How can I filter certain element in a string

playbook.yml

---
  hosts: local_host
  connection: local
  gather_facts: False
  tasks:
  - name: set-details
    set_fact:
      filter: "{{ lookup('file', 'tmp/task2.yml') | from_json }}"

  - set_fact:
      result: "{{ filter['msg'] }}"

  - debug:
      var: result

task2.yml

{
    "ansible_loop_var": "item",
    "_ansible_no_log": false,
    "invocation": {
        "module_args": {
            "wait_for_task": true,
            "policy_package": "Mills07_Simplified",
            "version": null,
            "wait_for_task_timeout": 30
        }
    },
    "item": "Mills07_Simplified",
    "changed": false,
    "msg": "Task Verify policy operation with task id 01234567-89ab-cdef-928b-bef7e174fc7a failed. Look at the logs for more details",
    "_ansible_item_label": "Mills07_Simplified"
}

debug message

TASK [debug] *****************************************************************************************************************************************************************************
ok: [localhost] => {
    "result": "Task Verify policy operation with task id 01234567-89ab-cdef-928b-bef7e174fc7a failed. Look at the logs for more details"
}

When I did the following,

  - set_fact:
      task_id: "{{ result |
                   select('regex', my_regex)|
                   first|
                   regex_replace(my_regex, my_replace) }}"

      vars:
        my_regex: '^Task Verify policy operation with task id (.*)$'
        my_replace: '\1'
  - debug:
      var: task_id

I got an error message

fatal: [localhost]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'my_regex' is undefined\n\nThe error appears to be in

Goal: I want to get the task-id "01234567-89ab-cdef-928b-bef7e174fc7a"

How can I get this string 01234567-89ab-cdef-928b-bef7e174fc7a

Solution

Since you are looking for a universally unique identifier (or UUID) which has a defined format of 8-4-4-4-12 characters for a total of 36 characters (32 hexadecimal characters and 4 hyphens) ^source, you can use a simple regex to extract it.

It can be handled with the following regex:

[0-9a-f]{8}-(?:[0-9a-f]{4}-){3}[0-9a-f]{12}

^{You can test it there: https://regex101.com/r/4Hs7il/1}

So, in a set_fact:

- set_fact:
    uuid: >- 
      {{ filter.msg 
          | regex_search(
              '([0-9a-f]{8}-(?:[0-9a-f]{4}-){3}[0-9a-f]{12})', 
              '\1', 
              ignorecase=True
            ) 
          | first 
      }}

As an example:

- set_fact:
    uuid: >- 
      {{ filter.msg 
          | regex_search(
              '([0-9a-f]{8}-(?:[0-9a-f]{4}-){3}[0-9a-f]{12})', 
              '\1', 
              ignorecase=True
            ) 
          | first 
      }}
  vars:
    filter:
      msg: >-
        Task Verify policy operation with task
        id 01234567-89ab-cdef-928b-bef7e174fc7a failed.
        Look at the logs for more details
- debug:
    var: uuid

Would yield:

TASK [set_fact] ***************************************************
ok: [localhost]

TASK [debug] ******************************************************
ok: [localhost] => 
  uuid: 01234567-89ab-cdef-928b-bef7e174fc7a