VOL-1451 Initial checkin of openonu build

Produced docker container capable of building and running
openonu/brcm_openonci_onu.  Copied over current onu code
and resolved all imports by copying into the local source tree.

Change-Id: Ib9785d37afc65b7d32ecf74aee2456352626e2b6
diff --git a/python/common/pon_resource_manager/resource_manager.py b/python/common/pon_resource_manager/resource_manager.py
new file mode 100644
index 0000000..bdb45ee
--- /dev/null
+++ b/python/common/pon_resource_manager/resource_manager.py
@@ -0,0 +1,1050 @@
+#
+# Copyright 2018 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.
+#
+
+"""
+Resource Manager will be unique for each OLT device.
+
+It exposes APIs to create/free alloc_ids/onu_ids/gemport_ids. Resource Manager
+uses a KV store in backend to ensure resiliency of the data.
+"""
+import json
+import ast
+import structlog
+from bitstring import BitArray
+import shlex
+from argparse import ArgumentParser, ArgumentError
+
+from common.pon_resource_manager.resource_kv_store import ResourceKvStore
+from common.tech_profile.tech_profile import TechProfile
+
+
+# Used to parse extra arguments to OpenOlt adapter from the NBI
+class OltVendorArgumentParser(ArgumentParser):
+    # Must override the exit command to prevent it from
+    # calling sys.exit().  Return exception instead.
+    def exit(self, status=0, message=None):
+        raise Exception(message)
+
+
+class PONResourceManager(object):
+    """Implements APIs to initialize/allocate/release alloc/gemport/onu IDs."""
+
+    # Constants to identify resource pool
+    UNI_ID = 'UNI_ID'
+    ONU_ID = 'ONU_ID'
+    ALLOC_ID = 'ALLOC_ID'
+    GEMPORT_ID = 'GEMPORT_ID'
+    FLOW_ID = 'FLOW_ID'
+
+    # Constants for passing command line arugments
+    OLT_MODEL_ARG = '--olt_model'
+
+    # The resource ranges for a given device model should be placed
+    # at 'resource_manager/<technology>/resource_ranges/<olt_model_type>'
+    # path on the KV store.
+    # If Resource Range parameters are to be read from the external KV store,
+    # they are expected to be stored in the following format.
+    # Note: All parameters are MANDATORY for now.
+    '''
+    {
+        "onu_id_start": 1,
+        "onu_id_end": 127,
+        "alloc_id_start": 1024,
+        "alloc_id_end": 2816,
+        "gemport_id_start": 1024,
+        "gemport_id_end": 8960,
+        "flow_id_start": 1,
+        "flow_id_end": 16383,
+        "uni_id_start": 0,
+        "uni_id_end": 0,
+        "pon_ports": 16
+    }
+
+    '''
+    # constants used as keys to reference the resource range parameters from
+    # and external KV store.
+    UNI_ID_START_IDX = "uni_id_start"
+    UNI_ID_END_IDX = "uni_id_end"
+    ONU_ID_START_IDX = "onu_id_start"
+    ONU_ID_END_IDX = "onu_id_end"
+    ONU_ID_SHARED_IDX = "onu_id_shared"
+    ALLOC_ID_START_IDX = "alloc_id_start"
+    ALLOC_ID_END_IDX = "alloc_id_end"
+    ALLOC_ID_SHARED_IDX = "alloc_id_shared"
+    GEMPORT_ID_START_IDX = "gemport_id_start"
+    GEMPORT_ID_END_IDX = "gemport_id_end"
+    GEMPORT_ID_SHARED_IDX = "gemport_id_shared"
+    FLOW_ID_START_IDX = "flow_id_start"
+    FLOW_ID_END_IDX = "flow_id_end"
+    FLOW_ID_SHARED_IDX = "flow_id_shared"
+    NUM_OF_PON_PORT = "pon_ports"
+
+    # PON Resource range configuration on the KV store.
+    # Format: 'resource_manager/<technology>/resource_ranges/<olt_model_type>'
+    # The KV store backend is initialized with a path prefix and we need to
+    # provide only the suffix.
+    PON_RESOURCE_RANGE_CONFIG_PATH = 'resource_ranges/{}'
+
+    # resource path suffix
+    ALLOC_ID_POOL_PATH = '{}/alloc_id_pool/{}'
+    GEMPORT_ID_POOL_PATH = '{}/gemport_id_pool/{}'
+    ONU_ID_POOL_PATH = '{}/onu_id_pool/{}'
+    FLOW_ID_POOL_PATH = '{}/flow_id_pool/{}'
+
+    # Path on the KV store for storing list of alloc IDs for a given ONU
+    # Format: <device_id>/<(pon_intf_id, onu_id)>/alloc_ids
+    ALLOC_ID_RESOURCE_MAP_PATH = '{}/{}/alloc_ids'
+
+    # Path on the KV store for storing list of gemport IDs for a given ONU
+    # Format: <device_id>/<(pon_intf_id, onu_id)>/gemport_ids
+    GEMPORT_ID_RESOURCE_MAP_PATH = '{}/{}/gemport_ids'
+
+    # Path on the KV store for storing list of Flow IDs for a given ONU
+    # Format: <device_id>/<(pon_intf_id, onu_id)>/flow_ids
+    FLOW_ID_RESOURCE_MAP_PATH = '{}/{}/flow_ids'
+
+    # Flow Id info: Use to store more metadata associated with the flow_id
+    # Format: <device_id>/<(pon_intf_id, onu_id)>/flow_id_info/<flow_id>
+    FLOW_ID_INFO_PATH = '{}/{}/flow_id_info/{}'
+
+    # Constants for internal usage.
+    PON_INTF_ID = 'pon_intf_id'
+    START_IDX = 'start_idx'
+    END_IDX = 'end_idx'
+    POOL = 'pool'
+
+    def __init__(self, technology, extra_args, device_id,
+                 backend, host, port):
+        """
+        Create PONResourceManager object.
+
+        :param technology: PON technology
+        :param: extra_args: This string contains extra arguments passed during
+        pre-provisioning of OLT and specifies the OLT Vendor type
+        :param device_id: OLT device id
+        :param backend: backend store
+        :param host: ip of backend store
+        :param port: port on which backend store listens
+        :raises exception when invalid backend store passed as an argument
+        """
+        # logger
+        self._log = structlog.get_logger()
+
+        try:
+            self.technology = technology
+            self.extra_args = extra_args 
+            self.device_id = device_id
+            self.backend = backend
+            self.host = host
+            self.port = port
+            self.olt_model = None
+
+            self._kv_store = ResourceKvStore(technology, device_id, backend,
+                                             host, port)
+            self.tech_profile = TechProfile(self)
+
+            # Below attribute, pon_resource_ranges, should be initialized
+            # by reading from KV store.
+            self.pon_resource_ranges = dict()
+            self.pon_resource_ranges[PONResourceManager.ONU_ID_SHARED_IDX] = None
+            self.pon_resource_ranges[PONResourceManager.ALLOC_ID_SHARED_IDX] = None
+            self.pon_resource_ranges[PONResourceManager.GEMPORT_ID_SHARED_IDX] = None
+            self.pon_resource_ranges[PONResourceManager.FLOW_ID_SHARED_IDX] = None
+
+            self.shared_resource_mgrs = dict()
+            self.shared_resource_mgrs[PONResourceManager.ONU_ID_SHARED_IDX] = None
+            self.shared_resource_mgrs[PONResourceManager.ALLOC_ID_SHARED_IDX] = None
+            self.shared_resource_mgrs[PONResourceManager.GEMPORT_ID_SHARED_IDX] = None
+            self.shared_resource_mgrs[PONResourceManager.FLOW_ID_SHARED_IDX] = None
+
+            self.shared_idx_by_type = dict()
+            self.shared_idx_by_type[PONResourceManager.ONU_ID] = PONResourceManager.ONU_ID_SHARED_IDX
+            self.shared_idx_by_type[PONResourceManager.ALLOC_ID] = PONResourceManager.ALLOC_ID_SHARED_IDX
+            self.shared_idx_by_type[PONResourceManager.GEMPORT_ID] = PONResourceManager.GEMPORT_ID_SHARED_IDX
+            self.shared_idx_by_type[PONResourceManager.FLOW_ID] = PONResourceManager.FLOW_ID_SHARED_IDX
+
+            self.intf_ids = None
+
+        except Exception as e:
+            self._log.exception("exception-in-init")
+            raise Exception(e)
+
+    def init_resource_ranges_from_kv_store(self):
+        """
+        Initialize PON resource ranges with config fetched from kv store.
+
+        :return boolean: True if PON resource ranges initialized else false
+        """
+        self.olt_model = self._get_olt_model()
+        # Try to initialize the PON Resource Ranges from KV store based on the
+        # OLT model key, if available
+        if self.olt_model is None:
+            self._log.info("device-model-unavailable--not-reading-from-kv-store")
+            return False
+
+        path = self.PON_RESOURCE_RANGE_CONFIG_PATH.format(self.olt_model)
+        try:
+            # get resource from kv store
+            result = self._kv_store.get_from_kv_store(path)
+
+            if result is None:
+                self._log.debug("resource-range-config-unavailable-on-kvstore")
+                return False
+
+            resource_range_config = result
+
+            if resource_range_config is not None:
+                # update internal ranges from kv ranges. If there are missing
+                # values in the KV profile, continue to use the defaults
+                for key,value in json.loads(resource_range_config): self.pon_resource_ranges[key] = value
+
+                # initialize optional elements that may not be in the profile
+                if self.pon_resource_ranges[PONResourceManager.UNI_ID_START_IDX] is None:
+                    self.pon_resource_ranges[PONResourceManager.UNI_ID_START_IDX] = 0
+                if self.pon_resource_ranges[PONResourceManager.UNI_ID_END_IDX] is None:
+                    self.pon_resource_ranges[PONResourceManager.UNI_ID_END_IDX] = 0
+
+                self._log.debug("Init-resource-ranges-from-kvstore-success",
+                                pon_resource_ranges=self.pon_resource_ranges,
+                                path=path)
+                return True
+
+        except Exception as e:
+            self._log.exception("error-initializing-resource-range-from-kv-store",
+                                e=e)
+        return False
+
+    def update_range_(self, start_idx, start, end_idx, end, shared_idx = None, shared_pool_id = None,
+                      shared_resource_mgr = None):
+        if (start is not None) and \
+                (start_idx not in self.pon_resource_ranges or self.pon_resource_ranges[start_idx] < start):
+            self.pon_resource_ranges[start_idx] = start
+        if (end is not None) and \
+                (end_idx not in self.pon_resource_ranges or self.pon_resource_ranges[end_idx] > end):
+            self.pon_resource_ranges[end_idx] = end
+        if (shared_pool_id is not None) and \
+                (shared_idx not in self.pon_resource_ranges or self.pon_resource_ranges[shared_idx] is None):
+            self.pon_resource_ranges[shared_idx] = shared_pool_id
+        if (shared_resource_mgr is not None) and \
+                (shared_idx not in self.shared_resource_mgrs or self.shared_resource_mgrs[shared_idx] is None):
+            self.shared_resource_mgrs[shared_idx] = shared_resource_mgr
+
+    def update_ranges(self,
+                      onu_id_start_idx=None,
+                      onu_id_end_idx=None,
+                      onu_id_shared_pool_id=None,
+                      onu_id_shared_resource_mgr=None,
+                      alloc_id_start_idx=None,
+                      alloc_id_end_idx=None,
+                      alloc_id_shared_pool_id=None,
+                      alloc_id_shared_resource_mgr=None,
+                      gemport_id_start_idx=None,
+                      gemport_id_end_idx=None,
+                      gemport_id_shared_pool_id=None,
+                      gemport_id_shared_resource_mgr=None,
+                      flow_id_start_idx=None,
+                      flow_id_end_idx=None,
+                      flow_id_shared_pool_id=None,
+                      flow_id_shared_resource_mgr=None,
+                      uni_id_start_idx=None,
+                      uni_id_end_idx=None):
+
+        self.update_range_(PONResourceManager.ONU_ID_START_IDX, onu_id_start_idx,
+                           PONResourceManager.ONU_ID_END_IDX, onu_id_end_idx,
+                           PONResourceManager.ONU_ID_SHARED_IDX, onu_id_shared_pool_id,
+                           onu_id_shared_resource_mgr)
+
+        self.update_range_(PONResourceManager.ALLOC_ID_START_IDX, alloc_id_start_idx,
+                           PONResourceManager.ALLOC_ID_END_IDX, alloc_id_end_idx,
+                           PONResourceManager.ALLOC_ID_SHARED_IDX, alloc_id_shared_pool_id,
+                           alloc_id_shared_resource_mgr)
+
+        self.update_range_(PONResourceManager.GEMPORT_ID_START_IDX, gemport_id_start_idx,
+                           PONResourceManager.GEMPORT_ID_END_IDX, gemport_id_end_idx,
+                           PONResourceManager.GEMPORT_ID_SHARED_IDX, gemport_id_shared_pool_id,
+                           gemport_id_shared_resource_mgr)
+
+        self.update_range_(PONResourceManager.FLOW_ID_START_IDX, flow_id_start_idx,
+                           PONResourceManager.FLOW_ID_END_IDX, flow_id_end_idx,
+                           PONResourceManager.FLOW_ID_SHARED_IDX, flow_id_shared_pool_id,
+                           flow_id_shared_resource_mgr)
+
+        self.update_range_(PONResourceManager.UNI_ID_START_IDX, uni_id_start_idx,
+                           PONResourceManager.UNI_ID_END_IDX, uni_id_end_idx)
+
+    def init_default_pon_resource_ranges(self,
+                                         onu_id_start_idx=1,
+                                         onu_id_end_idx=127,
+                                         onu_id_shared_pool_id=None,
+                                         alloc_id_start_idx=1024,
+                                         alloc_id_end_idx=2816,
+                                         alloc_id_shared_pool_id=None,
+                                         gemport_id_start_idx=1024,
+                                         gemport_id_end_idx=8960,
+                                         gemport_id_shared_pool_id=None,
+                                         flow_id_start_idx=1,
+                                         flow_id_end_idx=16383,
+                                         flow_id_shared_pool_id=None,
+                                         uni_id_start_idx=0,
+                                         uni_id_end_idx=0,
+                                         num_of_pon_ports=16,
+                                         intf_ids=None):
+        """
+        Initialize default PON resource ranges
+
+        :param onu_id_start_idx: onu id start index
+        :param onu_id_end_idx: onu id end index
+        :param onu_id_shared_pool_id: pool idx for id shared by all intfs or None for no sharing
+        :param alloc_id_start_idx: alloc id start index
+        :param alloc_id_end_idx: alloc id end index
+        :param alloc_id_shared_pool_id: pool idx for alloc id shared by all intfs or None for no sharing
+        :param gemport_id_start_idx: gemport id start index
+        :param gemport_id_end_idx: gemport id end index
+        :param gemport_id_shared_pool_id: pool idx for gemport id shared by all intfs or None for no sharing
+        :param flow_id_start_idx: flow id start index
+        :param flow_id_end_idx: flow id end index
+        :param flow_id_shared_pool_id: pool idx for flow id shared by all intfs or None for no sharing
+        :param num_of_pon_ports: number of PON ports
+        :param intf_ids: interfaces serviced by this manager
+        """
+        self._log.info("initialize-default-resource-range-values")
+
+        self.update_ranges(onu_id_start_idx, onu_id_end_idx, onu_id_shared_pool_id, None,
+                           alloc_id_start_idx, alloc_id_end_idx, alloc_id_shared_pool_id, None,
+                           gemport_id_start_idx, gemport_id_end_idx, gemport_id_shared_pool_id, None,
+                           flow_id_start_idx, flow_id_end_idx, flow_id_shared_pool_id, None,
+                           uni_id_start_idx, uni_id_end_idx)
+
+        if intf_ids is None:
+            intf_ids = range(0, num_of_pon_ports)
+
+        self.intf_ids = intf_ids
+
+    def init_device_resource_pool(self):
+        """
+        Initialize resource pool for all PON ports.
+        """
+
+        self._log.info("init-device-resource-pool", technology=self.technology,
+                       pon_resource_ranges=self.pon_resource_ranges)
+
+        for i in self.intf_ids:
+            shared_pool_id = self.pon_resource_ranges[PONResourceManager.ONU_ID_SHARED_IDX]
+            if shared_pool_id is not None:
+                i = shared_pool_id
+            self.init_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.ONU_ID,
+                start_idx=self.pon_resource_ranges[
+                    PONResourceManager.ONU_ID_START_IDX],
+                end_idx=self.pon_resource_ranges[
+                    PONResourceManager.ONU_ID_END_IDX])
+            if shared_pool_id is not None:
+                break
+
+        for i in self.intf_ids:
+            shared_pool_id = self.pon_resource_ranges[PONResourceManager.ALLOC_ID_SHARED_IDX]
+            if shared_pool_id is not None:
+                i = shared_pool_id
+            self.init_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.ALLOC_ID,
+                start_idx=self.pon_resource_ranges[
+                    PONResourceManager.ALLOC_ID_START_IDX],
+                end_idx=self.pon_resource_ranges[
+                    PONResourceManager.ALLOC_ID_END_IDX])
+            if shared_pool_id is not None:
+                break
+
+        for i in self.intf_ids:
+            shared_pool_id = self.pon_resource_ranges[PONResourceManager.GEMPORT_ID_SHARED_IDX]
+            if shared_pool_id is not None:
+                i = shared_pool_id
+            self.init_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.GEMPORT_ID,
+                start_idx=self.pon_resource_ranges[
+                    PONResourceManager.GEMPORT_ID_START_IDX],
+                end_idx=self.pon_resource_ranges[
+                    PONResourceManager.GEMPORT_ID_END_IDX])
+            if shared_pool_id is not None:
+                break
+
+        for i in self.intf_ids:
+            shared_pool_id = self.pon_resource_ranges[PONResourceManager.FLOW_ID_SHARED_IDX]
+            if shared_pool_id is not None:
+                i = shared_pool_id
+            self.init_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.FLOW_ID,
+                start_idx=self.pon_resource_ranges[
+                    PONResourceManager.FLOW_ID_START_IDX],
+                end_idx=self.pon_resource_ranges[
+                    PONResourceManager.FLOW_ID_END_IDX])
+            if shared_pool_id is not None:
+                break
+
+    def clear_device_resource_pool(self):
+        """
+        Clear resource pool of all PON ports.
+        """
+        for i in self.intf_ids:
+            shared_pool_id = self.pon_resource_ranges[PONResourceManager.ONU_ID_SHARED_IDX]
+            if shared_pool_id is not None:
+                i = shared_pool_id
+            self.clear_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.ONU_ID,
+            )
+            if shared_pool_id is not None:
+                break
+
+        for i in self.intf_ids:
+            shared_pool_id = self.pon_resource_ranges[PONResourceManager.ALLOC_ID_SHARED_IDX]
+            if shared_pool_id is not None:
+                i = shared_pool_id
+            self.clear_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.ALLOC_ID,
+            )
+            if shared_pool_id is not None:
+                break
+
+        for i in self.intf_ids:
+            shared_pool_id = self.pon_resource_ranges[PONResourceManager.GEMPORT_ID_SHARED_IDX]
+            if shared_pool_id is not None:
+                i = shared_pool_id
+            self.clear_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.GEMPORT_ID,
+            )
+            if shared_pool_id is not None:
+                break
+
+        for i in self.intf_ids:
+            shared_pool_id = self.pon_resource_ranges[PONResourceManager.FLOW_ID_SHARED_IDX]
+            if shared_pool_id is not None:
+                i = shared_pool_id
+            self.clear_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.FLOW_ID,
+            )
+            if shared_pool_id is not None:
+                break
+
+    def init_resource_id_pool(self, pon_intf_id, resource_type, start_idx,
+                              end_idx):
+        """
+        Initialize Resource ID pool for a given Resource Type on a given PON Port
+
+        :param pon_intf_id: OLT PON interface id
+        :param resource_type: String to identify type of resource
+        :param start_idx: start index for onu id pool
+        :param end_idx: end index for onu id pool
+        :return boolean: True if resource id pool initialized else false
+        """
+        status = False
+
+        # delegate to the master instance if sharing enabled across instances
+        shared_resource_mgr = self.shared_resource_mgrs[self.shared_idx_by_type[resource_type]]
+        if shared_resource_mgr is not None and shared_resource_mgr is not self:
+            return shared_resource_mgr.init_resource_id_pool(pon_intf_id, resource_type,
+                                                             start_idx, end_idx)
+
+        path = self._get_path(pon_intf_id, resource_type)
+        if path is None:
+            return status
+
+        try:
+            # In case of adapter reboot and reconciliation resource in kv store
+            # checked for its presence if not kv store update happens
+            resource = self._get_resource(path)
+
+            if resource is not None:
+                self._log.info("Resource-already-present-in-store", path=path)
+                status = True
+            else:
+                resource = self._format_resource(pon_intf_id, start_idx,
+                                                 end_idx)
+                self._log.info("Resource-initialized", path=path)
+
+                # Add resource as json in kv store.
+                result = self._kv_store.update_to_kv_store(path, resource)
+                if result is True:
+                    status = True
+
+        except Exception as e:
+            self._log.exception("error-initializing-resource-pool", e=e)
+
+        return status
+
+    def assert_resource_limits(self, id, resource_type):
+        """
+        Assert the specified id value is in the limit bounds of he requested resource type.
+
+        :param id: The value to assert is in limits
+        :param resource_type: String to identify type of resource
+        """
+        start_idx = PONResourceManager.ONU_ID_START_IDX if resource_type == PONResourceManager.ONU_ID \
+            else PONResourceManager.ALLOC_ID_START_IDX if resource_type == PONResourceManager.ALLOC_ID \
+            else PONResourceManager.GEMPORT_ID_START_IDX if resource_type == PONResourceManager.GEMPORT_ID \
+            else PONResourceManager.FLOW_ID_START_IDX if resource_type == PONResourceManager.FLOW_ID \
+            else PONResourceManager.UNI_ID_START_IDX if resource_type == PONResourceManager.UNI_ID \
+            else None
+        end_idx = PONResourceManager.ONU_ID_END_IDX if resource_type == PONResourceManager.ONU_ID \
+            else PONResourceManager.ALLOC_ID_END_IDX if resource_type == PONResourceManager.ALLOC_ID \
+            else PONResourceManager.GEMPORT_ID_END_IDX if resource_type == PONResourceManager.GEMPORT_ID \
+            else PONResourceManager.FLOW_ID_END_IDX if resource_type == PONResourceManager.FLOW_ID \
+            else PONResourceManager.UNI_ID_END_IDX if resource_type == PONResourceManager.UNI_ID \
+            else None
+        assert id >= self.pon_resource_ranges[start_idx] and id <= self.pon_resource_ranges[end_idx]
+
+    def get_resource_id(self, pon_intf_id, resource_type, num_of_id=1):
+        """
+        Create alloc/gemport/onu/flow id for given OLT PON interface.
+
+        :param pon_intf_id: OLT PON interface id
+        :param resource_type: String to identify type of resource
+        :param num_of_id: required number of ids
+        :return list/int/None: list, int or None if resource type is
+                               alloc_id/gemport_id, onu_id or invalid type
+                               respectively
+        """
+        result = None
+
+        if num_of_id < 1:
+            self._log.error("invalid-num-of-resources-requested")
+            return result
+
+        # delegate to the master instance if sharing enabled across instances
+        shared_resource_mgr = self.shared_resource_mgrs[self.shared_idx_by_type[resource_type]]
+        if shared_resource_mgr is not None and shared_resource_mgr is not self:
+            return shared_resource_mgr.get_resource_id(pon_intf_id, resource_type, num_of_id)
+
+        path = self._get_path(pon_intf_id, resource_type)
+        if path is None:
+            return result
+
+        try:
+            resource = self._get_resource(path)
+            if resource is not None and \
+                    (resource_type == PONResourceManager.ONU_ID or
+                     resource_type == PONResourceManager.FLOW_ID):
+                result = self._generate_next_id(resource)
+            elif resource is not None and (
+                    resource_type == PONResourceManager.GEMPORT_ID or
+                    resource_type == PONResourceManager.ALLOC_ID):
+                if num_of_id == 1:
+                    result = self._generate_next_id(resource)
+                else:
+                    result = list()
+                    while num_of_id > 0:
+                        result.append(self._generate_next_id(resource))
+                        num_of_id -= 1
+            else:
+                raise Exception("get-resource-failed")
+
+            self._log.debug("Get-" + resource_type + "-success", result=result,
+                            path=path)
+            # Update resource in kv store
+            self._update_resource(path, resource)
+
+        except Exception as e:
+            self._log.exception("Get-" + resource_type + "-id-failed",
+                                path=path, e=e)
+        return result
+
+    def free_resource_id(self, pon_intf_id, resource_type, release_content):
+        """
+        Release alloc/gemport/onu/flow id for given OLT PON interface.
+
+        :param pon_intf_id: OLT PON interface id
+        :param resource_type: String to identify type of resource
+        :param release_content: required number of ids
+        :return boolean: True if all IDs in given release_content released
+                         else False
+        """
+        status = False
+        known_resource_types = [PONResourceManager.ONU_ID,
+                                PONResourceManager.ALLOC_ID,
+                                PONResourceManager.GEMPORT_ID,
+                                PONResourceManager.FLOW_ID]
+        if resource_type not in known_resource_types:
+            self._log.error("unknown-resource-type",
+                            resource_type=resource_type)
+            return status
+        if release_content is None:
+            self._log.debug("nothing-to-release")
+            return status
+        # delegate to the master instance if sharing enabled across instances
+        shared_resource_mgr = self.shared_resource_mgrs[self.shared_idx_by_type[resource_type]]
+        if shared_resource_mgr is not None and shared_resource_mgr is not self:
+            return shared_resource_mgr.free_resource_id(pon_intf_id, resource_type)
+
+        path = self._get_path(pon_intf_id, resource_type)
+        if path is None:
+            return status
+
+        try:
+            resource = self._get_resource(path)
+            if resource is None:
+                raise Exception("get-resource-failed")
+            if isinstance(release_content, list):
+                for content in release_content:
+                    self._release_id(resource, content)
+            else:
+                self._release_id(resource, release_content)
+
+            self._log.debug("Free-" + resource_type + "-success", path=path)
+
+            # Update resource in kv store
+            status = self._update_resource(path, resource)
+
+        except Exception as e:
+            self._log.exception("Free-" + resource_type + "-failed",
+                                path=path, e=e)
+        return status
+
+    def clear_resource_id_pool(self, pon_intf_id, resource_type):
+        """
+        Clear Resource Pool for a given Resource Type on a given PON Port.
+
+        :return boolean: True if removed else False
+        """
+
+        # delegate to the master instance if sharing enabled across instances
+        shared_resource_mgr = self.shared_resource_mgrs[self.shared_idx_by_type[resource_type]]
+        if shared_resource_mgr is not None and shared_resource_mgr is not self:
+            return shared_resource_mgr.clear_resource_id_pool(pon_intf_id, resource_type)
+
+        path = self._get_path(pon_intf_id, resource_type)
+        if path is None:
+            return False
+
+        try:
+            result = self._kv_store.remove_from_kv_store(path)
+            if result is True:
+                self._log.debug("Resource-pool-cleared",
+                                device_id=self.device_id,
+                                path=path)
+                return True
+        except Exception as e:
+            self._log.exception("error-clearing-resource-pool", e=e)
+
+        self._log.error("Clear-resource-pool-failed", device_id=self.device_id,
+                        path=path)
+        return False
+
+    def init_resource_map(self, pon_intf_onu_id):
+        """
+        Initialize resource map
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+        """
+        # initialize pon_intf_onu_id tuple to alloc_ids map
+        alloc_id_path = PONResourceManager.ALLOC_ID_RESOURCE_MAP_PATH.format(
+            self.device_id, str(pon_intf_onu_id)
+        )
+        alloc_ids = list()
+        self._kv_store.update_to_kv_store(
+            alloc_id_path, json.dumps(alloc_ids)
+        )
+
+        # initialize pon_intf_onu_id tuple to gemport_ids map
+        gemport_id_path = PONResourceManager.GEMPORT_ID_RESOURCE_MAP_PATH.format(
+            self.device_id, str(pon_intf_onu_id)
+        )
+        gemport_ids = list()
+        self._kv_store.update_to_kv_store(
+            gemport_id_path, json.dumps(gemport_ids)
+        )
+
+    def remove_resource_map(self, pon_intf_onu_id):
+        """
+        Remove resource map
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+        """
+        # remove pon_intf_onu_id tuple to alloc_ids map
+        try:
+            alloc_id_path = PONResourceManager.ALLOC_ID_RESOURCE_MAP_PATH.format(
+                self.device_id, str(pon_intf_onu_id)
+            )
+            self._kv_store.remove_from_kv_store(alloc_id_path)
+        except Exception as e:
+            self._log.error("error-removing-alloc-id", e=e)
+
+        try:
+            # remove pon_intf_onu_id tuple to gemport_ids map
+            gemport_id_path = PONResourceManager.GEMPORT_ID_RESOURCE_MAP_PATH.format(
+                self.device_id, str(pon_intf_onu_id)
+            )
+            self._kv_store.remove_from_kv_store(gemport_id_path)
+        except Exception as e:
+            self._log.error("error-removing-gem-ports", e=e)
+
+        flow_id_path = PONResourceManager.FLOW_ID_RESOURCE_MAP_PATH.format(
+            self.device_id, str(pon_intf_onu_id))
+        flow_ids = self._kv_store.get_from_kv_store(flow_id_path)
+
+        if flow_ids and isinstance(flow_ids, list):
+            for flow_id in flow_ids:
+                try:
+                    flow_id_info_path = PONResourceManager.FLOW_ID_INFO_PATH.format(
+                                        self.device_id, str(pon_intf_onu_id), flow_id)
+                    self._kv_store.remove_from_kv_store(flow_id_info_path)
+                except Exception as e:
+                    self._log.error("error-removing-flow-info", flow_id=flow_id, e=e)
+                    continue
+        try:
+            self._kv_store.remove_from_kv_store(flow_id_path)
+        except Exception as e:
+            self._log.error("error-removing-flow-ids", e=e)
+
+    def get_current_alloc_ids_for_onu(self, pon_intf_onu_id):
+        """
+        Get currently configured alloc ids for given pon_intf_onu_id
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+
+        :return list: List of alloc_ids if available, else None
+        """
+        path = PONResourceManager.ALLOC_ID_RESOURCE_MAP_PATH.format(
+            self.device_id,
+            str(pon_intf_onu_id))
+        value = self._kv_store.get_from_kv_store(path)
+        if value is not None:
+            alloc_id_list = json.loads(value)
+            if len(alloc_id_list) > 0:
+                return alloc_id_list
+
+        return None
+
+    def get_current_gemport_ids_for_onu(self, pon_intf_onu_id):
+        """
+        Get currently configured gemport ids for given pon_intf_onu_id
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+
+        :return list: List of gemport IDs if available, else None
+        """
+
+        path = PONResourceManager.GEMPORT_ID_RESOURCE_MAP_PATH.format(
+            self.device_id,
+            str(pon_intf_onu_id))
+        value = self._kv_store.get_from_kv_store(path)
+        if value is not None:
+            gemport_id_list = json.loads(value)
+            if len(gemport_id_list) > 0:
+                return gemport_id_list
+
+        return None
+
+    def get_current_flow_ids_for_onu(self, pon_intf_onu_id):
+        """
+        Get currently configured flow ids for given pon_intf_onu_id
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+
+        :return list: List of Flow IDs if available, else None
+        """
+
+        path = PONResourceManager.FLOW_ID_RESOURCE_MAP_PATH.format(
+            self.device_id,
+            str(pon_intf_onu_id))
+        value = self._kv_store.get_from_kv_store(path)
+        if value is not None:
+            flow_id_list = json.loads(value)
+            assert(isinstance(flow_id_list, list))
+            if len(flow_id_list) > 0:
+                return flow_id_list
+
+        return None
+
+    def get_flow_id_info(self, pon_intf_onu_id, flow_id):
+        """
+        Get flow_id details configured for the ONU.
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+        :param flow_id: Flow Id reference
+
+        :return blob: Flow data blob if available, else None
+        """
+
+        path = PONResourceManager.FLOW_ID_INFO_PATH.format(
+            self.device_id,
+            str(pon_intf_onu_id),
+            flow_id)
+        value = self._kv_store.get_from_kv_store(path)
+        if value is not None:
+            return ast.literal_eval(value)
+
+        return None
+
+    def remove_flow_id_info(self, pon_intf_onu_id, flow_id):
+        """
+        Get flow_id details configured for the ONU.
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+        :param flow_id: Flow Id reference
+
+        """
+
+        path = PONResourceManager.FLOW_ID_INFO_PATH.format(
+            self.device_id,
+            str(pon_intf_onu_id),
+            flow_id)
+        self._kv_store.remove_from_kv_store(path)
+
+    def update_alloc_ids_for_onu(self, pon_intf_onu_id, alloc_ids):
+        """
+        Update currently configured alloc ids for given pon_intf_onu_id
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+        :param alloc_ids: list of alloc ids
+        """
+        path = PONResourceManager.ALLOC_ID_RESOURCE_MAP_PATH.format(
+            self.device_id, str(pon_intf_onu_id)
+        )
+        self._kv_store.update_to_kv_store(
+            path, json.dumps(alloc_ids)
+        )
+
+    def update_gemport_ids_for_onu(self, pon_intf_onu_id, gemport_ids):
+        """
+        Update currently configured gemport ids for given pon_intf_onu_id
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+        :param gemport_ids: list of gem port ids
+        """
+        path = PONResourceManager.GEMPORT_ID_RESOURCE_MAP_PATH.format(
+            self.device_id, str(pon_intf_onu_id)
+        )
+        self._kv_store.update_to_kv_store(
+            path, json.dumps(gemport_ids)
+        )
+
+    def update_flow_id_for_onu(self, pon_intf_onu_id, flow_id, add=True):
+        """
+        Update the flow_id list of the ONU (add or remove flow_id from the list)
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+        :param flow_id: flow ID
+        :param add: Boolean flag to indicate whether the flow_id should be
+                    added or removed from the list. Defaults to adding the flow.
+        """
+        path = PONResourceManager.FLOW_ID_RESOURCE_MAP_PATH.format(
+            self.device_id, str(pon_intf_onu_id)
+        )
+        current_flow_ids = self.get_current_flow_ids_for_onu(pon_intf_onu_id)
+        if not isinstance(current_flow_ids, list):
+            # When the first flow_id is being added, the current_flow_ids is None
+            current_flow_ids = list()
+
+        if add:
+            if flow_id not in current_flow_ids:
+                current_flow_ids.append(flow_id)
+        else:
+            if flow_id in current_flow_ids:
+                current_flow_ids.remove(flow_id)
+
+        self._kv_store.update_to_kv_store(path, current_flow_ids)
+
+    def update_flow_id_info_for_onu(self, pon_intf_onu_id, flow_id, flow_data):
+        """
+        Update any metadata associated with the flow_id. The flow_data could be json
+        or any of other data structure. The resource manager doesnt care
+
+        :param pon_intf_onu_id: reference of PON interface id and onu id
+        :param flow_id: Flow ID
+        :param flow_data: Flow data blob
+        """
+        path = PONResourceManager.FLOW_ID_INFO_PATH.format(
+            self.device_id, str(pon_intf_onu_id), flow_id
+        )
+
+        if not self._kv_store.update_to_kv_store(path, flow_data):
+            self._log.error("flow-info-update-failed", path=path, flow_id=flow_id)
+
+    def _get_olt_model(self):
+        """
+        Get olt model variant
+
+        :return: type of olt model 
+        """
+        olt_model = None
+        if self.extra_args and len(self.extra_args) > 0:
+            parser = OltVendorArgumentParser(add_help=False)
+            parser.add_argument(PONResourceManager.OLT_MODEL_ARG, '-m', action='store', default='default')
+            try:
+                args = parser.parse_args(shlex.split(self.extra_args))
+                self._log.debug('parsing-extra-arguments', args=args)
+                olt_model = args.olt_model
+            except ArgumentError as e:
+                self._log.exception('invalid-arguments: {}', e=e)
+            except Exception as e:
+                self._log.exception('option-parsing-error: {}', e=e)
+
+        self._log.debug('olt-model', olt_model=olt_model)
+        return olt_model
+
+    def _generate_next_id(self, resource):
+        """
+        Generate unique id having OFFSET as start index.
+
+        :param resource: resource used to generate ID
+        :return int: generated id
+        """
+        pos = resource[PONResourceManager.POOL].find('0b0')
+        resource[PONResourceManager.POOL].set(1, pos)
+        return pos[0] + resource[PONResourceManager.START_IDX]
+
+    def _release_id(self, resource, unique_id):
+        """
+        Release unique id having OFFSET as start index.
+
+        :param resource: resource used to release ID
+        :param unique_id: id need to be released
+        """
+        pos = ((int(unique_id)) - resource[PONResourceManager.START_IDX])
+        resource[PONResourceManager.POOL].set(0, pos)
+
+    def _get_path(self, pon_intf_id, resource_type):
+        """
+        Get path for given resource type.
+
+        :param pon_intf_id: OLT PON interface id
+        :param resource_type: String to identify type of resource
+        :return: path for given resource type
+        """
+
+        shared_pool_id = self.pon_resource_ranges[self.shared_idx_by_type[resource_type]]
+        if shared_pool_id is not None:
+            pon_intf_id = shared_pool_id
+
+        path = None
+        if resource_type == PONResourceManager.ONU_ID:
+            path = self._get_onu_id_resource_path(pon_intf_id)
+        elif resource_type == PONResourceManager.ALLOC_ID:
+            path = self._get_alloc_id_resource_path(pon_intf_id)
+        elif resource_type == PONResourceManager.GEMPORT_ID:
+            path = self._get_gemport_id_resource_path(pon_intf_id)
+        elif resource_type == PONResourceManager.FLOW_ID:
+            path = self._get_flow_id_resource_path(pon_intf_id)
+        else:
+            self._log.error("invalid-resource-pool-identifier")
+        return path
+
+    def _get_flow_id_resource_path(self, pon_intf_id):
+        """
+        Get flow id resource path.
+
+        :param pon_intf_id: OLT PON interface id
+        :return: flow id resource path
+        """
+        return PONResourceManager.FLOW_ID_POOL_PATH.format(
+            self.device_id, pon_intf_id)
+
+    def _get_alloc_id_resource_path(self, pon_intf_id):
+        """
+        Get alloc id resource path.
+
+        :param pon_intf_id: OLT PON interface id
+        :return: alloc id resource path
+        """
+        return PONResourceManager.ALLOC_ID_POOL_PATH.format(
+            self.device_id, pon_intf_id)
+
+    def _get_gemport_id_resource_path(self, pon_intf_id):
+        """
+        Get gemport id resource path.
+
+        :param pon_intf_id: OLT PON interface id
+        :return: gemport id resource path
+        """
+        return PONResourceManager.GEMPORT_ID_POOL_PATH.format(
+            self.device_id, pon_intf_id)
+
+    def _get_onu_id_resource_path(self, pon_intf_id):
+        """
+        Get onu id resource path.
+
+        :param pon_intf_id: OLT PON interface id
+        :return: onu id resource path
+        """
+        return PONResourceManager.ONU_ID_POOL_PATH.format(
+            self.device_id, pon_intf_id)
+
+    def _update_resource(self, path, resource):
+        """
+        Update resource in resource kv store.
+
+        :param path: path to update resource
+        :param resource: resource need to be updated
+        :return boolean: True if resource updated in kv store else False
+        """
+        resource[PONResourceManager.POOL] = \
+            resource[PONResourceManager.POOL].bin
+        result = self._kv_store.update_to_kv_store(path, json.dumps(resource))
+        if result is True:
+            return True
+        return False
+
+    def _get_resource(self, path):
+        """
+        Get resource from kv store.
+
+        :param path: path to get resource
+        :return: resource if resource present in kv store else None
+        """
+        # get resource from kv store
+        result = self._kv_store.get_from_kv_store(path)
+        if result is None:
+            return result
+        self._log.info("dumping resource", result=result)
+        resource = result
+
+        if resource is not None:
+            # decode resource fetched from backend store to dictionary
+            resource = json.loads(resource)
+
+            # resource pool in backend store stored as binary string whereas to
+            # access the pool to generate/release IDs it need to be converted
+            # as BitArray
+            resource[PONResourceManager.POOL] = \
+                BitArray('0b' + resource[PONResourceManager.POOL])
+
+        return resource
+
+    def _format_resource(self, pon_intf_id, start_idx, end_idx):
+        """
+        Format resource as json.
+
+        :param pon_intf_id: OLT PON interface id
+        :param start_idx: start index for id pool
+        :param end_idx: end index for id pool
+        :return dictionary: resource formatted as dictionary
+        """
+        # Format resource as json to be stored in backend store
+        resource = dict()
+        resource[PONResourceManager.PON_INTF_ID] = pon_intf_id
+        resource[PONResourceManager.START_IDX] = start_idx
+        resource[PONResourceManager.END_IDX] = end_idx
+
+        # resource pool stored in backend store as binary string
+        resource[PONResourceManager.POOL] = BitArray(end_idx).bin
+
+        return json.dumps(resource)