Question

Since I started using MSBuild for our projects, I’ve created several .proj scripts that are shared by several projects in our repository. All these shared scripts reside in a single directory.

So far I’ve been referring to the shared scripts by using a relative path, something like this:

<MSBuild Projects="..\..\common\build\MyScriptA.proj" Properties="ABC=XYZ"/>

However, every project also imports a common .proj script like so:

<Import Project="..\..\common\build\CommonImports.proj"/>

which <Import>s several other things and defines some properties.

This morning I thought I could replace the relative path with a variable, perhaps $(CommonDir), which would be defined by importing the CommonImports.proj mentioned above. This would enable me to call the common tasks like this:

<MSBuild Projects="$(CommonDir)\MyScriptA.proj" Properties="ABC=XYZ"/>

However, I can’t figure out a way to define this $(CommonDir) variable in such a way as to make it work in all other MSBuild scripts that import CommonImports.proj, regardless of their location.

This question offers several ways of creating a property containing an absolute path from a relative path, but none of those seem to work if all I do is <Import> the script defining the property.

Question 1: I’m fairly new to MSBuild; is there a better way of creating a “library” of reusable .proj scripts I could run via the <MSBuild> task? I am aware of $(MSBuildExtensionsPath), however I would like the common tasks to reside in my checkout so that our build machine would automatically get the latest versions of the common tasks whenever it performs a checkout.

Question 2: How do I define $(CommonDir) inside CommonImports.proj so as to make it contain the absolute path to the directory containing CommonImports.proj?

Answer 1

Here’s what’s worked best for us.

First, check in all reusable stuff into a /common/build/ directory in the VCS.

Then, add a /common/build/CommonImports.proj, looking something like this:

<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003"
         ToolsVersion="4.0">
  <Import Project="$(MSBuildExtensionsPath)\MSBuildCommunityTasks\MSBuild.Community.Tasks.Targets"/>
  <Import Project="ILMerge.proj"/>
  <Import Project="Mage.proj"/>
  <Import Project="InnoSetup.proj"/>
  <UsingTask TaskName="RT.Tasks.AssemblyVersion" AssemblyFile="Tasks\Release\RT.Tasks.dll"/>
  <UsingTask TaskName="RT.Tasks.WaitForProcessesToTerminate" AssemblyFile="Tasks\Release\RT.Tasks.dll"/>
  <PropertyGroup>
    <BuildSingleProj>$(Root)\common\build\BuildSingle.proj</BuildSingleProj>
  </PropertyGroup>
</Project>

This imports a few projects and tasks that everything uses, and defines a property group that is shared by everything. Then, add this in every build script:

<PropertyGroup>
  <Root>..\..</Root>
  [... other global properties ...]
</PropertyGroup>
<Import Project="$(Root)\common\build\CommonImports.proj"/>