How to use XSLT to filter duplicates from another wxs file

Question

What i have

I have a problem finding duplicate components using xslt. I am using heat to harvest 2 Projects. These projects share some references (.dll files). Now heat creates 2 Fragments

1. ConfiguratorFiles.wxs
2. ServiceFiles.wxs

The ConfiguratorFiles.wxs gets created first and use a totaly basic filter:

  <xsl:template match="@*|node()">
    <xsl:copy>
      <xsl:apply-templates select="@*|node()"/>
    </xsl:copy>
  </xsl:template>

  <xsl:key name="service-search" match="wix:Component[contains(wix:File/@Source, '.pdb')]" use="@Id" />
  <xsl:template match="wix:Component[key('service-search', @Id)]"/>
  <xsl:template match="wix:ComponentRef[key('service-search', @Id)]" />

The output is totally fine, as i really want every dll to be copied and filter out pdb files.

The Problem arises, when creating the ServiceFiles.wxs file. I just can't figure out how to check wether an element exists in the first wxs file.

That link provided the information, that i could embed a C# function, to execute some logic. That seems like a neat trick to me, but still i don't know how to search the contents of the other file.

Current ServiceFilter.xslt

The ServiceFilter.xslt is nearly the same as the ConfiguratorFiles.xslt, but i also filter out .exe Files, as i handle them manually

  <!--Match and ignore .pdb files-->
  <xsl:key name="service-search" match="wix:Component[contains(wix:File/@Source, '.pdb')]" use="@Id" />
  <xsl:template match="wix:Component[key('service-search', @Id)]"/>
  <xsl:template match="wix:ComponentRef[key('service-search', @Id)]"/>

  <!--Match and ignore .exe files-->
  <xsl:key name="exe-search" match="wix:Component[contains(wix:File/@Source, '.exe')]" use="@Id"/>
  <xsl:template match="wix:Component[key('exe-search', @Id)]"/>
  <xsl:template match="wix:ComponentRef[key('exe-search', @Id)]"/>

Example:

I have the following component in both (ConfiguratorFiles.wxs and ServiceFiles.wxs). This results in an error, that is why i need to filter duplicates.

 <Component Id="Foo.Base.dll" Guid="*">
     <File Id="Foo.Base.dll" KeyPath="yes" Source="$(var.Foo.DSI.Configurator.TargetDir)\Foo.Base.dll" />
 </Component>

Actual Question

How to write a filter "ServiceFilter.xslt" that filters duplicates, so that ServiceFiles.wxs does not contain a file, that is contained in ConfiguratorFiles.wxs ?

Update

What i'm trying right now is to use a C# Method. Now i only need to figure out, how to get all Components in the first file to fill out the FindDuplicate method, as it currently filters everything :)

  <!--Match and ignore duplicate components-->
  <xsl:key name="duplicate-search" match="wix:Component[user:FindDuplicate(wix:File/@Source)]" use="@Id"/>
  <xsl:template match="wix:Component[key('duplicate-search', @Id)]"/>
  <xsl:template match="wix:ComponentRef[key('duplicate-search', @Id)]"/>
  <msxsl:script language="C#" implements-prefix="user">
    <![CDATA[  
     public bool FindDuplicate(string name){  
       return true;
     }  
      ]]>
  </msxsl:script>

Answer 1

The Solution was pretty easy.

I do now create 2 separate MSI-Files. One which installs the configurator and One installs the Service. These 2 MSI-Files are created in 2 different WiX projects, so the problem of duplicated entries won't appear anymore.