Add support to check Apache

This patch adds the collectd plugin to check Apache and it also adds
a new alarm.

Change-Id: I70dc85dae2de7e7afa1d2a046c96071d242a60b1

deployment_scripts/puppet/modules/fuel_lma_collector/templates/alarming.yaml.erb

@@ -330,6 +330,18 @@ lma_collector:
             window: 60
             periods: 0
             function: min
+    - name: 'apache-check'
+      description: 'Apache cannot be checked'
+      severity: 'down'
+      enabled: 'true'
+      trigger:
+        rules:
+          - metric: apache_check
+            relational_operator: '=='
+            threshold: 0
+            window: 60
+            periods: 0
+            function: last
     - name: 'log-fs-warning'
       description: "The log filesystem's free space is low"
       severity: 'warning'
@@ -1136,6 +1148,7 @@ lma_collector:
       check: ['mysql-check']
     apache:
       worker: ['apache-warning']
+      check: ['apache-check']
     nova-api:
       http_errors: ['nova-api-http-errors']
     nova-logs:

deployment_scripts/puppet/modules/fuel_lma_collector/templates/gse_filters.yaml.erb

@@ -167,6 +167,7 @@ lma_collector:
         group_by: hostname
         members:
           - worker
+          - check
       memcached-service:
         policy: majority_of_members
         group_by: hostname

deployment_scripts/puppet/modules/lma_collector/files/collectd/collectd_apache_check.py

@@ -0,0 +1,66 @@
+#!/usr/bin/python
+# Copyright 2016 Mirantis, Inc.
+#
+# 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.
+
+import collectd
+import collectd_base as base
+import requests
+
+NAME = 'apache'
+
+
+class ApacheCheckPlugin(base.Base):
+
+    def __init__(self, *args, **kwargs):
+        super(ApacheCheckPlugin, self).__init__(*args, **kwargs)
+        self.plugin = NAME
+        self.url = None
+
+    def config_callback(self, conf):
+        super(ApacheCheckPlugin, self).config_callback(conf)
+
+        for node in conf.children:
+            if node.key == 'Url':
+                self.url = node.values[0]
+
+        if self.url is None:
+            self.logger.error("{}: Missing Url parameter".format(NAME))
+
+    def read_callback(self):
+        try:
+            requests.get(self.url, timeout=5)
+            self.dispatch_check_metric(self.OK)
+        except Exception as err:
+            msg = "{}: Failed to check service: {}".format(NAME, err)
+            self.logger.error(msg)
+            self.dispatch_check_metric(self.FAIL, msg)
+
+
+plugin = ApacheCheckPlugin(collectd)
+
+
+def init_callback():
+    plugin.restore_sigchld()
+
+
+def config_callback(conf):
+    plugin.config_callback(conf)
+
+
+def read_callback():
+    plugin.read_callback()
+
+collectd.register_init(init_callback)
+collectd.register_config(config_callback)
+collectd.register_read(read_callback)

deployment_scripts/puppet/modules/lma_collector/manifests/collectd/apache.pp

@@ -18,12 +18,19 @@ class lma_collector::collectd::apache (
   $port = $lma_collector::params::apache_status_port,
 ) inherits lma_collector::params {
 
+  $apache_url = "http://${host}:${port}/server-status?auto"
+
   class { 'collectd::plugin::apache':
     instances => {
       'localhost' => {
-        'url' => "http://${host}:${port}/server-status?auto"
+        'url' => $apache_url,
       },
     }
   }
 
+  lma_collector::collectd::python {'collectd_apache_check':
+    config => {
+      'Url' => "\"${apache_url}\"",
+    },
+  }
 }

deployment_scripts/puppet/modules/lma_collector/spec/classes/lma_collector_collectd_apache_spec.rb

@@ -25,7 +25,11 @@ describe 'lma_collector::collectd::apache' do
 
     describe 'with "host" and "port" param' do
         let(:params) {{:host => 'example.com', :port => '8081'}}
-        it { is_expected.to contain_class('collectd::plugin::apache') \
-             .with_instances({'localhost' => {'url' => 'http://example.com:8081/server-status?auto'}}) }
+        it {
+            is_expected.to contain_class('collectd::plugin::apache') \
+             .with_instances({'localhost' => {'url' => 'http://example.com:8081/server-status?auto'}})
+            is_expected.to contain_lma_collector__collectd__python('collectd_apache_check') \
+             .with_config({'Url' => "\"http://example.com:8081/server-status?auto\""})
+        }
     end
 end