What is the role and purpose of Handlers in Ansible for automation tasks?

Handlers in Ansible are special tasks that are executed only upon notification by other tasks. Their main purpose is to perform actions that should occur after a change in the system's state, such as restarting a service after updating a configuration file.

Features of Handlers:

• They are executed once at the end of the playbook, even if called multiple times.
• They are only triggered if the task that called them has changed the state.

Example of using a handler to restart a service:

- name: Update configuration file
  copy:
    src: myconfig.conf
    dest: /etc/myapp/config.conf
  notify: Restart myapp

handlers:
  - name: Restart myapp
    service:
      name: myapp
      state: restarted

Thus, handlers help efficiently manage changes and minimize unnecessary service restarts.