Adding an element to a list of dictionaries with new random string

Question

I have an ansible variable which is a list of dicts:

userdata:
  - { first: Mike, last: Smith, username: msmith}
  - { first: Jane, last: Largo, username: jlargo}
  - { first: Evan, last: Jones, username: ejones}

I would like to add a field to each entry, password that has a randomly generated 20 character alpha-numeric password assigned to each entry so I can use it to as applicable during the playbook for the various actions that need to sync that password to. I tried doing a block:, but learned that you can't do that with_items. I also couldn't find a way to use with_items and save back to that item's dictionary. The password lookup plugin looks promissing to get a random password without having to save it to a file (/dev/null), but I can't seem to get it in each element of the list.

In the end, I would like a structure like this:

userdata:
  - { first: Mike, last: Smith, username: msmith, password: FdUChpPtfonoPexMZmt0}
  - { first: Jane, last: Largo, username: jlargo, password: QR13sN7CP00LbdXZ0gON}
  - { first: Evan, last: Jones, username: ejones, password: OCQSmqCbO8239jHpQiRm}

Answer 1

You need to create a new list looping over your original one. For each item, you combine the existing with the password attribute. The following is an example:

---
- hosts: localhost
  gather_facts: false

  vars:
    userdata:
      - { first: Mike, last: Smith, username: msmith }
      - { first: Jane, last: Largo, username: jlargo }
      - { first: Evan, last: Jones, username: ejones }

  tasks:

    - name: Create a new list with random password
      vars:
        user_entry: "{{ item | combine({'password': lookup('password', '/dev/null')}) }}"
      set_fact:
        users_with_pass: "{{ users_with_pass | default([]) + [user_entry] }}"
      loop: "{{ userdata }}"

    - name: Show result
      debug:
        var: users_with_pass

Which gives:

$ ansible-playbook test.yml 

PLAY [localhost] **************************************************************************************************************************************************************************************************

TASK [Create a new list with random password] *********************************************************************************************************************************************************************
ok: [localhost] => (item={'first': 'Mike', 'last': 'Smith', 'username': 'msmith'})
ok: [localhost] => (item={'first': 'Jane', 'last': 'Largo', 'username': 'jlargo'})
ok: [localhost] => (item={'first': 'Evan', 'last': 'Jones', 'username': 'ejones'})

TASK [Show result] ************************************************************************************************************************************************************************************************
ok: [localhost] => {
    "users_with_pass": [
        {
            "first": "Mike",
            "last": "Smith",
            "password": "w-zk-BAqJuJ090mTy8g0",
            "username": "msmith"
        },
        {
            "first": "Jane",
            "last": "Largo",
            "password": "J6g07utP.ANtbY7Z58Za",
            "username": "jlargo"
        },
        {
            "first": "Evan",
            "last": "Jones",
            "password": "eqHdpKDpkpEBY21qTyz5",
            "username": "ejones"
        }
    ]
}

PLAY RECAP ********************************************************************************************************************************************************************************************************
localhost                  : ok=2    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0