On 10 Dec 2009, at 22:30, Eric Wong wrote:

> Hi all,
> 
> I've been notified privately that my changes for PATH_INFO in Unicorn
> 0.95.2 (which also got into Thin) may not be completely kosher, but I'm
> also asking for the Rack team to clarify PATH_INFO for HTTP parser
> implementers.
> 
> 
> Upon further reading (and also of the
> related-but-not-necessarily-true-for-Rack RFC 3875 section 4.1.5),
> I came across this:
> 
>   Unlike a URI path, the PATH_INFO is not URL-encoded, and cannot
>   contain path-segment parameters.
> 
> First off, Rack already directly contradicts the "the PATH_INFO is not
> URL-encoded" part, so Unicorn conforms to Rack specs over RFC 3875.
> 
> *But* Rack does not address the "cannot contain path-segment parameters"
> part at all.  So I (and probably a few other people) would like
> clarification on how to handle PATH_INFO when it comes to ";"
> 
> 
> Things to keep in mind:
> 
>  * URI.parse keeps ";" in URI::HTTP#path
>    This point may not be relevant to us, as PATH_INFO and
>    URI::HTTP#path should not necessarily be treated as equals
> 
>  * WEBrick keeps ";" in PATH_INFO
> 
>  * PEP333 (which Rack is based on) does not go into this level of
>    detail regarding PATH_INFO and path segments
> 
>  * PATH_INFO in Rack appears to be based on CGI/1.1 (RFC 3875)
> 
>  * Again, Rack already contradicts the URL encoding rules of RFC 3875
>    for PATH_INFO, so there is precedence for Rack contradicting more
>    of RFC 3875...
> 
>  * Rack::Request#full_path only looks at PATH_INFO + QUERY_STRING,
>    this means many Rack applications may never see the ";" parts
>    if Thin and Unicorn revert to old behavior.
> 
>  * Rack does not require REQUEST_URI, this is an extension Unicorn
>    and Thin both carried over from Mongrel.
> 
>  * None of the official rack/rack-contrib middleware use REQUEST_URI

* http://twistedmatrix.com/trac/ticket/1361

* http://jira.codehaus.org/browse/JETTY-980 (although not directly relevant, may be food for thought)

* http://ksi.cpsc.ucalgary.ca/archives/WWW-TALK/www-talk-1994q1.messages/3.html (ancient history)

* http://code.google.com/p/googleappengine/issues/detail?id=1340

> Of course, in the grand scheme of things, hardly anybody uses ";" in
> paths.  Yay for rare corner cases making our lives difficult.

Amen, because I feel like I want to say "be configurable", given all of the above.

> 
> -- 
> Eric Wong