Add ability to set feature flags from assembler config (#1391)

* Add ability to set feature flags from assembler config

* Revert changes to _Footer.cshtml

Author: reakaleek

src/Elastic.Documentation.Configuration/Assembler/PublishEnvironment.cs

@@ -25,4 +25,7 @@ public record PublishEnvironment
 
 	[YamlMember(Alias = "google_tag_manager")]
 	public GoogleTagManager GoogleTagManager { get; set; } = new();
+
+	[YamlMember(Alias = "feature_flags")]
+	public Dictionary<string, bool> FeatureFlags { get; set; } = [];
 }

src/Elastic.Documentation.Configuration/Builder/FeatureFlags.cs

@@ -4,10 +4,28 @@
 
 namespace Elastic.Documentation.Configuration.Builder;
 
-public class FeatureFlags(Dictionary<string, bool> featureFlags)
+public class FeatureFlags(Dictionary<string, bool> initFeatureFlags)
 {
-	public bool IsPrimaryNavEnabled => IsEnabled("primary-nav");
-	public bool IsVersionDropdownEnabled => IsEnabled("version-dropdown");
+	private readonly Dictionary<string, bool> _featureFlags = new(initFeatureFlags);
+
+	public void Set(string key, bool value)
+	{
+		var normalizedKey = key.ToLowerInvariant().Replace('_', '-');
+		_featureFlags[normalizedKey] = value;
+	}
+
+	public bool PrimaryNavEnabled
+	{
+		get => IsEnabled("primary-nav");
+		set => _featureFlags["primary-nav"] = value;
+	}
+
+	public bool VersionDropdownEnabled
+	{
+		get => IsEnabled("version-dropdown");
+		set => _featureFlags["version-dropdown"] = value;
+	}
+
 	private bool IsEnabled(string key)
 	{
 		var envKey = $"FEATURE_{key.ToUpperInvariant().Replace('-', '_')}";
@@ -18,6 +36,7 @@ private bool IsEnabled(string key)
 			// if the env var is set but not a bool, we treat it as enabled
 			return true;
 		}
-		return featureFlags.TryGetValue(key, out var value) && value;
+
+		return _featureFlags.TryGetValue(key, out var value) && value;
 	}
 }

src/Elastic.Documentation.Site/Layout/_Header.cshtml

@@ -1,5 +1,5 @@
 @inherits RazorSlice<Elastic.Documentation.Site.GlobalLayoutViewModel>
-@if (Model.Features.IsPrimaryNavEnabled)
+@if (Model.Features.PrimaryNavEnabled)
 {
 	<div id="elastic-nav"></div>
 	<script src="https://www.elastic.co/elastic-nav.js"></script>

src/Elastic.Documentation.Site/Navigation/IsolatedBuildNavigationHtmlWriter.cs

@@ -14,7 +14,7 @@ public class IsolatedBuildNavigationHtmlWriter(BuildContext context, INodeNaviga
 
 	public async Task<string> RenderNavigation(INodeNavigationItem<INavigationModel, INavigationItem> currentRootNavigation, Uri navigationSource, Cancel ctx = default)
 	{
-		var navigation = context.Configuration.Features.IsPrimaryNavEnabled
+		var navigation = context.Configuration.Features.PrimaryNavEnabled
 			? currentRootNavigation
 			: siteRoot;
 
@@ -33,7 +33,7 @@ private NavigationViewModel CreateNavigationModel(INodeNavigationItem<INavigatio
 			Title = navigation.NavigationTitle,
 			TitleUrl = navigation.Url,
 			Tree = navigation,
-			IsPrimaryNavEnabled = context.Configuration.Features.IsPrimaryNavEnabled,
+			IsPrimaryNavEnabled = context.Configuration.Features.PrimaryNavEnabled,
 			IsGlobalAssemblyBuild = false,
 			TopLevelItems = siteRoot.NavigationItems.OfType<INodeNavigationItem<INavigationModel, INavigationItem>>().ToList()
 		};

src/Elastic.Markdown/Slices/Layout/_Breadcrumbs.cshtml

@@ -1,7 +1,7 @@
 @inherits RazorSlice<MarkdownLayoutViewModel>
 @{
 	var targets =
-		Model.Features.IsPrimaryNavEnabled
+		Model.Features.PrimaryNavEnabled
 			? Model.Parents.Reverse()
 			: Model.Parents.Reverse().Skip(1);
 

src/Elastic.Markdown/Slices/Layout/_TableOfContents.cshtml

@@ -1,7 +1,7 @@
 @inherits RazorSlice<MarkdownLayoutViewModel>
 <aside class="sidebar hidden lg:block max-w-65 md:hidden">
 	<nav id="toc-nav" class="sidebar-nav h-full">
-		@if (Model.Features.IsVersionDropdownEnabled)
+		@if (Model.Features.VersionDropdownEnabled)
 		{
 			<div class="mt-6">
 				<version-dropdown all-versions-url="@Model.AllVersionsUrl" current-version='@(Model.CurrentVersion)' items='@(new HtmlString(Model.VersionDropdownSerializedModel))' />

src/tooling/docs-assembler/Building/AssemblerBuilder.cs

@@ -30,6 +30,8 @@ public class AssemblerBuilder(
 	ILegacyUrlMapper? legacyUrlMapper
 )
 {
+	private readonly ILogger<AssemblerBuilder> _logger = logger.CreateLogger<AssemblerBuilder>();
+
 	private GlobalNavigationHtmlWriter HtmlWriter { get; } = writer;
 
 	private ILegacyUrlMapper? LegacyUrlMapper { get; } = legacyUrlMapper;
@@ -118,6 +120,7 @@ string Resolve(string relativeMarkdownPath)
 
 	private async Task<GenerationResult> BuildAsync(AssemblerDocumentationSet set, bool noop, IMarkdownExporter[]? markdownExporters, Cancel ctx)
 	{
+		SetFeatureFlags(set);
 		var generator = new DocumentationGenerator(
 			set.DocumentationSet,
 			logger, HtmlWriter,
@@ -130,4 +133,14 @@ private async Task<GenerationResult> BuildAsync(AssemblerDocumentationSet set, b
 		return await generator.GenerateAll(ctx);
 	}
 
+	private void SetFeatureFlags(AssemblerDocumentationSet set)
+	{
+		// Enable primary nav by default
+		set.DocumentationSet.Configuration.Features.PrimaryNavEnabled = true;
+		foreach (var configurationFeatureFlag in set.AssembleContext.Environment.FeatureFlags)
+		{
+			_logger.LogInformation("Setting feature flag: {ConfigurationFeatureFlagKey}={ConfigurationFeatureFlagValue}", configurationFeatureFlag.Key, configurationFeatureFlag.Value);
+			set.DocumentationSet.Configuration.Features.Set(configurationFeatureFlag.Key, configurationFeatureFlag.Value);
+		}
+	}
 }

src/tooling/docs-assembler/assembler.yml

@@ -23,6 +23,8 @@ environments:
     content_source: next
     google_tag_manager:
       enabled: false
+    feature_flags:
+      VERSION_DROPDOWN: true
   dev:
     uri: http://localhost:4000
     content_source: next