Replace six.iteritems/itervalues with dict.items()/values()

1.As mentioned in [1], we should avoid using six.iteritems
to achieve iterators. We can use dict.items instead, as it will
return iterators in PY3 as well. And dict.items/keys will more
readable.
2.In py2, the performance about list should be negligible,
see the link [2].
[1] https://wiki.openstack.org/wiki/Python3
[2] http://lists.openstack.org/pipermail/openstack-dev/2015-June/066391.html

Change-Id: I1d260757c26449317e34367141bdbcfec7831647

dragonflow/cli/utils.py

@@ -86,7 +86,7 @@ def keys_and_vals_to_strs(dictionary):
             return str(k_or_v)
         else:
             return k_or_v
-    return dict((to_str(k), to_str(v)) for k, v in six.iteritems(dictionary))
+    return dict((to_str(k), to_str(v)) for k, v in dictionary.items())
 
 
 def _format_field_name(attr):
@@ -135,7 +135,7 @@ def print_dict(dct, dict_property="Property", wrap=0):
     """
     pt = prettytable.PrettyTable([dict_property, 'Value'])
     pt.align = 'l'
-    for k, v in six.iteritems(dct):
+    for k, v in dct.items():
         # convert dict to str to check length
         if isinstance(v, dict):
             v = six.text_type(keys_and_vals_to_strs(v))

dragonflow/controller/dnat_app.py

@@ -18,7 +18,6 @@ import collections
 import netaddr
 from neutron_lib import constants as n_const
 from ryu.ofproto import ether
-import six
 
 from dragonflow import conf as cfg
 from dragonflow.controller.common import arp_responder
@@ -58,7 +57,7 @@ class DNATApp(df_base_app.DFlowApp):
                 or mac == '00:00:00:00:00:00'):
             return
 
-        for key, floatingip in six.iteritems(self.local_floatingips):
+        for key, floatingip in self.local_floatingips.items():
             self._install_dnat_egress_rules(floatingip, mac)
             self.update_floatingip_status(
                 floatingip, n_const.FLOATINGIP_STATUS_ACTIVE)
@@ -87,7 +86,7 @@ class DNATApp(df_base_app.DFlowApp):
     def _is_first_external_network(self, network_id):
         if self._get_external_network_count(network_id) == 0:
             # check whether there are other networks
-            for key, val in six.iteritems(self.external_networks):
+            for key, val in self.external_networks.items():
                 if key != network_id and val > 0:
                     return False
             return True
@@ -96,7 +95,7 @@ class DNATApp(df_base_app.DFlowApp):
     def _is_last_external_network(self, network_id):
         if self._get_external_network_count(network_id) == 1:
             # check whether there are other networks
-            for key, val in six.iteritems(self.external_networks):
+            for key, val in self.external_networks.items():
                 if key != network_id and val > 0:
                     return False
             return True
@@ -308,7 +307,7 @@ class DNATApp(df_base_app.DFlowApp):
     def remove_local_port(self, lport):
         port_id = lport.get_id()
         ips_to_disassociate = [
-            fip for fip in six.itervalues(self.local_floatingips)
+            fip for fip in self.local_floatingips.values()
             if fip.get_lport_id() == port_id]
         for floatingip in ips_to_disassociate:
             self.disassociate_floatingip(floatingip)

dragonflow/controller/l2_app.py

@@ -22,7 +22,6 @@ from oslo_log import log
 from ryu.lib.mac import haddr_to_bin
 from ryu.lib.packet import in_proto
 from ryu.ofproto import ether
-import six
 
 from dragonflow._i18n import _, _LI, _LE
 from dragonflow import conf as cfg
@@ -75,7 +74,7 @@ class L2App(df_base_app.DFlowApp):
 
         :param bridge_mappings: map physical network names to bridge names.
         '''
-        for physical_network, bridge in six.iteritems(bridge_mappings):
+        for physical_network, bridge in bridge_mappings.items():
             LOG.info(_LI("Mapping physical network %(physical_network)s to "
                          "bridge %(bridge)s"),
                      {'physical_network': physical_network,

dragonflow/controller/sg_app.py

@@ -17,7 +17,6 @@ import netaddr
 from neutron_lib import constants as n_const
 from oslo_log import log
 from ryu.ofproto import ether
-import six
 
 from dragonflow._i18n import _LI, _LW, _LE
 from dragonflow.controller.common import constants as const
@@ -792,7 +791,7 @@ class SGApp(df_base_app.DFlowApp):
         # of remote group.
         secrules = self.remote_secgroup_ref.get(secgroup_id)
         if secrules:
-            for rule_info in six.itervalues(secrules):
+            for rule_info in secrules.values():
                 self._update_security_group_rule_flows_by_addresses(
                     rule_info.get_security_group_id(),
                     rule_info,
@@ -822,7 +821,7 @@ class SGApp(df_base_app.DFlowApp):
             # parameter of remote group.
             secrules = self.remote_secgroup_ref.get(secgroup_id)
             if secrules:
-                for rule_info in six.itervalues(secrules):
+                for rule_info in secrules.values():
                     self._update_security_group_rule_flows_by_addresses(
                         rule_info.get_security_group_id(),
                         rule_info,

dragonflow/controller/topology.py

@@ -12,7 +12,6 @@
 
 from oslo_config import cfg
 from oslo_log import log
-import six
 
 from dragonflow._i18n import _LI, _LE, _LW
 from dragonflow.common import constants
@@ -301,7 +300,7 @@ class Topology(object):
         new_ovs_to_lport_mapping = {}
         add_ovs_to_lport_mapping = {}
         delete_ovs_to_lport_mapping = self.ovs_to_lport_mapping
-        for key, ovs_port in six.iteritems(self.ovs_ports):
+        for key, ovs_port in self.ovs_ports.items():
             if ovs_port.get_type() == db_models.OvsPort.TYPE_VM:
                 lport_id = ovs_port.get_iface_id()
                 lport = self._get_lport(lport_id)

dragonflow/db/db_store.py

@@ -17,8 +17,6 @@ import collections
 import copy
 import threading
 
-import six
-
 from dragonflow.db import models
 
 
@@ -93,7 +91,7 @@ class DbStore(object):
     def get(self, table_name, key, topic):
         if topic:
             return self.tenant_dbs[topic].get(table_name, key)
-        for tenant_db in six.itervalues(self.tenant_dbs):
+        for tenant_db in self.tenant_dbs.values():
             value = tenant_db.get(table_name, key)
             if value:
                 return value
@@ -102,7 +100,7 @@ class DbStore(object):
         if topic:
             return self.tenant_dbs[topic].keys(table_name)
         result = []
-        for tenant_db in six.itervalues(self.tenant_dbs):
+        for tenant_db in self.tenant_dbs.values():
             result.extend(tenant_db.keys(table_name))
         return result
 
@@ -110,7 +108,7 @@ class DbStore(object):
         if topic:
             return self.tenant_dbs[topic].values(table_name)
         result = []
-        for tenant_db in six.itervalues(self.tenant_dbs):
+        for tenant_db in self.tenant_dbs.values():
             result.extend(tenant_db.values(table_name))
         return result
 
@@ -123,7 +121,7 @@ class DbStore(object):
         if topic:
             self.tenant_dbs[topic].pop(table_name, key)
         else:
-            for tenant_db in six.itervalues(self.tenant_dbs):
+            for tenant_db in self.tenant_dbs.values():
                 if tenant_db.pop(table_name, key):
                     break
 
@@ -362,7 +360,7 @@ class DbStore(object):
 
     def clear(self, topic=None):
         if not topic:
-            for tenant_db in six.itervalues(self.tenant_dbs):
+            for tenant_db in self.tenant_dbs.values():
                 tenant_db.clear()
         else:
             self.tenant_dbs[topic].clear()

dragonflow/db/drivers/redis_db_driver.py

@@ -15,7 +15,6 @@ import re
 from oslo_log import log
 from redis import client as redis_client
 from redis import exceptions
-import six
 
 from dragonflow._i18n import _LE, _LW
 from dragonflow.db import db_api
@@ -59,7 +58,7 @@ class RedisDbDriver(db_api.DbApi):
 
     def delete_table(self, table):
         local_key = self._uuid_to_key(table, '*', '*')
-        for host, client in six.iteritems(self.clients):
+        for host, client in self.clients.items():
             local_keys = client.keys(local_key)
             if len(local_keys) > 0:
                 for tmp_key in local_keys:
@@ -178,7 +177,7 @@ class RedisDbDriver(db_api.DbApi):
             local_key = self._uuid_to_key(table, key, '*')
             self._sync_master_list()
             try:
-                for host, client in six.iteritems(self.clients):
+                for host, client in self.clients.items():
                     local_keys = client.keys(local_key)
                     if len(local_keys) == 1:
                         return self._execute_cmd("GET", local_keys[0])
@@ -232,7 +231,7 @@ class RedisDbDriver(db_api.DbApi):
         if not topic:
             local_key = self._uuid_to_key(table, '*', '*')
             try:
-                for host, client in six.iteritems(self.clients):
+                for host, client in self.clients.items():
                     local_keys = client.keys(local_key)
                     if len(local_keys) > 0:
                         for tmp_key in local_keys:
@@ -267,7 +266,7 @@ class RedisDbDriver(db_api.DbApi):
         if not topic:
             local_key = self._uuid_to_key(table, '*', '*')
             try:
-                for host, client in six.iteritems(self.clients):
+                for host, client in self.clients.items():
                     ip_port = host
                     res.extend(client.keys(local_key))
                 return [self._strip_table_name_from_key(key) for key in res]

dragonflow/db/drivers/redis_mgt.py

@@ -126,7 +126,7 @@ class RedisMgt(object):
     def get_cluster_topology_by_all_nodes(self):
         # get redis cluster topology from local nodes cached in initialization
         new_nodes = {}
-        for host, info in six.iteritems(self.cluster_nodes):
+        for host, info in self.cluster_nodes.items():
             ip_port = host.split(':')
             try:
                 node = self._init_node(ip_port[0], ip_port[1])
@@ -218,7 +218,7 @@ class RedisMgt(object):
 
     def _parse_to_masterlist(self):
         master_list = []
-        for host, info in six.iteritems(self.cluster_nodes):
+        for host, info in self.cluster_nodes.items():
             if 'master' == info['role']:
                 slots = []
                 if len(info['slots']) > 0:
@@ -269,8 +269,8 @@ class RedisMgt(object):
             slave_cnt = 0
             slot_changed = False
 
-            for host, info in six.iteritems(old_nodes):
-                for new_host, new_info in six.iteritems(new_nodes):
+            for host, info in old_nodes.items():
+                for new_host, new_info in new_nodes.items():
                     if host == new_host and info['role'] == \
                             new_info['role']:
                         if info['slots'] != new_info['slots']:

dragonflow/db/drivers/zookeeper_db_driver.py

@@ -32,7 +32,7 @@ def _parse_hosts(hosts):
         return hosts.strip()
     if isinstance(hosts, (dict)):
         host_ports = []
-        for (k, v) in six.iteritems(hosts):
+        for (k, v) in hosts.items():
             host_ports.append("%s:%s" % (k, v))
         hosts = host_ports
     if isinstance(hosts, (list, set, tuple)):

dragonflow/ovsdb/commands.py

@@ -10,8 +10,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import six
-
 from neutron.agent.ovsdb.native import commands
 from neutron.agent.ovsdb.native import idlutils
 from oslo_config import cfg
@@ -138,7 +136,7 @@ class DeleteQos(commands.BaseCommand):
         conditions = [('external_ids', '=', {'iface-id': self.port_id})]
         rows_to_delete = []
         for table in ['QoS', 'Queue']:
-            for r in six.itervalues(self.api._tables[table].rows):
+            for r in self.api._tables[table].rows.values():
                 if idlutils.row_match(r, conditions):
                     rows_to_delete.append(r)
 
@@ -155,7 +153,7 @@ class UpdateQos(commands.BaseCommand):
     def run_idl(self, txn):
         conditions = [('external_ids', '=', {'iface-id': self.port_id})]
         queue_table = self.api._tables['Queue']
-        for r in six.itervalues(queue_table.rows):
+        for r in queue_table.rows.values():
             if idlutils.row_match(r, conditions):
                 dscp = self.qos.get_dscp_marking()
                 dscp = dscp if dscp else []
@@ -169,7 +167,7 @@ class UpdateQos(commands.BaseCommand):
                 setattr(r, 'other_config', other_config)
 
         qos_table = self.api._tables['QoS']
-        for r in six.itervalues(qos_table.rows):
+        for r in qos_table.rows.values():
             if idlutils.row_match(r, conditions):
                 external_ids = getattr(r, 'external_ids', {})
                 external_ids['version'] = str(self.qos.get_version())

dragonflow/ovsdb/impl_idl.py

@@ -16,7 +16,6 @@ from neutron.agent.ovsdb import impl_idl
 from neutron.agent.ovsdb.native import connection
 from oslo_config import cfg
 from ovs.db import idl
-import six
 
 from dragonflow.common import constants
 from dragonflow.ovsdb import commands
@@ -108,7 +107,7 @@ class DFConnection(connection.Connection):
     """
     def update_schema_helper(self, helper):
         tables = ovsdb_monitor_table_filter_default
-        for table_name, columns in six.iteritems(tables):
+        for table_name, columns in tables.items():
             if columns == 'all':
                 helper.register_table(table_name)
             else:

dragonflow/tests/fullstack/test_objects.py

@@ -11,7 +11,6 @@
 #    under the License.
 
 import netaddr
-import six
 import time
 
 from neutronclient.common import exceptions
@@ -287,7 +286,7 @@ class VMTestObj(object):
         if self.server is None:
             return None
         ips = self.nova.servers.ips(self.server)
-        for id, network in six.iteritems(ips):
+        for id, network in ips.items():
             for ip in network:
                 if int(ip['version']) == 4:
                     return ip['addr']