fix(CompiledRouter): support URI templates with a trailing slash

[vytas7]

Summary of Changes

Previously, the default CompiledRouter was erroneously stripping trailing slashes from URI templates.
This has been fixed so that it is now possible to add two different routes for a path with and without a trailing forward slash.

Related Issues

Closes #1544

Open Questions

I'm a bit divided what to do with add_route() in case RequestOptions.strip_url_path_trailing_slash is set to True, and the provided template ends with a trailing slash?

• Do nothing special, effectively adding a non-functional route that is never hit (this may be a breaking change is someone had such a route).
• Raise a ValueError asking to only add routes without a trailing slash (this may be a breaking change is someone had such a route).
• Strip the trailing slash from the template before submitting it to the router's add_route().
• Strip the trailing slash from the template before submitting it to the router's add_route(), and emit a deprecation warning.
• Something else?

I have now proceeded with the first option, documenting this as a breaking change, and sprinkling some warnings throughout the docs. Thanks @CaselIT for input!

[codecov]

Codecov Report

Merging #1751 into master will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master     #1751   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           52        52           
  Lines         4295      4295           
  Branches       690       690           
=========================================
  Hits          4295      4295           

Impacted Files	Coverage Δ
falcon/routing/compiled.py	100.00% <100.00%> (ø)

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[CaselIT]

Regarding the question, the problem I see is that we cannot assume that an user has set the options before adding the routes. Also the options may be dynamically updated.
Taking this into consideration, I don't think a warning should be raised, we should just document, maybe with a warning, the behaviour of the router wrt that request option.

[vytas7]

Ah, good point wrt the configuration order @CaselIT !
RequestOptions.strip_url_path_trailing_slash is by default False, so if the user hasn't set that to True yet, we obviously cannot do anything about it. But if the user has already overridden to True, I am inclined to emit a warning though, that might be helpful in debugging... 🤔

Edit: these routes with trailing slashes might actually be reachable with middleware path rewrite though... 🤔

[CaselIT]

The documentation looks good 👍

[kgriffs]

it is now possible to add two different routes for a path with and without a trailing forward slash

Is there a test for this specific use case? Otherwise LGTM. 👍

[vytas7]

@kgriffs good point; I have now added a dedicated test to better exercise this scenario.

[kgriffs]

LGTM