user-tasks-main.yml

---
- name: ensure presence of user
  user:
    name: "{{ item.username }}"
    uid: "{{ item.username }}"
    password: "{{ item.passwd }}"
    comment: "{{ item.comment }}"
    shell: "{{ item.shell }}"
    group: "{{ item.group }}"
    groups: "{{ item.groups }}""

- name: ensure presence of user's ssh key
  authorized_key:
    user: "{{ item.username }}"
    state: present
    key: "{{ item.public_key }}"

- name: os-specific tasks for user
  include: 'os-{{ ansible_distribution }}.yml'

uservars.yml

humanuser1:
  username: humanuser1
  comment: "Human User 1"
  passwd: "shadow-password"
  public_key: "public-key-here"
  uid: 1501
  group: humans
  groups:
    - sudo
    - mygroup1
  shell: "/bin/bash"
  apt_packages:
    - nodejs
    - mongodb
appuser1:
  username: appuser1
  comment: "App User 1"
  passwd: "shadow-password"
  public_key: "public-key-here"
  uid: 1601
  group: apps
  groups:
    - docker
    - mysql
  shell: "/usr/sbin/nologin"