I would like to know if there is any way I can check if the request for static files like images/css etc is handled from asp.net pipeline or not.
I have set runAllManagedModules=false in web.config and added ignore routes as well.
The load times have come down. Which indicates that the requests are probably not passing through the asp.net pipeline.
However, is there a way I can ascertain the same?
Browsers i Used: IE/ Firefox
If request goes through ASP.NET request pipeline, it should call all the registered http-modules.
Add custom http-module (if you don't have one).
Put breakpoint inside.
Run app in debug mode.
Initiate request of any static content.
If breakpoint is reached, request probably goes through ASP.NET pipeline. To make sure, you can check the url of the request in debug mode.
I have code in my project which changes the URL containing the text as querystring to number to get the data from the database. I am checking the querystring in page load and if it contains the name rather than the number I am mapping it to the numeric key. Now I have to execute the page life cycle again. I had two choice either use the
Response.Redirect
but I do not want the URL in the client browser to change so I went with the
Server.Transfer
The problem I started facing is that I have a custom httpmodule which is used to log the URLs in the database. I realized that
BeginRequest
in the http module is not firing after the
Server.Transfer
My application is working fine in the case of
Response.Redirect.
I am not sure how and why Server.Transfer is skipping my HttpModule and if it is how it works ?
Server.Transfer is a completely server side mechanism - it instantiates the new Page class based on the path to .aspx file and transfers the execution there (including all state information for the built-in objects). There is no new request and nothing goes again through the pipeline (so among other things HttpModules are not re-executed), as the hosting part is interested this is still the same request - the response has just been created from different page than it was originally planed.
Response.Redirect falls to standard HTTP mechanism. On server side it throws an exception to break the current execution pipeline and return an 3xx status code. The browser then issues new request for the resource under the new URL. Both requests go through full pipeline on the server side.
So the answer to your question boils down to the fact that HttpModules are being executed for every upcoming request but in case of Server.Transfer there is no new upcoming request.
I like to execute javascript/server side code for each and every request(*.htm,*.asp,*.aspx,*.asmx, ...) to IIS server.
Is there any way to write a isapi (dll) and register it with the iis that will accept all kind of request (*.*) and once my script is excuted, i will forward the request to appropriate isapi filter?
HttpModule might be what you are looking for. You will register your HttpModule to web.config and it will be added to pipeline, and will be executed for each request. But i dont think you can run javascript but you will be able to execute c# code on every request.
Here is msdn article , How to create HttpModule:
http://msdn.microsoft.com/en-us/library/aa719858(v=vs.71).aspx
Can someone explain in less than 2 sentences the difference between both? Yes, I know google can provide hundreds of answers but not one in 2 clear sentences:)
HttpHandler is where the request train is headed. HttpModule is a station along the way.
The two sentences:
An HttpModule will execute for every request to your application, regardless of extension, and is generally used for things like security, statistics, logging, etc.
An HttpHandler is generally associated with a specific extension, and is used for things like RSS feeds, dynamic image generation or modification, and the like.
A little more explanation if that's not completely clear:
The way I think about them - modules "plug in" to the request pipeline, whereas handlers "handle" a specific file extension. So, if you've got a site with a LoggingModule and a PdfHandler, both will execute for a request to http://example.com/sample.pdf, and the logging module alone will execute for a request to http://example.com/page.aspx.
There's a pretty clear article on the difference on MSDN: HTTP Handlers and HTTP Modules Overview
The prime and common goal of HttpHandler and HttpModule is to inject pre-processing logic before the ASP.NET request reaches the IIS Server.
ASP.NET provides two ways of injecting logic in the request pipeline;
Http Handlers:
Http Handler helps us to inject pre-processing logic based on the extension of the file name requested. ASP.NET uses HTTP handlers for implementing a lot of its own functionality.For example, ASP.NET uses handlers for processing .aspx, .asmx and trace.axd files.
example:
RSS feeds: To create an RSS feed for a Web site, you can create a handler that emits RSS-formatted XML. So when users send a request to your site that ends in .rss, ASP.NET calls your handler to process the request.
There are three steps involved in creating Handler
1. Implement IHttpHandler interface.
2. Register handler in web.config or machine.config file.
3. Map the file extension (*.arshad) to aspnet_isapi.dll in the IIS.
IHttpHandler interface has ProcessRequest method and IsReusable property which needs to be implemented.
ProcessRequest: In this method, you write the code that produces the output for the handler.
IsResuable: This property tells whether this handler can be reused or not.
You can register the handler in web.config file like this
<httpHandlers>
<add verb="*" path="*.arshad" type="namespace.classname, assemblyname" />
</httpHandlers>
Note: here we are handling any file name with extension arshad.
Http Modules:
HttpModule is an event based processor to inject pre-processing logic before the request reaches the IIS Server. ASP.NET uses HTTP Module to implement lots of its own functionality like authentication and authorization, session management and output caching etc.
ASP.NET engine emits lot of events as the request passess through the request pipeline.
Some of those events are AuthenticateRequest, AuthorizeRequest, BeginRequest, EndRequest.
By Using HttpModule you can write logic in these events. These logic get executed as the events fire and before the request reaches IIS.
There are two steps involved in creating Modules,
1. Implement IHttpModule interface
2. Register module in web.config or machine.config file
example:
Security: Using HTTP module, you can perform custom authentication or other security checks before the request reaches IIS.
HTTP handler is the process that runs in response to a request made to an ASP.NET Web application.
HTTP modules let you examine incoming and outgoing requests and take action based on the request.
HttpHandler is responsible for handling http request by extension while HttpModule is responding to application life cycle events.
Nice article aboute it HttpModule-and-HttpHandlers
Reference: INFO: ASP.NET HTTP Modules and HTTP Handlers Overview
“Modules are called before and after the handler executes. Modules enable developers to intercept, participate in, or modify each individual request. Handlers are used to process individual endpoint requests. Handlers enable the ASP.NET Framework to process individual HTTP URLs or groups of URL extensions within an application. Unlike modules, only one handler is used to process a request”.
HTTP handler is where actually compilation is done based on setting. such as if page extension is .aspx then it will compile through system.web.Ui.Pagahandlefactory. once compilation is done at HTTP handle request will go though HTTP module and IIS.
HTTP Handler
HTTP Handler is the process which runs in response to a HTTP request. So whenever user requests a file it is processed by the handler based on the extension. So, custom http handlers are created when you need to special handling based on the file name extension. Let's consider an example to create RSS for a site. So, create a handler that generates RSS-formatted XML. Now bind the .rss extension to the custom handler.
HTTP Modules
HTTP Modules are plugged into the life cycle of a request. So when a request is processed it is passed through all the modules in the pipeline of the request. So generally http modules are used for:
Security: For authenticating a request before the request is handled.
Statistics and Logging: Since modules are called for every request they can be used for gathering statistics and for logging information.
Custom header: Since response can be modified, one can add custom header information to the response.
I'm experimenting with javascript and css caching in ASP.NET MVC. Is it possible to intercept calls to the server for these types of files?
For example, if a request gets to the server for
~/Scripts/Something.CurrentVersion.js
I would like to intercept this call and tell the server to return
~/Scripts/SomeOtherFile.js
Would it be possible to hook into some event or create a new module or HttpHandler to accomplish this?
Checkout these links for different ways:
http://weblogs.asp.net/rashid/archive/2009/04/28/script-and-css-management-in-asp-net-mvc.aspx
http://weblogs.asp.net/rashid/archive/2009/05/02/script-and-css-management-in-asp-net-mvc-part-2.aspx
http://www.codeproject.com/KB/aspnet/combineMinify.aspx
Yep. HttpHandler is certainly one way to go. Beware of the integration to IIS though - to have full control over mapping you have to run it in integrated mode - otherwise IIS itself will process request BEFORE it will get to the worker process