Not working wait_for in starting JBoss server via Ansible based on data from logs

It will never match in the last task, because you are searching for the last logfile line plus some extra stuff. You are using a variable in your regex, which contains a string that never matches if you add some other staff at the end of it.

So skip the first and second task and change your search_regex Parameter of the last task.

You could use the ansible fact ansible_date_time (described in Ansible date variable) and use parts of date, time and/or epoch-seconds to build your regex via set_fact module. So your regex will match the logfile line with a timestamp not older then 10 minutes.

With date you could create a timestamp for a specific hour. The playbook could look like this:

---
- name: check logfile last 10 Minutes
  hosts:
  - localhost
  gather_facts: no
  tasks:
  - name: set now timestring
    command: 'date +"%Y-%m-%d %H"'
    register: date_now
  - name: set_now
    set_fact:
      now: "{{ date_now.stdout }}"
  - name: set 10 minutes ago timestring
    command: 'date +"%Y-%m-%d %H" -d "10 minutes ago"'
    register: date_10min_ago
  - name: set 10min_ago
    set_fact:
      ten_min_ago: "{{ date_10min_ago.stdout }}"
  - name: debug
    debug:
      msg: "({{ now }}|{{ ten_min_ago }}).*JBoss EAP.*started.*"
  - name: Wait for server started
    wait_for:
      path: "//home/nityo/application.log"
      search_regex: "({{ now }}|{{ ten_min_ago }}).*JBoss EAP.*started"
      timeout: 600

The Timestamps are totally different if the daliy limit is reached. In the middle of an hour, it seems superfluous. Debug-Output how the regex looks like this:

TASK [debug] **********************
ok: [localhost] => {
    "msg": "(2020-10-12 08|2020-10-12 08).*JBoss EAP.*started.*"
}

What you are storing in last_line_of_the_log_file variable might not be getting matched at the default interval in which wait_for module checks by the time it reaches this task.

Checking service status by parsing a log file can be tricky. However I think the cleanest way will be to match the pattern JBoss EAP.*started.* in the log file. However for this to work reliably, it would be better to start with an empty log file before starting the service.

# Backup the log file with date/time stamp
- shell: cat /home/nityo/application.log >> /home/nityo/application-$(date %b-%d-%H-%M).log

# Empty the file contents before starting service
- command: truncate -s 0 /home/nityo/application.log

- wait_for:
    path: "/home/nityo/application.log"
    search_regex: "JBoss EAP.*started.*"
    timeout: 600

Parsing log files can be hit-or-miss if the logs generate differently in a given span of time. You can tweak the time, retries, and search pattern to get more consistent results.

Update:

It would be good to wait for some time to roll beyond the default lines (10) fetched by tail command, to avoid matching a previous startup. Then use egrep:

# Pause and wait for logs to roll beyond 10 lines fetched by 'tail'
- pause:
    seconds: 30

- shell: tail /home/nityo/application.log | grep -e "JBoss EAP.*started"
  register: file_tail
  until: file_tail is success
  # use appropriate values as per the rate of logging
  retries: 30
  delay: 20