Missing file from previous commit
Change-Id: I79d1f63052eb2d65d6c9726ed0340c1d57997e53
diff --git a/common/utils/id_generation.py b/common/utils/id_generation.py
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+++ b/common/utils/id_generation.py
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+#
+# Copyright 2017 the original author or authors.
+#
+# 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.
+#
+# """ ID generation utils """
+
+from uuid import uuid4
+
+def create_cluster_logical_device_ids(core_id, switch_id):
+ """
+ Creates a logical device id and an OpenFlow datapath id that is unique
+ across the Voltha cluster. Both ids represents a 64 bits integer where
+ the lower 48 bits represents the switch id and the upper 16 bits
+ represents the core id.
+ :param core_id: string
+ :return: cluster logical device id and OpenFlow datapath id
+ """
+ switch_id = format(switch_id, '012x')
+ id = '{}{}'.format(format(int(core_id), '04x'), switch_id)
+ hex_int=int(id,16)
+ return id, hex_int
+
+
+def create_cluster_device_id(core_id):
+ """
+ Creates a device id that is unique across the Voltha cluster.
+ The device id is a str of 64 bits. The lower 48 bits refers to the
+ device id while the upper 16 bits refers to the core id.
+ :param core_id: string
+ :return: cluster device id
+ """
+ return '{}{}'.format(format(int(core_id), '04x'), uuid4().hex[:12])
+
+def get_core_id_from_device_id(device_id):
+ # Device id is a string and the first 4 characters represent the core_id
+ assert device_id and device_id.len() == 16
+ return device_id[:4]
+
+
+def get_core_id_from_logical_device_id(logical_device_id):
+ """
+ Logical Device id is a string and the first 4 characters represent the
+ core_id
+ :param logical_device_id:
+ :return: core_id string
+ """
+ assert logical_device_id and logical_device_id.len() == 16
+ return logical_device_id[:4]
+
+def get_core_id_from_datapath_id(datapath_id):
+ """
+ datapath id is a uint64 where:
+ - low 48 bits -> switch_id
+ - high 16 bits -> core id
+ :param datapath_id:
+ :return: core_id string
+ """
+ assert datapath_id
+ # Get the hex string and remove the '0x' prefix
+ id_in_hex_str=hex(datapath_id)[2:]
+ assert id_in_hex_str.len() > 12
+ return id_in_hex_str[:-12]