| # |
| # 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 zlib import decompress |
| |
| import grpc |
| 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, \ |
| VolthaGlobalServiceStub |
| from google.protobuf import empty_pb2 |
| from google.protobuf.json_format import MessageToDict, ParseDict |
| from google.protobuf import descriptor |
| import base64 |
| import math |
| |
| _INT64_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_INT64, |
| descriptor.FieldDescriptor.CPPTYPE_UINT64]) |
| _FLOAT_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_FLOAT, |
| descriptor.FieldDescriptor.CPPTYPE_DOUBLE]) |
| _INFINITY = 'Infinity' |
| _NEG_INFINITY = '-Infinity' |
| _NAN = 'NaN' |
| |
| 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 = voltha_pb2.VolthaLocalServiceStub(self.channel) |
| # self.global_stub = voltha_pb2.VolthaGlobalServiceStub(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(1, 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 |
| |
| # TODO: should be generated code |
| # Focus for now is issuing a GET request for VolthaGlobalService or VolthaLocalService |
| @inlineCallbacks |
| def invoke_voltha_api(self, key): |
| # TODO: This should be part of a parameter request |
| depth = [('get-depth', '-1')] |
| try: |
| data = {} |
| req = ParseDict(data, empty_pb2.Empty()) |
| service_method = key.split('-') |
| service = service_method[0] |
| method = service_method[1] |
| if service == 'VolthaGlobalService': |
| stub = VolthaGlobalServiceStub |
| elif service == 'VolthaLocalService': |
| stub = VolthaLocalServiceStub |
| else: |
| raise # Exception |
| |
| log.info('voltha-rpc', service=service, method=method, req=req, |
| depth=depth) |
| |
| res, metadata = yield self.invoke(stub, method, req, depth) |
| |
| # returnValue(MessageToDict(res, True, True)) |
| returnValue(self.convertToDict(res)) |
| |
| except Exception, e: |
| log.error('failure', exception=repr(e)) |
| |
| @inlineCallbacks |
| def invoke(self, stub, method_name, request, metadata, retry=1): |
| """ |
| Invoke a gRPC call to the remote server and return the response. |
| :param stub: Reference to the *_pb2 service stub |
| :param method_name: The method name inside the service stub |
| :param request: The request protobuf message |
| :param metadata: [(str, str), (str, str), ...] |
| :return: The response protobuf message and returned trailing metadata |
| """ |
| |
| if not self.connected: |
| raise ServiceUnavailable() |
| |
| try: |
| method = getattr(stub(self.channel), method_name) |
| response, rendezvous = method.with_call(request, metadata=metadata) |
| returnValue((response, rendezvous.trailing_metadata())) |
| |
| except grpc._channel._Rendezvous, e: |
| code = e.code() |
| if code == grpc.StatusCode.UNAVAILABLE: |
| e = ServiceUnavailable() |
| |
| if self.connected: |
| self.connected = False |
| yield self.connect() |
| if retry > 0: |
| response = yield self.invoke(stub, method_name, |
| request, metadata, |
| retry=retry - 1) |
| returnValue(response) |
| |
| elif code in ( |
| grpc.StatusCode.NOT_FOUND, |
| grpc.StatusCode.INVALID_ARGUMENT, |
| grpc.StatusCode.ALREADY_EXISTS): |
| |
| pass # don't log error, these occur naturally |
| |
| else: |
| log.exception(e) |
| |
| raise e |
| |
| # Below is an adaptation of Google's MessageToDict() which includes |
| # protobuf options extensions |
| |
| class Error(Exception): |
| """Top-level module error for json_format.""" |
| |
| class SerializeToJsonError(Error): |
| """Thrown if serialization to JSON fails.""" |
| |
| def _IsMapEntry(self, field): |
| return (field.type == descriptor.FieldDescriptor.TYPE_MESSAGE and |
| field.message_type.has_options and |
| field.message_type.GetOptions().map_entry) |
| |
| def convertToDict(self, message): |
| """Converts message to an object according to Proto3 JSON Specification.""" |
| |
| js = {} |
| return self._RegularMessageToJsonObject(message, js) |
| |
| def get_yang_option(self, field): |
| opt = field.GetOptions() |
| yang_opt = {} |
| for fd, val in opt.ListFields(): |
| if fd.full_name == 'voltha.yang_inline_node': |
| yang_opt['id'] = val.id |
| yang_opt['type'] = val.type |
| # Fow now, a max of 1 yang option is set per field |
| return yang_opt |
| |
| def _RegularMessageToJsonObject(self, message, js): |
| """Converts normal message according to Proto3 JSON Specification.""" |
| fields = message.ListFields() |
| |
| try: |
| for field, value in fields: |
| # Check for options |
| yang_opt = self.get_yang_option(field) |
| |
| name = field.name |
| if self._IsMapEntry(field): |
| # Convert a map field. |
| v_field = field.message_type.fields_by_name['value'] |
| js_map = {} |
| for key in value: |
| if isinstance(key, bool): |
| if key: |
| recorded_key = 'true' |
| else: |
| recorded_key = 'false' |
| else: |
| recorded_key = key |
| js_map[recorded_key] = self._FieldToJsonObject( |
| v_field, value[key]) |
| js[name] = js_map |
| elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED: |
| # Convert a repeated field. |
| js[name] = [self._FieldToJsonObject(field, k) |
| for k in value] |
| else: |
| # This specific yang option applies only to non-repeated |
| # fields |
| if yang_opt: # Create a map |
| js_map = {} |
| js_map['yang_field_option'] = True |
| js_map['yang_field_option_id'] = yang_opt['id'] |
| js_map['yang_field_option_type'] = yang_opt['type'] |
| js_map['name'] = name |
| js_map[name] = self._FieldToJsonObject(field, value) |
| js[name] = js_map |
| else: |
| js[name] = self._FieldToJsonObject(field, value) |
| |
| # Serialize default value if including_default_value_fields is True. |
| message_descriptor = message.DESCRIPTOR |
| for field in message_descriptor.fields: |
| # Singular message fields and oneof fields will not be affected. |
| if (( |
| field.label != descriptor.FieldDescriptor.LABEL_REPEATED and |
| field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE) or |
| field.containing_oneof): |
| continue |
| name = field.name |
| if name in js: |
| # Skip the field which has been serailized already. |
| continue |
| if self._IsMapEntry(field): |
| js[name] = {} |
| elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED: |
| js[name] = [] |
| else: |
| js[name] = self._FieldToJsonObject(field, |
| field.default_value) |
| |
| except ValueError as e: |
| raise self.SerializeToJsonError( |
| 'Failed to serialize {0} field: {1}.'.format(field.name, e)) |
| |
| return js |
| |
| def _FieldToJsonObject(self, field, value): |
| """Converts field value according to Proto3 JSON Specification.""" |
| if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE: |
| return self.convertToDict(value) |
| elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_ENUM: |
| enum_value = field.enum_type.values_by_number.get(value, None) |
| if enum_value is not None: |
| return enum_value.name |
| else: |
| raise self.SerializeToJsonError('Enum field contains an ' |
| 'integer value ' |
| 'which can not mapped to an enum value.') |
| elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_STRING: |
| if field.type == descriptor.FieldDescriptor.TYPE_BYTES: |
| # Use base64 Data encoding for bytes |
| return base64.b64encode(value).decode('utf-8') |
| else: |
| return value |
| elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_BOOL: |
| return bool(value) |
| elif field.cpp_type in _INT64_TYPES: |
| return str(value) |
| elif field.cpp_type in _FLOAT_TYPES: |
| if math.isinf(value): |
| if value < 0.0: |
| return _NEG_INFINITY |
| else: |
| return _INFINITY |
| if math.isnan(value): |
| return _NAN |
| return value |