How to convert a list into a dictionary?

I can't reuse the content of a variable for two different parameters. (host_groups and tags). (Documentation here)

I have a variable in this form :

probe:
  - name: prob1
    groups:
      - group1
      - group2
  - name: prob2
    groups:
      - group1
      - group3

Then, I have a task that loops for each probes that works well.

- name: Probe
  community.zabbix.zabbix_host:
    host_name: "{{ item.name }}"
    host_groups: "{{ item.groups }}"
  loop: "{{ zabbix_sensor }}"

But I would like to add the values I have in the groups variable in the tags parameter of my task.

- name: Probe
  community.zabbix.zabbix_host:
    host_name: "{{ item.name }}"
    host_groups: "{{ item.groups }}"
    tags: "{{ item.groups }}"
  loop: "{{ zabbix_sensor }}"

This doesn't work because it expects the key in the following format - tag: {{value}}. I don't want to create another tag variable containing the same values as groups because the values will be identical.

The result for this to work would be something like :

- name: Probe
  community.zabbix.zabbix_host:
    host_name: probe1
    host_groups: ['group1','group2']
    tags:
      - tag: group1
      - tag: group2

Any idea how to get there?

I've tried a lot of things, but I can't get my result

Solution

Use the filter community.general.dict_kv to create the dictionary. For example, given the list

  l: 
    - group1
    - group2

declare the dictionary

  d: "{{ l|map('community.general.dict_kv', 'tag') }}"

gives

  d:
    - tag: group1
    - tag: group2

^{Example of a complete playbook for testing
- hosts: localhost

vars:

zabbix_sensor:
- name: prob1
groups:
- group1
- group2
- name: prob2
groups:
- group1
- group3

tasks:

- debug:
msg: |
host_name: {{ item.name }}
host_groups: {{ item.groups }}
tags: {{ item.groups|map('community.general.dict_kv', 'tag') }}
loop: "{{ zabbix_sensor }}"

gives (abridged)
TASK [debug] *********************************************************************************
ok: [localhost] => (item={'name': 'prob1', 'groups': ['group1', 'group2']}) =>
msg: |-
host_name: prob1
host_groups: ['group1', 'group2']
tags: [{'tag': 'group1'}, {'tag': 'group2'}]
ok: [localhost] => (item={'name': 'prob2', 'groups': ['group1', 'group3']}) =>
msg: |-
host_name: prob2
host_groups: ['group1', 'group3']
tags: [{'tag': 'group1'}, {'tag': 'group3'}]}

Q: "Have a tag with name and value."

A: Concatenate the lists

    - debug:
        msg: |
          host_name: {{ item.name }}
          host_groups: {{ item.groups }}
          tags: |
            {{ _tags|to_nice_yaml(indent=2)|indent(2) }}
      loop: "{{ zabbix_sensor }}"
      vars:
        _tags: "{{ item.groups|map('community.general.dict_kv', 'tag') +
                   [{'tag': 'name', 'value': item.name}] }}"

gives

TASK [debug] *********************************************************************************
ok: [localhost] => (item={'name': 'prob1', 'groups': ['group1', 'group2']}) => 
  msg: |-
    host_name: prob1
    host_groups: ['group1', 'group2']
    tags: |
      - tag: group1
      - tag: group2
      - tag: name
        value: prob1
ok: [localhost] => (item={'name': 'prob2', 'groups': ['group1', 'group3']}) => 
  msg: |-
    host_name: prob2
    host_groups: ['group1', 'group3']
    tags: |
      - tag: group1
      - tag: group3
      - tag: name
        value: prob2

^{Q: "For groups, I don't need a value, but in some cases I do."
A: In the example below, any list will be converted to tags only and any other type, expecting a hash, will be converted to the tag and value
- hosts: localhost

vars:

zabbix_sensor:
- name: prob1
attr1: A
attr2: B
groups:
- group1
- group2
regions:
- r1
- r2
- name: prob2
attr1: C
attr2: D
groups:
- group1
- group3
regions:
- r3
- r4

tasks:

- debug:
msg: |
host_name: {{ item.name }}
host_groups: {{ item.groups }}
tags: |
{{ _tags|to_nice_yaml(indent=2)|indent(2) }}
loop: "{{ zabbix_sensor }}"
vars:
_tags_str: |-
{% for k,v in item.items() %}
{% if v|type_debug == 'list' %}
{% for i in v %}
- tag: {{ i }}
{% endfor %}
{% else %}
- tag: {{ k }}
value: {{ v }}
{% endif %}
{% endfor %}
_tags: "{{ _tags_str|from_yaml }}"

gives (abridged)
TASK [debug] *********************************************************************************
ok: [localhost] => (item={'name': 'prob1', 'attr1': 'A', 'attr2': 'B', 'groups': ['group1', 'group2'], 'regions': ['r1', 'r2']}) =>
msg: |-
host_name: prob1
host_groups: ['group1', 'group2']
tags: |
- tag: name
value: prob1
- tag: attr1
value: A
- tag: attr2
value: B
- tag: group1
- tag: group2
- tag: r1
- tag: r2
ok: [localhost] => (item={'name': 'prob2', 'attr1': 'C', 'attr2': 'D', 'groups': ['group1', 'group3'], 'regions': ['r3', 'r4']}) =>
msg: |-
host_name: prob2
host_groups: ['group1', 'group3']
tags: |
- tag: name
value: prob2
- tag: attr1
value: C
- tag: attr2
value: D
- tag: group1
- tag: group3
- tag: r3
- tag: r4}