Installer

Installer just installs WixUI whose job is to:

Run the client code to unpack the latest full NuGet package and finish initial install.
Execute the uninstaller code when WiX goes to remove us, and remove the App directory.

So, on install:

WiX unpacks WixUI and runs it, and puts an entry in Programs and Features.
WixUI executes initial install using Squirrel.Client for the full NuGet package, doing the update in-place so the installer never needs to be rebuilt.

On Uninstall:

WiX gets notified about the uninstall, calls WixUI to do app uninstall via Squirrel.Client
WiX then blows away WixUI, the "real" installed app.

Bootstrap UI

WixUI has an extremely simple UI when it does its work, it just pops up, shows a progress bar, a-la Chrome Installer:

On Uninstall, there is no UI, it's solely in the background.

If Setup.exe gets invoked with the 'Install' action, and the app is already installed, we just execute the app, a-la ClickOnce.

Generating the WiX installer

The WiX install script is generated via a Mustache template, whose contents are primarily populated via the generated NuGet release package. WiX will end up installing WixUI, the latest NuGet package file, and a one-line RELEASES file (meaning that what WiX installs is technically a valid Squirrel remote update directory).

WiX Engine Events and what we should do about them

DetectedPackage - if we're installed (determine this by looking at the NuGet package in the same directory as the app), we run the app and bail.
DetectComplete - Do what we're actually here to do (invoke the Squirrel installer), then on the UI thread, tell WiX to finish up.
PlanPackageBegin - squelch installation of .NET 4
PlanComplete - Push WiX to to Apply state
ApplyComplete - If something bad happened, switch to UI Error state, otherwise start the app if we're in Interactive Mode and call Shutdown()
ExecuteError - Switch to the UI Error state

2.1 KiB Raw Blame History