Variables can be parsed into a rulebook using one or both of these command line arguments:

--vars VARS           Variables file
--env-vars ENV_VARS   Comma separated list of variables to import from the environment

To import variables from a JSON or YAML formatted file, the –vars argument should be used. To import environment variables the –env-vars argument should be used. It is possible to specify multiple environment variables separated by a comma.


Variables that are supplied using the –vars argument will have their data type preserved, but environment variables parsed via –env-vars are always treated as strings. This is important to consider when parsing variables into your rulebook.


In cases where the same variable is supplied via –env-vars and –vars, the one from –env-vars will always take precedence.

Accessing variables in your rulebook

The are two important considerations to take into account when accessing variables in a rulebook:

1. In order to use variables in conditions, the variables supplied at runtime will be placed into a namespace called vars. You must use the vars. prefix followed by the variable name to use variables in conditions.

2. Jinja substitution should be used when accessing variables in any other part of the rulebook, such as in the source configuration or in actions.

Let’s take the following example rulebook:

- name: Testing vars
  hosts: all
    - ansible.eda.range:
        limit: "{{ src_range_limit }}"
    - name: Say Hello
      condition: event.i == vars.match_this_int
          msg: "Hi, I'm {{ MY_NAME }}."

In this rulebook we use three different variables. One, MY_NAME, we will supply using an environment variable. The other two will be supplied in a file called vars.yml which looks like this:

src_range_limit: 4
match_this_int: 2

To run this rulebook we will need to use both –vars and –env-vars to parse the variables into the rulebook. Therefore, we would execute the rulebook as follows:

$ MY_NAME="Bob" ansible-rulebook -i inventory.yml --rulebook hello_there.yml --vars vars.yml --env-vars MY_NAME

Which would return the following output:

2023-02-09 13:37:73.311337 : Hi, I'm Bob


  • To avoid potential issues with variable expansion, we recommend enclosing any value that contains Jinja substituted variables in quotation marks, as shown in the above example.

  • Note the use of the vars. prefix in the condition instead of Jinja substitution, which does not work when used in conditions. Refer to the Conditions page for more information.

Providing extra vars to actions

The run_playbook and run_job_template actions include an optional parameter called extra_vars which can be used for sending extra variables to the respective action. For example, you may have a playbook that runs remediation tasks when an issue with a host is detected, but the playbook requires some variables to be provided at runtime for it to execute properly. This is where the extra_vars parameter comes in.

Extra vars needed by each playbook or job template should be explicitly specified in the extra_vars section under the action in your rulebook. The values of extra vars may be literals, or references to other rulebook variables. In addition to the user supplied runtime variables described above, the rulebook engine will automatically insert event (single match) or events (multiple matches), ruleset and rule under the top level key ansible_eda.

Example run_playbook action:

    name: playbooks/hello.yml
      foo: "{{ FOO }}"
      bar: BAR

Example run_job_template action:

    name: Demo
    organization: Default
          foo: "{{ FOO }}"
          bar: BAR

Example playbook that uses the extra_vars:

- name: Print extra_vars
  hosts: localhost
  gather_facts: false
    - name: Print variable foo set by user
        msg: '{{ foo }}'
    - name: Print variable event set by rulebook engine
        msg: '{{ ansible_eda.event }}'