In the post Handy Ansible Logic I described a situation where moving ansible logic out of when: statement and into an inline Jinja achieved a much cleaner solution. Recently, I had a similar situation where I needed to extend what I was doing in the Jinja. This time, I needed to dynamically construct the a variable to pass into a modules parameter.

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- name: Example 1 - Set facts
    set_fact:
      output: >-
        {%- set output_list = [] -%}
        {%- for server in ip_list -%}
          {%- set my_server = {'name': server.name, 'type': 'IPv4'} -%}
          {{ output_list.append( my_server ) }}
        {%- endfor -%}
        {{ output_list }}

Recently I was writing what initially looked like a pretty straight forward ansible play. Everything was progressing quite well until I came to a point where I needed to set one variable, only when another variable was set. My first pass at this logic was to repeat the task, and control which task was run with a when: statement. This worked, but just wasn’t ideal with all of the duplicated code. I just knew there had to be a better way and there was.