Ansible notify handlers in another role

Can I notify the handler in another role? What should I do to make ansible find it?

The use case is, e.g. I want to configure some service and then restart it if changed. Different OS have probably different files to edit and even the file format can be different. So I would like to put them into different roles (because the file format can be different, it can't be done by setting group_vars). But the way to restart the service is the same, using service module; so I'd like to put the handler to common role.

Is anyway to achieve this? Thanks.

You can also call handlers of a dependency role. May be cleaner than including files or explicitly listing roles in a playbook just for the purpose of role to role relationship. E.g.:

• roles/my-handlers/handlers/main.yml

  ---
  - name: nginx restart
    service: >
      name=nginx
      state=restarted
  

• roles/my-other/meta/main.yml

  ---
  dependencies:
  - role: my-handlers
  

• roles/my-other/tasks/main.yml

  ---
  - copy: >
      src=nginx.conf
      dest=/etc/nginx/
    notify: nginx restart
  

You should be able to do that if you include the handler file.

Example:

handlers:
  - include: someOtherRole/handlers/main.yml 

But I don't think its elegant.

A more elegant way is to have a play that manages both roles, something like this:

- hosts: all
  roles:
  - role1
  - role2

This will make both roles able to call other handlers.

But again I would suggest to make it all in one role and separate files and use a conditional include http://docs.ansible.com/playbooks_conditionals.html#conditional-imports

Hope that helps

You may import additional handlers from YourRole/handlers/main.yml file by using import_tasks.

So, if MyRole needs to call handlers in some OtherRole, roles/MyRole/handlers/main.yml will look like this:

- import_tasks: roles/OtherRole/handlers/main.yml

Of course roles/MyRole/handlers/main.yml may include additional handlers as well.

This way if I want to run MyRole without running tasks from the OtherRole, ansible will be able to correctly import and run handlers from the OtherRole

I had a similar issue, but needed to take many actions in the other dependent roles.

So rather than invoking the handeler - we set a fact like so:

- name: install mylib to virtualenv
  pip: requirements=/opt/mylib/requirements.txt virtualenv={{ mylib_virtualenv_path }}
  sudo_user: mylib
  register: mylib_wheel_upgraded

- name: set variable if source code was upgraded
  set_fact:
    mylib_source_upgraded: true
  when: mylib_wheel_upgraded.changed

Then elsewhere in another role:

- name: restart services if source code was upgraded
  command: /bin/true
  notify: restart mylib server
  when: mylib_source_upgraded