Getting empty merged list when trying to merge two dict lists with multiple when conditions in Ansib-CodePudding

here are my two list -

listone -

list1": 
[
{
    "_ref": "LAB1/1/4094",
    "vlan_id": 12,
    "vlan_name": "test_vlan_1",
    "vlan_subnet": "192.168.1.0/28",
    "vlan_vrf": "vrf_1"
},
{
    "_ref": "LAB2/1/4094",
    "vlan_id": 12,
    "vlan_name": "test_vlan_1",
    "vlan_subnet": "192.168.2.0/28",
    "vlan_vrf": "vrf_1"
}
]

secondlist -

"list2":

[
{
    "_ref": "LAB1/1/4094",
    "vlan_id": "12",
    "vlan_name": "test_vlan_1",
    "vlan_ref": "vlan/ZG5zLnZsYW4kLmNvbS5pbmZvYmxveC5kbnMudmxhbl92aWV3JElORlJBTEFCLjEuNDA5NC4xMg:LAB1/test_vlan_1/12"
}
]

- name: merge lists final
  set_fact:
    merged_list: "{{ merged_list|default([])   [ item[0] | union(item[1]) ] }}"
  when: item[0]._ref == item[1]._ref and item[0].vlan_id == item[1].vlan_id and item[0].vlan_name == item[1].vlan_name
  loop: "{{ query('nested', list1, list2) }}"
- name: print results
  debug:
    var: merged_list

I get output as:

TASK [print results] ***********************************************************
ok: [localhost] => {
    "merged_list": "VARIABLE IS NOT DEFINED!"
}

desired output: in below, if you notice list2 has a match with list1 first dict item so list2 item merged with list1 first item, in the final output i want merged with a match and also unmatched item of list1 which is second one.

"merged_list":

[
{
    "_ref": "LAB1/1/4094",
    "vlan_id": 12,
    "vlan_name": "test_vlan_1",
    "vlan_subnet": "192.168.1.0/28",
    "vlan_vrf": "vrf_1",
    "vlan_ref": "vlan/ZG5zLnZsYW4kLmNvbS5pbmZvYmxveC5kbnMudmxhbl92aWV3JElORlJBTEFCLjEuNDA5NC4xMg:LAB1/test_vlan_1/12"
},
{
    "_ref": "LAB2/1/4094",
    "vlan_id": 12,
    "vlan_name": "test_vlan_1",
    "vlan_subnet": "192.168.2.0/28",
    "vlan_vrf": "vrf_1"
}
]

i believe when: item[0]._ref == item[1]._ref and item[0].vlan_id == item[1].vlan_id and item[0].vlan_name == item[1].vlan_name condition is not working as i expected. Any suggestions/clue to make this work and get merged_list as the way i am looking for.

CodePudding user response：

The items in the lists are dictionaries. You need the filter combine to merge them. For example, the playbook below (simplified for testing)

- hosts: localhost
  vars:
    list1:
      - {_ref: ZG5, name: LAB1, vlan_id: 12, vlan_name: test_vlan_1}
      - {_ref: XXX, name: LAB2, vlan_id: 12, vlan_name: test_vlan_1}
      - {_ref: YYY, name: LAB3, vlan_id: 13, vlan_name: test_vlan_1}
    list2:
      - {_ref: ZG5, vlan_id: 12, vlan_name: test_vlan_1, vlan_ref: vlan/ZG5}
  tasks:
    - set_fact:
        merged_list: "{{ merged_list|d([])   [_item] }}"
      loop: "{{ query('nested', list1, list2) }}"
      vars:
        _conditions:
          - "{{ item.0._ref == item.1._ref }}"
          - "{{ item.0.vlan_id == item.1.vlan_id }}"
          - "{{ item.0.vlan_name == item.1.vlan_name }}"
        _item: "{{ _conditions is all|ternary(item.0|combine(item.1), item.0) }}"
    - debug:
        var: merged_list

gives

merged_list:
  - {_ref: ZG5, name: LAB1, vlan_id: 12, vlan_name: test_vlan_1, vlan_ref: vlan/ZG5}
  - {_ref: XXX, name: LAB2, vlan_id: 12, vlan_name: test_vlan_1}
  - {_ref: YYY, name: LAB3, vlan_id: 13, vlan_name: test_vlan_1}