Implement tag filter strategy

Renames the "artifacting" strategy to "tagfilter" and implements
a more generic tag skipping implementation that can be defined
from within the ansible vars structure dynamically on a per-host,
per-group, or per-playbook basis.

To use the tagfilter strategy, run the playbook with
strategy: tagfilter

and define a hostvar named "skip_tags". Skip tags can be a string
or a list, and any tag CONTAINING a skip tag (an exact match is not
needed) will be skipped.

Also added is a check for a var called "skip_handlers", defaulted
to True. When skip_handlers is enabled, no handlers will be run
regardless of whether the task is skipped or not. If set to False,
handlers will be allowed to run as normal except when tasks are
skipped by the skip_tags.

Change-Id: I649707e6744e03763c4e786d203716ebf657ab48

strategy/tagfilter.py

@@ -13,6 +13,7 @@
 # limitations under the License.
 #
 
+import itertools
 import os
 
 import linear
@@ -21,10 +22,17 @@ import linear
 class StrategyModule(linear.StrategyModule):
     def _queue_task(self, host, task, task_vars, play_context):
         """Wipe the notification system and return for config tasks."""
-        task.notify = None
-        skip_tags = os.environ.get('OS_ANSIBLE_SKIP_TAGS', 'config')
-        skip_tags = skip_tags.split(',')
-        if any([True for i in skip_tags if i in task.tags]):
+        skip_handlers = task_vars.get('skip_handlers', True)
+        if skip_handlers:
+            task.notify = None
+        skip_tags = task_vars.get('skip_tags')
+        if skip_tags:
+            if not hasattr(skip_tags, '__iter__'):
+                skip_tags = (skip_tags,)
+        else:
+            skip_tags = ()
+        if any([True for (i, j) in itertools.product(skip_tags, task.tags)
+               if i in j]):
             return
         else:
             return super(StrategyModule, self)._queue_task(

tests/test-strategy-tagfilter.yml

@@ -0,0 +1,125 @@
+---
+# Copyright 2017, Logan Vig <logan2211@gmail.com>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+- name: Test the tagfilter execution strategy with a list of skip tags
+  hosts: localhost
+  strategy: tagfilter
+  gather_facts: no
+  vars:
+    skip_tags:
+      - skipit
+      - tagskip
+  tasks:
+    - name: Test skipped task
+      debug:
+        msg: "This task is skipped"
+      register: skipped_task
+      tags:
+        # Multiple tags specified before the skip tag to make sure the .product()
+        # loop in the strategy is working properly. (ie. ensure each element in
+        # the skip_tags list is being checked against each element in this tag
+        # list.)
+        - test-tag1
+        - test-tag2
+        - test-tag3
+        - test-tag4
+        - test-skipit
+    - name: Test unskipped task
+      command: /bin/true
+      register: run_task
+      notify: Skipped Handler
+      tags:
+        - test-runit
+  handlers:
+    - name: Skipped Handler
+      debug:
+        msg: "This handler is always skipped"
+      register: skipped_handler
+  post_tasks:
+    - name: Check task run states
+      assert:
+        that:
+          - "skipped_task is not defined"
+          - "run_task | changed"
+          - "skipped_handler is not defined"
+
+- name: Test the tagfilter execution strategy with a string skip tag
+  hosts: localhost
+  strategy: tagfilter
+  gather_facts: no
+  vars:
+    skip_tags: skipit
+  tasks:
+    - name: Test skipped task
+      debug:
+        msg: "This task is skipped"
+      register: skipped_task
+      tags:
+        - test-skipit
+    - name: Test unskipped task
+      command: /bin/true
+      register: run_task
+      notify: Skipped Handler
+      tags:
+        - test-runit
+  handlers:
+    - name: Skipped Handler
+      debug:
+        msg: "This handler is always skipped"
+      register: skipped_handler
+  post_tasks:
+    - name: Check task run states
+      assert:
+        that:
+          - "skipped_task is not defined"
+          - "run_task | changed"
+          - "skipped_handler is not defined"
+
+- name: Test the tagfilter execution strategy with handlers enabled
+  hosts: localhost
+  strategy: tagfilter
+  gather_facts: no
+  vars:
+    skip_handlers: False
+    skip_tags: skipit
+  tasks:
+    - name: Test skipped task
+      command: /bin/true
+      register: skipped_task
+      notify: Skipped Handler
+      tags:
+        - test-skipit
+    - name: Test unskipped task
+      command: /bin/true
+      register: run_task
+      notify: Run Handler
+      tags:
+        - test-runit
+  handlers:
+    - name: Skipped Handler
+      debug:
+        msg: "This handler is always skipped"
+      register: skipped_handler
+    - name: Run Handler
+      command: /bin/true
+      register: run_handler
+  post_tasks:
+    - name: Check task run states
+      assert:
+        that:
+          - "skipped_task is not defined"
+          - "run_task | changed"
+          - "skipped_handler is not defined"
+          - "run_handler | changed"

tests/test.yml

@@ -17,3 +17,5 @@
 - include: test-config_template.yml
 
 - include: test-filters.yml
+
+- include: test-strategy-tagfilter.yml

tox.ini

@@ -32,6 +32,7 @@ setenv =
     ANSIBLE_CONNECTION_PLUGINS={toxinidir}/connection
     ANSIBLE_FILTER_PLUGINS={toxinidir}/filter
     ANSIBLE_LOOKUP_PLUGINS={toxinidir}/lookup
+    ANSIBLE_STRATEGY_PLUGINS={toxinidir}/strategy
     ANSIBLE_LIBRARY={toxinidir}/library