Initial commit moving openolt adapter from voltha-go to the new repo.
This version works with ponsim rather than openolt, this is temporary.
It is currently being fixed to work with openolt.

Change-Id: I34a800c98f050140b367e2d474b7aa8b79f34b9a
Signed-off-by: William Kurkian <wkurkian@cisco.com>
diff --git a/python/common/utils/__init__.py b/python/common/utils/__init__.py
new file mode 100644
index 0000000..b0fb0b2
--- /dev/null
+++ b/python/common/utils/__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/utils/asleep.py b/python/common/utils/asleep.py
new file mode 100644
index 0000000..10d1ce3
--- /dev/null
+++ b/python/common/utils/asleep.py
@@ -0,0 +1,31 @@
+#
+# 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.
+#
+
+""" Async sleep (asleep) method and other twisted goodies """
+
+from twisted.internet import reactor
+from twisted.internet.defer import Deferred
+
+
+def asleep(dt):
+    """
+    Async (event driven) wait for given time period (in seconds)
+    :param dt: Delay in seconds
+    :return: Deferred to be fired with value None when time expires.
+    """
+    d = Deferred()
+    reactor.callLater(dt, lambda: d.callback(None))
+    return d
diff --git a/python/common/utils/consulhelpers.py b/python/common/utils/consulhelpers.py
new file mode 100644
index 0000000..853143b
--- /dev/null
+++ b/python/common/utils/consulhelpers.py
@@ -0,0 +1,178 @@
+#
+# 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.
+#
+
+"""
+Some consul related convenience functions
+"""
+
+from structlog import get_logger
+from consul import Consul
+from random import randint
+from nethelpers import get_my_primary_local_ipv4
+
+log = get_logger()
+
+
+def connect_to_consult(consul_endpoint):
+    log.debug('getting-service-endpoint', consul=consul_endpoint)
+
+    host = consul_endpoint.split(':')[0].strip()
+    port = int(consul_endpoint.split(':')[1].strip())
+
+    return Consul(host=host, port=port)
+
+
+def verify_all_services_healthy(consul_endpoint, service_name=None,
+                                number_of_expected_services=None):
+    """
+    Verify in consul if any service is healthy
+    :param consul_endpoint: a <host>:<port> string
+    :param service_name: name of service to check, optional
+    :param number_of_expected_services number of services to check for, optional
+    :return: true if healthy, false otherwise
+    """
+
+    def check_health(service):
+        _, serv_health = consul.health.service(service, passing=True)
+        return not serv_health == []
+
+    consul = connect_to_consult(consul_endpoint)
+
+    if service_name is not None:
+        return check_health(service_name)
+
+    services = get_all_services(consul_endpoint)
+
+    items = services.keys()
+
+    if number_of_expected_services is not None and \
+                    len(items) != number_of_expected_services:
+        return False
+
+    for item in items:
+        if not check_health(item):
+            return False
+
+    return True
+
+
+def get_all_services(consul_endpoint):
+    log.debug('getting-service-verify-health')
+
+    consul = connect_to_consult(consul_endpoint)
+    _, services = consul.catalog.services()
+
+    return services
+
+
+def get_all_instances_of_service(consul_endpoint, service_name):
+    log.debug('getting-all-instances-of-service', service=service_name)
+
+    consul = connect_to_consult(consul_endpoint)
+    _, services = consul.catalog.service(service_name)
+
+    for service in services:
+        log.debug('service',
+                  name=service['ServiceName'],
+                  serviceid=service['ServiceID'],
+                  serviceport=service['ServicePort'],
+                  createindex=service['CreateIndex'])
+
+    return services
+
+
+def get_endpoint_from_consul(consul_endpoint, service_name):
+    """
+    Get endpoint of service_name from consul.
+    :param consul_endpoint: a <host>:<port> string
+    :param service_name: name of service for which endpoint
+                         needs to be found.
+    :return: service endpoint if available, else exit.
+    """
+    log.debug('getting-service-info', service=service_name)
+
+    consul = connect_to_consult(consul_endpoint)
+    _, services = consul.catalog.service(service_name)
+
+    if len(services) == 0:
+        raise Exception(
+            'Cannot find service {} in consul'.format(service_name))
+        os.exit(1)
+
+    """ Get host IPV4 address
+    """
+    local_ipv4 = get_my_primary_local_ipv4()
+    """ If host IP address from where the request came in matches
+        the IP address of the requested service's host IP address,
+        pick the endpoint
+    """
+    for i in range(len(services)):
+        service = services[i]
+        if service['ServiceAddress'] == local_ipv4:
+            log.debug("picking address locally")
+            endpoint = '{}:{}'.format(service['ServiceAddress'],
+                                      service['ServicePort'])
+            return endpoint
+
+    """ If service is not available locally, picak a random
+        endpoint for the service from the list
+    """
+    service = services[randint(0, len(services) - 1)]
+    endpoint = '{}:{}'.format(service['ServiceAddress'],
+                              service['ServicePort'])
+
+    return endpoint
+
+
+def get_healthy_instances(consul_endpoint, service_name=None,
+                          number_of_expected_services=None):
+    """
+    Verify in consul if any service is healthy
+    :param consul_endpoint: a <host>:<port> string
+    :param service_name: name of service to check, optional
+    :param number_of_expected_services number of services to check for, optional
+    :return: true if healthy, false otherwise
+    """
+
+    def check_health(service):
+        _, serv_health = consul.health.service(service, passing=True)
+        return not serv_health == []
+
+    consul = connect_to_consult(consul_endpoint)
+
+    if service_name is not None:
+        return check_health(service_name)
+
+    services = get_all_services(consul_endpoint)
+
+    items = services.keys()
+
+    if number_of_expected_services is not None and \
+                    len(items) != number_of_expected_services:
+        return False
+
+    for item in items:
+        if not check_health(item):
+            return False
+
+    return True
+
+
+if __name__ == '__main__':
+    # print get_endpoint_from_consul('10.100.198.220:8500', 'kafka')
+    # print get_healthy_instances('10.100.198.220:8500', 'voltha-health')
+    # print get_healthy_instances('10.100.198.220:8500')
+    get_all_instances_of_service('10.100.198.220:8500', 'voltha-grpc')
diff --git a/python/common/utils/deferred_utils.py b/python/common/utils/deferred_utils.py
new file mode 100644
index 0000000..3c55c1a
--- /dev/null
+++ b/python/common/utils/deferred_utils.py
@@ -0,0 +1,56 @@
+# 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.
+from twisted.internet import reactor
+from twisted.internet.defer import Deferred
+from twisted.internet.error import AlreadyCalled
+
+
+class TimeOutError(Exception): pass
+
+
+class DeferredWithTimeout(Deferred):
+    """
+    Deferred with a timeout. If neither the callback nor the errback method
+    is not called within the given time, the deferred's errback will be called
+    with a TimeOutError() exception.
+
+    All other uses are the same as of Deferred().
+    """
+    def __init__(self, timeout=1.0):
+        Deferred.__init__(self)
+        self._timeout = timeout
+        self.timer = reactor.callLater(timeout, self.timed_out)
+
+    def timed_out(self):
+        self.errback(
+            TimeOutError('timed out after {} seconds'.format(self._timeout)))
+
+    def callback(self, result):
+        self._cancel_timer()
+        return Deferred.callback(self, result)
+
+    def errback(self, fail):
+        self._cancel_timer()
+        return Deferred.errback(self, fail)
+
+    def cancel(self):
+        self._cancel_timer()
+        return Deferred.cancel(self)
+
+    def _cancel_timer(self):
+        try:
+            self.timer.cancel()
+        except AlreadyCalled:
+            pass
+
diff --git a/python/common/utils/dockerhelpers.py b/python/common/utils/dockerhelpers.py
new file mode 100644
index 0000000..4620aef
--- /dev/null
+++ b/python/common/utils/dockerhelpers.py
@@ -0,0 +1,75 @@
+#
+# 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.
+#
+
+"""
+Some docker related convenience functions
+"""
+from datetime import datetime
+from concurrent.futures import ThreadPoolExecutor
+
+import os
+import socket
+from structlog import get_logger
+
+from docker import Client, errors
+
+
+docker_socket = os.environ.get('DOCKER_SOCK', 'unix://tmp/docker.sock')
+log = get_logger()
+
+def get_my_containers_name():
+    """
+    Return the docker containers name in which this process is running.
+    To look up the container name, we use the container ID extracted from the
+    $HOSTNAME environment variable (which is set by docker conventions).
+    :return: String with the docker container name (or None if any issue is
+             encountered)
+    """
+    my_container_id = os.environ.get('HOSTNAME', None)
+
+    try:
+        docker_cli = Client(base_url=docker_socket)
+        info = docker_cli.inspect_container(my_container_id)
+
+    except Exception, e:
+        log.exception('failed', my_container_id=my_container_id, e=e)
+        raise
+
+    name = info['Name'].lstrip('/')
+
+    return name
+
+def get_all_running_containers():
+    try:
+        docker_cli = Client(base_url=docker_socket)
+        containers = docker_cli.containers()
+
+    except Exception, e:
+        log.exception('failed', e=e)
+        raise
+
+    return containers
+
+def inspect_container(id):
+    try:
+        docker_cli = Client(base_url=docker_socket)
+        info = docker_cli.inspect_container(id)
+    except Exception, e:
+        log.exception('failed-inspect-container', id=id, e=e)
+        raise
+
+    return info
+
diff --git a/python/common/utils/grpc_utils.py b/python/common/utils/grpc_utils.py
new file mode 100644
index 0000000..8df630e
--- /dev/null
+++ b/python/common/utils/grpc_utils.py
@@ -0,0 +1,109 @@
+#
+# 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.
+#
+
+"""
+Utilities to handle gRPC server and client side code in a Twisted environment
+"""
+import structlog
+from concurrent.futures import Future
+from twisted.internet import reactor
+from twisted.internet.defer import Deferred
+from twisted.python.threadable import isInIOThread
+
+
+log = structlog.get_logger()
+
+
+def twisted_async(func):
+    """
+    This decorator can be used to implement a gRPC method on the twisted
+    thread, allowing asynchronous programming in Twisted while serving
+    a gRPC call.
+
+    gRPC methods normally are called on the futures.ThreadPool threads,
+    so these methods cannot directly use Twisted protocol constructs.
+    If the implementation of the methods needs to touch Twisted, it is
+    safer (or mandatory) to wrap the method with this decorator, which will
+    call the inner method from the external thread and ensure that the
+    result is passed back to the foreign thread.
+
+    Example usage:
+
+    When implementing a gRPC server, typical pattern is:
+
+    class SpamService(SpamServicer):
+
+        def GetBadSpam(self, request, context):
+            '''this is called from a ThreadPoolExecutor thread'''
+            # generally unsafe to make Twisted calls
+
+        @twisted_async
+        def GetSpamSafely(self, request, context):
+            '''this method now is executed on the Twisted main thread
+            # safe to call any Twisted protocol functions
+
+        @twisted_async
+        @inlineCallbacks
+        def GetAsyncSpam(self, request, context):
+            '''this generator can use inlineCallbacks Twisted style'''
+            result = yield some_async_twisted_call(request)
+            returnValue(result)
+
+    """
+    def in_thread_wrapper(*args, **kw):
+
+        if isInIOThread():
+
+            return func(*args, **kw)
+
+        f = Future()
+
+        def twisted_wrapper():
+            try:
+                d = func(*args, **kw)
+                if isinstance(d, Deferred):
+
+                    def _done(result):
+                        f.set_result(result)
+                        f.done()
+
+                    def _error(e):
+                        f.set_exception(e)
+                        f.done()
+
+                    d.addCallback(_done)
+                    d.addErrback(_error)
+
+                else:
+                    f.set_result(d)
+                    f.done()
+
+            except Exception, e:
+                f.set_exception(e)
+                f.done()
+
+        reactor.callFromThread(twisted_wrapper)
+        try:
+            result = f.result()
+        except Exception, e:
+            log.exception(e=e, func=func, args=args, kw=kw)
+            raise
+
+        return result
+
+    return in_thread_wrapper
+
+
diff --git a/python/common/utils/id_generation.py b/python/common/utils/id_generation.py
new file mode 100644
index 0000000..e0fea1c
--- /dev/null
+++ b/python/common/utils/id_generation.py
@@ -0,0 +1,116 @@
+#
+# 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
+
+
+BROADCAST_CORE_ID=hex(0xFFFF)[2:]
+
+def get_next_core_id(current_id_in_hex_str):
+    """
+    :param current_id_in_hex_str: a hex string of the maximum core id 
+    assigned without the leading 0x characters
+    :return: current_id_in_hex_str + 1 in hex string 
+    """
+    if not current_id_in_hex_str or current_id_in_hex_str == '':
+        return '0001'
+    else:
+        return format(int(current_id_in_hex_str, 16) + 1, '04x')
+
+
+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.
+    The returned logical device id  represents a 64 bits integer where the
+    lower 48 bits is the switch id and the upper 16 bits is the core id.   For
+    the datapath id the core id is set to '0000' as it is not used for voltha
+    core routing
+    :param core_id: string
+    :param switch_id:int
+    :return: cluster logical device id and OpenFlow datapath id
+    """
+    switch_id = format(switch_id, '012x')
+    core_in_hex=format(int(core_id, 16), '04x')
+    ld_id = '{}{}'.format(core_in_hex[-4:], switch_id[-12:])
+    dpid_id = '{}{}'.format('0000', switch_id[-12:])
+    return ld_id, int(dpid_id, 16)
+
+def is_broadcast_core_id(id):
+    assert id and len(id) == 16
+    return id[:4] == BROADCAST_CORE_ID
+
+def create_empty_broadcast_id():
+    """
+    Returns an empty broadcast id (ffff000000000000). The id is used to
+    dispatch xPON objects across all the Voltha instances.
+    :return: An empty broadcast id
+    """
+    return '{}{}'.format(BROADCAST_CORE_ID, '0'*12)
+
+def create_cluster_id():
+    """
+    Returns an id that is common across all voltha instances.  The id  
+    is a str of 64 bits.  The lower 48 bits refers to an id specific to that 
+    object while the upper 16 bits refers a broadcast core_id
+    :return: An common id across all Voltha instances
+    """
+    return '{}{}'.format(BROADCAST_CORE_ID, uuid4().hex[:12])
+
+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 len(device_id) == 16
+    # Get the leading 4 hexs and remove leading 0's
+    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 len(logical_device_id) == 16
+    # Get the leading 4 hexs and remove leading 0's
+    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 len(id_in_hex_str) > 12
+    return id_in_hex_str[:-12]
diff --git a/python/common/utils/indexpool.py b/python/common/utils/indexpool.py
new file mode 100644
index 0000000..858cb3a
--- /dev/null
+++ b/python/common/utils/indexpool.py
@@ -0,0 +1,64 @@
+# 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.
+from bitstring import BitArray
+import structlog
+
+log = structlog.get_logger()
+
+class IndexPool(object):
+    def __init__(self, max_entries, offset):
+        self.max_entries = max_entries
+        self.offset = offset
+        self.indices = BitArray(self.max_entries)
+
+    def get_next(self):
+        try:
+            _pos = self.indices.find('0b0')
+            self.indices.set(1, _pos)
+            return self.offset + _pos[0]
+        except IndexError:
+            log.info("exception-fail-to-allocate-id-all-bits-in-use")
+            return None
+
+    def allocate(self, index):
+        try:
+            _pos = index - self.offset
+            if not (0 <= _pos < self.max_entries):
+                log.info("{}-out-of-range".format(index))
+                return None
+            if self.indices[_pos]:
+                log.info("{}-is-already-allocated".format(index))
+                return None
+            self.indices.set(1, _pos)
+            return index
+
+        except IndexError:
+            return None
+
+    def release(self, index):
+        index -= self.offset
+        _pos = (index,)
+        try:
+            self.indices.set(0, _pos)
+        except IndexError:
+            log.info("bit-position-{}-out-of-range".format(index))
+
+    #index or multiple indices to set all of them to 1 - need to be a tuple
+    def pre_allocate(self, index):
+        if(isinstance(index, tuple)):
+            _lst = list(index)
+            for i in range(len(_lst)):
+                _lst[i] -= self.offset
+            index = tuple(_lst)
+            self.indices.set(1, index)
diff --git a/python/common/utils/json_format.py b/python/common/utils/json_format.py
new file mode 100644
index 0000000..c18d013
--- /dev/null
+++ b/python/common/utils/json_format.py
@@ -0,0 +1,105 @@
+# 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.
+"""
+Monkey patched json_format to allow best effort decoding of Any fields.
+Use the additional flag (strict_any_handling=False) to trigger the
+best-effort behavior. Omit the flag, or just use the original json_format
+module fot the strict behavior.
+"""
+
+from google.protobuf import json_format
+
+class _PatchedPrinter(json_format._Printer):
+
+    def __init__(self, including_default_value_fields=False,
+                 preserving_proto_field_name=False,
+                 strict_any_handling=False):
+        super(_PatchedPrinter, self).__init__(including_default_value_fields,
+                                              preserving_proto_field_name)
+        self.strict_any_handling = strict_any_handling
+
+    def _BestEffortAnyMessageToJsonObject(self, msg):
+        try:
+            res = self._AnyMessageToJsonObject(msg)
+        except TypeError:
+            res = self._RegularMessageToJsonObject(msg, {})
+        return res
+
+
+def MessageToDict(message,
+                  including_default_value_fields=False,
+                  preserving_proto_field_name=False,
+                  strict_any_handling=False):
+    """Converts protobuf message to a JSON dictionary.
+
+    Args:
+      message: The protocol buffers message instance to serialize.
+      including_default_value_fields: If True, singular primitive fields,
+          repeated fields, and map fields will always be serialized.  If
+          False, only serialize non-empty fields.  Singular message fields
+          and oneof fields are not affected by this option.
+      preserving_proto_field_name: If True, use the original proto field
+          names as defined in the .proto file. If False, convert the field
+          names to lowerCamelCase.
+      strict_any_handling: If True, converion will error out (like in the
+          original method) if an Any field with value for which the Any type
+          is not loaded is encountered. If False, the conversion will leave
+          the field un-packed, but otherwise will continue.
+
+    Returns:
+      A dict representation of the JSON formatted protocol buffer message.
+    """
+    printer = _PatchedPrinter(including_default_value_fields,
+                              preserving_proto_field_name,
+                              strict_any_handling=strict_any_handling)
+    # pylint: disable=protected-access
+    return printer._MessageToJsonObject(message)
+
+
+def MessageToJson(message,
+                  including_default_value_fields=False,
+                  preserving_proto_field_name=False,
+                  strict_any_handling=False):
+  """Converts protobuf message to JSON format.
+
+  Args:
+    message: The protocol buffers message instance to serialize.
+    including_default_value_fields: If True, singular primitive fields,
+        repeated fields, and map fields will always be serialized.  If
+        False, only serialize non-empty fields.  Singular message fields
+        and oneof fields are not affected by this option.
+    preserving_proto_field_name: If True, use the original proto field
+        names as defined in the .proto file. If False, convert the field
+        names to lowerCamelCase.
+    strict_any_handling: If True, converion will error out (like in the
+        original method) if an Any field with value for which the Any type
+        is not loaded is encountered. If False, the conversion will leave
+        the field un-packed, but otherwise will continue.
+
+  Returns:
+    A string containing the JSON formatted protocol buffer message.
+  """
+  printer = _PatchedPrinter(including_default_value_fields,
+                            preserving_proto_field_name,
+                            strict_any_handling=strict_any_handling)
+  return printer.ToJsonString(message)
+
+
+json_format._WKTJSONMETHODS['google.protobuf.Any'] = [
+    '_BestEffortAnyMessageToJsonObject',
+    '_ConvertAnyMessage'
+]
+
+json_format._Printer._BestEffortAnyMessageToJsonObject = \
+    json_format._Printer._AnyMessageToJsonObject
diff --git a/python/common/utils/message_queue.py b/python/common/utils/message_queue.py
new file mode 100644
index 0000000..2b4257a
--- /dev/null
+++ b/python/common/utils/message_queue.py
@@ -0,0 +1,89 @@
+#
+# 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.
+#
+from twisted.internet.defer import Deferred
+from twisted.internet.defer import succeed
+
+
+class MessageQueue(object):
+    """
+    An event driven queue, similar to twisted.internet.defer.DeferredQueue
+    but which allows selective dequeing based on a predicate function.
+    Unlike DeferredQueue, there is no limit on backlog, and there is no queue
+    limit.
+    """
+
+    def __init__(self):
+        self.waiting = []  # tuples of (d, predicate)
+        self.queue = []  # messages piling up here if no one is waiting
+
+    def reset(self):
+        """
+        Purge all content as well as waiters (by errback-ing their entries).
+        :return: None
+        """
+        for d, _ in self.waiting:
+            d.errback(Exception('mesage queue reset() was called'))
+        self.waiting = []
+        self.queue = []
+
+    def _cancelGet(self, d):
+        """
+        Remove a deferred from our waiting list.
+        :param d: The deferred that was been canceled.
+        :return: None
+        """
+        for i in range(len(self.waiting)):
+            if self.waiting[i][0] is d:
+                self.waiting.pop(i)
+
+    def put(self, obj):
+        """
+        Add an object to this queue
+        :param obj: arbitrary object that will be added to the queue
+        :return:
+        """
+
+        # if someone is waiting for this, return right away
+        for i in range(len(self.waiting)):
+            d, predicate = self.waiting[i]
+            if predicate is None or predicate(obj):
+                self.waiting.pop(i)
+                d.callback(obj)
+                return
+
+        # otherwise...
+        self.queue.append(obj)
+
+    def get(self, predicate=None):
+        """
+        Attempt to retrieve and remove an object from the queue that
+        matches the optional predicate.
+        :return: Deferred which fires with the next object available.
+        If predicate was provided, only objects for which
+        predicate(obj) is True will be considered.
+        """
+        for i in range(len(self.queue)):
+            msg = self.queue[i]
+            if predicate is None or predicate(msg):
+                self.queue.pop(i)
+                return succeed(msg)
+
+        # there were no matching entries if we got here, so we wait
+        d = Deferred(canceller=self._cancelGet)
+        self.waiting.append((d, predicate))
+        return d
+
+
diff --git a/python/common/utils/nethelpers.py b/python/common/utils/nethelpers.py
new file mode 100644
index 0000000..7df7f9f
--- /dev/null
+++ b/python/common/utils/nethelpers.py
@@ -0,0 +1,88 @@
+#
+# 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.
+#
+
+"""
+Some network related convenience functions
+"""
+
+from netifaces import AF_INET
+
+import netifaces as ni
+import netaddr
+
+
+def _get_all_interfaces():
+    m_interfaces = []
+    for iface in ni.interfaces():
+        m_interfaces.append((iface, ni.ifaddresses(iface)))
+    return m_interfaces
+
+
+def _get_my_primary_interface():
+    gateways = ni.gateways()
+    assert 'default' in gateways, \
+        ("No default gateway on host/container, "
+         "cannot determine primary interface")
+    default_gw_index = gateways['default'].keys()[0]
+    # gateways[default_gw_index] has the format (example):
+    # [('10.15.32.1', 'en0', True)]
+    interface_name = gateways[default_gw_index][0][1]
+    return interface_name
+
+
+def get_my_primary_local_ipv4(inter_core_subnet=None, ifname=None):
+    if not inter_core_subnet:
+        return _get_my_primary_local_ipv4(ifname)
+    # My IP should belong to the specified subnet
+    for iface in ni.interfaces():
+        addresses = ni.ifaddresses(iface)
+        if AF_INET in addresses:
+            m_ip = addresses[AF_INET][0]['addr']
+            _ip = netaddr.IPAddress(m_ip).value
+            m_network = netaddr.IPNetwork(inter_core_subnet)
+            if _ip >= m_network.first and _ip <= m_network.last:
+                return m_ip
+    return None
+
+
+def get_my_primary_interface(pon_subnet=None):
+    if not pon_subnet:
+        return _get_my_primary_interface()
+    # My interface should have an IP that belongs to the specified subnet
+    for iface in ni.interfaces():
+        addresses = ni.ifaddresses(iface)
+        if AF_INET in addresses:
+            m_ip = addresses[AF_INET][0]['addr']
+            m_ip = netaddr.IPAddress(m_ip).value
+            m_network = netaddr.IPNetwork(pon_subnet)
+            if m_ip >= m_network.first and m_ip <= m_network.last:
+                return iface
+    return None
+
+def mac_str_to_tuple(mac):
+    return tuple(int(d, 16) for d in mac.split(':'))
+
+def _get_my_primary_local_ipv4(ifname=None):
+    try:
+        ifname = get_my_primary_interface() if ifname is None else ifname
+        addresses = ni.ifaddresses(ifname)
+        ipv4 = addresses[AF_INET][0]['addr']
+        return ipv4
+    except Exception as e:
+        return None
+
+if __name__ == '__main__':
+    print get_my_primary_local_ipv4()
diff --git a/python/common/utils/ordered_weakvalue_dict.py b/python/common/utils/ordered_weakvalue_dict.py
new file mode 100644
index 0000000..9ea739a
--- /dev/null
+++ b/python/common/utils/ordered_weakvalue_dict.py
@@ -0,0 +1,48 @@
+#
+# 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.
+#
+from _weakref import ref
+from weakref import KeyedRef
+from collections import OrderedDict
+
+
+class OrderedWeakValueDict(OrderedDict):
+    """
+    Modified OrderedDict to use weak references as values. Entries disappear
+    automatically if the referred value has no more strong reference pointing
+    ot it.
+
+    Warning, this is not a complete implementation, only what is needed for
+    now. See test_ordered_wealvalue_dict.py to see what is tested behavior.
+    """
+    def __init__(self, *args, **kw):
+        def remove(wr, selfref=ref(self)):
+            self = selfref()
+            if self is not None:
+                super(OrderedWeakValueDict, self).__delitem__(wr.key)
+        self._remove = remove
+        super(OrderedWeakValueDict, self).__init__(*args, **kw)
+
+    def __setitem__(self, key, value):
+        super(OrderedWeakValueDict, self).__setitem__(
+            key, KeyedRef(value, self._remove, key))
+
+    def __getitem__(self, key):
+        o = super(OrderedWeakValueDict, self).__getitem__(key)()
+        if o is None:
+            raise KeyError, key
+        else:
+            return o
+
diff --git a/python/common/utils/registry.py b/python/common/utils/registry.py
new file mode 100644
index 0000000..270bd71
--- /dev/null
+++ b/python/common/utils/registry.py
@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+#
+# 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.
+#
+
+"""
+Simple component registry to provide centralized access to any registered
+components.
+"""
+from collections import OrderedDict
+from zope.interface import Interface
+
+
+class IComponent(Interface):
+    """
+    A Voltha Component
+    """
+
+    def start():
+        """
+        Called once the componet is instantiated. Can be used for async
+        initialization.
+        :return: (None or Deferred)
+        """
+
+    def stop():
+        """
+        Called once before the component is unloaded. Can be used for async
+        cleanup operations.
+        :return: (None or Deferred)
+        """
+
+
+class Registry(object):
+
+    def __init__(self):
+        self.components = OrderedDict()
+
+    def register(self, name, component):
+        assert IComponent.providedBy(component)
+        assert name not in self.components
+        self.components[name] = component
+        return component
+
+    def unregister(self, name):
+        if name in self.components:
+            del self.components[name]
+
+    def __call__(self, name):
+        return self.components[name]
+
+    def iterate(self):
+        return self.components.values()
+
+
+# public shared registry
+registry = Registry()