Add support for release-date field

Author: cotti

docs/cli/changelog/bundle.md

@@ -388,6 +388,25 @@ docs-builder changelog bundle \
   --description "Elasticsearch {version} includes performance improvements. Download: https://github.com/{owner}/{repo}/releases/tag/v{version}"
 ```
 
+### Bundle with release date
+
+You can add a `release-date` field directly to a bundle YAML file. This field is optional and purely informative for end-users. It is especially useful for components released outside the usual stack lifecycle, such as APM agents and EDOT agents.
+
+```yaml
+products:
+  - product: apm-agent-dotnet
+    target: 1.34.0
+release-date: "April 9, 2026"
+description: |
+  This release includes tracing improvements and bug fixes.
+entries:
+  - file:
+      name: tracing-improvement.yaml
+      checksum: abc123
+```
+
+When the bundle is rendered (by the `changelog render` command or `{changelog}` directive), the release date appears immediately after the version heading as italicized text: `_Released: April 9, 2026_`.
+
 ## Profile-based examples
 
 When the changelog configuration file defines `bundle.profiles`, you can use those profiles with the `changelog bundle` command.

docs/syntax/changelog.md

@@ -142,10 +142,11 @@ For full syntax, refer to the [rules for filtered bundles](/cli/changelog/bundle
 When bundles contain a `hide-features` field, entries with matching `feature-id` values are automatically filtered out from the rendered output. This allows you to hide unreleased or experimental features without modifying the bundle at render time.
 
 ```yaml
-# Example bundle with description and hide-features
+# Example bundle with release-date, description, and hide-features
 products:
   - product: elasticsearch
     target: 9.3.0
+release-date: "2026-04-09"
 description: |
   This release includes new features and bug fixes.
   
@@ -227,11 +228,13 @@ The version is extracted from the first product's `target` field in each bundle
 
 ## Rendered output
 
-Each bundle renders as a `## {version}` section with optional description and subsections beneath:
+Each bundle renders as a `## {version}` section with optional release date, description, and subsections beneath:
 
 ```markdown
 ## 0.100.0
 
+_Released: 2026-04-09_
+
 This release includes new features and bug fixes.
 
 Download the release binaries: https://github.com/elastic/elasticsearch/releases/tag/v0.100.0
@@ -246,7 +249,9 @@ Download the release binaries: https://github.com/elastic/elasticsearch/releases
 ...
 ```
 
-Bundle descriptions are rendered when present in the bundle YAML file. The description appears immediately after the version heading but before any entry sections. Descriptions support Markdown formatting including links, lists, and multiple paragraphs.
+When present, the `release-date` field is rendered immediately after the version heading as italicized text (e.g., `_Released: 2026-04-09_`). This is purely informative for end-users and is especially useful for components released outside the usual stack lifecycle, such as APM agents and EDOT agents.
+
+Bundle descriptions are rendered when present in the bundle YAML file. The description appears after the release date (if any) but before any entry sections. Descriptions support Markdown formatting including links, lists, and multiple paragraphs.
 
 ### Section types
 

src/Elastic.Documentation.Configuration/ReleaseNotes/Bundle.cs

@@ -18,6 +18,12 @@ public sealed record BundleDto
 	/// </summary>
 	public string? Description { get; set; }
 	/// <summary>
+	/// Optional release date for this bundle.
+	/// Purely informative; rendered after the release heading.
+	/// </summary>
+	[YamlMember(Alias = "release-date", ApplyNamingConventions = false)]
+	public string? ReleaseDate { get; set; }
+	/// <summary>
 	/// Feature IDs that should be hidden when rendering this bundle.
 	/// Entries with matching feature-id values will be commented out in the output.
 	/// </summary>

src/Elastic.Documentation.Configuration/ReleaseNotes/BundleLoader.cs

@@ -229,7 +229,19 @@ private static LoadedBundle MergeBundleGroup(IGrouping<string, LoadedBundle> gro
 			_ => string.Join("\n\n", descriptions)
 		};
 
-		var mergedData = first.Data with { Description = mergedDescription };
+		var releaseDates = bundlesList
+			.Select(b => b.Data?.ReleaseDate)
+			.Where(d => !string.IsNullOrEmpty(d))
+			.Distinct()
+			.ToList();
+
+		var mergedReleaseDate = releaseDates.Count switch
+		{
+			0 => null,
+			_ => releaseDates[0]
+		};
+
+		var mergedData = first.Data with { Description = mergedDescription, ReleaseDate = mergedReleaseDate };
 
 		return new LoadedBundle(
 			first.Version,

src/Elastic.Documentation.Configuration/ReleaseNotes/ReleaseNotesSerialization.cs

@@ -136,6 +136,7 @@ public static string SerializeBundle(Bundle bundle)
 	{
 		Products = dto.Products?.Select(ToBundledProduct).ToList() ?? [],
 		Description = dto.Description,
+		ReleaseDate = dto.ReleaseDate,
 		HideFeatures = dto.HideFeatures ?? [],
 		Entries = dto.Entries?.Select(ToBundledEntry).ToList() ?? []
 	};
@@ -241,6 +242,7 @@ private static ChangelogEntryType ParseEntryType(string? value)
 	{
 		Products = bundle.Products.Select(ToDto).ToList(),
 		Description = bundle.Description,
+		ReleaseDate = bundle.ReleaseDate,
 		HideFeatures = bundle.HideFeatures.Count > 0 ? bundle.HideFeatures.ToList() : null,
 		Entries = bundle.Entries.Select(ToDto).ToList()
 	};

src/Elastic.Documentation/ReleaseNotes/Bundle.cs

@@ -19,6 +19,13 @@ public record Bundle
 	/// </summary>
 	public string? Description { get; init; }
 
+	/// <summary>
+	/// Optional release date for this bundle.
+	/// Purely informative for end-users; rendered after the release heading.
+	/// Useful for components released outside the usual stack lifecycle (e.g., APM/EDOT agents).
+	/// </summary>
+	public string? ReleaseDate { get; init; }
+
 	/// <summary>
 	/// Feature IDs that should be hidden when rendering this bundle.
 	/// Entries with matching feature-id values will be commented out in the output.

src/Elastic.Markdown/Myst/Directives/Changelog/ChangelogInlineRenderer.cs

@@ -79,7 +79,7 @@ private static string RenderSingleBundle(
 		};
 
 		var displayVersion = VersionOrDate.FormatDisplayVersion(bundle.Version);
-		return GenerateMarkdown(displayVersion, titleSlug, bundle.Repo, bundle.Owner, entriesByType, subsections, hideLinks, typeFilter, publishBlocker, bundle.Data?.Description);
+		return GenerateMarkdown(displayVersion, titleSlug, bundle.Repo, bundle.Owner, entriesByType, subsections, hideLinks, typeFilter, publishBlocker, bundle.Data?.Description, bundle.Data?.ReleaseDate);
 	}
 
 	/// <summary>
@@ -153,7 +153,8 @@ private static string GenerateMarkdown(
 		bool hideLinks,
 		ChangelogTypeFilter typeFilter,
 		PublishBlocker? publishBlocker,
-		string? description = null)
+		string? description = null,
+		string? releaseDate = null)
 	{
 		var sb = new StringBuilder();
 
@@ -177,6 +178,13 @@ private static string GenerateMarkdown(
 
 		_ = sb.AppendLine(CultureInfo.InvariantCulture, $"## {title}");
 
+		// Add release date if present
+		if (!string.IsNullOrEmpty(releaseDate))
+		{
+			_ = sb.AppendLine();
+			_ = sb.AppendLine(CultureInfo.InvariantCulture, $"_Released: {releaseDate}_");
+		}
+
 		// Add description if present
 		if (!string.IsNullOrEmpty(description))
 		{

src/services/Elastic.Changelog/Rendering/Asciidoc/ChangelogAsciidocRenderer.cs

@@ -32,6 +32,13 @@ public async Task RenderAsciidoc(ChangelogRenderContext context, Cancel ctx)
 		_ = sb.AppendLine(InvariantCulture, $"== {context.Title}");
 		_ = sb.AppendLine();
 
+		// Add release date if present
+		if (!string.IsNullOrEmpty(context.BundleReleaseDate))
+		{
+			_ = sb.AppendLine(InvariantCulture, $"_Released: {context.BundleReleaseDate}_");
+			_ = sb.AppendLine();
+		}
+
 		// Add description if present
 		if (!string.IsNullOrEmpty(context.BundleDescription))
 		{

src/services/Elastic.Changelog/Rendering/ChangelogRenderContext.cs

@@ -30,4 +30,9 @@ public record ChangelogRenderContext
 	/// Optional bundle-level introductory description. Only set when there's a single bundle with a description (MVP approach).
 	/// </summary>
 	public string? BundleDescription { get; init; }
+	/// <summary>
+	/// Optional release date for this bundle. Purely informative for end-users.
+	/// Only set when there's a single bundle with a release date (MVP approach).
+	/// </summary>
+	public string? BundleReleaseDate { get; init; }
 }

src/services/Elastic.Changelog/Rendering/ChangelogRenderingService.cs

@@ -152,8 +152,26 @@ Cancel ctx
 				renderDescription = bundleDescriptions[0];
 			}
 
+			// Extract release dates from bundles for MVP support
+			var bundleReleaseDates = validationResult.Bundles
+				.Select(b => b.Data.ReleaseDate)
+				.Where(d => !string.IsNullOrEmpty(d))
+				.ToList();
+
+			string? renderReleaseDate = null;
+			if (bundleReleaseDates.Count > 1)
+			{
+				collector.EmitWarning(string.Empty,
+					$"Multiple bundles contain release dates ({bundleReleaseDates.Count} found). " +
+					"Multi-bundle release date support is not yet implemented. Release dates will be skipped.");
+			}
+			else if (bundleReleaseDates.Count == 1)
+			{
+				renderReleaseDate = bundleReleaseDates[0];
+			}
+
 			// Build render context
-			var context = BuildRenderContext(input, outputSetup, resolvedResult, combinedHideFeatures, config, renderDescription);
+			var context = BuildRenderContext(input, outputSetup, resolvedResult, combinedHideFeatures, config, renderDescription, renderReleaseDate);
 
 			// Validate entry types
 			if (!ValidateEntryTypes(collector, resolvedResult.Entries, config.Types))
@@ -266,7 +284,8 @@ private static ChangelogRenderContext BuildRenderContext(
 		ResolvedEntriesResult resolved,
 		HashSet<string> featureIdsToHide,
 		ChangelogConfiguration? config,
-		string? description = null)
+		string? description = null,
+		string? releaseDate = null)
 	{
 		// Group entries by type
 		var entriesByType = resolved.Entries
@@ -308,7 +327,8 @@ private static ChangelogRenderContext BuildRenderContext(
 			EntryToOwner = entryToOwner,
 			EntryToHideLinks = entryToHideLinks,
 			Configuration = config,
-			BundleDescription = description
+			BundleDescription = description,
+			BundleReleaseDate = releaseDate
 		};
 	}