[chef] Re: possible to call data_bag_item w/in erb template?

["Mark J. Reed" < >]

As Adam said, you don't need to do that in this case, but it's in general a bad idea to have templates that know too much about where their data values come from; it makes your configuration brittle.  If you change your data bag layout, or move the information out of data bags and into attributes, then you have to redo the template (and probably the recipe, too); if you keep the template dumb, only the recipe has to change.

My rule of thumb for templates is: no code other than conditionals and loops, no data lookups other than the passed-in instance variables.   These are more what yout'd call guidelines than strict rules, but I need a really good reason to break them.

On Sat, Oct 8, 2011 at 10:38 AM, Bryan Berry < "> > wrote:

I am trying to call the data_bag_item method within an erb template.  My sudo users may have multiple sudo cmds so i have embedded them directly into the user's databag like so

file: users/oper.json

{

  "id": "oper",

  "groups": "oper",

  "uid": 977,

  "shell": "\/bin\/bash",

  "password": "$1$WV1cZLkt$FmFEuRFCGKWaabud6.Gld1",

  "sudo_cmds": [ "ALL=(ALL) NOPASSWD:/sbin/reboot",

                "ALL=(ALL) NOPASSWD:/sbin/poweroff" ]

}

file: recipes/default.rb

sudoers = []

data_bag('users').each do |user_name|

        u = data_bag_item('users', user_name)

        if u['sudo_cmds']

                sudoers << u['id']

        end

end

template "/etc/sudoers" do

  source "sudoers.erb"

  mode 0440

  owner "root"

  group "root"

  variables(

    :sudoers => sudoers

  )

end

file: sudoers.erb

# User privilege specification

root          ALL=(ALL) ALL

<% @sudoers.each do |user|

        cmds = data_bag_item('users/#{user}', 'sudo_cmds')

        cmds.each do |cmd|  -%>

<%= user %> <%= cmd %>

<%      end

   end -%>

Here is the error i get when I try to do this 

Generated at Sat Oct 08 16:38:16 +0200 2011

Chef::Mixin::Template::TemplateError: 

Chef::Mixin::Template::TemplateError (undefined method `data_bag_item' for #<Erubis::Context:0xb6ffcb64>) on line #12:

 10: 

 11: <% @sudoers.each do |user| 

 12:    cmds = data_bag_item('users/#{user}', 'sudo_cmds')      

 13:    

 14:    cmds.each do |cmd|  -%>

--
Mark J. Reed < "> >