Add URL Scheme parser and test

[ryanbooker]

💬 Summary of Changes

• Implements a scheme parser to support routing older style custom schemes on iOS.

✅ Checklist

• 🧐 Performed a self-review of the changes.
• ✅ Added tests to cover changes.
• 🏎 Ran Unit Tests before opening PR.

[stephencelis]

@ryanbooker Thanks for taking the time to PR! There was a similar one opened here before we extracted the library that was closed in favor of the baseURL and baseRequestData methods. Curious if you agree with this or if you have some example uses of where parsing the scheme can be useful?

I think generally the most important parsers are the ones that can change throughout a single server process, and that nginx/Apache are kind of responsible for the server-level things, like scheme, host, etc.

[robfeldmann]

Curious if you agree with this or if you have some example uses of where parsing the scheme can be useful?

I've been thinking about this too. I think being able to parse any part of the URL components is useful. For example, I have a need to parse/match the fragment of a URL for deep linking purposes, so I'm working on a Fragment ParserPrinter (although it's taking me an embarrassing amount of time to get it right).

I would also like to add a Host parser for the same reason. I can see needing to be able match on a custom scheme as well, even if it isn't suitable or recommended for printing/routing.

[ryanbooker]

Thanks for the response @stephencelis. I'm not sure I quite follow, and I've only been using the Library for "5 min" so if there's another way to do what I want, please point me at it! 😄

I want to parse a specific custom scheme on the app side (ignoring the fact that Apple discourages using them nowadays).

I'm working with some legacy code where the schemes can't be changed at the moment, and there are several custom schemes that have been used as routes. So rather than customScheme://route1, customScheme://route2, I have route1:// and route2://.

I want to parse a specific scheme and the parser should fail if the scheme doesn't match…

I can keep the Scheme parser in my local code, but thought it may be useful for others. But if there's a better way to do what I'd like, please let me know. 😅

UPDATE: Turns out I misread the current code, and there is only one Scheme, however all the routes are based on the Host rather than a Path. e.g.customerSceheme://route1 and customScheme://route2. I can add a similar Host parser if you decide either of these are useful/nice to have. 🙂

[stephencelis]

UPDATE: Turns out I misread the current code, and there is only one Scheme, however all the routes are based on the Host rather than a Path. e.g.customerSceheme://route1 and customScheme://route2. I can add a similar Host parser if you decide either of these are useful/nice to have. 🙂

Typically if you want a path you would use customScheme:///route1, etc., but I can see that if it's out of your control a host parser could be useful...I think the thing we want to figure out is accidental misuse, e.g., if you use Host(…) or Scheme(…) because you want them to print in your routes, baseURL is often more appropriate, but docs can probably steer people the right direction.

Because of this, I think we'll take this after all! If you create a Host parser, please do submit a PR for it!

[ryanbooker]

Cool. No worries. I'll make a Host version as well. Thanks. :) customScheme:///route1 makes sense, but the urls aren't really under my control, at least in the short term. Cheers. :)