VOL-1097 : Ofagent integration for voltha 2.0

- Created a common location for python based components
- Adjusted the ofagent component to interact with voltha 2.0
- Added streaming rpc methods for rcv/send of packets to voltha api
- Adjusted voltha.proto

Change-Id: I47fb7b80878ead060b4b42bd16cb4f8aa384fdb6
diff --git a/python/common/pon_resource_manager/__init__.py b/python/common/pon_resource_manager/__init__.py
new file mode 100644
index 0000000..2d104e0
--- /dev/null
+++ b/python/common/pon_resource_manager/__init__.py
@@ -0,0 +1,13 @@
+# Copyright 2017-present Open Networking Foundation

+#

+# 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.

diff --git a/python/common/pon_resource_manager/resource_kv_store.py b/python/common/pon_resource_manager/resource_kv_store.py
new file mode 100644
index 0000000..a1a5c14
--- /dev/null
+++ b/python/common/pon_resource_manager/resource_kv_store.py
@@ -0,0 +1,107 @@
+#

+# 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 KV store - interface between Resource Manager and backend store."""

+import structlog

+

+from voltha.core.config.config_backend import ConsulStore

+from voltha.core.config.config_backend import EtcdStore

+

+# KV store uses this prefix to store resource info

+PATH_PREFIX = 'resource_manager/{}'

+

+

+class ResourceKvStore(object):

+    """Implements apis to store/get/remove resource in backend store."""

+

+    def __init__(self, technology, device_id, backend, host, port):

+        """

+        Create ResourceKvStore object.

+

+        Based on backend ('consul' and 'etcd' use the host and port

+        to create the respective object.

+

+        :param technology: PON technology

+        :param device_id: OLT device id

+        :param backend: Type of backend storage (etcd or consul)

+        :param host: host ip info for backend storage

+        :param port: port for the backend storage

+        :raises exception when invalid backend store passed as an argument

+        """

+        # logger

+        self._log = structlog.get_logger()

+

+        path = PATH_PREFIX.format(technology)

+        try:

+            if backend == 'consul':

+                self._kv_store = ConsulStore(host, port, path)

+            elif backend == 'etcd':

+                self._kv_store = EtcdStore(host, port, path)

+            else:

+                self._log.error('Invalid-backend')

+                raise Exception("Invalid-backend-for-kv-store")

+        except Exception as e:

+            self._log.exception("exception-in-init")

+            raise Exception(e)

+

+    def update_to_kv_store(self, path, resource):

+        """

+        Update resource.

+

+        :param path: path to update the resource

+        :param resource: updated resource

+        """

+        try:

+            self._kv_store[path] = str(resource)

+            self._log.debug("Resource-updated-in-kv-store", path=path)

+            return True

+        except BaseException:

+            self._log.exception("Resource-update-in-kv-store-failed",

+                                path=path, resource=resource)

+        return False

+

+    def get_from_kv_store(self, path):

+        """

+        Get resource.

+

+        :param path: path to get the resource

+        """

+        resource = None

+        try:

+            resource = self._kv_store[path]

+            self._log.debug("Got-resource-from-kv-store", path=path)

+        except KeyError:

+            self._log.info("Resource-not-found-updating-resource",

+                           path=path)

+        except BaseException:

+            self._log.exception("Getting-resource-from-kv-store-failed",

+                                path=path)

+        return resource

+

+    def remove_from_kv_store(self, path):

+        """

+        Remove resource.

+

+        :param path: path to remove the resource

+        """

+        try:

+            del self._kv_store[path]

+            self._log.debug("Resource-deleted-in-kv-store", path=path)

+            return True

+        except BaseException:

+            self._log.exception("Resource-delete-in-kv-store-failed",

+                                path=path)

+        return False

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..17b2871
--- /dev/null
+++ b/python/common/pon_resource_manager/resource_manager.py
@@ -0,0 +1,677 @@
+#
+# 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 structlog
+from bitstring import BitArray
+from ast import literal_eval
+import shlex
+from argparse import ArgumentParser, ArgumentError
+
+from common.pon_resource_manager.resource_kv_store import ResourceKvStore
+
+
+# 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
+    ONU_ID = 'ONU_ID'
+    ALLOC_ID = 'ALLOC_ID'
+    GEMPORT_ID = 'GEMPORT_ID'
+
+    # The resource ranges for a given device vendor_type should be placed
+    # at 'resource_manager/<technology>/resource_ranges/<olt_vendor_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,
+        "pon_ports": 16
+    }
+
+    '''
+    # constants used as keys to reference the resource range parameters from
+    # and external KV store.
+    ONU_START_IDX = "onu_id_start"
+    ONU_END_IDX = "onu_id_end"
+    ALLOC_ID_START_IDX = "alloc_id_start"
+    ALLOC_ID_END_IDX = "alloc_id_end"
+    GEM_PORT_ID_START_IDX = "gemport_id_start"
+    GEM_PORT_ID_END_IDX = "gemport_id_end"
+    NUM_OF_PON_PORT = "pon_ports"
+
+    # PON Resource range configuration on the KV store.
+    # Format: 'resource_manager/<technology>/resource_ranges/<olt_vendor_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/{}'
+
+    # 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'
+
+    # 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_vendor = None
+            self._kv_store = ResourceKvStore(technology, device_id, backend,
+                                             host, port)
+            # Below attribute, pon_resource_ranges, should be initialized
+            # by reading from KV store.
+            self.pon_resource_ranges = dict()
+        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_vendor = self._get_olt_vendor()
+        # Try to initialize the PON Resource Ranges from KV store based on the
+        # OLT vendor key, if available
+        if self.olt_vendor is None:
+            self._log.info("olt-vendor-unavailable--not-reading-from-kv-store")
+            return False
+
+        path = self.PON_RESOURCE_RANGE_CONFIG_PATH.format(self.olt_vendor)
+        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:
+                self.pon_resource_ranges = json.loads(resource_range_config)
+                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 init_default_pon_resource_ranges(self, onu_start_idx=1,
+                                         onu_end_idx=127,
+                                         alloc_id_start_idx=1024,
+                                         alloc_id_end_idx=2816,
+                                         gem_port_id_start_idx=1024,
+                                         gem_port_id_end_idx=8960,
+                                         num_of_pon_ports=16):
+        """
+        Initialize default PON resource ranges
+
+        :param onu_start_idx: onu id start index
+        :param onu_end_idx: onu id end index
+        :param alloc_id_start_idx: alloc id start index
+        :param alloc_id_end_idx: alloc id end index
+        :param gem_port_id_start_idx: gemport id start index
+        :param gem_port_id_end_idx: gemport id end index
+        :param num_of_pon_ports: number of PON ports
+        """
+        self._log.info("initialize-default-resource-range-values")
+        self.pon_resource_ranges[
+            PONResourceManager.ONU_START_IDX] = onu_start_idx
+        self.pon_resource_ranges[PONResourceManager.ONU_END_IDX] = onu_end_idx
+        self.pon_resource_ranges[
+            PONResourceManager.ALLOC_ID_START_IDX] = alloc_id_start_idx
+        self.pon_resource_ranges[
+            PONResourceManager.ALLOC_ID_END_IDX] = alloc_id_end_idx
+        self.pon_resource_ranges[
+            PONResourceManager.GEM_PORT_ID_START_IDX] = gem_port_id_start_idx
+        self.pon_resource_ranges[
+            PONResourceManager.GEM_PORT_ID_END_IDX] = gem_port_id_end_idx
+        self.pon_resource_ranges[
+            PONResourceManager.NUM_OF_PON_PORT] = num_of_pon_ports
+
+    def init_device_resource_pool(self):
+        """
+        Initialize resource pool for all PON ports.
+        """
+        i = 0
+        while i < self.pon_resource_ranges[PONResourceManager.NUM_OF_PON_PORT]:
+            self.init_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.ONU_ID,
+                start_idx=self.pon_resource_ranges[
+                    PONResourceManager.ONU_START_IDX],
+                end_idx=self.pon_resource_ranges[
+                    PONResourceManager.ONU_END_IDX])
+
+            i += 1
+
+        # TODO: ASFvOLT16 platform requires alloc and gemport ID to be unique
+        # across OLT. To keep it simple, a single pool (POOL 0) is maintained
+        # for both the resource types. This may need to change later.
+        self.init_resource_id_pool(
+            pon_intf_id=0,
+            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])
+
+        self.init_resource_id_pool(
+            pon_intf_id=0,
+            resource_type=PONResourceManager.GEMPORT_ID,
+            start_idx=self.pon_resource_ranges[
+                PONResourceManager.GEM_PORT_ID_START_IDX],
+            end_idx=self.pon_resource_ranges[
+                PONResourceManager.GEM_PORT_ID_END_IDX])
+
+    def clear_device_resource_pool(self):
+        """
+        Clear resource pool of all PON ports.
+        """
+        i = 0
+        while i < self.pon_resource_ranges[PONResourceManager.NUM_OF_PON_PORT]:
+            self.clear_resource_id_pool(
+                pon_intf_id=i,
+                resource_type=PONResourceManager.ONU_ID,
+            )
+            i += 1
+
+        self.clear_resource_id_pool(
+            pon_intf_id=0,
+            resource_type=PONResourceManager.ALLOC_ID,
+        )
+
+        self.clear_resource_id_pool(
+            pon_intf_id=0,
+            resource_type=PONResourceManager.GEMPORT_ID,
+        )
+
+    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
+        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 get_resource_id(self, pon_intf_id, resource_type, num_of_id=1):
+        """
+        Create alloc/gemport/onu 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
+
+        # TODO: ASFvOLT16 platform requires alloc and gemport ID to be unique
+        # across OLT. To keep it simple, a single pool (POOL 0) is maintained
+        # for both the resource types. This may need to change later.
+        # Override the incoming pon_intf_id to PON0
+        if resource_type == PONResourceManager.GEMPORT_ID or \
+                resource_type == PONResourceManager.ALLOC_ID:
+            pon_intf_id = 0
+
+        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:
+                result = self._generate_next_id(resource)
+            elif resource is not None and (
+                    resource_type == PONResourceManager.GEMPORT_ID or
+                    resource_type == PONResourceManager.ALLOC_ID):
+                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 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
+
+        # TODO: ASFvOLT16 platform requires alloc and gemport ID to be unique
+        # across OLT. To keep it simple, a single pool (POOL 0) is maintained
+        # for both the resource types. This may need to change later.
+        # Override the incoming pon_intf_id to PON0
+        if resource_type == PONResourceManager.GEMPORT_ID or \
+                resource_type == PONResourceManager.ALLOC_ID:
+            pon_intf_id = 0
+
+        path = self._get_path(pon_intf_id, resource_type)
+        if path is None:
+            return status
+
+        try:
+            resource = self._get_resource(path)
+            if resource is not None and resource_type == \
+                    PONResourceManager.ONU_ID:
+                self._release_id(resource, release_content)
+            elif resource is not None and (
+                    resource_type == PONResourceManager.ALLOC_ID or
+                    resource_type == PONResourceManager.GEMPORT_ID):
+                for content in release_content:
+                    self._release_id(resource, content)
+            else:
+                raise Exception("get-resource-failed")
+
+            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
+        """
+        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
+        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)
+
+        # 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)
+
+    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
+        """
+        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
+        """
+
+        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 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
+        """
+        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
+        """
+        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 _get_olt_vendor(self):
+        """
+        Get olt vendor variant
+
+        :return: type of olt vendor
+        """
+        olt_vendor = None
+        if self.extra_args and len(self.extra_args) > 0:
+            parser = OltVendorArgumentParser(add_help=False)
+            parser.add_argument('--olt_vendor', '-o', action='store',
+                                choices=['default', 'asfvolt16', 'cigolt24'],
+                                default='default')
+            try:
+                args = parser.parse_args(shlex.split(self.extra_args))
+                self._log.debug('parsing-extra-arguments', args=args)
+                olt_vendor = args.olt_vendor
+            except ArgumentError as e:
+                self._log.exception('invalid-arguments: {}', e=e)
+            except Exception as e:
+                self._log.exception('option-parsing-error: {}', e=e)
+
+        return olt_vendor
+
+    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
+        """
+        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)
+        else:
+            self._log.error("invalid-resource-pool-identifier")
+        return path
+
+    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)