Class CGI::Session::FileStore
In: lib/cgi/session.rb
Parent: Object

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.

Methods

close   delete   new   restore   update  

Public Class methods

new(session, option={})

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 initializer. 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.

[Source]

     # File lib/cgi/session.rb, line 377
377:       def initialize(session, option={})
378:         dir = option['tmpdir'] || Dir::tmpdir
379:         prefix = option['prefix'] || ''
380:         suffix = option['suffix'] || ''
381:         id = session.session_id
382:         require 'digest/md5'
383:         md5 = Digest::MD5.hexdigest(id)[0,16]
384:         @path = dir+"/"+prefix+md5+suffix
385:         if File::exist? @path
386:           @hash = nil
387:         else
388:           unless session.new_session
389:             raise CGI::Session::NoSession, "uninitialized session"
390:           end
391:           @hash = {}
392:         end
393:       end

Public Instance methods

close()

Update and close the session‘s FileStore file.

[Source]

     # File lib/cgi/session.rb, line 437
437:       def close
438:         update
439:       end
delete()

Close and delete the session‘s FileStore file.

[Source]

     # File lib/cgi/session.rb, line 442
442:       def delete
443:         File::unlink @path+".lock" rescue nil
444:         File::unlink @path+".new" rescue nil
445:         File::unlink @path
446:       rescue Errno::ENOENT
447:       end
restore()

Restore session state from the session‘s FileStore file.

Returns the session state as a hash.

[Source]

     # File lib/cgi/session.rb, line 398
398:       def restore
399:         unless @hash
400:           @hash = {}
401:           begin
402:             lockf = File.open(@path+".lock", "r")
403:             lockf.flock File::LOCK_SH
404:             f = File.open(@path, 'r')
405:             for line in f
406:               line.chomp!
407:               k, v = line.split('=',2)
408:               @hash[CGI::unescape(k)] = CGI::unescape(v)
409:             end
410:           ensure
411:             f.close unless f.nil?
412:             lockf.close if lockf
413:           end
414:         end
415:         @hash
416:       end
update()

Save session state to the session‘s FileStore file.

[Source]

     # File lib/cgi/session.rb, line 419
419:       def update
420:         return unless @hash
421:         begin
422:           lockf = File.open(@path+".lock", File::CREAT|File::RDWR, 0600)
423:           lockf.flock File::LOCK_EX
424:           f = File.open(@path+".new", File::CREAT|File::TRUNC|File::WRONLY, 0600)
425:           for k,v in @hash
426:             f.printf "%s=%s\n", CGI::escape(k), CGI::escape(String(v))
427:           end
428:           f.close
429:           File.rename @path+".new", @path
430:         ensure
431:           f.close if f and !f.closed?
432:           lockf.close if lockf
433:         end
434:       end

[Validate]