Manipulating yaml tree data using Ansible

AA_Manipulating yaml tree data using Ansible.md

Manipulating yaml tree data using Ansible

I sometimes need to convert from a dictionary tree (like in data.yml) to a specific json formatted output file using Ansible.

In this case, I've used a combination of set_fact, a for loop and a combine filter to build my output. I'm also using a regex_search to make sure I'm only getting records where the data I'm interested in is there!

Hope it's useful to people!

data.yml

---
resource_groups: 
  vnetrg:
    vnet:
      transitvnet:
        supernet:
        - "192.0.2.0/25"
        subnet:
          ingresssubnet:
            subnet: "192.0.2.0/27"
          egresssubnet:
            subnet: "192.0.2.32/27"
          appgwsubnet:
            subnet: "192.0.2.64/27"
            udr: "spokert"
        gwsubnet:
          gwsubnet:
            subnet: "192.0.2.96/27"
            udr: "spokert"
      webvnet:
        supernet:
        - "192.0.2.128/27"
        websubnet:
          subnet: "192.0.2.128/27"
          udr: "spokert"
      dbvnet:
        supernet:
        - "192.0.2.192/27"
        dbsubnet:
          subnet: "192.0.2.192/27"
          udr: "spokert"
    udr:
      spokert:
        Internet:
          prefix: "0.0.0.0/0"
          gateway: "192.0.2.62"
  fwrg:
    storage:
    - disks
    lb:
      
  webrg:
    storage:
    - disks
  
  dbrg:
    storage:
    - disks

desired_output.json

{
  "transitvnet": {
    "supernet": ["192.0.2.0/25"],
    "subnet": {"ingresssubnet": {"subnet": "192.0.2.0/27"}, "egresssubnet": {"subnet": "192.0.2.32/27"}, "appgwsubnet": {"subnet": "192.0.2.64/27", "udr": "spokert"}},
    "gwsubnet": {"gwsubnet": {"subnet": "192.0.2.96/27", "udr": "spokert"}},
    "rg": "vnetrg"
  },
  "webvnet": {
    "supernet": ["192.0.2.128/27"],
    "subnet": {"websubnet": {"subnet": "192.0.2.128/27", "udr": "spokert"}},
    "rg": "vnetrg"
  },
  "dbvnet": {
    "supernet": ["192.0.2.192/27"],
    "subnet": {"dbsubnet": {"subnet": "192.0.2.192/27", "udr": "spokert"}},
    "rg": "vnetrg"
  }
}

tasks.yml

- set_fact:
    vnets: "{ {% for vnet in item.value.vnet %}'{{ vnet }}': {{ item.value.vnet[vnet]|combine({'rg': item.key}) }}{% if not loop.last %}, {% endif %}{% endfor %}{% if vnets|default({})|length > 0 %}, {% for vnet in vnets|default({}) %}'{{ vnet }}': {{ vnets[vnet] }}{% if not loop.last %}, {% endif %}{% endfor %}{% endif %} }"
  loop: "{{ resource_groups|dict2items }}"
  loop_control: 
    label: "{{ item.key }}"
  when: item.value|string|regex_search("'vnet':")|type_debug != 'NoneType'