In an existing ASP.NET MVC application I've added WebAPI. I've used most of the template code that's generated from a brand new project.
I'm facing some issues concerning authentication. In order to avoid the normal login procedure for the api I've added:
config.SuppressDefaultHostAuthentication();
config.Filters.Add(new HostAuthenticationFilter(OAuthDefaults.AuthenticationType));
as per the default template.
However, I get an error calling my api stating: "No OWIN authentication manager is associated with the request."
I found out that this is caused because there's a custom HTTP module active. Removing the module from the web.config makes the API work. However the 'normal' web application needs this module.
Is there a way to let the HTTP module coexist with the owin authentication?
The Module is defined like this:
public class MGPContextInitializerModule : IHttpModule
{
public void Init(HttpApplication context)
{
if (context != null)
{
context.AcquireRequestState += AcquireRequestState;
context.BeginRequest += new EventHandler(BeginRequest);
}
}
private void AcquireRequestState(object sender, EventArgs e)
{
if (HttpContext.Current.Session != null)
{
InitializeUserCulture(new HttpContextWrapper(HttpContext.Current).GetSessionID());
}
}
private void BeginRequest(object sender, EventArgs e)
{
InitializeCustomer((HttpApplication)sender);
}
private static void InitializeInstantie(HttpApplication application)
{
HttpContextBase contextBase = new HttpContextWrapper(application.Context);
RouteData routeData = RouteTable.Routes.GetRouteData(contextBase);
if (routeData != null)
{
var customer = routeData.Values["customer"];
if (customer != null)
{
Initializer.InitializeCustomer(customer.ToString());
}
}
}
}
I'm using an HttpModule to try and redirect users to the login page if they're not authenticated, but for some reason it's just endlessly redirecting the page without landing anywhere.
Here's the module:
using System;
using System.Web;
using System.Web.Security;
public class AuthenticationModule : IHttpModule
{
public AuthenticationModule()
{
}
public string ModuleName
{
get
{
return "AuthenticationModule";
}
}
public void Init(HttpApplication app)
{
app.BeginRequest += (new EventHandler(Application_BeginRequest));
}
private void Application_BeginRequest(object source, EventArgs e)
{
HttpApplication app = (HttpApplication)source;
HttpContext context = app.Context;
HttpRequest request = context.Request;
HttpResponse response = context.Response;
if (!request.IsAuthenticated && !request.RawUrl.Contains(FormsAuthentication.LoginUrl))
{
FormsAuthentication.RedirectToLoginPage();
}
}
public void Dispose() { }
}
I don't recall having ever worked with HttpModules before, so I'm not sure what's not working.
How can I fix this?
request.RawUrl is the URL I entered into the browser. Your check request.RawUrl.Contains(FormsAuthentication.LoginUrl) is case sensitive.
Additionally there are no checks for ressources. So each request for images, css files etc. will redirect to login page. You need to check if authentication is required for the ressource being called.
Edit (hit the save button to early)
Additionally I would do it on AuthenticateRequest
I have created an HttpModule so that Whenever I type "localhost/blabla.html" in the browser, it will redirect me to www.google.com (this is just an example, it's really to redirect requests coming from mobile phones)
My Questions are :
1) How do I tell IIS(7.0) to redirect each request to the "HttpModule" so that it is independent of the website. I can change the web.config but that's it.
2) Do I need to add the .dll to the GAC? If so, How can I do that?
3) The HttpModule code uses 'log4net' . do I need to add 'log4net' to the GAC as well?
Thanks
P.S. the site is using .net 2.0.
You can use request object in BeginRequest event
public class MyHttpModule : IHttpModule
{
public void Init(HttpApplication context)
{
context.BeginRequest += new EventHandler(this.context_BeginRequest);
}
private void context_BeginRequest(object sender, EventArgs e)
{
HttpApplication application = (HttpApplication)sender;
HttpContext context = application.Context;
//check here context.Request for using request object
if(context.Request.FilePath.Contains("blahblah.html"))
{
context.Response.Redirect("http://www.google.com");
}
}
}
I have two production websites that have similar content. One of these websites needs to be indexed by search engines and the other shouldn't. Is there a way of adding content to the response given to the client using the HttpModule?
In my case, I need the HttpModule to add to the response sent to the when the module is active on that particular web.
You'd probably want to handle the PreRequestHandlerExecute event of the application as it is run just before the IHttpHandler processes the page itself:
public class NoIndexHttpModule : IHttpModule
{
public void Dispose() { }
public void Init(HttpApplication context)
{
context.PreRequestHandlerExecute += AttachNoIndexMeta;
}
private void AttachNoIndexMeta(object sender, EventArgs e)
{
var page = HttpContext.Current.CurrentHandler as Page;
if (page != null && page.Header != null)
{
page.Header.Controls.Add(new LiteralControl("<meta name=\"robots\" value=\"noindex, follow\" />"));
}
}
}
The other way of doing it, is to create your own Stream implementation and apply it through Response.Filters, but that's certainly trickier.
I could really do with updating a user's session variables from within my HTTPModule, but from what I can see, it isn't possible.
UPDATE: My code is currently running inside the OnBeginRequest () event handler.
UPDATE: Following advice received so far, I tried adding this to the Init () routine in my HTTPModule:
AddHandler context.PreRequestHandlerExecute, AddressOf OnPreRequestHandlerExecute
But in my OnPreRequestHandlerExecute routine, the session state is still unavailable!
Thanks, and apologies if I'm missing something!
Found this over on the ASP.NET forums:
using System;
using System.Web;
using System.Web.Security;
using System.Web.SessionState;
using System.Diagnostics;
// This code demonstrates how to make session state available in HttpModule,
// regardless of requested resource.
// author: Tomasz Jastrzebski
public class MyHttpModule : IHttpModule
{
public void Init(HttpApplication application)
{
application.PostAcquireRequestState += new EventHandler(Application_PostAcquireRequestState);
application.PostMapRequestHandler += new EventHandler(Application_PostMapRequestHandler);
}
void Application_PostMapRequestHandler(object source, EventArgs e)
{
HttpApplication app = (HttpApplication)source;
if (app.Context.Handler is IReadOnlySessionState || app.Context.Handler is IRequiresSessionState) {
// no need to replace the current handler
return;
}
// swap the current handler
app.Context.Handler = new MyHttpHandler(app.Context.Handler);
}
void Application_PostAcquireRequestState(object source, EventArgs e)
{
HttpApplication app = (HttpApplication)source;
MyHttpHandler resourceHttpHandler = HttpContext.Current.Handler as MyHttpHandler;
if (resourceHttpHandler != null) {
// set the original handler back
HttpContext.Current.Handler = resourceHttpHandler.OriginalHandler;
}
// -> at this point session state should be available
Debug.Assert(app.Session != null, "it did not work :(");
}
public void Dispose()
{
}
// a temp handler used to force the SessionStateModule to load session state
public class MyHttpHandler : IHttpHandler, IRequiresSessionState
{
internal readonly IHttpHandler OriginalHandler;
public MyHttpHandler(IHttpHandler originalHandler)
{
OriginalHandler = originalHandler;
}
public void ProcessRequest(HttpContext context)
{
// do not worry, ProcessRequest() will not be called, but let's be safe
throw new InvalidOperationException("MyHttpHandler cannot process requests.");
}
public bool IsReusable
{
// IsReusable must be set to false since class has a member!
get { return false; }
}
}
}
HttpContext.Current.Session should Just Work, assuming your HTTP Module isn't handling any pipeline events that occur prior to the session state being initialized...
EDIT, after clarification in comments: when handling the BeginRequest event, the Session object will indeed still be null/Nothing, as it hasn't been initialized by the ASP.NET runtime yet. To work around this, move your handling code to an event that occurs after PostAcquireRequestState -- I like PreRequestHandlerExecute for that myself, as all low-level work is pretty much done at this stage, but you still pre-empt any normal processing.
Accessing the HttpContext.Current.Session in a IHttpModule can be done in the PreRequestHandlerExecute handler.
PreRequestHandlerExecute: "Occurs just before ASP.NET starts executing an event handler (for example, a page or an XML Web service)." This means that before an 'aspx' page is served this event gets executed. The 'session state' is available so you can knock yourself out.
Example:
public class SessionModule : IHttpModule
{
public void Init(HttpApplication context)
{
context.BeginRequest += BeginTransaction;
context.EndRequest += CommitAndCloseSession;
context.PreRequestHandlerExecute += PreRequestHandlerExecute;
}
public void Dispose() { }
public void PreRequestHandlerExecute(object sender, EventArgs e)
{
var context = ((HttpApplication)sender).Context;
context.Session["some_sesion"] = new SomeObject();
}
...
}
If you're writing a normal, basic HttpModule in a managed application that you want to apply to asp.net requests through pages or handlers, you just have to make sure you're using an event in the lifecycle after session creation. PreRequestHandlerExecute instead of Begin_Request is usually where I go. mdb has it right in his edit.
The longer code snippet originally listed as answering the question works, but is complicated and broader than the initial question. It will handle the case when the content is coming from something that doesn't have an ASP.net handler available where you can implement the IRequiresSessionState interface, thus triggering the session mechanism to make it available. (Like a static gif file on disk). It's basically setting a dummy handler that then just implements that interface to make the session available.
If you just want the session for your code, just pick the right event to handle in your module.
Since .NET 4.0 there is no need for this hack with IHttpHandler to load Session state (like one in most upvoted answer). There is a method HttpContext.SetSessionStateBehavior to define needed session behaviour.
If Session is needed on all requests set runAllManagedModulesForAllRequests to true in web.config HttpModule declaration, but be aware that there is a significant performance cost running all modules for all requests, so be sure to use preCondition="managedHandler" if you don't need Session for all requests.
For future readers here is a complete example:
web.config declaration - invoking HttpModule for all requests:
<system.webServer>
<modules runAllManagedModulesForAllRequests="true">
<add name="ModuleWithSessionAccess" type="HttpModuleWithSessionAccess.ModuleWithSessionAccess, HttpModuleWithSessionAccess"/>
</modules>
</system.webServer>
web.config declaration - invoking HttpModule only for managed requests:
<system.webServer>
<modules>
<add name="ModuleWithSessionAccess" type="HttpModuleWithSessionAccess.ModuleWithSessionAccess, HttpModuleWithSessionAccess" preCondition="managedHandler"/>
</modules>
</system.webServer>
IHttpModule implementation:
namespace HttpModuleWithSessionAccess
{
public class ModuleWithSessionAccess : IHttpModule
{
public void Init(HttpApplication context)
{
context.BeginRequest += Context_BeginRequest;
context.PreRequestHandlerExecute += Context_PreRequestHandlerExecute;
}
private void Context_BeginRequest(object sender, EventArgs e)
{
var app = (HttpApplication)sender;
app.Context.SetSessionStateBehavior(System.Web.SessionState.SessionStateBehavior.Required);
}
private void Context_PreRequestHandlerExecute(object sender, EventArgs e)
{
var app = (HttpApplication)sender;
if (app.Context.Session != null)
{
app.Context.Session["Random"] = $"Random value: {new Random().Next()}";
}
}
public void Dispose()
{
}
}
}
Try it: in class MyHttpModule declare:
private HttpApplication contextapp;
Then:
public void Init(HttpApplication application)
{
//Must be after AcquireRequestState - the session exist after RequestState
application.PostAcquireRequestState += new EventHandler(MyNewEvent);
this.contextapp=application;
}
And so, in another method (the event) in the same class:
public void MyNewEvent(object sender, EventArgs e)
{
//A example...
if(contextoapp.Context.Session != null)
{
this.contextapp.Context.Session.Timeout=30;
System.Diagnostics.Debug.WriteLine("Timeout changed");
}
}