Catch errors and changes in kolla_toolbox module

The kolla_toolbox Ansible module executes as-hoc ansible commands in the
kolla_toolbox container, and parses the output to make it look as if
ansible-playbook executed the command. Currently however, this module
sometimes fails to catch failures of the underlying command, and also
sometimes shows tasks as 'ok' when the underlying command was changed.
This has been tested both before and after the upgrade to ansible 2.8.

This change fixes this issue by configuring ansible to emit output in
JSON format, to make parsing simpler. We can now pick up errors and
changes, and signal them to the caller.

This change also adds an ansible playbook, tests/test-kolla-toolbox.yml,
that can be executed to test the module. It's not currently integrated
with any CI jobs.

Note that this change cannot be backported as the JSON output callback
plugin was added in Ansible 2.5.

Change-Id: I8236dd4165f760c819ca972b75cbebc62015fada
Closes-Bug: #1844114

ansible/library/kolla_toolbox.py

@@ -16,7 +16,6 @@
 
 import docker
 import json
-import re
 
 from ansible.module_utils.basic import AnsibleModule
 
@@ -90,13 +89,6 @@ EXAMPLES = '''
 '''
 
 
-JSON_REG = re.compile('^(?P<host>\w+) \| (?P<status>\w+)!? =>(?P<stdout>.*)$',
-                      re.MULTILINE | re.DOTALL)
-NON_JSON_REG = re.compile(('^(?P<host>\w+) \| (?P<status>\w+)!? \| '
-                           'rc=(?P<exit_code>\d+) >>\n(?P<stdout>.*)\n$'),
-                          re.MULTILINE | re.DOTALL)
-
-
 def gen_commandline(params):
     command = ['ansible', 'localhost']
     if params.get('module_name'):
@@ -138,23 +130,43 @@ def main():
         module.fail_json(msg='kolla_toolbox container is not running.')
 
     kolla_toolbox = kolla_toolbox[0]
-    job = client.exec_create(kolla_toolbox, command_line)
-    output = client.exec_start(job)
+    # Use the JSON output formatter, so that we can parse it.
+    environment = {"ANSIBLE_STDOUT_CALLBACK": "json",
+                   "ANSIBLE_LOAD_CALLBACK_PLUGINS": "True"}
+    job = client.exec_create(kolla_toolbox, command_line,
+                             environment=environment)
+    json_output = client.exec_start(job)
 
-    for exp in [JSON_REG, NON_JSON_REG]:
-        m = exp.match(output)
-        if m:
-            inner_output = m.groupdict().get('stdout')
-            break
-    else:
-        module.fail_json(
-            msg='Can not parse the inner module output: %s' % output)
-
-    ret = dict()
     try:
-        ret = json.loads(inner_output)
-    except ValueError:
-        ret['stdout'] = inner_output
+        output = json.loads(json_output)
+    except Exception as e:
+        module.fail_json(
+            msg='Can not parse the inner module output: %s' % json_output)
+
+    # Expected format is the following:
+    # {
+    #   "plays": [
+    #     {
+    #       "tasks": [
+    #         {
+    #           "hosts": {
+    #             "localhost": {
+    #               <module result>
+    #             }
+    #           }
+    #         }
+    #       ]
+    #     {
+    #   ]
+    # }
+    try:
+        ret = output['plays'][0]['tasks'][0]['hosts']['localhost']
+    except (KeyError, IndexError) as e:
+        module.fail_json(
+            msg='Ansible JSON output has unexpected format: %s' % output)
+
+    # Remove Ansible's internal variables from returned fields.
+    ret.pop('_ansible_no_log', None)
 
     module.exit_json(**ret)
 

tests/test-kolla-toolbox.yml

@@ -0,0 +1,81 @@
+---
+- name: Test the kolla_toolbox module
+  hosts: localhost
+  gather_facts: false
+  tasks:
+    - name: Test successful & unchanged
+      kolla_toolbox:
+        module_name: debug
+        module_args:
+          msg: hi
+      register: result
+
+    - name: Assert result is successful
+      assert:
+        that: result is successful
+
+    - name: Assert result is not changed
+      assert:
+        that: result is not changed
+
+    - name: Test successful & changed
+      kolla_toolbox:
+        module_name: command
+        module_args:
+          echo hi
+      register: result
+
+    - name: Assert result is successful
+      assert:
+        that: result is successful
+
+    - name: Assert result is changed
+      assert:
+        that: result is changed
+
+    - name: Test unsuccessful
+      kolla_toolbox:
+        module_name: command
+        module_args:
+          foo
+      register: result
+      ignore_errors: true
+
+    - name: Assert result is failed
+      assert:
+        that: result is failed
+
+    - name: Test invalid module parameters
+      kolla_toolbox:
+        module_name: debug
+        module_args:
+          foo: bar
+      register: result
+      ignore_errors: true
+
+    - name: Assert result is failed
+      assert:
+        that: result is failed
+
+    - name: Setup for Test successful & changed (JSON format)
+      kolla_toolbox:
+        module_name: file
+        module_args:
+          path: /tmp/foo
+          state: absent
+
+    - name: Test successful & changed (JSON format)
+      kolla_toolbox:
+        module_name: file
+        module_args:
+          path: /tmp/foo
+          state: directory
+      register: result
+
+    - name: Assert result is successful
+      assert:
+        that: result is successful
+
+    - name: Assert result is changed
+      assert:
+        that: result is changed