Ansible - Trouble with conditional

Question

I'm having trouble with a conditional in Ansible. What I'm specifically trying to do is "stat" for the existence of a directory before using the "file" module to create it.

I realize that this process is idempotent, but I have a specific need to check on the existence of the directory first. Reason being, I need the directory to be created and owned by root, before fstab auto-mounts on top of that directory with a different UID/GID.

So, I'm using the code below that I cobbled together from some Googled examples, and another playbook that I run for checking if a file exists before taking another action:

---
- name: Create a directory if it does not exist.
  hosts: server1
  connection: ssh
  tasks:
    - block:
        - name: Check if directory exists.
          ansible.builtin.stat:
            path: '/my_directory'
          register: directory_status
    
        - debug: var=directory_status.stat.path
    
        - name: Create the directory if it does not exist.
          ansible.builtin.file:
            path: /my_directory
            state: directory
            owner: root
            group: root
            mode: '0775'
      when:
        - not directory_status.stat.exists

Unfortunately, I keep getting the following error:

TASK [Check if directory exists.] ******************************************************************************************
task path: /etc/ansible/playbooks/directory.yml:9
fatal: [server1]: FAILED! => {"msg": "The conditional check 'not directory_status.stat.exists' failed. The error was: error while evaluating conditional (not directory_status.stat.exists): 'directory_status' is undefined. 'directory_status' is undefined\n\nThe error appears to be in '/etc/ansible/playbooks/directory.yml': line 9, column 11, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n      - block:\n        - name: Check if directory exists.\n          ^ here\n"}

This is driving me crazy b/c I am following HOWTO's to the letter, and comparing to my other working playbook, and I can't figure out what is going wrong.

I greatly appreciate any help in advance.

THANKS!

Followed this example online: https://italchemy.wordpress.com/2021/10/01/ansible-check-if-a-directory-exists-first-and-then-create-a-new-directory-if-it-does-not-exist/

-ALSO-

Here is some sample code I have that I was using to compare against (I have removed some identifiable pieces to protect my organization):

- name: Register mdatp_onboard.json
  stat:
    path: /etc/opt/microsoft/mdatp/mdatp_onboard.json
  register: mdatp_onboard

- name: Extract WindowsDefenderATPOnboardingPackage.zip into /etc/opt/microsoft/mdatp
  unarchive:
    src: /etc/ansible/files/mdatp/WindowsDefenderATPOnboardingPackage.zip
    dest: /etc/opt/microsoft/mdatp
    mode: 0600
    owner: root
    group: root
  when:
    - "not mdatp_onboard.stat.exists"

- name: Register mdatp_managed.json
  stat:
    path: /etc/opt/microsoft/mdatp/managed/mdatp_managed.json
    register: mdatp_managed

- name: Create Microsoft mdatp_managed.json file from template.
  template:
    src: /etc/ansible/templates/mdatp_managed.json.j2
    dest: /etc/opt/microsoft/mdatp/managed/mdatp_managed.json
    mode: 0600
  when:
    - not mdatp_managed.stat.exists
    #- ansible_distribution_major_version == "8"
    - ansible_os_family == "RedHat"

Answer 1

You have set the when condition on the block, but you're setting the variable inside the block -- so it has not been set at the time you're trying to use it. That is, your logic currently looks like the following pseudocode:

if directory_status.stat.exists then
  directory_status = check_if_directory_exists()
  create_the_directory
endif

It sounds like you want the following instead; note that the indentation of the when condition has changed so that it is now attached to the ansible.builtin.file task instead of the block:

- name: Create a directory if it does not exist.
  hosts: localhost

  tasks:
    - block:
      - name: Check if directory exists.
        ansible.builtin.stat:
          path: '/my_directory'
        register: directory_status

      - debug: var=directory_status.stat.path

      - name: Create the directory if it does not exist.
        ansible.builtin.file:
          path: /my_directory
          state: directory
          owner: root
          group: root
          mode: '0775'
        when:
        - not directory_status.stat.exists

I think things become clearer if you move the when condition to the start of the task:

- name: Create a directory if it does not exist.
  hosts: localhost

  tasks:
    - block:
      - name: Check if directory exists.
        ansible.builtin.stat:
          path: '/my_directory'
        register: directory_status

      - debug: var=directory_status.stat.path

      - name: Create the directory if it does not exist.
        when:
        - not directory_status.stat.exists
        ansible.builtin.file:
          path: /my_directory
          state: directory
          owner: root
          group: root
          mode: '0775'