How to assign an array to a variable in an Ansible-Playbook

Question

In a playbook I got the following code:

---
- hosts: db
  vars:
    postgresql_ext_install_contrib: yes
    postgresql_pg_hba_passwd_hosts: [\'10.129.181.241         


        

Answer 1

You can assign a list to variable by set_fact and ansible filter plugin.

Put custom filter plugin to filter_plugins directory like this:

(ansible top directory)
site.yml
hosts
filter_plugins/
    to_group_vars.py

to_group_vars.py convert hostvars into list that selected by group.

from ansible import errors, runner
import json

def to_group_vars(host_vars, groups, target = 'all'):
    if type(host_vars) != runner.HostVars:
        raise errors.AnsibleFilterError("|failed expects a HostVars")

    if type(groups) != dict:
        raise errors.AnsibleFilterError("|failed expects a Dictionary")

    data = []
    for host in groups[target]:
        data.append(host_vars[host])
    return data

class FilterModule (object):
    def filters(self):
        return {"to_group_vars": to_group_vars}

Use like this:

---
- hosts: all
  tasks:
  - set_fact:
      web_ips: "{{hostvars|to_group_vars(groups, 'web')|map(attribute='ansible_eth0.ipv4.address')|list }}"
  - debug:
      msg: "web ip is {{item}}/32"
    with_items: web_ips