实现的功能

• 简单的路由系统
• 支持中间件
• 简单Filter支持
• 只支持HttpPost、HttpGet
• 使用Dotliquid做为视图渲染引擎

核心实现

• HttpChannel

  • 复制监听Tcp请求，并按照Http协议将tcp数据传输解析为HttpRequest数据实例，解析完调用HttpHandler继续下一步处理

• HttpRequest

  • 单次Http请求信息，包含 HttpMethod、Version、Url、HttpHeader、Cookies等信息

• HttpResponse

  • Http响应信息

• DefaultHttpHandler

  • 实现IHttpHandler，负责Middleware责任链的创建、执行

  •   private IMiddleware BuildMiddlewareChain()
      {
          var builder = new MiddlewareChainBuilder();
          builder.Use(new StaticFileMiddleware());
          builder.Use(new MvcMiddleware(route));
          return builder.Build();
      }
    
    
      public async Task<HttpResponse> ProcessAsync(HttpRequest httpRequest)
      {
          var chain = BuildMiddlewareChain();
          return await chain.Invoke(httpRequest);
      }

• MvcMiddleware

  • 内置的中间件，mvc功能具体实现[FIlter模式实现]

  • public override async Task<HttpResponse> Invoke(HttpRequest httpRequest)
    {
        try
        {
            var context = new ActionExecuteContext
            {
                HttpRequest = httpRequest
            };
    
            var (controller, methodInfo, parameter) = route.Route(httpRequest);
            if (controller == null)
            {
                return await HttpResponseHelper.CreateNotFoundResponseAsync();
            }
    
            context.Controller = controller;
            context.Action = methodInfo;
            ((ControllerBase)controller).Request = httpRequest;
    
            var filterList = GetFilters(controller, methodInfo);
            var stack = new Stack<IFilter>();
            for (var i = 0; i < filterList.Count; i++)
            {
                var filter = filterList[i];
                await filter.OnActionExecutingAsync(context);
                if (context.Final)
                {
                    return context.HttpResponse;
                }
                stack.Push(filter);
            }
    
            await controller.OnActionExecutingAsync(context);
    
            if (context.Final)
            {
                return context.HttpResponse;
            }
    
            var parameters = new List<object>();
            if (parameter != null)
            {
                parameters.Add(parameter);
            }
    
            if (methodInfo.ReturnType.IsGenericType) //Task<IActionResult>
            {
                var actionResult = await (methodInfo.Invoke(controller, parameters.ToArray()) as Task<IActionResult>);
                context.HttpResponse = await actionResult.ExecuteResultAsync();
            }
            else
            {
                var actionResult = methodInfo.Invoke(controller, parameters.ToArray()) as IActionResult;
                context.HttpResponse = await actionResult.ExecuteResultAsync();
            }
    
            context.HttpResponse.Cookies.AddRange(controller.ResponseCookie);
    
            await controller.OnActionExecutedAsync(context);
    
            if (context.Final)
            {
                return context.HttpResponse;
            }
    
            while (stack.Count != 0)
            {
                var filter = stack.Pop();
                await filter.OnActionExecutedAsync(context);
    
                if (context.Final)
                {
                    return context.HttpResponse;
                }
            }
            return context.HttpResponse;
        }
        catch (Exception e)
        {
            return await HttpResponseHelper.CreateDefaultErrorResponseAsync(e);
        }
    }

• EasyRoute

  • 实现最简单的路由解析【URL—> IController/Method】

  • Controller实例化使用netcore自带的IOC框架实现

  • public (IController, MethodInfo, object) Route(HttpRequest request)
    {
        var path = request.AbsolutePath;
        Type controllerType;
        MethodInfo methodInfo;
        switch (request.HttpMethod)
        {
            case HttpMethod.Get:
                if (httpGetRoutes.ContainsKey(path))
                {
                    (controllerType, methodInfo) = httpGetRoutes[path];
                }
                else
                {
                    return (null, null, null);
                }
                break;
            case HttpMethod.Post:
                if (httpPostRoutes.ContainsKey(path))
                {
                    (controllerType, methodInfo) = httpPostRoutes[path];
                }
                else
                {
                    return (null, null, null);
                }
                break;
            default://Unsupport httpmethod
                return (null, null, null);
        }
        var controllerObj = ServiceLocator.Instance.GetService(controllerType) as IController;
        //var controllerObj = Activator.CreateInstance(controllerType) as IController;
        object parameter = null;
        var parameterType = methodInfo.GetParameters().SingleOrDefault()?.ParameterType;
        if (parameterType != null)
        {
            parameter = ResolveParameter(parameterType, request);
        }
    
        return (controllerObj, methodInfo, parameter);
    }

• IActionResult

  • 执行结果的抽象，类比MVC的IActionResult

  • 内置类型

    • HttpStatusCodeResult：只返回特定StatusCode，没有具体内容

    • JsonResult：返回JSON结果，content-type：application/json

    • RedirectResult：返回302

    • ViewResult：使用DotLiquid作为视图渲染引擎

      public async Task<HttpResponse> ExecuteResultAsync()
      {
          var absoluteName = $"Views/{ViewName}";
          Template template;
          if (viewCache.ContainsKey(absoluteName))
          {
              template = viewCache[absoluteName];
          }
          else
          {
              var templateStr = Template.FileSystem.ReadTemplateFile(new Context(CultureInfo.CurrentCulture), absoluteName);
              template = Template.Parse(templateStr);
              viewCache.Add(absoluteName, template);
          }
          var content = template.Render(Hash.FromAnonymousObject(ViewData));
      
          var res = new HttpResponse();
      
          await res.WriteBodyAsync(Constants.DefaultEncoding.GetBytes(content));
      
          return res;
      }

• IController

  • mvc控制器接口

• HttpCookie

  • cookie操作类

• IFilter

  • 过滤器接口

     public interface IFilter
     {
         int Order { get; set; }
         Task OnActionExecutingAsync(ActionExecuteContext context);
         Task OnActionExecutedAsync(ActionExecuteContext context);
     }

其他

• 本项目只为学习使用，如有错误，请指出
• 本项目为另一个项目 EasyProxy 的附属产物，所以没有独立的github仓库，具体目录为 HttpServer