From: "Ara.T.Howard" <ahoward@...>
Date: 2003-12-19T06:21:57+09:00
Subject: Re: CGI::Session on mod_ruby

On Fri, 19 Dec 2003, John Long wrote:

> Date: Fri, 19 Dec 2003 02:43:38 +0900
> From: John Long <ng@johnwlong.com>
> Newsgroups: comp.lang.ruby
> Subject: CGI::Session on mod_ruby
> 
> The following script is a simple page counter that works well for me running
> as an rhtml file on mod_ruby:
> 
> <%
> require 'cgi/session'
> 
> cgi = CGI.new('html4')
> 
> session = CGI::Session.new(cgi)
> 
> session['count'] ||= 0
> session['count'] = session['count'].to_i + 1
> 
> # content must be output in this way in order for headers to be written:
> cgi.out { "count: " + session['count'] }
> 
> session.close
> %>
> 
> However, if I replace the line "cgi.out ..." with "puts session['count']"
> the script fails incrediment indicating that a new session is being created
> every time. I would assume this is because the right headers (cookies,
> etc...) are not written out in the response. If you use CGI::Session are you
> forced to use cgi.out rather than your own output method?

from cgi/session.rb
....
# Most session state is maintained on the server.  However, a session
# id must be passed backwards and forwards between client and server
# to maintain a reference to this session state.
#
# The simplest way to do this is via cookies.  The CGI::Session class
# provides transparent support for session id communication via cookies
# if the client has cookies enabled.
# 
# If the client has cookies disabled, the session id must be included
# as a parameter of all requests sent by the client to the server.  The
# CGI::Session class in conjunction with the CGI class will transparently
# add the session id as a hidden input field to all forms generated
# using the CGI#form() HTML generation method.  No built-in support is
# provided for other mechanisms, such as URL re-writing.  The caller is
# responsible for extracting the session id from the session_id 
# attribute and manually encoding it in URLs and adding it as a hidden
# input to HTML forms created by other mechanisms.  Also, session expiry
# is not automatically handled.
....

that being said, you can always simply:

require 'cgi'
require 'cgi/session'
cgi = CGI.new 
session = CGI::Session.new(cgi = CGI.new)
c = (session['count'] ||= 0)
printf "%s\ncount: %s\n", cgi.header, c
session['count'] = session['count'].succ
session.close


this is all CGI#out really does anyhow.


-a
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