added handlers_from (#49220)

* added handlers_from

fixes #46769

changelogs/fragments/from_handlers.yml

@@ -0,0 +1,2 @@
+minor_changes:
+    - add from_handlers option to include_role/import_role

lib/ansible/modules/utilities/logic/import_role.py

@@ -48,6 +48,11 @@ options:
       - Overrides the role's metadata setting to allow using a role more than once with the same parameters.
     type: bool
     default: 'yes'
+  handlers_from:
+    description:
+      - File to load from a role's C(handlers/) directory.
+    default: main
+    version_added: '2.8'
 notes:
   - Handlers are made available to the whole play.
   - "Since Ansible 2.7: variables defined in C(vars) and C(defaults) for the role are exposed at playbook parsing time.

lib/ansible/modules/utilities/logic/include_role.py

@@ -61,6 +61,11 @@ options:
     type: bool
     default: 'no'
     version_added: '2.7'
+  handlers_from:
+    description:
+      - File to load from a role's C(handlers/) directory.
+    default: main
+    version_added: '2.8'
 notes:
   - Handlers are made available to the whole play.
   - Before Ansible 2.4, as with C(include), this task could be static or dynamic, If static, it implied that it won't

lib/ansible/playbook/role/__init__.py

@@ -230,7 +230,7 @@ class Role(Base, Become, Conditional, Taggable):
                 raise AnsibleParserError("The tasks/main.yml file for role '%s' must contain a list of tasks" % self._role_name,
                                          obj=task_data, orig_exc=e)
 
-        handler_data = self._load_role_yaml('handlers')
+        handler_data = self._load_role_yaml('handlers', main=self._from_files.get('handlers'))
         if handler_data:
             try:
                 self._handler_blocks = load_list_of_blocks(handler_data, play=self._play, role=self, use_handlers=True, loader=self._loader,

lib/ansible/playbook/role_include.py

@@ -41,7 +41,7 @@ class IncludeRole(TaskInclude):
     """
 
     BASE = ('name', 'role')  # directly assigned
-    FROM_ARGS = ('tasks_from', 'vars_from', 'defaults_from')  # used to populate from dict in role
+    FROM_ARGS = ('tasks_from', 'vars_from', 'defaults_from', 'handlers_from')  # used to populate from dict in role
     OTHER_ARGS = ('apply', 'public', 'allow_duplicates')  # assigned to matching property
     VALID_ARGS = tuple(frozenset(BASE + FROM_ARGS + OTHER_ARGS))  # all valid args
 

test/integration/targets/handlers/from_handlers.yml

@@ -0,0 +1,41 @@
+- name: verify handlers_from on include_role
+  hosts: A
+  gather_facts: False
+  connection: local
+  tags: ['scenario1']
+  tasks:
+    - name: test include_role
+      include_role: name=test_handlers_meta handlers_from=alternate.yml
+
+    - name: force handler run
+      meta: flush_handlers
+
+    - name: verify handlers ran
+      assert:
+        that:
+            - "'handler1_alt_called' in hostvars[inventory_hostname]"
+            - "'handler2_alt_called' in hostvars[inventory_hostname]"
+      tags: ['scenario1']
+
+
+- name: verify handlers_from on import_role
+  hosts: A
+  gather_facts: False
+  connection: local
+  tasks:
+    - name: set facts to false
+      set_fact:
+        handler1_alt_called: False
+        handler2_alt_called: False
+
+    - import_role: name=test_handlers_meta handlers_from=alternate.yml
+
+    - name: force handler run
+      meta: flush_handlers
+
+    - name: verify handlers ran
+      assert:
+        that:
+            - handler1_alt_called|bool
+            - handler2_alt_called|bool
+      tags: ['scenario1']

test/integration/targets/handlers/roles/test_handlers_meta/handlers/alternate.yml

@@ -0,0 +1,12 @@
+- name: set_handler_fact_1
+  set_fact:
+    handler1_called: True
+    handler1_alt_called: True
+
+- name: set_handler_fact_2
+  set_fact:
+    handler2_called: True
+    handler2_alt_called: True
+
+- name: count_handler
+  shell: echo . >> {{ handler_countpath }}

test/integration/targets/handlers/runme.sh

@@ -2,7 +2,12 @@
 
 set -eux
 
+# simple handler test
 ansible-playbook test_handlers.yml -i inventory.handlers -v "$@" --tags scenario1
+
+# simple from_handlers test
+ansible-playbook from_handlers.yml -i inventory.handlers -v "$@" --tags scenario1
+
 ansible-playbook test_listening_handlers.yml -i inventory.handlers -v "$@"
 
 [ "$(ansible-playbook test_handlers.yml -i inventory.handlers -v "$@" --tags scenario2 -l A \