How to get a formatted line from a dictionary var?

I'm pretty new to Ansible and I'm not sure how to get it right.

To start with, I have implemented this dictionary var for an exemple. There is 2 values but it could be a greater number:

tf_ETCD:
  1:
    hostname: Etcd01
    ip: 192.168.1.141
  2:
    hostname: Etcd02
    ip: 192.168.1.142

I'd like the result to be formatted like that:

{{ tf_ETCD1_Host }}=https://{{ tf_ETCD1_IP }}:2380,{{ tf_ETCD2_Host }}=https://{{ tf_ETCD2_IP }}:2380

So I kinda get it by looping over the list via this code:

    - name: Format each value
      set_fact:
        etcd: "{{ item.value.hostname }}=https://{{ item.value.ip }}:2380,"
      loop: "{{ lookup('ansible.builtin.dict', tf_ETCD) }}"
      register: etcd_query

    - name: Examine the joined string
      debug:
        msg: "{{ etcd_query['results'][0]['ansible_facts']['etcd'] }}{{ etcd_query['results'][1]['ansible_facts']['etcd'] }}"

The result gave me:

TASK [Format each values] **********************************************************************************************
ok: [] => (item={'key': 1, 'value': {'hostname': 'Etcd01', 'ip': '192.168.1.141'}})
ok: [] => (item={'key': 2, 'value': {'hostname': 'Etcd02', 'ip': '192.168.1.142'}})

TASK [Examine the joined string] ***************************************************************************************
ok: [] => {
    "msg": "Etcd01=https://192.168.1.141:2380,Etcd02=https://192.168.1.142:2380,"
}

I cannot figure out how to do a "foreach loop result" in my "Examine the joined string" play.

If you can give me a hint or the concept I'm looking for, you'll save my day.

Solution

Figure out how to do a "foreach loop result" in my "Examine the joined string" play ...

A minimal example playbook

---
- hosts: localhost
  become: false
  gather_facts: false

  vars:

    tf_ETCD:
      1:
        hostname: Etcd01
        ip: 192.0.2.1
      2:
        hostname: Etcd02
        ip: 192.0.2.2

  tasks:

  - debug:
      msg: "{{ tf_ETCD[ansible_loop.index] }}"
    loop: "{{ range(0, tf_ETCD | length, 1) | list }}"
    loop_control:
      extended: true

  - set_fact:
      etcd: "{{ etcd | d('') + tf_ETCD[ansible_loop.index].hostname ~ '=https://' ~ tf_ETCD[ansible_loop.index].ip ~ ':2380,' }}"
    loop: "{{ range(0, tf_ETCD | length, 1) | list }}"
    loop_control:
      extended: true

  - debug:
      msg: "{{ etcd }}"

will result into an output of

TASK [debug] ******************************************************
ok: [localhost] => (item=0) =>
  msg:
    hostname: Etcd01
    ip: 192.0.2.1
ok: [localhost] => (item=1) =>
  msg:
    hostname: Etcd02
    ip: 192.0.2.2

TASK [debug] ******************************************************
ok: [localhost] =>
  msg: Etcd01=https://192.0.2.1:2380,Etcd02=https://192.0.2.2:2380,

Some Hints