This commit consists of:
1) Dockerizing the netconf server
2) Update proto2yang to support module imports
3) Provide a set of yang modules derived from the proto files in voltha.
These files as well as the slight mmodifications to the proto files are
provided in the experiments/netconf/proto2yang directory
4) Code to automatically pull proto files from voltha into the netconf server,
compiles them and produce the yang equivalent files.
5) Add a getvoltha netconf API to provide voltha state information (basic at
this time). There is potential to make this generic once we experiment
with additional APIs
Change-Id: I94f3a1f871b8025ad675d5f9b9b626d1be8b8d36
diff --git a/netconf/grpc_client/grpc_client.py b/netconf/grpc_client/grpc_client.py
new file mode 100644
index 0000000..ae19067
--- /dev/null
+++ b/netconf/grpc_client/grpc_client.py
@@ -0,0 +1,288 @@
+#
+# Copyright 2016 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.
+#
+
+"""
+gRPC client meant to connect to a gRPC server endpoint, and query the
+end-point's schema by calling SchemaService.Schema(Empty) and all of its
+semantics are derived from the recovered schema.
+"""
+
+import os
+import sys
+from random import randint
+from zlib import decompress
+
+import grpc
+from consul import Consul
+from grpc._channel import _Rendezvous
+from structlog import get_logger
+from twisted.internet import reactor
+from twisted.internet.defer import inlineCallbacks, returnValue
+from werkzeug.exceptions import ServiceUnavailable
+
+from common.utils.asleep import asleep
+from netconf.protos import third_party
+from netconf.protos.schema_pb2 import SchemaServiceStub
+from google.protobuf.empty_pb2 import Empty
+from common.utils.consulhelpers import get_endpoint_from_consul
+from netconf.protos.voltha_pb2 import VolthaLocalServiceStub
+from twisted.internet import threads
+from google.protobuf import empty_pb2
+from google.protobuf.json_format import MessageToDict, ParseDict
+from simplejson import dumps, load
+
+log = get_logger()
+
+
+class GrpcClient(object):
+ """
+ Connect to a gRPC server, fetch its schema, and process the downloaded
+ proto schema files. The goal is to convert the proto schemas into yang
+ schemas which would be exposed to the Netconf client.
+ """
+ RETRY_BACKOFF = [0.05, 0.1, 0.2, 0.5, 1, 2, 5]
+
+ def __init__(self, consul_endpoint, work_dir,
+ grpc_endpoint='localhost:50055',
+ reconnect_callback=None,
+ on_start_callback=None):
+ self.consul_endpoint = consul_endpoint
+ self.grpc_endpoint = grpc_endpoint
+ self.work_dir = work_dir
+ self.reconnect_callback = reconnect_callback
+ self.on_start_callback = on_start_callback
+
+ self.plugin_dir = os.path.abspath(os.path.join(
+ os.path.dirname(__file__), '../protoc_plugins'))
+
+ self.channel = None
+ self.local_stub = None
+ self.schema = None
+ self.retries = 0
+ self.shutting_down = False
+ self.connected = False
+
+ def start(self):
+ log.debug('starting')
+ if not self.connected:
+ reactor.callLater(0, self.connect)
+ log.info('started')
+ return self
+
+ def stop(self):
+ log.debug('stopping')
+ if self.shutting_down:
+ return
+ self.shutting_down = True
+ log.info('stopped')
+
+
+ def set_on_start_callback(self, on_start_callback):
+ self.on_start_callback = on_start_callback
+ return self
+
+
+ def set_reconnect_callback(self, reconnect_callback):
+ self.reconnect_callback = reconnect_callback
+ return self
+
+
+ def resolve_endpoint(self, endpoint):
+ ip_port_endpoint = endpoint
+ if endpoint.startswith('@'):
+ try:
+ ip_port_endpoint = get_endpoint_from_consul(
+ self.consul_endpoint, endpoint[1:])
+ log.info('endpoint-found',
+ endpoint=endpoint, ip_port=ip_port_endpoint)
+ except Exception as e:
+ log.error('service-not-found-in-consul', endpoint=endpoint,
+ exception=repr(e))
+ return None, None
+ if ip_port_endpoint:
+ host, port = ip_port_endpoint.split(':', 2)
+ return host, int(port)
+
+
+ @inlineCallbacks
+ def connect(self):
+ """
+ (Re-)Connect to end-point
+ """
+ if self.shutting_down or self.connected:
+ return
+
+ try:
+ host, port = self.resolve_endpoint(self.grpc_endpoint)
+
+ # If host and port is not set then we will retry
+ if host and port:
+ log.info('grpc-endpoint-connecting', host=host, port=port)
+ self.channel = grpc.insecure_channel('{}:{}'.format(host, port))
+
+ yang_from = self._retrieve_schema()
+ log.info('proto-to-yang-schema', file=yang_from)
+ self._compile_proto_files(yang_from)
+ self._clear_backoff()
+
+ if self.on_start_callback is not None:
+ reactor.callLater(0, self.on_start_callback)
+
+ self.connected = True
+ if self.reconnect_callback is not None:
+ reactor.callLater(0, self.reconnect_callback)
+
+ self.local_stub = VolthaLocalServiceStub(self.channel)
+
+ return
+
+ except _Rendezvous, e:
+ if e.code() == grpc.StatusCode.UNAVAILABLE:
+ log.info('grpc-endpoint-not-available')
+ else:
+ log.exception(e)
+ yield self._backoff('not-available')
+
+ except Exception, e:
+ if not self.shutting_down:
+ log.exception('cannot-connect', endpoint=_endpoint)
+ yield self._backoff('unknown-error')
+
+ reactor.callLater(0, self.connect)
+
+ def _backoff(self, msg):
+ wait_time = self.RETRY_BACKOFF[min(self.retries,
+ len(self.RETRY_BACKOFF) - 1)]
+ self.retries += 1
+ log.error(msg, retry_in=wait_time)
+ return asleep(wait_time)
+
+ def _clear_backoff(self):
+ if self.retries:
+ log.info('reconnected', after_retries=self.retries)
+ self.retries = 0
+
+ def _retrieve_schema(self):
+ """
+ Retrieve schema from gRPC end-point, and save all *.proto files in
+ the work directory.
+ """
+ assert isinstance(self.channel, grpc.Channel)
+ stub = SchemaServiceStub(self.channel)
+ # try:
+ schemas = stub.GetSchema(Empty())
+ # except _Rendezvous, e:
+ # if e.code == grpc.StatusCode.UNAVAILABLE:
+ #
+ # else:
+ # raise e
+
+ os.system('mkdir -p %s' % self.work_dir)
+ os.system('rm -fr /tmp/%s/*' %
+ self.work_dir.replace('/tmp/', '')) # safer
+
+ for proto_file in schemas.protos:
+ proto_fname = proto_file.file_name
+ # TODO: Do we need to process a set of files using a prefix
+ # instead of just one?
+ proto_content = proto_file.proto
+ log.info('saving-proto', fname=proto_fname, dir=self.work_dir,
+ length=len(proto_content))
+ with open(os.path.join(self.work_dir, proto_fname), 'w') as f:
+ f.write(proto_content)
+
+ desc_content = decompress(proto_file.descriptor)
+ desc_fname = proto_fname.replace('.proto', '.desc')
+ log.info('saving-descriptor', fname=desc_fname, dir=self.work_dir,
+ length=len(desc_content))
+ with open(os.path.join(self.work_dir, desc_fname), 'wb') as f:
+ f.write(desc_content)
+ return schemas.yang_from
+
+ def _compile_proto_files(self, yang_from):
+ """
+ For each *.proto file in the work directory, compile the proto
+ file into the respective *_pb2.py file as well as generate the
+ corresponding yang schema.
+ :return: None
+ """
+ log.info('start')
+ google_api_dir = os.path.abspath(os.path.join(
+ os.path.dirname(__file__), '../protos/third_party'
+ ))
+
+ log.info('google-api', api_dir=google_api_dir)
+
+ netconf_base_dir = os.path.abspath(os.path.join(
+ os.path.dirname(__file__), '../..'
+ ))
+ log.info('netconf-dir', dir=netconf_base_dir)
+
+
+ for fname in [f for f in os.listdir(self.work_dir)
+ if f.endswith('.proto')]:
+ log.info('filename', file=fname)
+
+ need_yang = fname == yang_from
+ log.debug('compiling',
+ file=fname,
+ yang_schema_required=need_yang)
+ cmd = (
+ 'cd %s && '
+ 'env PATH=%s PYTHONPATH=%s '
+ 'python -m grpc.tools.protoc '
+ '-I. '
+ '-I%s '
+ '--python_out=. '
+ '--grpc_python_out=. '
+ '--plugin=protoc-gen-custom=%s/proto2yang.py '
+ '%s'
+ '%s' % (
+ self.work_dir,
+ ':'.join([os.environ['PATH'], self.plugin_dir]),
+ ':'.join([google_api_dir, netconf_base_dir]),
+ google_api_dir,
+ self.plugin_dir,
+ '--custom_out=. ' if need_yang else '',
+ fname)
+ )
+ log.debug('executing', cmd=cmd, file=fname)
+ os.system(cmd)
+ log.info('compiled', file=fname)
+
+ # # test-load each _pb2 file to see all is right
+ # if self.work_dir not in sys.path:
+ # sys.path.insert(0, self.work_dir)
+ #
+ # for fname in [f for f in os.listdir(self.work_dir)
+ # if f.endswith('_pb2.py')]:
+ # modname = fname[:-len('.py')]
+ # log.debug('test-import', modname=modname)
+ # _ = __import__(modname)
+
+ #TODO: find a different way to test the generated yang files
+
+ @inlineCallbacks
+ def get_voltha_instance(self):
+ try:
+ res = yield threads.deferToThread(
+ self.local_stub.GetVolthaInstance, empty_pb2.Empty())
+
+ out_data = MessageToDict(res, True, True)
+ returnValue(out_data)
+ except Exception, e:
+ log.error('failure', exception=repr(e))
+