Fix timezone awareness for Python 2.7.x

The datetime module doesn't provide timezone.utc under Python 2.7.x, so
define it for ourselves.

isc_dhcp_leases/iscdhcpleases.py

@@ -8,6 +8,27 @@
 from six import iteritems
 
 
+try:
+    utc = datetime.timezone.utc
+except:
+    # Support Python 2.7
+    class UTC(datetime.tzinfo):
+        def fromutc(self, dt):
+            return dt
+
+        def utcffset(self, dt):
+            return datetime.timedelta(0)
+
+        def dst(self, dt):
+            return None
+
+        def tzname(self, dt):
+            return 'UTC'
+
+
+    utc = UTC()
+
+
 def check_datetime(dt):
     if not (dt is None or (isinstance(dt, datetime.datetime) and dt.tzinfo)):
         raise ValueError('None or offset-aware datetime required')
@@ -27,7 +48,7 @@ def parse_time(s):
         hour, minute, sec = time_part.split(':')
         result = datetime.datetime(*map(int, (year, mon, day, hour, minute, sec)))
 
-    return result.replace(tzinfo=datetime.timezone.utc)
+    return result.replace(tzinfo=utc)
 
 
 def _extract_prop_option(line):
@@ -216,7 +237,7 @@ def now(self):
         if self._now:
             return self._now
         else:
-            return datetime.datetime.utcnow().replace(tzinfo=datetime.timezone.utc)
+            return datetime.datetime.utcnow().replace(tzinfo=utc)
 
 class Lease(BaseLease):
     """

isc_dhcp_leases/test_iscDhcpLeases.py

@@ -1,6 +1,6 @@
 import datetime
 from unittest import TestCase
-from isc_dhcp_leases.iscdhcpleases import IscDhcpLeases, Lease, Lease6
+from isc_dhcp_leases.iscdhcpleases import IscDhcpLeases, Lease, Lease6, utc
 from freezegun import freeze_time
 
 __author__ = 'Martijn Braam <martijn@brixit.nl>'
@@ -9,7 +9,7 @@
 class TestIscDhcpLeases(TestCase):
     def _test_get(self, now=None):
         leases = IscDhcpLeases("isc_dhcp_leases/test_files/debian7.leases", now=now)
-        lease_start = datetime.datetime(2013, 12, 10, 12, 57, 4, tzinfo=datetime.timezone.utc)
+        lease_start = datetime.datetime(2013, 12, 10, 12, 57, 4, tzinfo=utc)
         lease_end = lease_start + datetime.timedelta(minutes=10)
         result = leases.get()
         self.assertEqual(len(result), 5)
@@ -25,7 +25,7 @@ def _test_get(self, now=None):
         self.assertEqual(result[0].sets, {'vendor-class-identifier': 'Some Vendor Identifier'})
 
         leases = IscDhcpLeases("isc_dhcp_leases/test_files/pfsense.leases", now=now)
-        lease_start = datetime.datetime(2015, 7, 6, 7, 50, 42, tzinfo=datetime.timezone.utc)
+        lease_start = datetime.datetime(2015, 7, 6, 7, 50, 42, tzinfo=utc)
         lease_end = lease_start + datetime.timedelta(minutes=30)
         result = leases.get()
         self.assertEqual(len(result), 2)
@@ -53,7 +53,7 @@ def _test_get(self, now=None):
         self.assertEqual(result[0].max_life, 600)
         self.assertEqual(
             result[0].last_communication,
-            datetime.datetime(2015, 8, 18, 16, 55, 37, tzinfo=datetime.timezone.utc))
+            datetime.datetime(2015, 8, 18, 16, 55, 37, tzinfo=utc))
         self.assertEqual(result[0].type, Lease6.NON_TEMPORARY)
 
         self.assertEqual(result[1].ip, "2001:610:500:fff::/64")
@@ -67,7 +67,7 @@ def _test_get(self, now=None):
         self.assertEqual(result[1].max_life, 200)
         self.assertEqual(
             result[1].last_communication,
-            datetime.datetime(2015, 8, 18, 16, 55, 40, tzinfo=datetime.timezone.utc))
+            datetime.datetime(2015, 8, 18, 16, 55, 40, tzinfo=utc))
         self.assertEqual(result[1].type, Lease6.PREFIX_DELEGATION)
 
         leases = IscDhcpLeases("isc_dhcp_leases/test_files/dhcpd6-4.3.3.leases", now=now)
@@ -84,7 +84,7 @@ def _test_get(self, now=None):
         self.assertEqual(result[0].max_life, 864)
         self.assertEqual(
             result[0].last_communication,
-            datetime.datetime(2016, 1, 6, 14, 50, 34, tzinfo=datetime.timezone.utc))
+            datetime.datetime(2016, 1, 6, 14, 50, 34, tzinfo=utc))
         self.assertEqual(result[0].type, Lease6.NON_TEMPORARY)
         self.assertEqual(result[0].sets, dict(iana='2001:10:10:0:0:0:0:106', clientduid='0100011cf710a5002722332b34'))
 
@@ -99,14 +99,14 @@ def _test_get(self, now=None):
         self.assertEqual(result[1].max_life, 864)
         self.assertEqual(
             result[1].last_communication,
-            datetime.datetime(2016, 1, 6, 14, 52, 37, tzinfo=datetime.timezone.utc))
+            datetime.datetime(2016, 1, 6, 14, 52, 37, tzinfo=utc))
         self.assertEqual(result[1].type, Lease6.PREFIX_DELEGATION)
         self.assertEqual(result[1].sets, dict(iapd='2001:10:30:ff00:0:0:0:0', pdsize='56',
                                               pdnet='2001:10:30:ff00:0:0:0:0/56',
                                               clientduid='0100011d344c000025906ba134'))
 
         leases = IscDhcpLeases("isc_dhcp_leases/test_files/options.leases", now=now)
-        lease_start = datetime.datetime(2016, 2, 27, 7, 11, 41, tzinfo=datetime.timezone.utc)
+        lease_start = datetime.datetime(2016, 2, 27, 7, 11, 41, tzinfo=utc)
         lease_end = lease_start + datetime.timedelta(hours=2)
         result = leases.get()
         self.assertEqual(len(result), 1)
@@ -127,7 +127,7 @@ def _test_get(self, now=None):
                               'agent.unknown-9': '0:0:11:8b:6:1:4:1:2:3:0'})
 
         leases = IscDhcpLeases("isc_dhcp_leases/test_files/static.leases", now=now)
-        lease_start = datetime.datetime(2015, 9, 10, 0, 29, 0, tzinfo=datetime.timezone.utc)
+        lease_start = datetime.datetime(2015, 9, 10, 0, 29, 0, tzinfo=utc)
         lease_end = None
         result = leases.get()
         self.assertEqual(len(result), 1)
@@ -145,17 +145,17 @@ def test_get_frozen(self):
 
     def test_get_historical(self):
         self._test_get(
-            now=datetime.datetime(2015, 7, 6, 8, 15, 0, tzinfo=datetime.timezone.utc))
+            now=datetime.datetime(2015, 7, 6, 8, 15, 0, tzinfo=utc))
 
     @freeze_time("2015-06-6 8:15:0")
     def test_backup_leases(self):
         leases = IscDhcpLeases("isc_dhcp_leases/test_files/backup.leases")
         lease_start = [
-            datetime.datetime(2017, 10, 5, 15, 22, 29, tzinfo=datetime.timezone.utc),
-            datetime.datetime(2017, 10, 10, 12, 5, 14, tzinfo=datetime.timezone.utc),
+            datetime.datetime(2017, 10, 5, 15, 22, 29, tzinfo=utc),
+            datetime.datetime(2017, 10, 10, 12, 5, 14, tzinfo=utc),
         ]
         lease_end = [
-            datetime.datetime(2017, 10, 16, 8, 9, 23, tzinfo=datetime.timezone.utc),
+            datetime.datetime(2017, 10, 16, 8, 9, 23, tzinfo=utc),
             None,
         ]
         result = leases.get()
@@ -181,11 +181,11 @@ def test_backup_leases(self):
     def test_epoch_leases(self):
         leases = IscDhcpLeases("isc_dhcp_leases/test_files/epoch.leases")
         lease_start = [
-            datetime.datetime(2017, 10, 5, 15, 22, 29, tzinfo=datetime.timezone.utc),
-            datetime.datetime(2017, 10, 10, 12, 5, 14, tzinfo=datetime.timezone.utc),
+            datetime.datetime(2017, 10, 5, 15, 22, 29, tzinfo=utc),
+            datetime.datetime(2017, 10, 10, 12, 5, 14, tzinfo=utc),
         ]
         lease_end = [
-            datetime.datetime(2017, 10, 16, 8, 9, 23, tzinfo=datetime.timezone.utc),
+            datetime.datetime(2017, 10, 16, 8, 9, 23, tzinfo=utc),
             None,
         ]
         result = leases.get()
@@ -240,7 +240,7 @@ def test_get_current_ipv6(self):
 
     def test_gzip_handling(self):
         leases = IscDhcpLeases("isc_dhcp_leases/test_files/debian7.leases.gz", True)
-        lease_start = datetime.datetime(2013, 12, 10, 12, 57, 4, tzinfo=datetime.timezone.utc)
+        lease_start = datetime.datetime(2013, 12, 10, 12, 57, 4, tzinfo=utc)
         lease_end = lease_start + datetime.timedelta(minutes=10)
         result = leases.get()
         self.assertEqual(len(result), 5)

isc_dhcp_leases/test_lease.py

@@ -1,6 +1,6 @@
 import datetime
 from unittest import TestCase
-from isc_dhcp_leases.iscdhcpleases import Lease
+from isc_dhcp_leases.iscdhcpleases import Lease, utc
 from freezegun import freeze_time
 
 __author__ = 'Martijn Braam <martijn@brixit.nl>'
@@ -26,7 +26,7 @@ def test_init(self):
         self.assertEqual(lease.ethernet, "60:a4:4c:b5:6a:dd")
         self.assertEqual(lease.hostname, "Satellite-C700")
         self.assertEqual(
-            lease.start, datetime.datetime(2013, 12, 10, 12, 57, 4, tzinfo=datetime.timezone.utc))
+            lease.start, datetime.datetime(2013, 12, 10, 12, 57, 4, tzinfo=utc))
         self.assertIsNone(lease.end)
         self.assertTrue(lease.valid)
         self.assertFalse(lease.active)
@@ -40,13 +40,13 @@ def _test_valid(self, now=None):
         lease = Lease("192.168.0.1", self.lease_data, now=now)
         self.assertTrue(lease.valid)  # Lease is forever
 
-        lease.end = datetime.datetime(2015, 7, 6, 13, 57, 4, tzinfo=datetime.timezone.utc)
+        lease.end = datetime.datetime(2015, 7, 6, 13, 57, 4, tzinfo=utc)
         self.assertTrue(lease.valid)  # Lease is within start and end
 
         lease.end = lease.end - datetime.timedelta(hours=7)
         self.assertFalse(lease.valid)  # Lease is ended
 
-        lease.start = datetime.datetime(2015, 7, 6, 12, 57, 4, tzinfo=datetime.timezone.utc)
+        lease.start = datetime.datetime(2015, 7, 6, 12, 57, 4, tzinfo=utc)
         lease.end = lease.start + datetime.timedelta(hours=1)
         self.assertFalse(lease.valid)  # Lease is in the future
 
@@ -56,7 +56,7 @@ def test_valid_frozen(self):
 
     def test_valid_historical(self):
         self._test_valid(
-            now=datetime.datetime(2015, 7, 6, 8, 15, 0, tzinfo=datetime.timezone.utc))
+            now=datetime.datetime(2015, 7, 6, 8, 15, 0, tzinfo=utc))
 
     def test_eq(self):
         lease_a = Lease("192.168.0.1", self.lease_data)
@@ -90,7 +90,7 @@ def test_valid_no_starts_property(self):
         lease = Lease("192.168.0.1", self.lease_data)
         self.assertTrue(lease.valid)  # Lease is forever
 
-        lease.end = datetime.datetime(2015, 7, 6, 6, 57, 4, tzinfo=datetime.timezone.utc)
+        lease.end = datetime.datetime(2015, 7, 6, 6, 57, 4, tzinfo=utc)
         self.assertFalse(lease.valid)  # Lease is ended
 
         lease.end = lease.end + datetime.timedelta(hours=3)

isc_dhcp_leases/test_lease6.py

@@ -1,14 +1,14 @@
 import datetime
 from unittest import TestCase
-from isc_dhcp_leases.iscdhcpleases import Lease6
+from isc_dhcp_leases.iscdhcpleases import Lease6, utc
 from freezegun import freeze_time
 
 __author__ = 'Martijn Braam <martijn@brixit.nl>'
 
 
 class TestLease6(TestCase):
     def setUp(self):
-        self.lease_time = datetime.datetime(2015, 8, 18, 16, 55, 37, tzinfo=datetime.timezone.utc)
+        self.lease_time = datetime.datetime(2015, 8, 18, 16, 55, 37, tzinfo=utc)
         self.lease_data = {
             'binding': 'state active',
             'ends': 'never',
@@ -43,7 +43,7 @@ def _test_valid(self, now=None):
                        now=now)
         self.assertTrue(lease.valid)  # Lease is forever
 
-        lease.end = datetime.datetime(2015, 7, 6, 13, 57, 4, tzinfo=datetime.timezone.utc)
+        lease.end = datetime.datetime(2015, 7, 6, 13, 57, 4, tzinfo=utc)
         self.assertTrue(lease.valid)  # Lease is before end
 
         lease.end = lease.end - datetime.timedelta(hours=7)
@@ -55,7 +55,7 @@ def test_valid_frozen(self):
 
     def test_valid_historical(self):
         self._test_valid(
-            now=datetime.datetime(2015, 7, 6, 8, 15, 0, tzinfo=datetime.timezone.utc))
+            now=datetime.datetime(2015, 7, 6, 8, 15, 0, tzinfo=utc))
 
     def test_eq(self):
         lease_a = Lease6("2001:610:600:891d::60", self.lease_data, self.lease_time,