class CGI::Session::PStore

PStore-based session storage class.

This builds upon the top-level PStore class provided by the library file pstore.rb. Session data is marshalled and stored in a file. File locking and transaction services are provided.

Public Class Methods

new(session, option={}) click to toggle source

Create a new CGI::Session::PStore instance

This constructor is used internally by CGI::Session. The user does not generally need to call it directly.

session is the session for which this instance is being created. The session id must only contain alphanumeric characters; automatically generated session ids observe this requirement.

option is a hash of options for the initializer. The following options are recognised:

tmpdir: the directory to use for storing the PStore file. Defaults to Dir::tmpdir (generally “/tmp” on Unix systems).
prefix: the prefix to add to the session id when generating the filename for this session's PStore file. Defaults to the empty string.

This session's PStore file will be created if it does not exist, or opened if it does.

# File lib/cgi/session/pstore.rb, line 46
def initialize(session, option={})
  dir = option['tmpdir'] || Dir::tmpdir
  prefix = option['prefix'] || ''
  id = session.session_id
  require 'digest/md5'
  md5 = Digest::MD5.hexdigest(id)[0,16]
  path = dir+"/"+prefix+md5
  path.untaint
  if File::exist?(path)
    @hash = nil
  else
    unless session.new_session
      raise CGI::Session::NoSession, "uninitialized session"
    end
    @hash = {}
  end
  @p = ::PStore.new(path)
  @p.transaction do |p|
    File.chmod(0600, p.path)
  end
end

Public Instance Methods

close() click to toggle source

Update and close the session's PStore file.

# File lib/cgi/session/pstore.rb, line 88
def close
  update
end

delete() click to toggle source

Close and delete the session's PStore file.

# File lib/cgi/session/pstore.rb, line 93
def delete
  path = @p.path
  File::unlink path
end

restore() click to toggle source

Restore session state from the session's PStore file.

Returns the session state as a hash.

# File lib/cgi/session/pstore.rb, line 71
def restore
  unless @hash
    @p.transaction do
      @hash = @p['hash'] || {}
    end
  end
  @hash
end

update() click to toggle source

Save session state to the session's PStore file.

# File lib/cgi/session/pstore.rb, line 81
def update
  @p.transaction do
    @p['hash'] = @hash
  end
end