Reference a heat generated wxs file from a merge module - wix

Question

I want to create a trivial merge module that contains all the files of a directory called "build" and installs them to the program files folder. I will use heat to generate a wxs file with all these files, and I want this to be separated from the wxs file I edit manually for the merge module. How do I reference the heat generated file from my other merge module wxs file?
I generate my heat wxs file like this:
heat dir build -cg heatComponent -gg -var var.buildFolder -dr ProgramFilesFolder -srd -out heatComponent.wxs
I know how to create an msi file of this:
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
<Product Name='product' Id='9f6edf70-539a-11e4-916c-0800200c9a66' UpgradeCode='bb651370-539a-11e4-916c-0800200c9a66'
Language='1033' Codepage='1252' Version='1.0.0' Manufacturer='Test'>
<Package Id='*' Description="A product" InstallerVersion='301' Languages='1033' Compressed='yes' SummaryCodepage='1252' Platform='x64'/>
<Media Id="1" Cabinet="product.cab" EmbedCab="yes" />
<Directory Id='TARGETDIR' Name='SourceDir'>
<Directory Id='ProgramFilesFolder'/>
</Directory>
<Feature Id="Files" Title="Main Feature" Level="1">
<ComponentGroupRef Id="heatComponent"/>
</Feature>
</Product>
</Wix>
But how do I do reference the ComponentGroup when I want to output a merge module? If I change the Product element to a Module element it complaints about the Feature element. If I remove that it works, but I do not get any files in my msm.

Answer 1

Based on the heat command you posted, try making your module definition (module1.wxs) look something like this:
<?xml version="1.0" encoding="utf-8"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
<Module Id="Mod1" Language="0" Version="1.0.0">
<Package Id="YOUR-GUID" Manufacturer="Acme" />
<Directory Id="TARGETDIR" Name="SourceDir">
<Directory Id="ProgramFilesFolder" />
</Directory>
<ComponentGroupRef Id="heatComponent"/>
</Module>
</Wix>
Then you can call candle like so:
candle module1.wxs heatComponent.wxs -dbuildFolder="FOLDER-CONTAINING-FILES-HERE"
Followed by light like so:
light module.wixobj heatComponent.wixobj -o Module1.msm