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ansibleansible-2.xansible-facts

Ansible set_fact not working at all for my task

$ ansible --version
ansible 2.10.8

I believe this is a different issue from Ansible's set_fact not working at all.

I have the following variable defined in group_vars/all.yml

nexus_repo = "dev_builds"
nexus_url = "https://nexus.company.com/{{ nexus_repo }}"

Then on one of my tasks, I do

- name: Adjust nexus_repo value for release builds
  set_fact:
    nexus_repo: "release_builds"
    nexus_url: "https://nexus.company.com/{{ nexus_repo }}"

- debug: msg="{{ nexus_url }}"

When I run my playbook (my-playbook.yml runs my-role.yml), I just see

$ ansible-playbook -i inverntories/hosts.yml -e var_hosts=my-host my-playbook.yml

TASK [my-role : Adjust nexus_repo value for release builds] ****************
ok: [10.227.x.x]

TASK [my-role : debug] *****************************************************
ok: [10.227.x.x] => {
    "msg": "https://nexus.mycompany.com/repository/dev_builds"
}

Why is that?

Solution

  • The problem is that you can't re-use variables declared in the same set_fact. For example, if the variables nexus_repo and nexus_url are declared for the first time in the set_fact below. The task

        - set_fact:
        nexus_repo: release_builds
        nexus_url: "https://nexus.company.com/{{ nexus_repo }}"

    will fail because nexus_url can't use next_repo declared at the previous line:

    The task includes an option with an undefined variable. The error was: 'nexus_repo' is undefined

    This explains the 'strange' behavior you see when the group_vars/all.yml is used

    shell> cat group_vars/all.yml
nexus_repo: dev_builds
nexus_url: "https://nexus.company.com/{{ nexus_repo }}"

    The set_fact below will use the value dev_builds of the variable nexus_repo from group_vars/all.yml when evaluating nexus_url

        - set_fact:
        nexus_repo: release_builds
        nexus_url: "https://nexus.company.com/{{ nexus_repo }}"
    - debug:
        var: nexus_url

    gives

      nexus_url: https://nexus.company.com/dev_builds

    There are more options on how to fix it. For example, don't declare the same variable nexus_url twice

        - set_fact:
        nexus_repo: release_builds
    - debug:
        var: nexus_url

    gives

      nexus_url: https://nexus.company.com/release_builds

    If you have to declare nexus_url new put it into the separate set_fact. For example, the tasks below give the same result

        - set_fact:
        nexus_repo: release_builds
    - set_fact:
        nexus_url: "https://nexus.company.com/{{ nexus_repo }}"
    - debug:
        var: nexus_url

    See the Ansible issue Can't reference a dict key inside the same dict #50280.