : DirectiveTest(output,
 """