Getting started with “FAKE – F# Make”– Get rid of the noise in your build scripts.

[Last updated: Jan 9, 2013]

In this tutorial I will describe how you can set up a complete build infrastructure with “FAKE – F# Make”. You will learn how to:

• install the latest FAKE version
• automatically compile your C# or F# projects
• automatically resolve nuget dependencies
• automatically run NUnit UnitTests on your projects
• zip the output to a deployment folder

Install F#

“FAKE – F# Make” is completely written in F# and all build scripts will also be written in F#, but this doesn’t imply that you have to learn programming in F#. In fact the “FAKE – F# Make” syntax is hopefully very easy to learn. But if you need to you can use the complete power of F# and the .NET Framework.

Download Calculator Sample

Now download the latest FAKE-Calculator.zip from the FAKE project site. This sample includes 3 tiny projects and has basically the following structure:

• src\app
  • Calculator (Command line)
  • CalculatorLib (Class library)
• src\test
  • Test.CalculatorLib
• tools
  • NUnit
  • FxCop
• build.bat
• build.fsx
• completeBuild.bat
• completeBuild.fsx
• Calculator.sln

Getting “FAKE – F# Make” started

In the root of the project you will find a build.bat file:

If you run this batch file from the command line then the latest FAKE version will be downloaded via nuget and your first FAKE script (build.fsx) will be executed. If everything works fine you will get the following output:

Now open the build.fsx with Visual Studio. It should look like this:

As you can see the code is really simple. The first line includes the FAKE library and is vital for all FAKE build scripts.

After this header the Default target is defined. A target definition contains of two important parts. The first is the name of the target (here “Default”) and the second is an action (here a simple trace of “Hello world”).

The last line runs the “Default” target – which means it executes the defined action of the target.

Cleaning the last build output

A typical first step in most build scenarios is to clean the output of the last build. We can achieve this by modifying the build.fsx to the following:

We introduced some new concepts in this snippet. At first we defined a global property called “buildDir” with the relative path of a temporary build folder.

In the Clean target we use the CleanDir task to clean up this build directory. This simply deletes all files in the folder or creates the directory if necessary.

In the dependencies section we say that the Default target has a dependency on the Clean target. In other words Clean is a prerequisite of Default and will be run before the execution of Default:

Building the application

In the next step we want to compile our C# libraries, which means we want to compile all csproj-files under /src/app with MSBuild:

We defined a new build target named “BuildApp” which compiles all csproj-files with the MSBuild task and the build output will be copied to buildDir.

In order to find the right project files “FAKE – F# Make” scans the folder src/app/ and all subfolders with the given pattern. Therefore a similar FileSet definition like in NAnt or MSBuild (see project page for details) is used.

In addition the target dependencies are modified again. Now Default is dependent on BuildApp and BuildApp needs Clean as a prerequisite.

This means the execution order is: Clean ==> BuildApp ==> Default.

Building Test projects

Now our main application will be built automatically and it’s time to build the test project. We use the same concepts as before:

This time we defined a new target “BuildTest” which compiles all C# projects below src/test/ in Debug mode and we put the target into our build order.

If we run build.bat again we get an error like this:

The problem is that we didn’t download the NUnit package from nuget. So let’s fix this in the build script:

With this simple command FAKE will use nuget.exe to install all the package dependencies.

Testing the test assemblies with NUnit

Now all our projects will be compiled and we can use Fake’s NUnit task in order to let NUnit test our assembly:

Our new Test target scans the test directory for test assemblies and runs them with the NUnit runner. The mysterious part (fun p –> …) simply overrides the default parameters of the NUnit task and allows to specify concrete parameters..

Deploying a zip file

Now we want to deploy a *.zip file containing our application:

The new Deploy target scans the build directory for all files. The result will be zipped to /deploy/Calculator.zip via the Zip task.

What’s next?

Now you are ready to write your own “FAKE – F# Make” build scripts. If you have any questions or suggestions feel free to comment on this post.

In the next article I will show how we can add FxCop to our build in order to check specific naming rules.

Original article: Getting started with “FAKE – F# Make” – Get rid of the noise in your build scripts.

©2013 Rash thoughts about .NET, C#, F# and Dynamics NAV.. All Rights Reserved.