Various service detection fixes

* Move monasca-agent and extend user detection from postfix
  detection plugin to
  monasca_setup.detection.utils.get_agent_username()
* Use get_agent_username() rather than static user name in
  mon detection plugin
* Add logic for determining monasca-notification user from
  process to mon detection plugin

Change-Id: I6a00a8d6574da27274718a71fd813dedd61442b4
(cherry picked from commit f2e00f6ebc)

monasca_setup/detection/plugins/kibana.py

@@ -1,5 +1,6 @@
 # Copyright 2016 FUJITSU LIMITED
 # (C) Copyright 2016 Hewlett Packard Enterprise Development LP
+# Copyright 2017 SUSE Linux GmbH
 #
 # 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
@@ -185,11 +186,10 @@ class Kibana(detection.Plugin):
     def _has_metrics_support(self, kibana_url):
         resp = self._get_metrics_request(kibana_url, method='HEAD')
         status_code = resp.status_code
-        # although Kibana will respond with 400:Bad Request
+        # Some Kibana versions may respond with 400:Bad Request
         # it means that URL is available but simply does
         # not support HEAD request
-        # Looks like guys from Kibana just support GET for this url
+        return (status_code == 400) or (status_code == 200)
-        return status_code == 400
 
     def _get_metrics_request(self, url, method='GET'):
         request_url = '%s/%s' % (url, _API_STATUS)

monasca_setup/detection/plugins/libvirt.py

@@ -1,4 +1,5 @@
 # (c) Copyright 2015-2016 Hewlett Packard Enterprise Development LP
+# Copyright 2017 SUSE Linux GmbH
 
 import ConfigParser
 import grp
@@ -12,6 +13,7 @@ import sys
 from monasca_agent.common.psutil_wrapper import psutil
 import monasca_setup.agent_config
 from monasca_setup.detection import Plugin
+from monasca_setup.detection import utils
 
 
 log = logging.getLogger(__name__)
@@ -53,12 +55,7 @@ class Libvirt(Plugin):
     def _detect(self):
         """Set self.available True if the process and config file are detected
         """
-        # Detect Agent's OS username by getting the group owner of confg file
+        self.agent_user = utils.get_agent_username()
-        try:
-            gid = os.stat('/etc/monasca/agent/agent.yaml').st_gid
-            self.agent_user = grp.getgrgid(gid)[0]
-        except OSError:
-            self.agent_user = None
         # Try to detect the location of the Nova configuration file.
         # Walk through the list of processes, searching for 'nova-compute'
         # process with 'nova.conf' inside one of the parameters

monasca_setup/detection/plugins/mon.py

@@ -1,5 +1,6 @@
 # (C) Copyright 2015-2016 Hewlett Packard Enterprise Development LP
 # Copyright 2016 FUJITSU LIMITED
+# Copyright 2017 SUSE Linux GmbH
 
 """Classes for monitoring the monitoring server stack.
 
@@ -18,6 +19,7 @@ import monasca_setup.agent_config
 import monasca_setup.detection
 from monasca_setup.detection import find_process_cmdline
 from monasca_setup.detection import find_process_name
+from monasca_setup.detection.utils import get_agent_username
 from monasca_setup.detection.utils import watch_process
 from monasca_setup.detection.utils import watch_process_by_username
 
@@ -72,8 +74,8 @@ class MonAgent(monasca_setup.detection.Plugin):
     def build_config(self):
         """Build the config as a Plugins object and return."""
         log.info("\tEnabling the Monasca Agent process check")
-        return watch_process_by_username('mon-agent', 'monasca-agent', 'monitoring',
+        return watch_process_by_username(get_agent_username(), 'monasca-agent',
-                                         'monasca-agent')
+                                         'monitoring', 'monasca-agent')
 
     def dependencies_installed(self):
         return True
@@ -197,8 +199,10 @@ class MonNotification(monasca_setup.detection.Plugin):
     def build_config(self):
         """Build the config as a Plugins object and return."""
         log.info("\tEnabling the Monasca Notification healthcheck")
-        return watch_process_by_username('mon-notification', 'monasca-notification', 'monitoring',
+        notification_process = find_process_cmdline('monasca-notification')
-                                         'monasca-notification')
+        notification_user = notification_process.as_dict(['username'])['username']
+        return watch_process_by_username(notification_user, 'monasca-notification',
+                                         'monitoring', 'monasca-notification')
 
     def dependencies_installed(self):
         return True

monasca_setup/detection/plugins/postfix.py

@@ -1,9 +1,9 @@
 # (c) Copyright 2015-2016 Hewlett Packard Enterprise Development LP
 # Copyright 2017 Fujitsu LIMITED
+# Copyright 2017 SUSE Linux GmbH
 
 import logging
 import os
-import pwd
 import yaml
 
 from monasca_setup import agent_config
@@ -34,7 +34,7 @@ class Postfix(plugin.Plugin):
         try:
             has_process = (utils.find_process_cmdline(_POSTFIX_PROC_NAME)
                            is not None)
-            agent_user = self._get_agent_username() if has_process else None
+            agent_user = utils.get_agent_username() if has_process else None
             has_user = agent_user is not None
             has_sudoers = (self._has_sudoers(agent_user)
                            if agent_user else False)
@@ -75,12 +75,6 @@ class Postfix(plugin.Plugin):
     def dependencies_installed(self):
         return True
 
-    @staticmethod
-    def _get_agent_username():
-        uid = os.stat('/etc/monasca/agent/agent.yaml').st_uid
-        agent_user = pwd.getpwuid(uid).pw_name
-        return agent_user
-
     @staticmethod
     def _has_sudoers(agent_user):
         test_sudo = os.system(_POSTFIX_CHECK_COMMAND.format(agent_user))

monasca_setup/detection/utils.py

@@ -1,8 +1,11 @@
 # (C) Copyright 2015-2016 Hewlett Packard Enterprise Development LP
+# Copyright 2017 SUSE Linux GmbH
 
 """ Util functions to assist in detection.
 """
 import logging
+import os
+import pwd
 import subprocess
 from subprocess import CalledProcessError
 from subprocess import PIPE
@@ -13,6 +16,8 @@ from monasca_setup import agent_config
 
 log = logging.getLogger(__name__)
 
+_DEFAULT_AGENT_USER = 'mon-agent'
+_DETECTED_AGENT_USER = None
 
 # check_output was introduced in python 2.7, function added
 # to accommodate python 2.6
@@ -93,6 +98,39 @@ def find_addr_listening_on_port_over_tcp(port):
         return ip[0].lstrip("::ffff:")
 
 
+def get_agent_username():
+    """Determine the user monasca-agent runs as"""
+
+    global _DETECTED_AGENT_USER
+
+    # Use cached agent user in subsequent calls
+    if _DETECTED_AGENT_USER is not None:
+        return _DETECTED_AGENT_USER
+
+    # Try the owner of agent.yaml first
+    try:
+        uid = os.stat('/etc/monasca/agent/agent.yaml').st_uid
+    except OSError:
+        uid = None
+
+    if uid is not None:
+        _DETECTED_AGENT_USER = pwd.getpwuid(uid).pw_name
+        return _DETECTED_AGENT_USER
+
+    # No agent.yaml, so try to find a running monasca-agent process
+    agent_process = find_process_name('monasca-agent')
+
+    if agent_process is not None:
+        _DETECTED_AGENT_USER = agent_process.username()
+        return _DETECTED_AGENT_USER
+
+    # Fall back to static agent user
+    log.warn("Could not determine monasca-agent service user, falling "
+             "back to %s" % _DEFAULT_AGENT_USER)
+    _DETECTED_AGENT_USER = _DEFAULT_AGENT_USER
+    return _DETECTED_AGENT_USER
+
+
 def watch_process(search_strings, service=None, component=None,
                   exact_match=True, detailed=True, process_name=None):
     """Takes a list of process search strings and returns a Plugins object with the config set.