From: ahoward <ahoward@...>
Date: 2002-11-09T01:53:22+09:00
Subject: Re: CGI::Session::FileStore question

On Thu, 7 Nov 2002, Yukihiro Matsumoto wrote:

[snip]
> It is not too hard to define something like CGI::Session::PStore.
> Sufficient for your homework.

i think this is not _directly_ possible because of []= in CGI::Session we have

  def []=(key, val)
    unless @write_lock
      @write_lock = true
    end
    unless @data
      @data = @dbman.restore
    end
    @data[key] = String(val)	# <--- problem here?
  end

seems like this should only be

  @data[key] = val

and left to the individual dbman to stringify, or not.  i did create a working
PStoreStore by making this change (baby unit test included) but i thought one
should not have to change CGI::Session


  require 'cgi/session'
  require 'pstore'

  class CGI
    class Session
      def []=(key, val)
	unless @write_lock
	  @write_lock = true
	end
	unless @data
	  @data = @dbman.restore
	end
	#@data[key] = String(val)
	@data[key] = val
      end

      class PStoreStore
	def check_id(id)
	  /[^0-9a-zA-Z]/ =~ id.to_s ? false : true
	end

	def initialize session, option={}
	  dir = option['tmpdir'] || ENV['TMP'] || '/tmp'
	  prefix = option['prefix'] || ''
	  id = session.session_id
	  unless check_id(id)
	    raise ArgumentError, "session_id `%s' is invalid" % id
	  end
	  path = dir+"/"+prefix+id
	  path.untaint
	  unless File::exist? path
	    @hash = {}
	  end
	  @p = PStore.new path
	end

	def restore
	  unless @hash
	    @p.transaction do
	      begin
		@hash = @p['hash']
	      rescue
		@hash = {}
	      end
	    end
	  end
	  @hash
	end

	def update
	  @p.transaction do
	      @p['hash'] = @hash
	  end
	end

	def close
	  update
	end

	def delete
	  path = @p.path
	  File::unlink path
	end

      end
    end
  end


if $0 == __FILE__
  require 'cgi'
  $stdin = open '|echo'
  cgi = CGI.new
  $stdin = STDIN
  session = CGI::Session.new cgi, 'database_manager' => CGI::Session::PStoreStore
  session['key'] = {'k' => 'v'}
  puts session['key'].type
  fail unless Hash === session['key']
  puts session['key'].inspect
  fail unless session['key'].inspect == '{"k"=>"v"}'
end



-ara

-- 

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 | Ara Howard
 | NOAA Forecast Systems Laboratory
 | Information and Technology Services
 | Data Systems Group
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 | Email: ahoward@fsl.noaa.gov
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