优化xml序列化到IBufferWriter

Author: xljiulang

WebApiClientCore.Benchmarks/Program.cs

@@ -9,8 +9,8 @@ static void Main(string[] args)
         {
             BenchmarkRunner.Run<HttpGetBenchmark>();
             BenchmarkRunner.Run<HttpGetJsonBenchmark>();
-            BenchmarkRunner.Run<HttpPostXmlBenchmark>();
             BenchmarkRunner.Run<HttpPostJsonBenchmark>();
+            BenchmarkRunner.Run<HttpPostXmlBenchmark>();
             BenchmarkRunner.Run<HttpPutFormBenchmark>();
         }
     }

WebApiClientCore.Test/Attributes/ParameterAttributes/XmlContentAttributeTest.cs

@@ -37,9 +37,7 @@ public async Task OnRequestAsyncTest()
             await attr.OnRequestAsync(new ApiParameterContext(context, 0));
             var body = await context.HttpContext.RequestMessage.Content!.ReadAsStringAsync();
 
-            using var bufferWriter = new RecyclableBufferWriter<byte>();
-            XmlSerializer.Serialize(bufferWriter, context.Arguments[0], null);
-            var target = Encoding.GetEncoding(attr.CharSet).GetString(bufferWriter.WrittenSpan);
+            var target = XmlSerializer.Serialize(context.Arguments[0], null);
             Assert.True(body == target);
         }
     }

WebApiClientCore/ApiParameterContextExtensions.cs

@@ -89,6 +89,21 @@ public static void SerializeToJson(this ApiParameterContext context, IBufferWrit
         /// <returns></returns>
         [RequiresUnreferencedCode("Members from serialized types may be trimmed if not referenced directly")]
         public static string? SerializeToXml(this ApiParameterContext context, Encoding? encoding)
+        {
+            using var bufferWriter = new RecyclableBufferWriter<char>();
+            context.SerializeToXml(encoding, bufferWriter);
+            return bufferWriter.WrittenSpan.ToString();
+        }
+
+        /// <summary>
+        /// 序列化参数值为Xml
+        /// </summary>
+        /// <param name="context"></param>
+        /// <param name="bufferWriter">数据写入器</param>
+        /// <param name="encoding">xml的编码</param>
+        /// <returns></returns>
+        [RequiresUnreferencedCode("Members from serialized types may be trimmed if not referenced directly")]
+        public static void SerializeToXml(this ApiParameterContext context, Encoding? encoding, IBufferWriter<char> bufferWriter)
         {
             var options = context.HttpContext.HttpApiOptions.XmlSerializeOptions;
             if (encoding != null && encoding.Equals(options.Encoding) == false)
@@ -97,7 +112,7 @@ public static void SerializeToJson(this ApiParameterContext context, IBufferWrit
                 options.Encoding = encoding;
             }
 
-            return XmlSerializer.Serialize(context.ParameterValue, options);
+            XmlSerializer.Serialize(context.ParameterValue, options, bufferWriter);
         }
 
         /// <summary>

WebApiClientCore/Attributes/ParameterAttributes/XmlContentAttribute.cs

@@ -3,6 +3,7 @@
 using System.Text;
 using System.Threading.Tasks;
 using WebApiClientCore.HttpContents;
+using WebApiClientCore.Internals;
 
 namespace WebApiClientCore.Attributes
 {
@@ -34,14 +35,9 @@ public string CharSet
         [UnconditionalSuppressMessage("Trimming", "IL2026:Members annotated with 'RequiresUnreferencedCodeAttribute' require dynamic access otherwise can break functionality when trimming application code", Justification = "<Pending>")]
         protected override Task SetHttpContentAsync(ApiParameterContext context)
         {
-            var options = context.HttpContext.HttpApiOptions.XmlSerializeOptions;
-            if (encoding != null && encoding.Equals(options.Encoding) == false)
-            {
-                options = options.Clone();
-                options.Encoding = encoding;
-            }
-
-            context.HttpContext.RequestMessage.Content = new XmlContent(context.ParameterValue, options);
+            using var bufferWriter = new RecyclableBufferWriter<char>();
+            context.SerializeToXml(this.encoding, bufferWriter);
+            context.HttpContext.RequestMessage.Content = new XmlContent(bufferWriter.WrittenSpan, this.encoding);
             return Task.CompletedTask;
         }
     }

WebApiClientCore/HttpContents/XmlContent.cs

@@ -1,8 +1,6 @@
-using System.Diagnostics.CodeAnalysis;
+using System;
 using System.Net.Http.Headers;
 using System.Text;
-using System.Xml;
-using WebApiClientCore.Serialization;
 
 namespace WebApiClientCore.HttpContents
 {
@@ -23,26 +21,12 @@ public class XmlContent : BufferContent
         /// </summary>
         /// <param name="xml">xml内容</param>
         /// <param name="encoding">编码</param>
-        public XmlContent(string? xml, Encoding encoding)
+        public XmlContent(ReadOnlySpan<char> xml, Encoding encoding)
         {
             encoding.GetBytes(xml, this);
             this.Headers.ContentType = encoding == Encoding.UTF8
                 ? defaultMediaType :
                 new MediaTypeHeaderValue(MediaType) { CharSet = encoding.WebName };
         }
-
-        /// <summary>
-        /// xml内容
-        /// </summary>
-        /// <param name="obj">xml实体</param>
-        /// <param name="xmlWriterSettings">xml写入设置项</param>
-        [RequiresUnreferencedCode("Members from serialized types may be trimmed if not referenced directly")]
-        public XmlContent(object? obj, XmlWriterSettings xmlWriterSettings)
-        {
-            XmlSerializer.Serialize(this, obj, xmlWriterSettings);
-            this.Headers.ContentType = xmlWriterSettings.Encoding == Encoding.UTF8
-                ? defaultMediaType
-                : new MediaTypeHeaderValue(MediaType) { CharSet = xmlWriterSettings.Encoding.WebName };
-        }
     }
 }

WebApiClientCore/Serialization/XmlSerializer.cs

@@ -6,6 +6,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using System.Xml;
+using WebApiClientCore.Internals;
 
 namespace WebApiClientCore.Serialization
 {
@@ -31,10 +32,9 @@ public static class XmlSerializer
                 return null;
             }
 
-            var settings = options ?? writerSettings;
-            using var writer = new EncodingStringWriter(settings.Encoding);
-            SerializeCore(writer, obj, settings);
-            return writer.ToString();
+            using var bufferWriter = new RecyclableBufferWriter<char>();
+            Serialize(obj, options, bufferWriter);
+            return bufferWriter.WrittenSpan.ToString();
         }
 
         /// <summary>
@@ -44,22 +44,16 @@ public static class XmlSerializer
         /// <param name="obj">对象</param>
         /// <param name="options">配置选项</param> 
         [RequiresUnreferencedCode("Members from serialized types may be trimmed if not referenced directly")]
-        public static void Serialize(IBufferWriter<byte> bufferWriter, object? obj, XmlWriterSettings? options)
+        public static void Serialize(object? obj, XmlWriterSettings? options, IBufferWriter<char> bufferWriter)
         {
             if (obj == null)
             {
                 return;
             }
 
             var settings = options ?? writerSettings;
-            using var writer = new BufferTextWriter(bufferWriter, settings.Encoding);
-            SerializeCore(writer, obj, settings);
-        }
-
-        [RequiresUnreferencedCode("Members from serialized types may be trimmed if not referenced directly")]
-        private static void SerializeCore(TextWriter textWriter, object obj, XmlWriterSettings settings)
-        {
-            using var xmlWriter = XmlWriter.Create(textWriter, settings);
+            using var writer = new XmlBufferWriter(bufferWriter, settings.Encoding);
+            using var xmlWriter = XmlWriter.Create(writer, settings);
             var xmlSerializer = new System.Xml.Serialization.XmlSerializer(obj.GetType());
             xmlSerializer.Serialize(xmlWriter, obj);
         }
@@ -92,25 +86,26 @@ private static void SerializeCore(TextWriter textWriter, object obj, XmlWriterSe
         }
 
 
-        private class BufferTextWriter : TextWriter
+        private class XmlBufferWriter : TextWriter
         {
-            private readonly IBufferWriter<byte> bufferWriter;
+            private readonly IBufferWriter<char> bufferWriter;
 
             public override Encoding Encoding { get; }
 
-            public BufferTextWriter(IBufferWriter<byte> bufferWriter, Encoding encoding)
+            public XmlBufferWriter(IBufferWriter<char> bufferWriter, Encoding encoding)
             {
                 this.bufferWriter = bufferWriter;
                 this.Encoding = encoding;
             }
+
             public override Task FlushAsync()
             {
                 return Task.CompletedTask;
             }
 
             public override void Write(ReadOnlySpan<char> buffer)
             {
-                this.Encoding.GetBytes(buffer, this.bufferWriter);
+                this.bufferWriter.Write(buffer);
             }
 
             public override void Write(char value)
@@ -187,26 +182,5 @@ public override Task WriteLineAsync(ReadOnlyMemory<char> buffer, CancellationTok
                 return Task.CompletedTask;
             }
         }
-
-
-        /// <summary>
-        /// 表示可指定编码文本写入器
-        /// </summary>
-        private class EncodingStringWriter : StringWriter
-        {
-            /// <summary>
-            /// 获取编码
-            /// </summary>
-            public override Encoding Encoding { get; }
-
-            /// <summary>
-            /// 可指定编码文本写入器
-            /// </summary>
-            /// <param name="encoding">编码</param>
-            public EncodingStringWriter(Encoding encoding)
-            {
-                this.Encoding = encoding;
-            }
-        }
     }
 }