# Request global variable

**URL:** <https://www.ruby-forum.com/t/request-global-variable/112309>\
**Category:** Rails\
**Created:** [August 17, 2007, 10:45am UTC](https://www.ruby-forum.com/t/request-global-variable/112309 "2007-08-17T10:45:19Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Jesper\_Andersen](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/e47c2d/32.png) [@Jesper\_Andersen](https://www.ruby-forum.com/u/Jesper_Andersen)\
**Post date:** [August 17, 2007, 10:45am UTC](https://www.ruby-forum.com/t/request-global-variable/112309/1 "2007-08-17T10:45:19Z")

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I need information about the user currently logged in available outside  
of  
controllers. At least in models but probably also in some library code.  
I don’t want to pass the user object around everywhere. That is ugly and  
annoying. So I wanted to make it available somewhere globally to a  
single  
request by some before filter that creates the user object from a user  
id  
stores in session.

Global variables are too global. They are outside the scope of a  
request.  
I have tried the above with Thread.current[:user] for the user object.  
It  
seems to work, but is it a good way? I assume a thread may be used for  
several requests so if I am not careful the user object may be passed to  
some later request? Should I make a after\_filter that assigns nil?  
Is there a better way to do this?

–  
Jesper  
16:29:22 up 6:36, 9 users, load average: 0.47, 0.39, 0.32

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<div class="post-metadata">

**Author:** ![Jesper\_Andersen](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/e47c2d/32.png) [@Jesper\_Andersen](https://www.ruby-forum.com/u/Jesper_Andersen)\
**Post date:** [August 17, 2007, 1:39pm UTC](https://www.ruby-forum.com/t/request-global-variable/112309/2 "2007-08-17T13:39:47Z")

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Jesper Andersen wrote:

> I need information about the user currently logged in available outside  
> of  
> controllers. At least in models but probably also in some library code.  
> I don’t want to pass the user object around everywhere. That is ugly and  
> annoying. So I wanted to make it available somewhere globally to a  
> single  
> request by some before filter that creates the user object from a user  
> id  
> stores in session.

Sounds like you’re already familiar with filters and the like, so I  
won’t bore you with those details, but you can get the same effect as a  
global variable by adding a reader and writer to Object. Probably the  
easiest way is to add something to your environment.rb:

def outside  
@outside  
end

def outside=(value)  
@outside = value  
end

Now you can call self.outside = “blah” and the method outside can be  
called from anywhere (at least everywhere I tested :).

Could this code be executed out side of the context of a web request?  
Your code will not work well in those situations, for example you are  
mandating that unit tests will have to set a “current user”.

In models you typically set the user once, and then forget it and let  
the database do all the remembering. Make sure you’re not hanging  
yourself.

Eli