Incompatibility with Rails 5.2 ActiveStorage

[CodingAnarchy]

ActiveStorage uses signed_blob_id parameters that are case-sensitive. At present, this is incompatible with the route_downcaser gem. However, the downcasing of routes in general is a useful concept. If there would be any way to exempt these ActiveStorage generated urls (they are typically of the form /rails/active_storage/... with the built-in routing in Rails), that would really help me out.

[koppen]

Uh, that sucks, thanks for reporting. I wonder if it'd be possible to configure your way out of this?

Something like

  config.exclude_patterns = [
    /rails\/active_storage\//i,
  ]

should prevent route_downcaser from modifying URLs in the /rails/active_storage/ paths.

[lostapathy]

I just spent quite a while trying to track down this same issue myself. The example by @koppen does indeed work around the issue. Is there any strong reason we couldn't make that the default and save others the trouble of discovering it?

FWIW, I took a go at ActiveStorage about a year ago and gave up thinking it was broken at the time. I was quite surprised this was the fix! I'm not trying to place blame at all, but I think there's a strong argument for making route_downcaser work with ActiveStorage out of the box.

[koppen]

Cool, thanks for verifying the fix @lostapathy.

route_downcaser tries to assume as little as possible about your environment or application as possible, and it's not a Rails-only gem, so adding exceptions for Rails-specific functionality or other third party behaviour seems out of scope.

If we do want to add something, it should probably be some opt-in thing, perhaps a configuration option (config.active_storage = true) or the like?

That said, at the very least we should be able to document it, perhaps as a special note in the section about exclude_patterns. I'll be happy to look at any pull requests with improvements for this.