Get return status from shell script and call a custom resource based on that

Chef Infra (archive)
1

Hi all , I am new to chef and what I am trying to do is run a bash script which from chef which will return some status and based on the that status I have to run a custom_resource.

The following is code I am trying to run.

var = false

ruby_block ‘something’ do
block do
var = shell_out(“sh my_script.sh”).status.success?
end
end

if var
custom_resource “my_resource” do
action :run
end
end

As the value of var is checked at compile time, “if” is always false, is there a way to retain value of var outside ruby block or any other way to get status from shell script and call custom_resource at compile time.
I have also tried notify inside ruby_block, but it also gives error because of custom_resource.

2

Hi,

For easier reading, please use the Discourse formatting in future posts. This will make helping you a lot easier.
Chef has guards [1] that can be used on any resource, also on custom resources, that allow shell interpretation. So what you want could be achieved with something like this:

custom_resource “my_resource” do
  action :run
  only_if "/path/to/my_script.sh"
end

[1] https://docs.chef.io/resource_common.html#guards

3

Hi joerg.herzinger,

Thanks for quick reply, just wanted to ask that if this solution will face the compile time vs converge time problem or not.

4

Actually, the very first sentence of the guard documentation I linked answers that question. :wink:

5

Okay, got it, Thanks for your help :smile: