I forget if it's the key path or not, but it uses the SHA checksum of a string based on a namespace GUID and the seed value.. Key path as the seed is very logical in that regards.
> On Mar 29, 2015, at 9:35 AM, John Cooper <jocoo...@jackhenry.com> wrote: > > I believe it uses an algorithm to generate the GUID based on the KeyPath, but > that's just from memory. > > -- > John Merryweather Cooper > Senior Software Engineer | Integration Development Group | Continuing > Development > Jack Henry & Associates, Inc.® | Lenexa, KS 66214 | Ext: 431050 > |jocoo...@jackhenry.com > > > > -----Original Message----- > From: Pat Blair [mailto:p...@daburu.net] > Sent: Sunday, March 29, 2015 9:12 AM > To: wix-users@lists.sourceforge.net > Subject: [WiX-users] How does heat maintain consistent GUIDs? > > I am curious to know how WiX keeps track of GUIDSs automatically generated > for files when we use HeatDirectory. > > For example, I have a project with the following in my .wixproj file... > > <Target Name="BeforeBuild"> > <PropertyGroup> > <WixToolPath>C:\SourceControl\WiX39\</WixToolPath> > </PropertyGroup> > <HeatDirectory ToolPath="$(WixToolPath)" > Directory="C:\users\me\Desktop\SourceFiles > > ComponentGroupName="MyComponentGroup" > DirectoryRefId="INSTALLFOLDER" > AutogenerateGuids="true" > GenerateGuidsNow="false" > SuppressFragments="true" > SuppressRootDirectory="true" > PreprocessorVariable="var.SourceFilesDir" > OutputFile="Components.wxs" /> > </Target> > > If I set AutogenerateGuids="true", my output file contains components like > this: > > <Component Id="cmpA609F30B9E3AECCDEE4D779C8B7308ED" Guid="*"> > <File Id="fil314398091041DF4762128892E7C98AA7" > KeyPath="yes" Source="$(var.SourceFilesDir)\Sample1.txt" /> > </Component> > > I note that Component/@Guid="*". > > After generating the .MSI, I open it with Orca and see that the ComponentId > for each Component (for each file) is the same. > > If I change my HeatDirectory element so that AutogenerateGuids="false" and > GenerateGuidsNow="true", the ComponentIds seem to change. > > If I understand correctly, this is how it should work and by using > AutogenerateGuids, my installers can track a given file from install to > install. I also think I understand that the GUIDs will remain the same so > long as the file names and paths to which they are installed doesn't change, > so this approach will let me do minor upgrades because the installers can > tell that two versions of a file from two different installers are the same > component because the ComponentIDs match. > > But what I'm wondering is: How are these consistent GUIDs that I get when I > use AutogenerateGuids="true" remembered from build to build? Are they > generated by some algorithm that will always produce the same GUID for a file > with a given name installed to a given directory, or are they stored > somewhere. And if they are stored somewhere, where are they stored? > > I'm hoping this isn't a dumb question, but I feel like I need to understand > this before using the feature so I don't make mistakes based on an incomplete > comprehension of what's happening behind-the-scenes. > > Many thanks. > ------------------------------------------------------------------------------ > Dive into the World of Parallel Programming The Go Parallel Website, > sponsored by Intel and developed in partnership with Slashdot Media, is your > hub for all things parallel software development, from weekly thought > leadership blogs to news, videos, case studies, tutorials and more. Take a > look and join the conversation now. http://goparallel.sourceforge.net/ > _______________________________________________ > WiX-users mailing list > WiX-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/wix-users > NOTICE: This electronic mail message and any files transmitted with it are > intended > exclusively for the individual or entity to which it is addressed. The > message, > together with any attachment, may contain confidential and/or privileged > information. > Any unauthorized review, use, printing, saving, copying, disclosure or > distribution > is strictly prohibited. If you have received this message in error, please > immediately advise the sender by reply email and delete all copies. > > > ------------------------------------------------------------------------------ > Dive into the World of Parallel Programming The Go Parallel Website, sponsored > by Intel and developed in partnership with Slashdot Media, is your hub for all > things parallel software development, from weekly thought leadership blogs to > news, videos, case studies, tutorials and more. Take a look and join the > conversation now. http://goparallel.sourceforge.net/ > _______________________________________________ > WiX-users mailing list > WiX-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/wix-users ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ WiX-users mailing list WiX-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wix-users
