Dot Net Matters

June 15, 2005

@ 09:03 AM

Introduction to Mono - ASP.NET with XSP and Apache

This article is the second article in the series of introductory articles that I am writing about Mono, the "open source development platform based on the .NET framework". In this article we'll take a look at how to get going with ASP.NET on the Mono platform. Although ASP.NET is not part of the ECMA and ISO standards mentioned in the first article[^], it is still one of the major selling points of the .NET platform and provides an extremely flexible and powerful platform for developing web applications and Web Services upon. Although you can develop ASP.NET applications for Mono on a number of different operating systems this article will focus mainly on Linux, although, in saying that, I do look briefly at getting XSP running on Windows. The reason I will concentrate on ASP.NET on Linux is because those people interested in ASP.NET on Windows have an extremely powerful option at their fingertips in the form IIS and I would whole heartedly recommend using it for ASP.NET on Windows.

Where does ASP.NET stand with Mono??

The latest stable version of Mono, version 1.0.5, has a fully functional implementation of ASP.NET. This includes full support for ASP.NET Web Forms and Web Services. This essentially means that more or less any ASP.NET application that you have developed using with the .NET Framework will work with Mono. Obviously there might be changes needed, such as data access changes, removal of any reliance on .NET Framework BCL types that are not implemented in Mono yet, and also the removal of any code that makes use of platform invoke and so on. At this stage the ASP.NET support in Mono can be considered as excellent and a lot of publicly available web applications already make use of Mono's ASP.NET support. According to the Mono site the Mono Web Services stack is being used in the source control application Vault[^] by SourceGear and aspects of Mono's ASP.NET implementation are also used in the Virtuoso[^] product from OpenLink.

What are XSP and mod_mono?

There isn't much point in developing web applications and Web Services if you have no way of serving them, is there? Traditionally you would use IIS to host ASP.NET applications on Windows, although there are some other free ASP.NET web servers available such as Cassini[^]. However, when using ASP.NET with Mono you have two main options as regards which web server to host your ASP.NET applications in:

XSP
Apache

In this article we look at using both XSP (on Windows and Linux) and Apache to host your ASP.NET web applications and Web Services.

XSP

XSP is a "light-weight web server" capable of hosting and serving ASP.NET applications. It is written using C#, making extensive use of the classes in the System.Web namespace, and the source for XSP is available for download from the Mono download page[^] . It is also interesting to note that the XSP web server runs on both the Mono runtime and also on the .NET runtime which means that if you are looking for a light-weight ASP.NET web server for Windows but you don't want to use or you don't care about Mono, you could still make use of XSP. The Let's get XSP up and running section runs through how to install and use XSP on Windows and Linux.

Apache

Apache is probably the de facto standard web server used on Linux. Apache makes extensive use of modules to enable it to host and serve web applications developed in a multitude of different web programming languages and scripts. Those of you familiar with IIS but not so familiar with Apache can think of these modules as the equivalent of ISAPI extensions. So, by this stage I assume you can guess how Apache can host and serve ASP.NET application? Yep, using an Apache module. This module, called mod_mono, allows Apache to serve ASP.NET pages "by proxying the requests to a slightly modified version of XSP called mod-mono-server". mod-mono-server is installed when you install XSP. At the time of writing the current version of the mod_mono module for Apache only works for Apache on Linux and not for Apache on Windows. For this reason, when we look at ASP.NET on Apache in the Apache with mod_mono section we only look at it in the context of Linux. If you do wish to serve ASP.NET content from Apache on Windows have a look at this article[^] on CP, which shows how to use configure Apache to use Cassini to serve ASP.NET content or have a look at the Apache HTTP CLI[^] project.

What you need to know

This article assumes that you have Mono installed and working on your desired platform. The first article in this series, Introduction to Mono - Your first Mono app[^], explains how to get Mono up and running on Windows and Linux so if you have not yet done so have a look over that article. I also assume that you are familiar with ASP.NET and the semantics of ASP.NET programming as this article primarily looks at getting ASP.NET working with XSP and Apache, not at ASP.NET programming.

Lets get XSP up and running

In this section we will look at getting XSP up and running on both Windows and on Linux. Installing and running on Windows is "tackled" first simply because I want to get it out of the way and because chances are that you already have XSP on Windows considering the fact that you should have Mono already installed. Then it's on to Linux and getting XSP up and running there. To be honest, if you already have Mono running on Linux, which you should as it's one of the prerequisites for this article, then it should be relatively easy.

XSP on Windows

The first article[^] in this series ran through installing Mono on Windows. It mentioned that during the install process the installer gives you the option to select which components to install. By default, XSP is installed along with Mono but if you decided to not install XSP during the install then the easiest way to get XSP installed is to uninstall Mono and then reinstall it again. Here are the steps explaining how to install Mono and XSP on a Windows 2000 or above machine:

Download the Mono Windows Installer from the Mono download page. The file I am working off is http://www.go-mono.com/archive/1.0.5/windows/mono-1.0.5-gtksharp-1.0.5-win32-0.1.exe
The installer is a standard Windows installer so you can simply run it once it is downloaded by doubling clicking on it.
Once the installer begins, click on next to go to the License Agreement page.
You'll probably notice on the License Agreement page that there are a number of different Licenses that apply to the different components of the install. While I understand that most people simply agree and click on next, it would be irresponsible of me if I didn't recommend that you read the License Agreement before agreeing to it.
Once you pass the License Agreement section you are presented with some general information about the install.
Click on Next and select the install location.
Click on Next again to bring you to the Select Components page. You are free to customize your installation but make sure that you install XSP. As I will be using all the components of this install in other articles in this series I would suggest that you accept the default "Full installation".
Click on Next again and you can customize the name of Mono folder that appears in the Start Menu.
The installer will now ask you which port you want the XSP web server to listen on. Generally this will be port 8088 but you can change it to any free port on your system. When you are ready click on Next.
Finally, click on Install to install and configure Mono and XSP on your Windows machine.

Those of you who read the first article will notice that I more or less ripped the instructions from that one... I'm not lazy, just no point in rewriting what has already been said! The next step in using XSP on Windows is to run it. The Running XSP section explains how to run the XSP web server and looks at some of the command line options that you can use to alter it's default behaviour.

XSP on Linux

As with installing Mono on Linux, which we examined in the previous article, things are slightly more complicated on Linux then on Windows. However, as I already mentioned, if you have Mono installed, then getting XSP installed is going to be a breeze for you. I'm installing XSP on the same systems that I used for installing Mono in the previous article. A quick recap of what exactly I used is in order so: I used Microsoft Virtual PC 2004 and created two identical virtual PCs. I then installed SuSE 9.2 Professional with ACPI disabled and I used the default package selection when installing. In the last article I went through how to install Mono using the pre-built packages from the Mono site and also I ran through how to install Mono from source. So for the purposes of this article I will be installing XSP on a SuSE 9.2 Professional with the default package selection with Mono 1.0.5 installed along with any additional packages or programs that were installed during the Mono install.

In this article we will again look at installing from both the pre-build packages and from the source.

XSP using pre-built packages

As I am sure you can remember from the first article (if you read it that is), installing using the pre-built packages from the Mono site is one of the easiest ways of getting Mono up and running. The same thing applies to getting XSP up and running. So, head on over to the Mono download page (http://www.mono-project.com/downloads/index.html[^]) and see if there are pre-built packages for your particular Linux distribution or if there are packages for a distribution that you know will be compatible with your distribution. If there isn't a package that will work with your distribution just jump ahead to the XSP from source section where I will run through installing XSP from the source which is a simple process.

Lets get going:

On the Mono download page, click on the "Packages" link beside the Linux distribution that you believe to be compatible with your distribution. I simply selected the link beside SuSE 9.2
This should bring you to a page which lists a lot of different packages that have been compiled and packaged for that particular Linux distribution.
Before we install XSP we need to install two other pre-built packages. These packages include files that XSP is dependent upon.
The first package we need to install is the "Database Core" package that can be found in the database section. The exact name of the package will vary depending on the packages link that you selected initially but in general the name will start with "mono-data". The package I downloaded for SuSE 9.2 was http://www.go-mono.com/archive/1.0.5/suse-92-i586/mono-data-1.0.5-1.ximian.10.4.i586.rpm.
Once you have downloaded this file, open it and it will launch the package manager for your distribution. At this stage simply follow the instructions to install the package.
After you have installed the "mono-data" package you now need to download the "mono-web" package which will be listed under the "Web Applications, Web Services" section. The package I downloaded for SuSE 9.2 was http://www.go-mono.com/archive/1.0.5/suse-92-i586/mono-web-1.0.5-1.ximian.10.4.i586.rpm.
Next, as with the "mono-data" package, simply open the package and follow the instructions to install it using the package manager of your distribution.
Finally we are ready to install XSP itself. So just head back to the "Web Applications, Web Services" section of the package download page and download the "xsp" package. The package I got was http://www.go-mono.com/archive/1.0.5/suse-92-i586/xsp-1.0.5-1.ximian.10.1.i586.rpm.
As with the two previous packages, simply open it and follow the instructions of your package manager to install XSP.
All going well, you should have XSP installed now!

At this stage XSP should be installed on your system so you can jump ahead to the Running XSP section which gives an overview of how to use XSP. If you are having difficulty installing XSP from the packages have a look at the next section, "XSP from source", which might be able to help you out.

XSP from source

Installing XSP from the source should be breeze if you have installed Mono from source by following the instructions in the previous article[^]. Let's jump straight in:

The first thing you need to do is download the source. Once again, head on over to the Mono download page at http://www.mono-project.com/downloads/index.html[^].
In the source code section click on and download the "XSP web server". I downloaded http://www.go-mono.com/archive/1.0.5/xsp-1.0.5.tar.gz.
Once the file has been downloaded, go to a console for the remainder of the process
You can decompress the downloaded file using the command tar -xvzf xsp-1.0.5.tar.gz where xsp-1.0.5.tar.gz is the name of the file you downloaded.
Next, switch to the directory where the source code has been decompressed to by typing cd xsp-1.0.5 or cd followed by the name of the directory that you decompressed the file to if it is different from mine.
Now, before we can compile the source you need to configure the make files. To do this simply type ./configure --prefix=/usr. This will take a bit of time. I am assuming here that there were no errors and that the ./configure --prefix=/usr went ahead without issue.
When the the ./configure --prefix=/usr completes you are free to go ahead and compile and install the source.
To actually compile the XSP source you need to run the make command.
Root privileges are required for the next step. If you have just installed Linux as a standalone machine you can usually give your account root privileges by typing the sudo bash command and entering the root password.
Finally, to install, for lack of a better word, simply run the make install command. This will deploy the compiled binaries, libraries and other bits and pieces to the correct directories.