EmbeddedPageHandlerFactory - Binary-Only ASP.NET 1.1
I’m constantly looking for ways to make deployment of ASP.NET applications easier. One of the things that makes it difficult is the ASPX markup files that have to be deployed with the app. Wouldn’t it be nice not to have those? Wouldn’t it be nice to be able to drop the application .dll into the bin folder, pop in your web.config file, and let ‘er rip?
Since I work primarily in ASP.NET 1.1 right now, the solution I came up with is for ASP.NET 1.1. There is a different/better way to do this in ASP.NET 2.0 and I will be writing/posting that as I get time.
UPDATE: The ASP.NET 2.0 version is here - based on System.Web.Hosting.VirtualPathProvider.
The idea: Embed your ASPX files in your ASP.NET application assembly. To deploy the app, drop your .dll in the bin folder and set up your web.config file. At runtime, embedded ASPX pages get extracted to a temporary location and get served up from there. When the app shuts down, the temporary fileset gets cleaned up. Easy deployment, easy upgrades.
The solution: An HttpModule that does exactly that. You set your application web.config file to use the EmbeddedPageHandlerFactory and in your ASP.NET project set your ASPX files from “Content” to “Embedded Resource.” At application startup, the module will go through the assemblies you registered as containing pages and extracts the ASPX to a temporary location. A replacement for the standard PageHandlerFactory redirects requests to the temporary location so pages get served up just like usual. When the application shuts down, the temporary files get cleaned up.
Here’s a snippet of the relevant bits in web.config:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section
name="embeddedPageAssemblies"
type="System.Configuration.DictionarySectionHandler, System, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, Custom=null"
/>
</configSections>
<embeddedPageAssemblies>
<add
key="Paraesthesia.EmbeddedPageHandlerFactory.Demo"
value="Paraesthesia.EmbeddedPageHandlerFactory.Demo" />
</embeddedPageAssemblies>
<system.web>
<httpModules>
<add
name="EmbeddedPageHandlerFactory"
type="Paraesthesia.Web.UI.EmbeddedPageHandlerFactory, Paraesthesia.EmbeddedPageHandlerFactory" />
</httpModules>
<httpHandlers>
<add
verb="*"
path="*.aspx"
type="Paraesthesia.Web.UI.EmbeddedPageHandlerFactory, Paraesthesia.EmbeddedPageHandlerFactory" />
</httpHandlers>
</system.web>
</appSettings>
<add
key="Paraesthesia.Web.UI.EmbeddedPageHandlerFactory.AllowFileSystemPages"
value="false" />
<appSettings>
</configuration>
Key points:
- The
embeddedPageAssemblies
section is how you tell the module which assemblies have ASPX in them. The “key” is the name of the assembly; the “value” is the root namespace in the assembly. - The
httpModules
section is where you register the module portion of the solution. This is how the pages get extracted at app startup. - The
httpHandlers
section is where you tell all requests for ASPX files to go through the EmbeddedPageHandlerFactory and get served up from the temporary location. - The
appSettings
has an optional key for AllowFileSystemPages. Setting this to true will allow you to “override” ASPX by putting a file of the same path/name in the ASP.NET application file system. If the file exists in the app, it will be served from there. If not, it falls back to the temporary filesystem.
In your web project, change your ASPX pages in your application to be “Embedded Resource” rather than “Content.” Embedded resources get named based on namespace and file path. For example, if you have an assembly called “MyApp.Web” where the default namespace is “MyApp.Web” and you have a file at “~/Admin/Default.aspx” then when it gets embedded as a resource, it’ll be called “MyApp.Web.Admin.Default.aspx” - notice the namespace, then the path, then the file, all delimited by periods.
What the module does is look for resources that end with “.aspx” and, if it finds them, removes the namespace from the front (as specified in web.config) and substitutes out / for . to convert back to a path. In this example, “MyApp.Web.Admin.Default.aspx” would become “Admin.Default.aspx” and then “Admin/Default.aspx.”
Once the mapping is done, a temporary location is generated and the page is extracted to that location with the full relative path intact. As requests come in, the EmbeddedPageHandlerFactory will look at the request, map it into the temporary location, and serve the temporary file.
Using the appSettings
key, you can specify that you’d like to allow
pages in the actual ASP.NET filesystem to override the extracted pages.
In this case, the actual ASP.NET filesystem would be searched for
“Admin/Default.aspx” and if it is found, serve it from there just like a
standard ASP.NET application. If it isn’t found, then it’ll fall back to
look in the temporary location.
Caveats:
- This won’t work for sites that rely on file system security. I primarily work with forms authentication, so this isn’t a problem for me. It may be for you.
- This is definitely not the way you’d want to do this for .NET 2.0. This is really meant for .NET 1.1.
- It only works for ASPX. The ASCX load process is different and doesn’t pass through a handler factory like pages. The .NET 2.0 mechanism should work for any files, not just ASPX.
- This is going to be a one-shot deal. I’m not going to be posting updates or actively supporting it or anything. Take it at your own risk, your mileage may vary, etc.
- The source bundle includes the source for the EmbeddedPageHandlerFactory as well as a demo web application and unit tests.
- I wrote the unit tests using TypeMock so you’ll need to go get that if you want to build/run the tests.
- It’s totally free and open-source. Do whatcha like.