3 ms·

Is that so? RFC 3986 Appendix B [1] "Parsing a URI Reference with a Regular Expression": The following line is the regular expression for breaking-down a well

Is that so? RFC 3986 Appendix B [1] "Parsing a URI Reference with a Regular Expression": The following line is the regular expression for breaking-down a well-formed URI reference into its components. ^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))? scheme = $2 authority = $4 path = $5 query = $7 fragment = $9 Let's test your URI with this regex, shall we? [2] $2 (scheme) = http $4 (authority) = [f021:d981:b487:e57d:193e:550e::] $5 (path) = / Seems correct to me. [1] https://datatracker.ietf.org/doc/html/rfc3986#appendix-B https://datatracker.ietf.org/doc/html/rfc3986#appendix-B [2] https://regexr.com/8nqop https://regexr.com/8nqop

quuxplusone 2mo ago
Hm, but I think he's right. The problem comes when you try to break down the authority portion into host and port; TFA's parser treats the first colon as introducing the port, which is wrong. https://github.com/bkaradzic/bx/blob/0b001f5f36579e8aea07efa5af139ca18dad9505/src/url.cpp#L48-L123 https://github.com/bkaradzic/bx/blob/0b001f5f36579e8aea07efa...
- meindnoch 2mo ago
  >The problem comes when you try to break down the authority portion into host and port That's a problem orthogonal to URI parsing. You parse the URI with the RFC 3986 regex, which gives you the components: scheme, authority, path, query, fragment. You're then free to parse any of the components according to your own bespoke rules, e.g. the query string often follows the key=value&key=value&... pattern.
f311a 2mo ago
Regexes are pretty slow, though.
- meindnoch 2mo ago
  cc @burntsushi
afiori 2mo ago
> well-formed URI A parser that assumes the input to be already valid is usually not enough for most applications according to that regex this is a valid url __..__..%%%zz..
- meindnoch 2mo ago
  >according to that regex this is a valid url >__..__..%%%zz.. Correctly. It is a valid relative URI, whose path is "__..__..%%%zz..".
  - afiori 1mo ago
    % characters must be escaped in URIs at the very least, and _ is not valid in domains also this one is valid too for the regex %_%://%_%.%_%/%_%?%_%#%_%
    - afiori 1mo ago
      courtesy of chatgpt there is also this abomination ht tp://[\x00::gg]\t/foo\nbar/%/%QZ/%F?q=<\"|{}>##

quuxplusone 2mo ago

Hm, but I think he's right. The problem comes when you try to break down the authority portion into host and port; TFA's parser treats the first colon as introducing the port, which is wrong. https://github.com/bkaradzic/bx/blob/0b001f5f36579e8aea07efa5af139ca18dad9505/src/url.cpp#L48-L123 https://github.com/bkaradzic/bx/blob/0b001f5f36579e8aea07efa...

meindnoch 2mo ago
>The problem comes when you try to break down the authority portion into host and port That's a problem orthogonal to URI parsing. You parse the URI with the RFC 3986 regex, which gives you the components: scheme, authority, path, query, fragment. You're then free to parse any of the components according to your own bespoke rules, e.g. the query string often follows the key=value&key=value&... pattern.

f311a 2mo ago

Regexes are pretty slow, though.

meindnoch 2mo ago
cc @burntsushi

afiori 2mo ago

> well-formed URI A parser that assumes the input to be already valid is usually not enough for most applications according to that regex this is a valid url __..__..%%%zz..

meindnoch 2mo ago
>according to that regex this is a valid url >__..__..%%%zz.. Correctly. It is a valid relative URI, whose path is "__..__..%%%zz..".
- afiori 1mo ago
  % characters must be escaped in URIs at the very least, and _ is not valid in domains also this one is valid too for the regex %_%://%_%.%_%/%_%?%_%#%_%
  - afiori 1mo ago
    courtesy of chatgpt there is also this abomination ht tp://[\x00::gg]\t/foo\nbar/%/%QZ/%F?q=<\"|{}>##