Make sure no duplicate stack name when creating k8s bay

Change-Id: I2ef6ef9f8cdd317d574312ac591f5e65bf227d2e
Closes-Bug: #1412497

magnum/common/short_id.py

@@ -0,0 +1,59 @@
+#
+#    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.
+
+"""Utilities for creating short ID strings based on a random UUID.
+
+The IDs each comprise 12 (lower-case) alphanumeric characters.
+"""
+
+import base64
+import uuid
+
+import six
+
+from magnum.openstack.common._i18n import _
+
+
+def _to_byte_string(value, num_bits):
+    """Convert an integer to a big-endian string of bytes with padding.
+
+    Padding is added at the end (i.e. after the least-significant bit) if
+    required.
+    """
+    shifts = six.moves.xrange(num_bits - 8, -8, -8)
+    byte_at = lambda off: (value >> off if off >= 0 else value << -off) & 0xff
+    return ''.join(chr(byte_at(offset)) for offset in shifts)
+
+
+def get_id(source_uuid):
+    """Derive a short (12 character) id from a random UUID.
+
+    The supplied UUID must be a version 4 UUID object.
+    """
+    if isinstance(source_uuid, six.string_types):
+        source_uuid = uuid.UUID(source_uuid)
+    if source_uuid.version != 4:
+        raise ValueError(_('Invalid UUID version (%d)') % source_uuid.version)
+
+    # The "time" field of a v4 UUID contains 60 random bits
+    # (see RFC4122, Section 4.4)
+    random_bytes = _to_byte_string(source_uuid.time, 60)
+    # The first 12 bytes (= 60 bits) of base32-encoded output is our data
+    encoded = base64.b32encode(random_bytes)[:12]
+
+    return encoded.lower()
+
+
+def generate_id():
+    """Generate a short (12 character), random id."""
+    return get_id(uuid.uuid4())

magnum/conductor/handlers/bay_k8s_heat.py

@@ -17,6 +17,7 @@ from heatclient import exc
 from oslo.config import cfg
 
 from magnum.common import clients
+from magnum.common import short_id
 from magnum import objects
 from magnum.openstack.common._i18n import _
 from magnum.openstack.common import log as logging
@@ -73,8 +74,10 @@ def _create_stack(ctxt, osc, bay):
 
     tpl_files, template = template_utils.get_template_contents(
                                         cfg.CONF.k8s_heat.template_path)
+    # Make sure no duplicate stack name
+    stack_name = '%s-%s' % (bay.name, short_id.generate_id())
     fields = {
-        'stack_name': bay.name,
+        'stack_name': stack_name,
         'parameters': bay_definition,
         'template': template,
         'files': dict(list(tpl_files.items()))

magnum/tests/common/test_short_id.py

@@ -0,0 +1,72 @@
+#
+#    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 uuid
+
+import testtools
+
+from magnum.common import short_id
+
+
+class ShortIdTest(testtools.TestCase):
+
+    def test_byte_string_8(self):
+        self.assertEqual('\xab', short_id._to_byte_string(0xab, 8))
+        self.assertEqual('\x05', short_id._to_byte_string(0x05, 8))
+
+    def test_byte_string_16(self):
+        self.assertEqual('\xab\xcd', short_id._to_byte_string(0xabcd, 16))
+        self.assertEqual('\x0a\xbc', short_id._to_byte_string(0xabc, 16))
+
+    def test_byte_string_12(self):
+        self.assertEqual('\xab\xc0', short_id._to_byte_string(0xabc, 12))
+        self.assertEqual('\x0a\xb0', short_id._to_byte_string(0x0ab, 12))
+
+    def test_byte_string_60(self):
+        val = 0x111111111111111
+        byte_string = short_id._to_byte_string(val, 60)
+        self.assertEqual('\x11\x11\x11\x11\x11\x11\x11\x10', byte_string)
+
+    def test_get_id_string(self):
+        id = short_id.get_id('11111111-1111-4111-bfff-ffffffffffff')
+        self.assertEqual('ceirceirceir', id)
+
+    def test_get_id_uuid_1(self):
+        source = uuid.UUID('11111111-1111-4111-bfff-ffffffffffff')
+        self.assertEqual(0x111111111111111, source.time)
+        self.assertEqual('ceirceirceir', short_id.get_id(source))
+
+    def test_get_id_uuid_f(self):
+        source = uuid.UUID('ffffffff-ffff-4fff-8000-000000000000')
+        self.assertEqual('777777777777', short_id.get_id(source))
+
+    def test_get_id_uuid_0(self):
+        source = uuid.UUID('00000000-0000-4000-bfff-ffffffffffff')
+        self.assertEqual('aaaaaaaaaaaa', short_id.get_id(source))
+
+    def test_get_id_uuid_endianness(self):
+        source = uuid.UUID('ffffffff-00ff-4000-aaaa-aaaaaaaaaaaa')
+        self.assertEqual('aaaa77777777', short_id.get_id(source))
+
+    def test_get_id_uuid1(self):
+        source = uuid.uuid1()
+        self.assertRaises(ValueError, short_id.get_id, source)
+
+    def test_generate_ids(self):
+        allowed_chars = 'abcdefghijklmnopqrstuvwxyz234567'
+        ids = [short_id.generate_id() for i in range(25)]
+
+        for id in ids:
+            self.assertEqual(12, len(id))
+            self.assertFalse(id.translate(None, allowed_chars))
+            self.assertEqual(1, ids.count(id))

magnum/tests/conductor/handlers/test_bay_k8s_heat.py

@@ -137,18 +137,22 @@ class TestBayK8sHeat(base.BaseTestCase):
         parsed_outputs = bay_k8s_heat._parse_stack_outputs(outputs)
         self.assertEqual(expected_return_value, parsed_outputs)
 
+    @patch('magnum.common.short_id.generate_id')
     @patch('heatclient.common.template_utils.get_template_contents')
     @patch('magnum.objects.BayModel.get_by_uuid')
     @patch('magnum.conductor.handlers.bay_k8s_heat._extract_bay_definition')
     def test_create_stack(self,
                           mock_extract_bay_definition,
                           mock_objects_baymodel_get_by_uuid,
-                          mock_get_template_contents):
+                          mock_get_template_contents,
+                          mock_generate_id):
 
-        expected_stack_name = 'expected_stack_name'
+        mock_generate_id.return_value = 'xx-xx-xx-xx'
+        expected_stack_name = 'expected_stack_name-xx-xx-xx-xx'
         expected_number_of_minions = 1
         expected_template_contents = 'template_contents'
         exptected_files = []
+        dummy_bay_name = 'expected_stack_name'
 
         mock_tpl_files = mock.MagicMock()
         mock_tpl_files.items.return_value = exptected_files
@@ -160,7 +164,7 @@ class TestBayK8sHeat(base.BaseTestCase):
         mock_osc = mock.MagicMock()
         mock_osc.heat.return_value = mock_heat_client
         mock_bay = mock.MagicMock()
-        mock_bay.name = expected_stack_name
+        mock_bay.name = dummy_bay_name
         mock_bay.node_count = expected_number_of_minions
 
         bay_k8s_heat._create_stack({}, mock_osc, mock_bay)