resources_common_guard_interpreter_attributes_inherit.md

The guard_interpreter property is set to :default by default for the bash, csh, perl, python, and ruby resources. When the guard_interpreter property is set to :default, not_if or only_if guard statements do not inherit properties that are defined by the script-based resource.

Warning

The batch and powershell_script resources inherit properties by default. The guard_interpreter property is set to :batch or :powershell_script automatically when using a not_if or only_if guard statement within a batch or powershell_script resource, respectively.

For example, the `not_if` guard statement in the following resource example **does not inherit** the `environment` property:

bash 'javatooling' do
  environment 'JAVA_HOME' => '/usr/lib/java/jdk1.7/home'
  code 'java-based-daemon-ctl.sh -start'
  not_if 'java-based-daemon-ctl.sh -test-started'
end

and requires adding the environment property to the not_if guard statement so that it may use the JAVA_HOME path as part of its evaluation:

bash 'javatooling' do
  environment 'JAVA_HOME' => '/usr/lib/java/jdk1.7/home'
  code 'java-based-daemon-ctl.sh -start'
  not_if 'java-based-daemon-ctl.sh -test-started', :environment => 'JAVA_HOME' => '/usr/lib/java/jdk1.7/home'
end

To inherit properties, add the guard_interpreter property to the resource block and set it to the appropriate value:

• :bash for bash
• :csh for csh
• :perl for perl
• :python for python
• :ruby for ruby

For example, using the same example as from above, but this time adding the guard_interpreter property and setting it to :bash:

bash 'javatooling' do
  guard_interpreter :bash
  environment 'JAVA_HOME' => '/usr/lib/java/jdk1.7/home'
  code 'java-based-daemon-ctl.sh -start'
  not_if 'java-based-daemon-ctl.sh -test-started'
end

The not_if statement now inherits the environment property and will use the JAVA_HOME path as part of its evaluation.