promise/plugin: add check_network promise

slapos/promise/plugin/check_network.py

+import psutil
+
+from zope.interface import implementer
+from slapos.grid.promise import interface
+from slapos.grid.promise.generic import GenericPromise
+
+@implementer(interface.IPromise)
+class RunPromise(GenericPromise):
+
+  def __init__(self, config):
+
+    super(RunPromise, self).__init__(config)
+    self.setPeriodicity(minute=5)
+
+
+  def sense(self):
+
+    promise_success = True
+    
+    # Get reference values
+    max_lost_packets = int(self.getConfig('max-lost-packets', 100))
+    max_error_messages = int(self.getConfig('max-error-messages', 100))
+
+    # Get current Network statistics
+    network_data =  psutil.net_io_counters() # Check for args if useful
+    total_dropped = network_data.dropin + network_data.dropout
+    total_errors = network_data.errin + network_data.errout
+
+    # Check for network dropped packets
+    if total_dropped >= max_lost_packets:
+      self.logger.error("Network packets lost reached critical threshold: %s "\
+        " (threshold is %s)" % (total_dropped, max_lost_packets))
+      promise_success = False
+
+    # Check for network errors
+    if total_errors >= max_error_messages:
+      self.logger.error("Network errors reached critical threshold: %s "\
+        " (threshold is %s)" % (total_errors, max_error_messages))
+      promise_success = False
+
+    if promise_success:
+      self.logger.info("Network statistics OK")
+
+  def test(self):
+    """
+    Called after sense() if the instance is still converging.
+    Returns success or failure based on sense results.
+
+    In this case, fail if the previous sensor result is negative.
+    """
+    return self._test(result_count=1, failure_amount=1)
+
+
+  def anomaly(self):
+    """
+    Called after sense() if the instance has finished converging.
+    Returns success or failure based on sense results.
+    Failure signals the instance has diverged.
+
+    In this case, fail if two out of the last three results are negative.
+    """
+    return self._anomaly(result_count=3, failure_amount=2)

slapos/test/promise/plugin/test_check_network.py

+# -*- coding: utf-8 -*-
+##############################################################################
+# Copyright (c) 2022 Vifib SARL and Contributors. All Rights Reserved.
+#
+# WARNING: This program as such is intended to be used by professional
+# programmers who take the whole responsibility of assessing all potential
+# consequences resulting from its eventual inadequacies and bugs
+# End users who are looking for a ready-to-use solution with commercial
+# guarantees and support are strongly advised to contract a Free Software
+# Service Company
+#
+# This program is Free Software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+##############################################################################
+import mock
+
+from collections import namedtuple
+from slapos.grid.promise import PromiseError
+from slapos.promise.plugin.check_network import RunPromise
+from . import TestPromisePluginMixin
+
+
+class TestCheckNetwork(TestPromisePluginMixin):
+
+  promise_name = "monitor-network.py"
+
+  def setUp(self):
+    super(TestCheckNetwork, self).setUp()
+
+  def writePromise(self, **kw):
+    super(TestCheckNetwork, self).writePromise(self.promise_name,
+      "from %s import %s\nextra_config_dict = %r\n"
+      % (RunPromise.__module__, RunPromise.__name__, kw))
+
+  def runPromise(self, summary, failed=False):
+    self.configureLauncher(enable_anomaly=True, force=True)
+    with mock.patch('psutil.net_io_counters', return_value=summary):
+      if failed:
+        self.assertRaises(PromiseError, self.launcher.run)
+      else:
+        self.launcher.run()
+    result = self.getPromiseResult(self.promise_name)['result']
+    self.assertEqual(result['failed'], failed)
+    return result['message']
+
+  def test_network_ok(self):
+    message = "Network statistics OK"
+    network_data = namedtuple('network_data', ['errin', 'errout', 'dropin', 'dropout'])
+    mock_stats = {'errin':0, 'errout':0, 'dropin':0, 'dropout':0}
+    self.writePromise(**{
+        'max-lost-packets': 5,
+        'max-error-messages': 5,
+    })
+    self.assertEqual(message, self.runPromise(network_data(**mock_stats)))
+
+  def test_network_dropped_packets_nok(self):
+    message = "Network packets lost reached critical threshold: 10  (threshold is 5)"
+    network_data = namedtuple('network_data', ['errin', 'errout', 'dropin', 'dropout'])
+    mock_stats = {'errin':0, 'errout':0, 'dropin':5, 'dropout':5}
+    self.writePromise(**{
+        'max-lost-packets': 5,
+        'max-error-messages': 5,
+    })
+    self.assertEqual(message, self.runPromise(network_data(**mock_stats)))
+
+  def test_network_errors_nok(self):
+    message = "Network errors reached critical threshold: 10  (threshold is 5)"
+    network_data = namedtuple('network_data', ['errin', 'errout', 'dropin', 'dropout'])
+    mock_stats = {'errin':5, 'errout':5, 'dropin':0, 'dropout':0}
+    self.writePromise(**{
+        'max-lost-packets': 5,
+        'max-error-messages': 5,
+    })
+    self.assertEqual(message, self.runPromise(network_data(**mock_stats)))
+
+  def test_network_nok(self):
+    message = "Network packets lost reached critical threshold: 10  (threshold is 5)"\
+      "\nNetwork errors reached critical threshold: 10  (threshold is 5)"
+    network_data = namedtuple('network_data', ['errin', 'errout', 'dropin', 'dropout'])
+    mock_stats = {'errin':5, 'errout':5, 'dropin':5, 'dropout':5}
+    self.writePromise(**{
+        'max-lost-packets': 5,
+        'max-error-messages': 5,
+    })
+    self.assertEqual(message, self.runPromise(network_data(**mock_stats)))
+
+if __name__ == '__main__':
+  unittest.main()