# Ruby/rails/debugger variable dump question

**URL:** <https://www.ruby-forum.com/t/ruby-rails-debugger-variable-dump-question/180680>\
**Category:** Ruby\
**Created:** [December 25, 2009, 5:53pm UTC](https://www.ruby-forum.com/t/ruby-rails-debugger-variable-dump-question/180680 "2009-12-25T17:53:39Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![ralphshnelvar](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/e19adc/32.png) [@ralphshnelvar](https://www.ruby-forum.com/u/ralphshnelvar)\
**Post date:** [December 25, 2009, 5:53pm UTC](https://www.ruby-forum.com/t/ruby-rails-debugger-variable-dump-question/180680/1 "2009-12-25T17:53:39Z")

</div>

newb here.

(OT: Merry Christmas, all.)

So I placed a debugger statement into my ROR app and run  
ruby script/server webrick --debugger

My app hit the debugger statement.

I then did a  
var local

* * *

(rdb:68) var local  
\_ =\>  
exception =\> No route matches “/xxx” with {:method=\>:get}  
handler =\> #\<Method: #\<ApplicationController:0x6018a3c  
@action\_name=“index”, @\_response=#\<ActionController::Response:0x6018b40  
@session={“flash”=\>{}}, @redirected\_to=nil,

[snipped a ton of stuff]

## “HTTP\_ACCEPT”=\>“text/html,application/xhtml+xml, application/xml;q=0.9,_/_;q=0.8”, “REQUEST\_METHOD”=\>“GET”, “HTTP\_CONNECTION”=\>“keep-alive”}, @request\_method=:get, @parameters={}\>, @parameters={}\>\>.\_\_bind\_1261677328\_946000\> (rdb:68)

I have no idea how to interpret this or format this for pretty output.

So … by guess and by gosh (and because I read it somewhere) I then ran  
irb inside the debugger and did

* * *

(rdb:68) @\_response  
#\<ActionController::Response:0x6018b40 @session={“flash”=\>{}},  
@redirected\_to=nil,  
@writer=#Proc:0x0612469c@f:/Ralph-Rails-Apps/authlogic/vendor/rails/actionpack/lib/action\_controller/response.rb:46,  
@request=#\<ActionController::Request:0x6018b68

[snipped a ton of stuff]

## @assigns={}, @helpers=#ActionView::Base::ProxyModule:0x6018960\>, @body=["", nil, [], []], @assigns=[], @header={“Cache-Control”=\>“no-cache”}, @status=200\>

Since that was no better, I tried (because I saw it somewhere)  
y @\_response  
inside irb

I don’t even see y documented as a debugger command.

* * *

irb(#ApplicationController:0x6018a3c):002:0\> y @\_response  
— &id007 !ruby/object:ActionController::Response  
assigns: &id001 []

block:  
body:

- “”
- 
- \*id001
- []

header: &id005 !map:Rack::Utils::HeaderHash  
Cache-Control: no-cache  
redirected\_to:  
request: &id003 !ruby/object:ActionController::Request  
content\_type:  
env:  
rack.session.record:  
!ruby/object:ActiveRecord::SessionStore::Session  
attributes:  
updated\_at: 2009-12-24 06:54:00  
session\_id: fab30d62f08ae89e5b87d68bb1647c3c  
id: “1”  
created\_at: 2009-12-24 06:54:00  
data: |  
BAh7BiIKZmxhc2hJQzonQWN0aW9uQ29udHJvbGxlcjo6Rmxhc2g6OkZsYXNo  
SGFzaHsABjoKQHVzZWR7AA==

```
  attributes_cache: {}

  data:
    flash: &id002 !map:ActionController::Flash::FlashHash {}

action_controller.rescue.request: *id003
SERVER_NAME: localhost
rack.request.cookie_hash:
  _session_id: fab30d62f08ae89e5b87d68bb1647c3c

```

[snipped a ton of stuff]

```
  request: *id003

```

helpers: !ruby/object:ActionView::Base::ProxyModule  
receiver: \*id008  
view\_paths: !seq:ActionView::PathSet  
- !ruby/object:ActionView::ReloadableTemplate::ReloadablePath  
disk\_cache: {}

```
  path: f:/Ralph-Rails-Apps/authlogic/app/views
  paths: {}

```

writer: !ruby/object:Proc {}

=\> nil  
irb(#ApplicationController:0x6018a3c):003:0\>

* * *

That’s a bit better but still mostly uninterpretable to me.

So … how would I get programmatic access to, say, SERVER\_NAME or the  
\_session\_id?

Is there documentation on how to use the debugger?