Re: [hybi] WebSocket sub protocol name.

[Mark Nottingham <[e-mail]>]

On 07/12/2009, at 7:05 PM, Ian Hickson wrote:

>> And, why is it limited to ASCII instead of UTF-8?
> 
> Because the HTTP working group refuse to allow UTF-8 in HTTP headers for 
> reasons that I don't really understand, and the handshake is supposed to 
> be valid HTTP.


From <http://tools.ietf.org/html/draft-ietf-httpbis-p1-messaging-08#section-3.2>:

   Historically, HTTP has allowed field content with text in the ISO-
   8859-1 [ISO-8859-1] character encoding and supported other character
   sets only through use of [RFC2047] encoding.  In practice, most HTTP
   header field values use only a subset of the US-ASCII character
   encoding [USASCII].  Newly defined header fields SHOULD limit their
   field values to US-ASCII characters.  Recipients SHOULD treat other
   (obs-text) octets in field content as opaque data.

If you really want to define a UTF-8 HTTP header, you're allowed to do so by this text (which makes ASCII only a SHOULD); processors not expecting it SHOULD still treat it as if it were opaque data.


--
Mark Nottingham     http://www.mnot.net/