从专题三开始分析Community Server的一些具体的技术实现,根据IIS对请求的处理流程,从HttpModule& HttpHandler切入话题,同时你也可以通过一系列的专题了解CS的运行过程,不只如此,所有的.Net 1.1 构架的Web App都是以同样的顺序执行的。
先了解一下IIS系统。它是一个程序,负责对网站的内容进行管理并且处理对客户的请求做出反应。当用户对一个页面提出请求时,IIS做如下反应(不考虑权限问题):
1.把对方请求的虚拟路径转换成物理路径
2.根据物理路径搜索请求的文件
3.找到文件后,获取文件的内容
4.生成Http头信息。
5.向客户端发送所有的文件内容:首先是头信息,然后是Html内容,最后是其它文件的内容。
6.客户端IE浏览器获得信息后,解析文件内容,找出其中的引用文件,如.js .css .gif等,向IIS请求这些文件。
7.IIS获取请求后,发送文件内容。
8.当浏览器获取所有内容后,生成内容界面,客户就看到图像/文本/其它内容了。
但是IIS本身是不支持动态页面的,也就是说它仅仅支持静态html页面的内容,对于如.asp,.aspx,.cgi,.php等,IIS并不会处理这些标记,它就会把它当作文本,丝毫不做处理发送到客户端。为了解决这个问题。IIS有一种机制,叫做ISAPI的筛选器,这个东西是一个标准组件(COM组件),当在在访问IIS所不能处理的文件时,如asp.net 1.1 中的IIS附加ISAPI筛选器如图:
![](https://images.cnblogs.com/cnblogs_com/ugoer/%7BAAAECACD-7D5F-45F5-A112-6CE0A146536F%7D0.jpg)
Asp.net服务在注册到IIS的时候,会把每个扩展可以处理的文件扩展名注册到IIS里面(如:*.ascx、*.aspx等)。扩展启动后,就根据定义好的方式来处理IIS所不能处理的文件,然后把控制权跳转到专门处理代码的进程中。让这个进程开始处理代码,生成标准的HTML代码,生成后把这些代码加入到原有的Html中,最后把完整的Html返回给IIS,IIS再把内容发送到客户端。
有上面对ISAPI的简单描述,我们把HttpModule& HttpHandler分开讨论,并且结合CS进行具体的实现分析。
HttpModule:
HttpModule实现了ISAPI Filter的功能,是通过对IhttpModule接口的继承来处理。下面打开CS中的CommunityServerComponents项目下的CSHttpModule.cs文件(放在HttpModule目录)
//------------------------------------------------------------------------------
// <copyright company="Telligent Systems">
// Copyright (c) Telligent Systems Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
using System;
using System.IO;
using System.Web;
using CommunityServer.Components;
using CommunityServer.Configuration;
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namespace CommunityServer
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{
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// *********************************************************************
// CSHttpModule
//
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/// <summary>
/// This HttpModule encapsulates all the forums related events that occur
/// during ASP.NET application start-up, errors, and end request.
/// </summary>
// ***********************************************************************/
public class CSHttpModule : IHttpModule
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{
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#region Member variables and inherited properties / methods
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public String ModuleName
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{
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get { return "CSHttpModule"; }
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// *********************************************************************
// ForumsHttpModule
//
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
/// <summary>
/// Initializes the HttpModule and performs the wireup of all application
/// events.
/// </summary>
/// <param name="application">Application the module is being run for</param>
public void Init(HttpApplication application)
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{
// Wire-up application events
//
application.BeginRequest += new EventHandler(this.Application_BeginRequest);
application.AuthenticateRequest += new EventHandler(Application_AuthenticateRequest);
application.Error += new EventHandler(this.Application_OnError);
application.AuthorizeRequest += new EventHandler(this.Application_AuthorizeRequest);
//settingsID = SiteSettingsManager.GetSiteSettings(application.Context).SettingsID;
Jobs.Instance().Start();
//CSException ex = new CSException(CSExceptionType.ApplicationStart, "Appication Started " + AppDomain.CurrentDomain.FriendlyName);
//ex.Log();
}
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//int settingsID;
public void Dispose()
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{
//CSException ex = new CSException(CSExceptionType.ApplicationStop, "Application Stopping " + AppDomain.CurrentDomain.FriendlyName);
//ex.Log(settingsID);
Jobs.Instance().Stop();
}
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![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
#region Installer
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#endregion
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#endregion
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#region Application OnError
private void Application_OnError (Object source, EventArgs e)
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{
HttpApplication application = (HttpApplication)source;
HttpContext context = application.Context;
CSException csException = context.Server.GetLastError() as CSException;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
if(csException == null)
csException = context.Server.GetLastError().GetBaseException() as CSException;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
try
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{
if (csException != null)
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{
switch (csException.ExceptionType)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
case CSExceptionType.UserInvalidCredentials:
case CSExceptionType.AccessDenied:
case CSExceptionType.AdministrationAccessDenied:
case CSExceptionType.ModerateAccessDenied:
case CSExceptionType.PostDeleteAccessDenied:
case CSExceptionType.PostProblem:
case CSExceptionType.UserAccountBanned:
case CSExceptionType.ResourceNotFound:
case CSExceptionType.UserUnknownLoginError:
case CSExceptionType.SectionNotFound:
csException.Log();
break;
}
}
else
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
Exception ex = context.Server.GetLastError();
if(ex.InnerException != null)
ex = ex.InnerException;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
csException = new CSException(CSExceptionType.UnknownError, ex.Message, context.Server.GetLastError());
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
System.Data.SqlClient.SqlException sqlEx = ex as System.Data.SqlClient.SqlException;
if(sqlEx == null || sqlEx.Number != -2) //don't log time outs
csException.Log();
}
}
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
catch{} //not much to do here, but we want to prevent infinite looping with our error handles
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSEvents.CSException(csException);
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
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#endregion
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
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#region Application AuthenticateRequest
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private void Application_AuthenticateRequest(Object source, EventArgs e)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
HttpContext context = HttpContext.Current;
Provider p = null;
ExtensionModule module = null;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// If the installer is making the request terminate early
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
if (CSConfiguration.GetConfig().AppLocation.CurrentApplicationType == ApplicationType.Installer) {
return;
}
// Only continue if we have a valid context
//
if ((context == null) || (context.User == null))
return;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
try
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{
// Logic to handle various authentication types
//
switch(context.User.Identity.GetType().Name.ToLower())
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Microsoft passport
case "passportidentity":
p = (Provider) CSConfiguration.GetConfig().Extensions["PassportAuthentication"];
module = ExtensionModule.Instance(p);
if(module != null)
module.ProcessRequest();
else
goto default;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Windows
case "windowsidentity":
p = (Provider) CSConfiguration.GetConfig().Extensions["WindowsAuthentication"];
module = ExtensionModule.Instance(p);
if(module != null)
module.ProcessRequest();
else
goto default;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Forms
case "formsidentity":
p = (Provider) CSConfiguration.GetConfig().Extensions["FormsAuthentication"];
module = ExtensionModule.Instance(p);
if(module != null)
module.ProcessRequest();
else
goto default;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Custom
case "customidentity":
p = (Provider) CSConfiguration.GetConfig().Extensions["CustomAuthentication"];
module = ExtensionModule.Instance(p);
if(module != null)
module.ProcessRequest();
else
goto default;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
default:
CSContext.Current.UserName = context.User.Identity.Name;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
}
catch( Exception ex )
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
CSException forumEx = new CSException( CSExceptionType.UnknownError, "Error in AuthenticateRequest", ex );
forumEx.Log();
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throw forumEx;
}
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// // Get the roles the user belongs to
// //
// Roles roles = new Roles();
// roles.GetUserRoles();
}
#endregion
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
#region Application AuthorizeRequest
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
private void Application_AuthorizeRequest (Object source, EventArgs e) {
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
if (CSConfiguration.GetConfig().AppLocation.CurrentApplicationType == ApplicationType.Installer)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
//CSContext.Create(context);
return;
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
HttpApplication application = (HttpApplication)source;
HttpContext context = application.Context;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSContext csContext = CSContext.Current;
//bool enableBannedUsersToLogin = CSContext.Current.SiteSettings.EnableBannedUsersToLogin;
// // If the installer is making the request terminate early
// if (csContext.ApplicationType == ApplicationType.Installer) {
// return;
// }
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
//csContext.User = CSContext.Current.User;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSEvents.UserKnown(csContext.User);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
ValidateApplicationStatus(csContext);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Track anonymous users
//
Users.TrackAnonymousUsers(context);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Do we need to force the user to login?
//
if (context.Request.IsAuthenticated)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
string username = context.User.Identity.Name;
if (username != null)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
string[] roles = CommunityServer.Components.Roles.GetUserRoleNames(username);
if (roles != null && roles.Length > 0)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
csContext.RolesCacheKey = string.Join(",",roles);
}
}
}
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
#endregion
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
#region Application BeginRequest
private void Application_BeginRequest(Object source, EventArgs e)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
HttpApplication application = (HttpApplication)source;
HttpContext context = application.Context;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSConfiguration config = CSConfiguration.GetConfig();
// If the installer is making the request terminate early
if (config.AppLocation.CurrentApplicationType == ApplicationType.Installer)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
//CSContext.Create(context);
return;
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CheckWWWStatus(config,context);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSContext.Create(context, ReWriteUrl(context));
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
private void CheckWWWStatus(CSConfiguration config, HttpContext context)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
if(config.WWWStatus == WWWStatus.Ignore)
return;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
const string withWWW = "http://www.";
const string noWWW = "http://";
string rawUrl = context.Request.Url.ToString().ToLower();
bool isWWW = rawUrl.StartsWith(withWWW);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
if(config.WWWStatus == WWWStatus.Remove && isWWW)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
context.Response.Redirect(rawUrl.Replace(withWWW, noWWW));
}
else if(config.WWWStatus == WWWStatus.Require && !isWWW)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
context.Response.Redirect(rawUrl.Replace(noWWW, withWWW));
}
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
#region ReWriteUrl
private bool ReWriteUrl(HttpContext context)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// we're now allowing each individual application to be turned on and off individually. So before we allow
// a request to go through we need to check if this product is disabled and the path is for the disabled product,
// if so we display the disabled product page.
//
// I'm also allowing the page request to go through if the page request is for an admin page. In the past if you
// disabled the forums you were locked out, now with this check, even if you're not on the same machine but you're accessing
// an admin path the request will be allowed to proceed, where the rest of the checks will ensure that the user has the
// permission to access the specific url.
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Url Rewriting
//
//RewriteUrl(context);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
string newPath = null;
string path = context.Request.Path;
bool isReWritten = SiteUrls.RewriteUrl(path,context.Request.Url.Query,out newPath);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
//very wachky. The first call into ReWritePath always fails with a 404.
//calling ReWritePath twice actually fixes the probelm as well. Instead,
//we use the second ReWritePath overload and it seems to work 100%
//of the time.
if(isReWritten && newPath != null)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
string qs = null;
int index = newPath.IndexOf('?');
if (index >= 0)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
qs = (index < (newPath.Length - 1)) ? newPath.Substring(index + 1) : string.Empty;
newPath = newPath.Substring(0, index);
}
context.RewritePath(newPath,null,qs);
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
return isReWritten;
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
#endregion
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
private void ValidateApplicationStatus(CSContext cntx)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
if(!cntx.User.IsAdministrator)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
string disablePath = null;
switch(cntx.Config.AppLocation.CurrentApplicationType)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
case ApplicationType.Forum:
if(cntx.SiteSettings.ForumsDisabled)
disablePath = "ForumsDisabled.htm";
break;
case ApplicationType.Weblog:
if(cntx.SiteSettings.BlogsDisabled)
disablePath = "BlogsDisabled.htm";
break;
case ApplicationType.Gallery:
if(cntx.SiteSettings.GalleriesDisabled)
disablePath = "GalleriesDisabled.htm";
break;
case ApplicationType.GuestBook:
if(cntx.SiteSettings.GuestBookDisabled)
disablePath = "GuestBookDisabled.htm";
break;
case ApplicationType.Document: //新增 ugoer
if(cntx.SiteSettings.DocumentDisabled)
disablePath = "DocumentsDisabled.htm";
break;
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
if(disablePath != null)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
string errorpath = cntx.Context.Server.MapPath(string.Format("~/Languages/{0}/errors/{1}",cntx.Config.DefaultLanguage,disablePath));
using(StreamReader reader = new StreamReader(errorpath))
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
string html = reader.ReadToEnd();
reader.Close();
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
cntx.Context.Response.Write(html);
cntx.Context.Response.End();
}
}
}
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
#endregion
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
}
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
在Web.Config中的配置:
<httpModules>
<add name="CommunityServer" type="CommunityServer.CSHttpModule, CommunityServer.Components" />
<add name="Profile" type="Microsoft.ScalableHosting.Profile.ProfileModule, MemberRole, Version=1.0.0.0, Culture=neutral, PublicKeyToken=b7c773fb104e7562"/>
<add name="RoleManager" type="Microsoft.ScalableHosting.Security.RoleManagerModule, MemberRole, Version=1.0.0.0, Culture=neutral, PublicKeyToken=b7c773fb104e7562" />
</httpModules>
CSHttpModule.cs UML:
![](https://images.cnblogs.com/cnblogs_com/ugoer/%7BFFF10B79-587B-499D-8BD9-F839EB6CB0E6%7D0.jpg)
要实现HttpModule功能需要如下步骤:
1.编写一个类,实现IhttpModule接口
2.实现Init 方法,并且注册需要的方法
3.实现注册的方法
4.实现Dispose方法,如果需要手工为类做一些清除工作,可以添加Dispose方法的实现,但这不是必需的,通常可以不为Dispose方法添加任何代码。
5.在Web.config文件中,注册您编写的类
到这里我们还需要了解一个Asp.Net的运行过程:
![](https://images.cnblogs.com/cnblogs_com/ugoer/%7B843584EE-EDF7-474A-B00A-3DE112869F45%7D0.jpg)
在图中第二步可以看到当请求开始的时候,马上就进入了HttpModule,在CS中由于实现了HttpModule的扩展CSHttpModule.cs类,因此当一个web请求发出的时候(如:一个用户访问他的blog),CS系统首先调用CSHttpModule.cs类,并且进入
public void Init(HttpApplication application)
该方法进行初始化事件:
application.BeginRequest += new EventHandler(this.Application_BeginRequest);
application.AuthenticateRequest += new EventHandler(Application_AuthenticateRequest);
application.Error += new EventHandler(this.Application_OnError);
application.AuthorizeRequest += new EventHandler(this.Application_AuthorizeRequest);
有事件就要有对应的处理方法:
private void Application_BeginRequest(Object source, EventArgs e)
private void Application_AuthenticateRequest(Object source, EventArgs e)
private void Application_OnError (Object source, EventArgs e)
private void Application_AuthorizeRequest (Object source, EventArgs e)
事件被初始化后就等待系统的触发,请求进入下一步此时系统触发Application_BeginRequest事件,事件处理内容如下:
private void Application_BeginRequest(Object source, EventArgs e)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
{
HttpApplication application = (HttpApplication)source;
HttpContext context = application.Context;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSConfiguration config = CSConfiguration.GetConfig();
// If the installer is making the request terminate early
if (config.AppLocation.CurrentApplicationType == ApplicationType.Installer)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
//CSContext.Create(context);
return;
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CheckWWWStatus(config,context);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSContext.Create(context, ReWriteUrl(context));
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
}
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
private void CheckWWWStatus(CSConfiguration config, HttpContext context)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
{
if(config.WWWStatus == WWWStatus.Ignore)
return;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
const string withWWW = "http://www.";
const string noWWW = "http://";
string rawUrl = context.Request.Url.ToString().ToLower();
bool isWWW = rawUrl.StartsWith(withWWW);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
if(config.WWWStatus == WWWStatus.Remove && isWWW)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
context.Response.Redirect(rawUrl.Replace(withWWW, noWWW));
}
else if(config.WWWStatus == WWWStatus.Require && !isWWW)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
context.Response.Redirect(rawUrl.Replace(noWWW, withWWW));
}
}
![](https://www.cnblogs.com/Images/OutliningIndicators/None.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
#region ReWriteUrl
private bool ReWriteUrl(HttpContext context)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// we're now allowing each individual application to be turned on and off individually. So before we allow
// a request to go through we need to check if this product is disabled and the path is for the disabled product,
// if so we display the disabled product page.
//
// I'm also allowing the page request to go through if the page request is for an admin page. In the past if you
// disabled the forums you were locked out, now with this check, even if you're not on the same machine but you're accessing
// an admin path the request will be allowed to proceed, where the rest of the checks will ensure that the user has the
// permission to access the specific url.
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Url Rewriting
//
//RewriteUrl(context);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
string newPath = null;
string path = context.Request.Path;
bool isReWritten = SiteUrls.RewriteUrl(path,context.Request.Url.Query,out newPath);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
//very wachky. The first call into ReWritePath always fails with a 404.
//calling ReWritePath twice actually fixes the probelm as well. Instead,
//we use the second ReWritePath overload and it seems to work 100%
//of the time.
if(isReWritten && newPath != null)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
string qs = null;
int index = newPath.IndexOf('?');
if (index >= 0)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
qs = (index < (newPath.Length - 1)) ? newPath.Substring(index + 1) : string.Empty;
newPath = newPath.Substring(0, index);
}
context.RewritePath(newPath,null,qs);
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
return isReWritten;
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
#endregion 这个事件主要做两个事情
a:为发出请求的用户初始化一个Context,初始化Context用到了线程中本地数据槽(LocalDataStoreSlot),把当前用户请求的上下文(contextb)保存在为此请求开辟的内存中。
b:判断是否需要重写 URL(检查是否需要重写的过程是对SiteUrls.config文件中正则表达式和对应Url处理的过程),如果需要重写URL,就执行asp.net级别上的RewritePath方法获得新的路径,新的路径才是真正的请求信息所在的路径。这个专题不是讲URL Rewrite,所以只要明白URL在这里就进行Rewrite就可以了,具体的后面专题会叙述。
处理完Application_BeginRequest 后进程继向下执行,随后触发了Application_AuthenticateRequest(如果有朋友不明白这个执行过程,可以通过调试中设置多个断点捕获事件执行的顺序。如果你还不会调试,可以留言偷偷的告诉我,嘿嘿。),Application_AuthenticateRequest事件初始化一个context的Identity,其实CS提供了很多的Identity支持,包括Microsoft passport,但是目前的版本中使用的是默认值System.Web.Security.FormsIdentity。具体代码如下:
private void Application_AuthenticateRequest(Object source, EventArgs e)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
{
HttpContext context = HttpContext.Current;
Provider p = null;
ExtensionModule module = null;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// If the installer is making the request terminate early
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
if (CSConfiguration.GetConfig().AppLocation.CurrentApplicationType == ApplicationType.Installer) {
return;
}
// Only continue if we have a valid context
//
if ((context == null) || (context.User == null))
return;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
try
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
// Logic to handle various authentication types
//
switch(context.User.Identity.GetType().Name.ToLower())
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Microsoft passport
case "passportidentity":
p = (Provider) CSConfiguration.GetConfig().Extensions["PassportAuthentication"];
module = ExtensionModule.Instance(p);
if(module != null)
module.ProcessRequest();
else
goto default;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Windows
case "windowsidentity":
p = (Provider) CSConfiguration.GetConfig().Extensions["WindowsAuthentication"];
module = ExtensionModule.Instance(p);
if(module != null)
module.ProcessRequest();
else
goto default;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Forms
case "formsidentity":
p = (Provider) CSConfiguration.GetConfig().Extensions["FormsAuthentication"];
module = ExtensionModule.Instance(p);
if(module != null)
module.ProcessRequest();
else
goto default;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Custom
case "customidentity":
p = (Provider) CSConfiguration.GetConfig().Extensions["CustomAuthentication"];
module = ExtensionModule.Instance(p);
if(module != null)
module.ProcessRequest();
else
goto default;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
default:
CSContext.Current.UserName = context.User.Identity.Name;
break;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
}
catch( Exception ex )
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
CSException forumEx = new CSException( CSExceptionType.UnknownError, "Error in AuthenticateRequest", ex );
forumEx.Log();
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
throw forumEx;
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// // Get the roles the user belongs to
// //
// Roles roles = new Roles();
// roles.GetUserRoles();
}
再下来是Application_AuthorizeRequest事件被触发,事件代码如下:
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
private void Application_AuthorizeRequest (Object source, EventArgs e) {
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
if (CSConfiguration.GetConfig().AppLocation.CurrentApplicationType == ApplicationType.Installer)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
//CSContext.Create(context);
return;
}
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
HttpApplication application = (HttpApplication)source;
HttpContext context = application.Context;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSContext csContext = CSContext.Current;
//bool enableBannedUsersToLogin = CSContext.Current.SiteSettings.EnableBannedUsersToLogin;
// // If the installer is making the request terminate early
// if (csContext.ApplicationType == ApplicationType.Installer) {
// return;
// }
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
//csContext.User = CSContext.Current.User;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSEvents.UserKnown(csContext.User);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
ValidateApplicationStatus(csContext);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Track anonymous users
//
Users.TrackAnonymousUsers(context);
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
// Do we need to force the user to login?
//
if (context.Request.IsAuthenticated)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
string username = context.User.Identity.Name;
if (username != null)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
string[] roles = CommunityServer.Components.Roles.GetUserRoleNames(username);
if (roles != null && roles.Length > 0)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
csContext.RolesCacheKey = string.Join(",",roles);
}
}
}
} 在Application_AuthorizeRequest中分析关键几行代码:
1:CSContext csContext = CSContext.Current; //该代码取出在前一个事件中保存在LocalDataStoreSlot中的Context,说明白点就是从内存中取出之前保存的一些数据。
2:CSEvents.UserKnown(csContext.User); //这里触发了一个UserKnown事件,涉及到CS中大量使用委托与事件的一个类CSApplication(CSApplication.cs文件),后续对这个类做专题分析,这里只要先了解该事件起到判断登陆用户是否ForceLogin以及登录的帐户是否是禁用就可以了(把对user的判断移入Application_AuthorizeRequest事件处理程序中是很好的一种处理方法)
3:ValidateApplicationStatus(csContext); //判断论坛、blog、相册是否被禁用,如果登录用户的角色不为IsAdministrator,就跳转到相应的禁用警告页面,如Blog被禁用即跳转到BlogsDisabled.htm页面显示。
4:Users.TrackAnonymousUsers(context); //如果是匿名用户,在这个方法中跟踪记录。
处理完上面三个事件后,CS将开始处理请求页面中的具体业务逻辑,如果用户请求的是登录页面,接下来就处理登录页面需要的业务逻辑和呈现,当然这里还会触发一系列其他事件,因为这些事件没有在这里定义我们暂时不做考虑。要说明一点,HttpModule在整个web请求到响应完成过程中都没有退出进程,而是处于监控状态。Application_OnError正是处于其监控范围下的一个事件,一旦有Exception或者继承Exception的类被异常抛出,HttpModule就捕获它,之后就可以根据Exception中ExceptionType值统一处理这些不同的错误信息。CS中就是这样实现错误处理的,具体的我们看一下代码:
private void Application_OnError (Object source, EventArgs e)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gif)
{
HttpApplication application = (HttpApplication)source;
HttpContext context = application.Context;
CSException csException = context.Server.GetLastError() as CSException;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
if(csException == null)
csException = context.Server.GetLastError().GetBaseException() as CSException;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
try
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
if (csException != null)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
switch (csException.ExceptionType)
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
case CSExceptionType.UserInvalidCredentials:
case CSExceptionType.AccessDenied:
case CSExceptionType.AdministrationAccessDenied:
case CSExceptionType.ModerateAccessDenied:
case CSExceptionType.PostDeleteAccessDenied:
case CSExceptionType.PostProblem:
case CSExceptionType.UserAccountBanned:
case CSExceptionType.ResourceNotFound:
case CSExceptionType.UserUnknownLoginError:
case CSExceptionType.SectionNotFound:
csException.Log();
break;
}
}
else
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
{
Exception ex = context.Server.GetLastError();
if(ex.InnerException != null)
ex = ex.InnerException;
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
csException = new CSException(CSExceptionType.UnknownError, ex.Message, context.Server.GetLastError());
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
System.Data.SqlClient.SqlException sqlEx = ex as System.Data.SqlClient.SqlException;
if(sqlEx == null || sqlEx.Number != -2) //don't log time outs
csException.Log();
}
}
![](https://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gif)
catch{} //not much to do here, but we want to prevent infinite looping with our error handles
![](https://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif)
CSEvents.CSException(csException);
} 当抛出Exception后,CS开始处理Application_OnError,根据抛出的Exception的ExceptionType类型不同做不同的处理(ForumExceptionType.cs中定义所有的CS ExceptionType)。随后调用Log()保存错误信息到数据库中,以便管理员跟踪这些错误的原因。这里还有重要的一句:CSEvents.CSException(csException)它触发了2个事件类CSCatastrophicExceptionModule与CSExceptionModule中的处理程序,与Application_AuthorizeRequest中UserKnown处理机制是一样的,会在以后的专题讨论。只要知道这里会执行RedirectToMessage方法,把页面重新定向到一个友好的错误显示页即可,如下图所示:
![](https://images.cnblogs.com/cnblogs_com/ugoer/%7B0BC9644C-BF29-4E96-9FB1-133375725598%7D0.jpg)
至此,CSHttpModule类已经全部分析完毕。在CS里还有另外两个HttpModule,属于Membership范畴,由于CS引用的是Membership的程序集无非进行内部的运行细节分析,但是工作原理与CSHttpModule是一致的,当你真正理解CSHttpModule的时候要去分析其他HttpModule也就不在话下了。希望我的这些分析能对你有帮助。