qos basic scenario

Adding a basic test to check enforcement of QoS policy with
bandwidth limit rule QoS

Spec:
http://specs.openstack.org/openstack/neutron-specs/specs/liberty/qos-api-extension.html

Change-Id: Ifb319aefeee27b3e5f1bbe16ebb99bf73f4465e7
diff --git a/neutron/tests/tempest/scenario/test_qos.py b/neutron/tests/tempest/scenario/test_qos.py
new file mode 100644
index 0000000..4a30d09
--- /dev/null
+++ b/neutron/tests/tempest/scenario/test_qos.py
@@ -0,0 +1,179 @@
+# Copyright 2016 Red Hat, Inc.
+# All Rights Reserved.
+#
+#    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 errno
+import socket
+import time
+
+from oslo_log import log as logging
+from tempest.lib.common import ssh
+from tempest.lib import exceptions
+from tempest import test
+
+from neutron.common import utils
+from neutron.tests.tempest import config
+from neutron.tests.tempest.scenario import base
+from neutron.tests.tempest.scenario import constants
+from neutron.tests.tempest.scenario import exceptions as sc_exceptions
+
+CONF = config.CONF
+LOG = logging.getLogger(__name__)
+
+
+def _try_connect(host_ip, port):
+    try:
+        client_socket = socket.socket(socket.AF_INET,
+                                      socket.SOCK_STREAM)
+        client_socket.connect((host_ip, port))
+        client_socket.setblocking(0)
+        return client_socket
+    except socket.error as serr:
+        if serr.errno == errno.ECONNREFUSED:
+            raise sc_exceptions.SocketConnectionRefused(host=host_ip,
+                                                        port=port)
+        else:
+            raise
+
+
+def _connect_socket(host, port):
+    """Try to initiate a connection to a host using an ip address
+    and a port.
+
+    Trying couple of times until a timeout is reached in case the listening
+    host is not ready yet.
+    """
+
+    start = time.time()
+    while True:
+        try:
+            return _try_connect(host, port)
+        except sc_exceptions.SocketConnectionRefused:
+            if time.time() - start > constants.SOCKET_CONNECT_TIMEOUT:
+                raise sc_exceptions.ConnectionTimeoutException(host=host,
+                                                               port=port)
+
+
+class QoSTest(base.BaseTempestTestCase):
+    credentials = ['primary', 'admin']
+    force_tenant_isolation = False
+
+    BUFFER_SIZE = 1024 * 1024
+    TOLERANCE_FACTOR = 1.5
+    BS = 512
+    COUNT = BUFFER_SIZE / BS
+    FILE_SIZE = BS * COUNT
+    LIMIT_BYTES_SEC = (constants.LIMIT_KILO_BITS_PER_SECOND * 1024
+                       * TOLERANCE_FACTOR / 8.0)
+    FILE_PATH = "/tmp/img"
+
+    def _create_file_for_bw_tests(self, ssh_client):
+        cmd = ("(dd if=/dev/zero bs=%(bs)d count=%(count)d of=%(file_path)s) "
+               % {'bs': QoSTest.BS, 'count': QoSTest.COUNT,
+               'file_path': QoSTest.FILE_PATH})
+        ssh_client.exec_command(cmd)
+        cmd = "stat -c %%s %s" % QoSTest.FILE_PATH
+        filesize = ssh_client.exec_command(cmd)
+        if int(filesize.strip()) != QoSTest.FILE_SIZE:
+            raise sc_exceptions.FileCreationFailedException(
+                file=QoSTest.FILE_PATH)
+
+    def _check_bw(self, ssh_client, host, port):
+        total_bytes_read = 0
+        cycle_start_time = time.time()
+        cycle_data_read = 0
+
+        cmd = "killall -q nc"
+        try:
+            ssh_client.exec_command(cmd)
+        except exceptions.SSHExecCommandFailed:
+            pass
+        cmd = ("(nc -ll -p %(port)d < %(file_path)s > /dev/null &)" % {
+                'port': port, 'file_path': QoSTest.FILE_PATH})
+        ssh_client.exec_command(cmd)
+        client_socket = _connect_socket(host, port)
+
+        while total_bytes_read < QoSTest.FILE_SIZE:
+            try:
+                data = client_socket.recv(QoSTest.BUFFER_SIZE)
+            except socket.error as e:
+                if e.args[0] in [errno.EAGAIN, errno.EWOULDBLOCK]:
+                    continue
+                else:
+                    raise
+            total_bytes_read += len(data)
+            cycle_data_read += len(data)
+            time_elapsed = time.time() - cycle_start_time
+            should_check = (time_elapsed >= 5 or
+                            total_bytes_read == QoSTest.FILE_SIZE)
+            if should_check:
+                LOG.debug("time_elapsed =  %(time_elapsed)d,"
+                          "total_bytes_read = %(bytes_read)d,"
+                          "cycle_data_read = %(cycle_data)d",
+                          {"time_elapsed": time_elapsed,
+                           "bytes_read": total_bytes_read,
+                           "cycle_data": cycle_data_read})
+
+                if cycle_data_read / time_elapsed > QoSTest.LIMIT_BYTES_SEC:
+                    # Limit reached
+                    return False
+                else:
+                    cycle_start_time = time.time()
+                    cycle_data_read = 0
+        return True
+
+    @test.idempotent_id('1f7ed39b-428f-410a-bd2b-db9f465680df')
+    def test_qos(self):
+        """This is a basic test that check that a QoS policy with
+
+           a bandwidth limit rule is applied correctly by sending
+           a file from the instance to the test node.
+           Then calculating the bandwidth every ~1 sec by the number of bits
+           received / elapsed time.
+        """
+
+        NC_PORT = 1234
+
+        self.setup_network_and_server()
+        self.check_connectivity(self.fip['floating_ip_address'],
+                                CONF.validation.image_ssh_user,
+                                self.keypair['private_key'])
+        rulesets = [{'protocol': 'tcp',
+                     'direction': 'ingress',
+                     'port_range_min': NC_PORT,
+                     'port_range_max': NC_PORT,
+                     'remote_ip_prefix': '0.0.0.0/0'}]
+        self.create_secgroup_rules(rulesets)
+        ssh_client = ssh.Client(self.fip['floating_ip_address'],
+                                CONF.validation.image_ssh_user,
+                                pkey=self.keypair['private_key'])
+        policy = self.admin_manager.network_client.create_qos_policy(
+                                        name='test-policy',
+                                        description='test-qos-policy',
+                                        shared=True)
+        policy_id = policy['policy']['id']
+        self.admin_manager.network_client.create_bandwidth_limit_rule(
+            policy_id, max_kbps=constants.LIMIT_KILO_BITS_PER_SECOND,
+            max_burst_kbps=constants.LIMIT_KILO_BITS_PER_SECOND)
+        port = self.client.list_ports(network_id=self.network['id'],
+                                      device_id=self.server[
+                                      'server']['id'])['ports'][0]
+        self.admin_manager.network_client.update_port(port['id'],
+                                                      qos_policy_id=policy_id)
+        self._create_file_for_bw_tests(ssh_client)
+        utils.wait_until_true(lambda: self._check_bw(
+            ssh_client,
+            self.fip['floating_ip_address'],
+            port=NC_PORT),
+            timeout=120,
+            sleep=1)