Redirect URI strategies for desktop applications?

[DaveCa]

I'm looking to write a desktop application. I'd rather not require certain ports be open for my app to receive the auth code via the redirect URI. 

Given this, and given there does not seem to be an option to wild-card ports when registering redirect URIs on the Spotify dashboard: what do other people do? Do you register many, many different localhost URIs, each one with a different port number? Do you register a custom protocol handler in the OS (in a similar manner as the Spotify desktop client)? Something else entirely? 

[DaveCa]

FWIW I'm going with the "many redirect URLs" approach - https://svn.nmap.org/nmap/nmap-services shows thousands of TCP ports that are apparently never used (hello AppleTalk 😉 ). I'm picking 5-10 ports & guessing that there are no computers out there with all 5-10 in use. 

Technically I'm not supposed to make use of ports registered with IANA, but this is on a client's local computer (so not many services running), and the port won't be open very long.