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Ansible - Create Users from a Dictionary

Creating users is typically straightforward as the documentation for the required Ansible modules is comprehensive and easy to navigate. However, working with dictionaries instead of lists can introduce some additional complexity. 
For example, let's assume the following dictionary structure is given:
 usergroups:  
   group1:  
     gid: 10001  
     name: group1  
   group2:  
     gid: 10002  
     name: group2  
   group3:  
     gid: 10003  
     name: group3  
   group4:  
     gid: 10004  
     name: group4  
 users:  
   user1:  
     uid: 1985  
     name: user1  
     groups:  
       - group1  
       - group2  
     sshkeys:  
       - ssh-ed25519 AAAA0  
       - ssh-ed25519 AAAA1  
   user2:  
     uid: 1986  
     name: user2  
     groups:  
       - group4  
       - group1  
     sshkeys:  
       - ecdsa-sha2-nistp384 AAAA0
Ansible provides the dict2items filter which transforms a dictionary into a list of key-value pairs. This transformation allows you to iterate over a list created from the dictionary and access all attributes for use within your Ansible modules:
 - name: create usergroups  
   with_items: "{{ users | ansible.builtin.dict2items }}"  
   ansible.builtin.group:  
     gid: "{{ item['value']['uid'] }}"  
     name: "{{ item['value']['name'] }}"  
     state: present  
     system: false
Same goes for the groups:
 - name: create groups  
   with_items: "{{ usergroups | ansible.builtin.dict2items }}"  
   ansible.builtin.group:  
     gid: "{{ item['value']['gid'] }}"  
     name: "{{ item['value']['name'] }}"  
     state: present  
     system: false

For user creation, additional logic is required to generate and hash strong passwords. Each user will be assigned a unique password with the following characteristics:

  • Length: 96 characters
  • Character set: A combination of uppercase letters, lowercase letters, and digits
 - name: create users  
   with_items: "{{ users | ansible.builtin.dict2items }}"  
   ansible.builtin.user:  
     uid: "{{ item['value']['uid'] }}"  
     name: "{{ item['value']['name'] }}"  
     comment: "{{ item['value']['full_name'] | default(item['value']['name']) | capitalize }}"  
     append: false  
     create_home: true  
     generate_ssh_key: false  
     group: "{{ item['value']['name'] }}"  
     groups: "{{ item['value']['groups'] }}"  
     home: "/home/{{ item['value']['name'] }}"  
     move_home: false  
     password: "{{ lookup('ansible.builtin.password', '/dev/null', length=96, chars=['ascii_lowercase','ascii_uppercase','digits']) | password_hash('sha512_crypt') }}"  
     update_password: on_create  
     shell: "{{ item['value']['shell'] | default('/bin/bash') }}"  
     state: present  
     system: false
You might have noticed that passwords are generated for each user, but not returned to the user as they're returned to '/dev/null'. Instead of relying on passwords for authentication, the SSH keys specified in each user's 'sshkeys' attribute will be used to configure passwordless SSH access using the 'authorized_key' module from the 'ansible.posix' collection:
 - name: configure ssh keys  
   with_items: "{{ users | ansible.builtin.dict2items }}"  
   ansible.posix.authorized_key:  
     user: "{{ item['value']['name'] }}"  
     exclusive: true  
     state: present  
     key: "{{ item['value']['sshkeys'] | join('\n') }}"
The authorized_key module requires the key attribute to be a string. Therefore, we'll need to combine the list of SSH keys specified for each user into a single string using the join() filter before applying them to the user's authorized_keys file.

The completed playbook looks like this:
 ---  
 - name: create users on test hosts  
   hosts: test  
   become: true  
   gather_facts: true  
   vars:  
     usergroups:  
       group1:  
         gid: 10001  
         name: group1  
       group2:  
         gid: 10002  
         name: group2  
       group3:  
         gid: 10003  
         name: group3  
       group4:  
         gid: 10004  
         name: group4  
     users:  
       user1:  
         uid: 1985  
         name: user1  
         groups:  
           - group1  
           - group2  
         sshkeys:  
           - ssh-ed25519 AAAA0  
           - ssh-ed25519 AAAA1  
       user2:  
         uid: 1986  
         name: user2  
         groups:  
           - group4  
           - group1  
         sshkeys:  
           - ecdsa-sha2-nistp384 AAAA0  
   collections:  
     - ansible.builtin  
     - ansible.posix  
   tasks:  
     - name: create usergroups  
       with_items: "{{ users | ansible.builtin.dict2items }}"  
       ansible.builtin.group:  
         gid: "{{ item['value']['uid'] }}"  
         name: "{{ item['value']['name'] }}"  
         state: present  
         system: false  
     - name: create groups  
       with_items: "{{ usergroups | ansible.builtin.dict2items }}"  
       ansible.builtin.group:  
         gid: "{{ item['value']['gid'] }}"  
         name: "{{ item['value']['name'] }}"  
         state: present  
         system: false  
     - name: create users  
       with_items: "{{ users | ansible.builtin.dict2items }}"  
       ansible.builtin.user:  
         uid: "{{ item['value']['uid'] }}"  
         name: "{{ item['value']['name'] }}"  
         comment: "{{ item['value']['full_name'] | default(item['value']['name']) | capitalize }}"  
         append: false  
         create_home: true  
         generate_ssh_key: false  
         group: "{{ item['value']['name'] }}"  
         groups: "{{ item['value']['groups'] }}"  
         home: "/home/{{ item['value']['name'] }}"  
         move_home: false  
         password: "{{ lookup('ansible.builtin.password', '/dev/null', length=96, chars=['ascii_lowercase','ascii_uppercase','digits']) | password_hash('sha512_crypt') }}"  
         update_password: on_create  
         shell: "{{ item['value']['shell'] | default('/bin/bash') }}"  
         state: present  
         system: false  
     - name: configure ssh keys  
       with_items: "{{ users | ansible.builtin.dict2items }}"  
       ansible.posix.authorized_key:  
         user: "{{ item['value']['name'] }}"  
         exclusive: true  
         state: present  
         key: "{{ item['value']['sshkeys'] | join('\n') }}"  
 ...
If possible, using a list of users, each containing the relevant attributes (username, uid, groups, SSH keys, etc.), would significantly simplify the playbook and improve its readability.

Feel free to comment and / or suggest a topic.
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