# Copyright 2022-2025 ETSI SDG TeraFlowSDN (TFS) (https://tfs.etsi.org/) # # 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. import grpc import logging from common.Constants import ServiceNameEnum from common.Settings import get_service_host, get_service_port_grpc from common.proto.qkd_app_pb2 import App, AppId, AppList from common.proto.qkd_app_pb2_grpc import AppServiceStub from common.tools.client.RetryDecorator import retry, delay_exponential from common.tools.grpc.Tools import grpc_message_to_json_string LOGGER = logging.getLogger(__name__) # Define retry mechanism MAX_RETRIES = 15 DELAY_FUNCTION = delay_exponential(initial=0.01, increment=2.0, maximum=5.0) class QKDAppClient: def __init__(self, host=None, port=None): self.host = host or get_service_host(ServiceNameEnum.QKD_APP) self.port = port or get_service_port_grpc(ServiceNameEnum.QKD_APP) self.endpoint = f'{self.host}:{self.port}' LOGGER.debug(f'Initializing gRPC client to {self.endpoint}...') self.channel = None self.stub = None self.connect() def connect(self): try: self.channel = grpc.insecure_channel(self.endpoint) self.stub = AppServiceStub(self.channel) LOGGER.debug(f'gRPC channel to {self.endpoint} established successfully') except Exception as e: LOGGER.error(f"Failed to establish gRPC connection: {e}") self.stub = None def close(self): if self.channel: self.channel.close() LOGGER.debug(f'gRPC channel to {self.endpoint} closed') self.channel = None self.stub = None def check_connection(self): if self.stub is None: LOGGER.error("gRPC connection is not established. Retrying...") self.connect() if self.stub is None: raise ConnectionError("gRPC connection could not be established.") @retry(max_retries=MAX_RETRIES, delay_function=DELAY_FUNCTION) def RegisterApp(self, app_request: App) -> None: """Register a new QKD app.""" self.check_connection() LOGGER.debug(f'RegisterApp request: {grpc_message_to_json_string(app_request)}') self.stub.RegisterApp(app_request) LOGGER.debug('App registered successfully') @retry(max_retries=MAX_RETRIES, delay_function=DELAY_FUNCTION) def UpdateApp(self, app_request: App) -> None: """Update an existing QKD app.""" self.check_connection() LOGGER.debug(f'UpdateApp request: {grpc_message_to_json_string(app_request)}') self.stub.UpdateApp(app_request) LOGGER.debug('App updated successfully') @retry(max_retries=MAX_RETRIES, delay_function=DELAY_FUNCTION) def ListApps(self, context_id) -> AppList: """List all apps for a given context.""" self.check_connection() LOGGER.debug(f'ListApps request for context_id: {grpc_message_to_json_string(context_id)}') response = self.stub.ListApps(context_id) LOGGER.debug(f'ListApps result: {grpc_message_to_json_string(response)}') return response @retry(max_retries=MAX_RETRIES, delay_function=DELAY_FUNCTION) def GetApp(self, app_id: AppId) -> App: """Fetch details of a specific app by its ID.""" self.check_connection() LOGGER.debug(f'GetApp request for app_id: {grpc_message_to_json_string(app_id)}') response = self.stub.GetApp(app_id) LOGGER.debug(f'GetApp result: {grpc_message_to_json_string(response)}') return response @retry(max_retries=MAX_RETRIES, delay_function=DELAY_FUNCTION) def DeleteApp(self, app_id: AppId) -> None: """Delete an app by its ID.""" self.check_connection() # Ensures connection is established LOGGER.debug(f'DeleteApp request for app_id: {grpc_message_to_json_string(app_id)}') self.stub.DeleteApp(app_id) # Calls the gRPC service LOGGER.debug('App deleted successfully')