Universal-Link-Validator

A simple node app for testing your Apple App Site Association file setup.

Check out the example instance running on Heroku.

Why?

Apple previously did not (they do now) provide any tool to validate your domain, similiar to the Facebook Debugger that I find super helpful, so the whole process becomes a complete black box to the end user. If you check device logs, you can see some messages about the failure when you install the app, but they're not really helpful in any way.

I decided to take a bit of time to put this together as a quick and easy way to quickly validate a domain (or an IPA file, checking the Info.plist) against some of the requirements I've been able to find across Apple's various documentation sources around this feature.

Sources

Shared Web Credentials provides the majority of requirements .

• The exact format of the constructed url is https://domain[:port]/apple-app-site-association.
• The file must be hosted on an https:// site with a valid certificate.
• The file must not use any redirects.
• The file must have the MIME type application/pkcs7-mime.
• The file must be CMS signed by a valid TLS certificate.

App Search Programming provides the expected format for UL specifically.