Class: CGI::Session::FileStore

Inherits:

Object

• Object
• CGI::Session::FileStore

Defined in:

lib/cgi/session.rb

Overview

File-based session storage class.

Implements session storage as a flat file of ‘key=value’ values. This storage type only works directly with String values; the user is responsible for converting other types to Strings when storing and from Strings when retrieving.

Instance Method Summary

• #close ⇒ Object

  Update and close the session’s FileStore file.

• #delete ⇒ Object

  Close and delete the session’s FileStore file.

• #initialize(session, option = {}) ⇒ FileStore constructor

  Create a new FileStore instance.

• #restore ⇒ Object

  Restore session state from the session’s FileStore file.

• #update ⇒ Object

  Save session state to the session’s FileStore file.

Constructor Details

#initialize(session, option = {}) ⇒ FileStore

Create a new FileStore 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 initialiser. The following options are recognised:

tmpdir

the directory to use for storing the FileStore 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 FileStore file. Defaults to the empty string.

suffix

the prefix to add to the session id when generating the filename for this session’s FileStore file. Defaults to the empty string.

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

# File 'lib/cgi/session.rb', line 369

def initialize(session, option={})
	dir = option['tmpdir'] || Dir::tmpdir
	prefix = option['prefix'] || ''
	suffix = option['suffix'] || ''
	id = session.session_id
  require 'digest/md5'
  md5 = Digest::MD5.hexdigest(id)[0,16]
	@path = dir+"/"+prefix+md5+suffix
	if File::exist? @path
	  @hash = nil
	else
    unless session.new_session
      raise CGI::Session::NoSession, "uninitialized session"
    end
	  @hash = {}
	end
end

Instance Method Details

#close ⇒ Object

Update and close the session’s FileStore file.

# File 'lib/cgi/session.rb', line 423

def close
	update
end

#delete ⇒ Object

Close and delete the session’s FileStore file.

# File 'lib/cgi/session.rb', line 428

def delete
  File::unlink @path
rescue Errno::ENOENT
end

#restore ⇒ Object

Restore session state from the session’s FileStore file.

Returns the session state as a hash.

# File 'lib/cgi/session.rb', line 390

def restore
	unless @hash
	  @hash = {}
    begin
	    f = File.open(@path, 'r')
	    f.flock File::LOCK_SH
	    for line in f
 line.chomp!
 k, v = line.split('=',2)
 @hash[CGI::unescape(k)] = CGI::unescape(v)
	    end
    ensure
	    f.close unless f.nil?
    end
	end
	@hash
end

#update ⇒ Object

Save session state to the session’s FileStore file.

# File 'lib/cgi/session.rb', line 409

def update
	return unless @hash
  begin
	  f = File.open(@path, File::CREAT|File::TRUNC|File::RDWR, 0600)
	  f.flock File::LOCK_EX
for k,v in @hash
	    f.printf "%s=%s\n", CGI::escape(k), CGI::escape(String(v))
	  end
  ensure
    f.close unless f.nil?
  end
end