Class variables and servers

Rails
1

In my local development environment I define a class variabel
@@has:flock? in a modele that is included in controllers so I can
reset this variable in each controller that has to change it
The code in the module is
module CrudActions
@@page_records=15
@@has_flock = true

def index
if @@has_flock : paginate_conditions=[‘flock_id=?
‘,current_user.flock.id]
else paginate_conditions=’’ end

…and in the controller
class DiswebUsersController < ApplicationController
include CrudActions
@@page_records=15
…

That works fine locally but when I deploy the application and use an
apache server it does not work anymore (@@has_flock? is false) in the
method index
Then the variable is not set in the module
Any idees of what is happening ?
I can fix it by defining a method, but I wauld like to know if that is
necessery
Any help is appreciate?

2

Hi Hans,

processes don’t know each other and i.g. you can’t control which
instance of
your Application responds to the next request, this means:

Apache (T=0)
|

  • < Application (Process 0)
    | @@flock = nil
    |
    |

  • Fork’d Application (Process 1)
    | @@flock = nil
    |

  • Fork’d Application (Process 2)
    @@flock = nil

Apache (T=1)
|

  • < Application (Process 0)
    | @@flock = nil
    |
    |

  • Fork’d Application (Process 1)
    | @@flock = nil
    |

  • Fork’d Application (Process 2) < - REQUEST 1 200
    @@flock = nil

Apache (T=2)
|

  • < Application (Process 0)
    | @@flock = nil
    |
    |

  • Fork’d Application (Process 1) < - REQUEST 2 500
    | @@flock = nil
    |

  • Fork’d Application (Process 2)
    @@flock = true

If you use Mongrel or Thin whereas only a single Process for your
application
exists the class variable is always the same.

Thin (T=0, Process 0)
|

  • <> Application
    @@flock = nil

Thin (T=1, Process 0)
|

  • <> Application < - REQUEST 1 200
    @@flock = nil

Thin (T=2, Process 0)
|

  • <> Application < - REQUEST 2 200
    @@flock = true

Regards
Florian

Am 14.09.2009 um 11:33 schrieb Hans: