Bug #17029: URI.parse considers https://example.com/### invalid when browsers consider it valid

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 2.7.1p83 (2020-03-31 revision a0c7c23c9c) [x86_64-darwin19]
• Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN

[nileshtr (Nilesh Trivedi)]

I have a form with <input type="url" required> and in the backend, I try to extract the domain with URI.parse(url).host

A user was able to submit a value like https://example.com/### which passed the browser's validation check, but failed by URI.parse with this error:

        3: from /Users/helix/.rbenv/versions/2.7.1/lib/ruby/2.7.0/uri/common.rb:234:in `parse'
        2: from /Users/helix/.rbenv/versions/2.7.1/lib/ruby/2.7.0/uri/rfc3986_parser.rb:73:in `parse'
        1: from /Users/helix/.rbenv/versions/2.7.1/lib/ruby/2.7.0/uri/rfc3986_parser.rb:67:in `split'
URI::InvalidURIError (bad URI(is not URI?): "https://example.com/###")

You can try the browser's behavior at MDN's demo: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input/url

This is what the MDN page says about validation:

The syntax of a URL is fairly intricate. It's defined by WHATWG's URL Living Standard ( https://url.spec.whatwg.org/ ) and is described for newcomers in our article What is a URL? ( https://developer.mozilla.org/en-US/docs/Learn/Common_questions/What_is_a_URL )

[jeremyevans0 (Jeremy Evans)]

This does seem like a bug to me. It looks like https://example.com/### should be an valid URL with a fragment of ##. However, the uri library is maintained in a separate repository. Please submit this as an issue to https://github.com/ruby/uri/issues/new.

[phluid61 (Matthew Kerwin)]

It's not valid according to RFC 3986 (the URI standard) but that is pretty old now. I suspect switching from the IETF URI spec to the WHATWG URL spec would have other consequences, too.

[nileshtr (Nilesh Trivedi)]

I filed an issue at the uri library's Github repo: https://github.com/ruby/uri/issues/8

[jeremyevans0 (Jeremy Evans)]

• Status changed from Open to Closed