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 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.

[Source]

     # File lib/cgi/session.rb, line 371
371:       def initialize(session, option={})
372:         dir = option['tmpdir'] || Dir::tmpdir
373:         prefix = option['prefix'] || ''
374:         suffix = option['suffix'] || ''
375:         id = session.session_id
376:         require 'digest/md5'
377:         md5 = Digest::MD5.hexdigest(id)[0,16]
378:         @path = dir+"/"+prefix+md5+suffix
379:         if File::exist? @path
380:           @hash = nil
381:         else
382:           unless session.new_session
383:             raise CGI::Session::NoSession, "uninitialized session"
384:           end
385:           @hash = {}
386:         end
387:       end

Public Instance methods

close()

Update and close the session‘s FileStore file.

[Source]

     # File lib/cgi/session.rb, line 431
431:       def close
432:         update
433:       end
delete()

Close and delete the session‘s FileStore file.

[Source]

     # File lib/cgi/session.rb, line 436
436:       def delete
437:         File::unlink @path+".lock" rescue nil
438:         File::unlink @path+".new" rescue nil
439:         File::unlink @path
440:       rescue Errno::ENOENT
441:       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 392
392:       def restore
393:         unless @hash
394:           @hash = {}
395:           begin
396:             lockf = File.open(@path+".lock", "r")
397:             lockf.flock File::LOCK_SH
398:             f = File.open(@path, 'r')
399:             for line in f
400:               line.chomp!
401:               k, v = line.split('=',2)
402:               @hash[CGI::unescape(k)] = CGI::unescape(v)
403:             end
404:           ensure
405:             f.close unless f.nil?
406:             lockf.close if lockf
407:           end
408:         end
409:         @hash
410:       end
update()

Save session state to the session‘s FileStore file.

[Source]

     # File lib/cgi/session.rb, line 413
413:       def update
414:         return unless @hash
415:         begin
416:           lockf = File.open(@path+".lock", File::CREAT|File::RDWR, 0600)
417:           lockf.flock File::LOCK_EX
418:           f = File.open(@path+".new", File::CREAT|File::TRUNC|File::WRONLY, 0600)
419:           for k,v in @hash
420:             f.printf "%s=%s\n", CGI::escape(k), CGI::escape(String(v))
421:           end
422:           f.close
423:           File.rename @path+".new", @path
424:         ensure
425:           f.close if f and !f.closed?
426:           lockf.close if lockf
427:         end
428:       end

[Validate]