Remove [CONTENT] markers and replace with better inline rendering method (#1337)

Author: Mpdreamz

Directory.Packages.props

@@ -40,7 +40,7 @@
     <PackageVersion Include="Markdig" Version="0.41.1" />
     <PackageVersion Include="NetEscapades.EnumGenerators" Version="1.0.0-beta12" PrivateAssets="all" ExcludeAssets="runtime" />
     <PackageVersion Include="Proc" Version="0.9.1" />
-    <PackageVersion Include="RazorSlices" Version="0.8.1" />
+    <PackageVersion Include="RazorSlices" Version="0.9.1" />
     <PackageVersion Include="Samboy063.Tomlet" Version="6.0.0" />
     <PackageVersion Include="Slugify.Core" Version="4.0.1" />
     <PackageVersion Include="SoftCircuits.IniFileParser" Version="2.7.0" />

src/Elastic.Markdown/Helpers/DocumentationObjectPoolProvider.cs

@@ -0,0 +1,73 @@
+// 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.Text;
+using Elastic.Markdown.Myst;
+using Markdig.Renderers;
+using Microsoft.Extensions.ObjectPool;
+
+namespace Elastic.Markdown.Helpers;
+
+internal static class DocumentationObjectPoolProvider
+{
+	private static readonly ObjectPoolProvider PoolProvider = new DefaultObjectPoolProvider();
+
+	public static readonly ObjectPool<StringBuilder> StringBuilderPool = PoolProvider.CreateStringBuilderPool(256, 4 * 1024);
+	public static readonly ObjectPool<ReusableStringWriter> StringWriterPool = PoolProvider.Create(new ReusableStringWriterPooledObjectPolicy());
+	public static readonly ObjectPool<HtmlRenderSubscription> HtmlRendererPool = PoolProvider.Create(new HtmlRendererPooledObjectPolicy());
+
+
+	private sealed class ReusableStringWriterPooledObjectPolicy : IPooledObjectPolicy<ReusableStringWriter>
+	{
+		public ReusableStringWriter Create() => new();
+
+		public bool Return(ReusableStringWriter obj)
+		{
+			obj.Reset();
+			return true;
+		}
+	}
+
+	public sealed class HtmlRenderSubscription
+	{
+		public required HtmlRenderer HtmlRenderer { get; init; }
+		public StringBuilder? RentedStringBuilder { get; internal set; }
+	}
+
+	private sealed class HtmlRendererPooledObjectPolicy : IPooledObjectPolicy<HtmlRenderSubscription>
+	{
+		public HtmlRenderSubscription Create()
+		{
+			var stringBuilder = StringBuilderPool.Get();
+			using var stringWriter = StringWriterPool.Get();
+			stringWriter.SetStringBuilder(stringBuilder);
+			var renderer = new HtmlRenderer(stringWriter);
+			MarkdownParser.Pipeline.Setup(renderer);
+
+			return new HtmlRenderSubscription { HtmlRenderer = renderer, RentedStringBuilder = stringBuilder };
+		}
+
+		public bool Return(HtmlRenderSubscription subscription)
+		{
+			//subscription.RentedStringBuilder = null;
+			//return string builder
+			if (subscription.RentedStringBuilder is not null)
+				StringBuilderPool.Return(subscription.RentedStringBuilder);
+
+			subscription.RentedStringBuilder = null;
+
+			var renderer = subscription.HtmlRenderer;
+
+			//reset string writer
+			((ReusableStringWriter)renderer.Writer).Reset();
+
+			// reseed string writer with string builder
+			var stringBuilder = StringBuilderPool.Get();
+			subscription.RentedStringBuilder = stringBuilder;
+			((ReusableStringWriter)renderer.Writer).SetStringBuilder(stringBuilder);
+			return true;
+		}
+	}
+
+}

src/Elastic.Markdown/Helpers/ReusableStringWriter.cs

@@ -0,0 +1,135 @@
+// 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.Text;
+
+namespace Elastic.Markdown.Helpers;
+
+internal sealed class ReusableStringWriter : TextWriter
+{
+	private static UnicodeEncoding? CurrentEncoding;
+
+	private StringBuilder? _sb;
+
+	public override Encoding Encoding => CurrentEncoding ??= new UnicodeEncoding(false, false);
+
+	public void SetStringBuilder(StringBuilder sb) => _sb = sb;
+
+	public void Reset() => _sb = null;
+
+	public override void Write(char value) => _sb?.Append(value);
+
+	public override void Write(char[] buffer, int index, int count)
+	{
+		ArgumentNullException.ThrowIfNull(buffer);
+		ArgumentOutOfRangeException.ThrowIfNegative(index);
+		ArgumentOutOfRangeException.ThrowIfNegative(count);
+
+		if (buffer.Length - index < count)
+			throw new ArgumentException("Out of range");
+
+		_ = _sb?.Append(buffer, index, count);
+	}
+
+	public override void Write(ReadOnlySpan<char> buffer) => _sb?.Append(buffer);
+
+	public override void Write(string? value)
+	{
+		if (value is not null)
+			_ = _sb?.Append(value);
+	}
+
+	public override void Write(StringBuilder? value) => _sb?.Append(value);
+
+	public override void WriteLine(ReadOnlySpan<char> buffer)
+	{
+		_ = _sb?.Append(buffer);
+		WriteLine();
+	}
+
+	public override void WriteLine(StringBuilder? value)
+	{
+		_ = _sb?.Append(value);
+		WriteLine();
+	}
+
+	#region Task based Async APIs
+
+	public override Task WriteAsync(char value)
+	{
+		Write(value);
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteAsync(string? value)
+	{
+		Write(value);
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteAsync(char[] buffer, int index, int count)
+	{
+		Write(buffer, index, count);
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteAsync(ReadOnlyMemory<char> buffer, CancellationToken cancellationToken = default)
+	{
+		if (cancellationToken.IsCancellationRequested)
+			return Task.FromCanceled(cancellationToken);
+
+		Write(buffer.Span);
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteAsync(StringBuilder? value, CancellationToken cancellationToken = default)
+	{
+		if (cancellationToken.IsCancellationRequested)
+			return Task.FromCanceled(cancellationToken);
+
+		_ = _sb?.Append(value);
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteLineAsync(char value)
+	{
+		WriteLine(value);
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteLineAsync(string? value)
+	{
+		WriteLine(value);
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteLineAsync(StringBuilder? value, CancellationToken cancellationToken = default)
+	{
+		if (cancellationToken.IsCancellationRequested)
+			return Task.FromCanceled(cancellationToken);
+
+		_ = _sb?.Append(value);
+		WriteLine();
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteLineAsync(char[] buffer, int index, int count)
+	{
+		WriteLine(buffer, index, count);
+		return Task.CompletedTask;
+	}
+
+	public override Task WriteLineAsync(ReadOnlyMemory<char> buffer, CancellationToken cancellationToken = default)
+	{
+		if (cancellationToken.IsCancellationRequested)
+			return Task.FromCanceled(cancellationToken);
+
+		WriteLine(buffer.Span);
+		return Task.CompletedTask;
+	}
+
+	public override Task FlushAsync() => Task.CompletedTask;
+
+	#endregion
+}

src/Elastic.Markdown/IO/MarkdownFile.cs

@@ -357,7 +357,7 @@ private YamlFrontMatter ReadYamlFrontMatter(string raw)
 		}
 	}
 
-	public string CreateHtml(MarkdownDocument document)
+	public static string CreateHtml(MarkdownDocument document)
 	{
 		//we manually render title and optionally append an applies block embedded in yaml front matter.
 		var h1 = document.Descendants<HeadingBlock>().FirstOrDefault(h => h.Level == 1);

src/Elastic.Markdown/Myst/CodeBlocks/EnhancedCodeBlockHtmlRenderer.cs

@@ -20,20 +20,14 @@ public class EnhancedCodeBlockHtmlRenderer : HtmlObjectRenderer<EnhancedCodeBloc
 	private const int TabWidth = 4;
 
 	[SuppressMessage("Reliability", "CA2012:Use ValueTasks correctly")]
-	private static void RenderRazorSlice<T>(RazorSlice<T> slice, HtmlRenderer renderer, EnhancedCodeBlock block)
-	{
-		var html = slice.RenderAsync().GetAwaiter().GetResult();
-		var blocks = html.Split("[CONTENT]", 2, StringSplitOptions.RemoveEmptyEntries);
-		_ = renderer.Write(blocks[0]);
-		RenderCodeBlockLines(renderer, block);
-		_ = renderer.Write(blocks[1]);
-	}
+	private static void RenderRazorSlice<T>(RazorSlice<T> slice, HtmlRenderer renderer) =>
+		slice.RenderAsync(renderer.Writer).GetAwaiter().GetResult();
 
 	/// <summary>
 	/// Renders the code block lines while also removing the common indentation level.
 	/// Required because EnableTrackTrivia preserves extra indentation.
 	/// </summary>
-	private static void RenderCodeBlockLines(HtmlRenderer renderer, EnhancedCodeBlock block)
+	public static void RenderCodeBlockLines(HtmlRenderer renderer, EnhancedCodeBlock block)
 	{
 		var commonIndent = GetCommonIndent(block);
 		var hasCode = false;
@@ -134,10 +128,11 @@ protected override void Write(HtmlRenderer renderer, EnhancedCodeBlock block)
 			CrossReferenceName = string.Empty,// block.CrossReferenceName,
 			Language = block.Language,
 			Caption = block.Caption,
-			ApiCallHeader = block.ApiCallHeader
+			ApiCallHeader = block.ApiCallHeader,
+			EnhancedCodeBlock = block
 		});
 
-		RenderRazorSlice(slice, renderer, block);
+		RenderRazorSlice(slice, renderer);
 		if (!block.InlineAnnotations && callOuts.Count > 0)
 		{
 			var index = block.Parent!.IndexOf(block);
@@ -240,7 +235,6 @@ private static void RenderAppliesToHtml(HtmlRenderer renderer, AppliesToDirectiv
 		var slice = ApplicableToDirective.Create(appliesTo);
 		if (appliesTo is null || appliesTo == FrontMatter.ApplicableTo.All)
 			return;
-		var html = slice.RenderAsync().GetAwaiter().GetResult();
-		_ = renderer.Write(html);
+		slice.RenderAsync(renderer.Writer).GetAwaiter().GetResult();
 	}
 }