Web API性能优化（一）压缩

简单的应用场景：分页获取日志JSON信息。

很简单的实现，简单的记录一下

未压缩时候

使用PostMan请求http://localhost:34390/api/gpm/syslog/page?pageindex=1&pagesize=10

上图用到了一些技术：AOP、IOC、Request/Response模式（个人觉得十分适合WebAPI），这里不介绍。ApiResullt是我封装的一个类（自动序列化），至于为什么自己造一个，只是本人觉得舒服！这个最重要。

响应结果：可以看到Size:2.04KB，Content-Length:1607

使用压缩

使用DotNetZip压缩，当然使用AOP方式，使用默认压缩级别

 /// <summary>
 /// 压缩返回信息
 /// </summary>
 [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, Inherited = true, AllowMultiple = true)]
 public class CompressionAttribute : ActionFilterAttribute
 {
     public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
     {
         var content = actionExecutedContext.Response.Content;
         var acceptEncoding = actionExecutedContext.Request.Headers.AcceptEncoding.
             Where(x => x.Value == "gzip" || x.Value == "deflate").ToList();
         if (acceptEncoding.HasItems() && content != null && actionExecutedContext.Request.Method != HttpMethod.Options)
         {
             var first = acceptEncoding.FirstOrDefault();
             if (first != null)
             {
                 var bytes = content.ReadAsByteArrayAsync().Result;
                 switch (first.Value)
                 {
                     case "gzip":
                         actionExecutedContext.Response.Content = new ByteArrayContent(CompressionHelper.GZipBytes(bytes));
                         actionExecutedContext.Response.Content.Headers.Add("Content-Encoding", "gzip");
                         break;
                     case "deflate":
                         actionExecutedContext.Response.Content = new ByteArrayContent(CompressionHelper.DeflateBytes(bytes));
                         actionExecutedContext.Response.Content.Headers.Add("Content-encoding", "deflate");
                         break;
                 }
             }
         }
         base.OnActionExecuted(actionExecutedContext);
     }
 }
 /// <summary>
 /// 压缩帮助类
 /// </summary>
 internal static class CompressionHelper
 {
     public static byte[] DeflateBytes(byte[] bytes)
     {
         if (!bytes.HasItems())
         {
             return null;
         }
         using (var output = new MemoryStream())
         {
             using (var compressor = new Ionic.Zlib.DeflateStream(output, Ionic.Zlib.CompressionMode.Compress, Ionic.Zlib.CompressionLevel.Default))
             {
                 compressor.Write(bytes, , bytes.Length);
             }
             return output.ToArray();
         }
     }

     public static byte[] GZipBytes(byte[] bytes)
     {
         if (!bytes.HasItems())
         {
             return null;
         }
         using (var output = new MemoryStream())
         {
             using (var compressor = new Ionic.Zlib.GZipStream(output, Ionic.Zlib.CompressionMode.Compress, Ionic.Zlib.CompressionLevel.Default))
             {
                 compressor.Write(bytes, , bytes.Length);
             }
             return output.ToArray();
         }
     }
 }

请求响应结果：Size:833B，Content-Length:329，提升效果十分明显，细心的朋友会发现响应时间变长了，当然这是由于压缩需要时间造成的，但是影响不大