[chef] Re: Re: Re: Re: Re: Using variables to define attributes?

[Dan-Joe Lopez < >]

I had a similar idea with the logging. The error I am getting seems to be a "compile” error though, so it doesn't show my 1st logging data…

#DEBUG ATTRIBURE ACCESS
var = node['hostname']
Chef::Log.info var
Chef::Log.info <<-EOH
\n
!!!!!!!!!!!!!!!!!!!!!!!!!!!DEBUG ec2-ATTRIBURE ACCESS!!!!!!!!!!!!!!!!!!!!!!!!!!!
--ec2.instances.ec2-8a4b54410.tags.ec2:owner: #{node[ec2]['instances']['mo-8a4b54410']['tags'][ec2:owner']}
--ec2:owner: #{node['ec2:owner']}
--hostname: #{node['hostname']}
--ec2.instances.[hostname].tags.ec2:owner: #{node[ec2]['instances'][var]['tags'][ec2:owner']}
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
\n
EOH

and the error that I get is:

================================================================================
Recipe Compile Error in C:/ec2/repos/devops_automation/kxen_ga/chef/site-cookbooks/debug/recipes/default.rb
================================================================================

NoMethodError
-------------
undefined method `[]' for nil:NilClass

Cookbook Trace:
---------------
C:/ec2/repos/devops_automation/kxen_ga/chef/site-cookbooks/debug/recipes/default.rb:10:in `from_file'

Relevant File Content:
----------------------
C:/ec2/repos/devops_automation/kxen_ga/chef/site-cookbooks/debug/recipes/default.rb:

3: Chef::Log.info var
4: Chef::Log.info <<-EOH
5: \n
6: !!!!!!!!!!!!!!!!!!!!!!!!!!!DEBUG ec2-ATTRIBURE ACCESS!!!!!!!!!!!!!!!!!!!!!!!!!!!
7: --ec2.instances.ec2-8a4b54410.tags.ec2:owner: #{node['ec2']['instances']['mo-8a4b54410']['tags']['ec2:owner']}
8: --ec2:owner: #{node['ec2:owner']}
9: --hostname: #{node['hostname']}
10>> --ec2.instances.[hostname].tags.ec2:owner: #{node['ec2']['instances'][var]['tags']['ec2:owner']}
11: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
12: \n
13: EOH

Does this help at all?

​

Sent from Windows Mail

From:  " target="_parent">Noah Kantrowitz
Sent: ‎Monday‎, ‎July‎ ‎6‎, ‎2015 ‎5‎:‎30‎ ‎PM
To:  " target="_parent">

If var == 'myhappyhost', those two are equivalent. Most likely some intermediary value is not what you expect. Add some logging to your recipe code:

var = node['hostname']
Chef::Log.info("var = #{var.inspect}")
node['ec2']['instances'][var]....

Don't forget to add `-l info` to the client command line too so it will display the logging output.

--Noah


On Jul 6, 2015, at 5:19 PM, Dan-Joe Lopez < > wrote:

> Thanks for the quick reply Noah.  Unfortunately I don’t have a solid answer to your question.  I am working within an infrastructure that I did not create.  I am not sure what information that I can share with you beyond the below that you might find helpful.
>
> As far as access to other instances information; we have collections of instances organized into projects.  Each project contains a bunch of attributes from all of its instances, so that any instance can see them.
>
> As far as the data not being stored correctly, would that still be a concern, given that manually calling the attribute works as expected when call like this:
> node[‘ec2’][‘instances’][‘myhappyhost’][‘ip’]
> but fails when using the a var in place of the actual hostname:
> node[‘ec2’][‘instances’][var][‘ip’]
> ?
>
> Thanks,
> Dan-Joe Lopez
> Sent from Windows Mail
>
> From: Noah Kantrowitz
> Sent: ‎Monday‎, ‎July‎ ‎6‎, ‎2015 ‎5‎:‎03‎ ‎PM
> To:
>
>
> On Jul 6, 2015, at 4:53 PM, Dan-Joe Lopez < > wrote:
>
> > OHAI Chefs!
> >
> > I don’t know if this is even possible, but I am starting to feel like it is not ☹ Also, I am pretty green, so my advanced apologies if this is a silly question.
> >
> > I would like to call a specific attribute by using a variable, or another attribute.  I cannot find any documentation on the subject, and every method that I have tried has resulted in an error.
> >
> > So, I can call node[‘hostname’] and get the hostname; not a problem.
> > But then let’s say I want to write something that calls an attribute in which the host name is one of the path components… e.g.
> > node[‘ec2’][‘instances’][HOSTNAME][‘ip’]…
> >
> > if I manually type in the host name, no problem:
> > node[‘ec2’][‘instances’][‘myhappyhost’][‘ip’]
> > BOOM: 12.34.56.78
> >
> > but when I try any variation of:
> > node[‘ec2’][‘instances’][node[‘hostname’]][‘ip’]
> > or
> > var = node[‘hostname’]
> > node[‘ec2’][‘instances’][var][‘ip’]
> > node[‘ec2’][‘instances’][“var”][‘ip’]
> > node[‘ec2’][‘instances’][‘var’][‘ip’]
> > node[‘ec2’][‘instances’].var[‘ip’]
> > etc…
> >
> > nothing but errors ☹
> >
> > Am I missing a permutation of syntax here? Is there documentation that would have given me the answer? Is this even possible?
> >
> > Your suggestions and help are appreciated!
>
>
> node['ec2']['instances'][var] is correct, however chances are you are not storing things correctly. How are you populating that node['ec2']['instances'] hash? Nodes cannot see the node attributes of other nodes by default, you need to use the search API or something else to get that data.
>
> --Noah