Plugins » Foreman Remote Execution

In foreman 1.15.6 (on CentOS 7.4), I can't get this really simple job template to work.
The template tries to make use of the 'Variable' 'input type'.

<%#
name: freeipa
job_category: Miscellaneous
snippet: false
template_inputs:
- name: foo
  required: false
  input_type: variable
  variable_name: realm
  advanced: false
provider_type: SSH
kind: job_template
%>

echo 'test'
echo <%= input('foo') %>
echo 'done'

'realm' is a top level variable that's present in the ENC output, so should be available for use in the template?

Templates using other input types ('User Input' and 'Fact value') work fine.

The error message is

Failed to initialize: Dynflow::ExecutionPlan::Steps::Error - Failed rendering template: error during rendering: ERF47-9467 [TemplateInput::ValueNotReady]: Input 'foo' is not ready for rendering