Add download-url-suffix to generate_appcast

[brzzdev]

Summary

For debug builds of our app, they're behind our internal GitLab instance and require a private_key. The feedParameters of SPUUpdaterDelegate works wonderfully for grabbing the XML itself, but then the DMG fails to download.

Right now, I have to edit the XML after creation to append ?private_key=exampleKey to the URL. Having a built-in option to match the download-url-prefix would be amazing.

Version

All

[zorgiepoo]

Custom HTTP headers are passed to the appcast & download. I think auth tokens and such normally use headers, not feed parameters. Adding parameters on the URL for this seems odd.

[brzzdev]

Yeah, turns out I was using feedParameters when I should have been using willDownloadUpdate item with request. I didn't realise the latter existed until your answer pointed me in the right direction.

[zorgiepoo]

I actually forgot about that delegate method, that would work. Though I think having private key in the feed parameters is still odd.