From 58b8ca09fc71f56ff5c09b768123336178bbd4e0 Mon Sep 17 00:00:00 2001
From: Jill Rouleau <jill.rouleau@canonical.com>
Date: Wed, 13 Sep 2017 17:21:11 -0700
Subject: [PATCH] Add action to check rmq queues

Report back to the user any queues with greater than N messages.

Change-Id: Ia39c05a4fe0ce74682af24ffe3d17d3006001b62
Closes-Bug: 1716981
---
 actions.yaml               | 19 ++++++++++++++++++-
 actions/actions.py         | 30 +++++++++++++++++++++++++++++-
 actions/check-queues       |  1 +
 tests/basic_deployment.py  |  7 +++++++
 unit_tests/test_actions.py | 34 ++++++++++++++++++++++++++++++++++
 5 files changed, 89 insertions(+), 2 deletions(-)
 create mode 120000 actions/check-queues

diff --git a/actions.yaml b/actions.yaml
index 2a78267f..8029a5ee 100644
--- a/actions.yaml
+++ b/actions.yaml
@@ -3,4 +3,21 @@ pause:
 resume:
   descrpition: Resume the rabbitmq unit.
 cluster-status:
-  description: Show the current cluster status.
\ No newline at end of file
+  description: Show the current cluster status.
+check-queues:
+  description: |
+    Show current queues, optionally only show queues with more than N messages
+    or queues from specified vhost.
+  params:
+    queue-depth:
+      type: integer
+      default: -1
+      description: |
+        Only show queues with >= this many messages. -1 shows all.  Note that
+        if the result exceeds command line length (1/4 ulimit -s) on the target
+        system this will fail  (For ex; -1 in an openstack env)
+        See lp:1437366, lp:1274460
+    vhost:
+      type: string
+      default: "/"
+      description:  Show queues from the specified vhost.  Eg; "openstack".
diff --git a/actions/actions.py b/actions/actions.py
index 94c81ce7..98e6140e 100755
--- a/actions/actions.py
+++ b/actions/actions.py
@@ -16,6 +16,8 @@
 
 import os
 import sys
+import re
+
 from subprocess import (
     check_output,
     CalledProcessError,
@@ -26,6 +28,7 @@ sys.path.append('hooks/')
 from charmhelpers.core.hookenv import (
     action_fail,
     action_set,
+    action_get,
 )
 
 from rabbit_utils import (
@@ -62,9 +65,34 @@ def cluster_status(args):
         raise
 
 
+def check_queues(args):
+    """Check for queues with greater than N messages.
+    Return those queues to the user."""
+    queue_depth = (action_get('queue-depth'))
+    vhost = (action_get('vhost'))
+    result = []
+    # rabbitmqctl's output contains lines we don't want, such as
+    # 'Listing queues ..' and '...done.', which may vary by release.
+    # Actual queue results *should* always look like 'test\t0'
+    queue_pattern = re.compile('.*\t[0-9]*')
+    try:
+        queues = check_output(['rabbitmqctl', 'list_queues',
+                               '-p', vhost]).split('\n')
+        result = list({queue: size for (queue, size) in
+                       [i.split('\t') for i in queues
+                        if re.search(queue_pattern, i)]
+                       if int(size) >= queue_depth})
+
+        action_set({'output': result, 'outcome': 'Success'})
+    except CalledProcessError as e:
+        action_set({'output': e.output})
+        action_fail('Failed to run rabbitmqctl list_queues')
+
+
 # A dictionary of all the defined actions to callables (which take
 # parsed arguments).
-ACTIONS = {"pause": pause, "resume": resume, "cluster-status": cluster_status}
+ACTIONS = {"pause": pause, "resume": resume, "cluster-status": cluster_status,
+           "check-queues": check_queues}
 
 
 def main(args):
diff --git a/actions/check-queues b/actions/check-queues
new file mode 120000
index 00000000..405a394e
--- /dev/null
+++ b/actions/check-queues
@@ -0,0 +1 @@
+actions.py
\ No newline at end of file
diff --git a/tests/basic_deployment.py b/tests/basic_deployment.py
index d20f0749..a672c233 100644
--- a/tests/basic_deployment.py
+++ b/tests/basic_deployment.py
@@ -715,3 +715,10 @@ class RmqBasicDeployment(OpenStackAmuletDeployment):
         assert u.wait_on_action(action_id), "Cluster status action failed."
 
         u.log.debug('OK')
+
+    def test_912_check_queues(self):
+        """ rabbitmqctl check_queues action can be returned. """
+        u.log.debug('Checking cluster status action...')
+
+        action_id = u.run_action(self.rmq0_sentry, "check-queues")
+        assert u.wait_on_action(action_id), "Check queues action failed."
diff --git a/unit_tests/test_actions.py b/unit_tests/test_actions.py
index d1c4af5d..8a8a4baa 100644
--- a/unit_tests/test_actions.py
+++ b/unit_tests/test_actions.py
@@ -77,6 +77,40 @@ class ClusterStatusTestCase(CharmTestCase):
         self.action_fail.assert_called()
 
 
+class CheckQueuesTestCase(CharmTestCase):
+    TEST_QUEUE_RESULT = 'Listing queues ...\ntest\t0\ntest\t0\n""'
+
+    def dummy_action_get(self, key):
+        action_values = {"queue-depth": -1, "vhost": "/"}
+        return action_values[key]
+
+    def setUp(self):
+        super(CheckQueuesTestCase, self).setUp(
+            actions, ["check_output", "action_set", "action_fail",
+                      "ConfigRenderer", "action_get"])
+
+    def test_check_queues(self):
+        self.action_get.side_effect = self.dummy_action_get
+        self.check_output.return_value = self.TEST_QUEUE_RESULT
+
+        actions.check_queues([])
+        self.check_output.assert_called_once_with(['rabbitmqctl',
+                                                   'list_queues',
+                                                   '-p', "/"])
+        self.action_set.assert_called()
+
+    def test_check_queues_execption(self):
+        self.action_get.side_effect = self.dummy_action_get
+        self.check_output.return_value = self.TEST_QUEUE_RESULT
+
+        self.check_output.side_effect = actions.CalledProcessError(1,
+                                                                   "Failure")
+        actions.check_queues([])
+        self.check_output.assert_called_once_with(['rabbitmqctl',
+                                                   'list_queues',
+                                                   '-p', '/'])
+
+
 class MainTestCase(CharmTestCase):
 
     def setUp(self):