--- /dev/null
+# ============LICENSE_START===================================================
+# Copyright (C) 2019-2020 Nordix 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.
+#
+# SPDX-License-Identifier: Apache-2.0
+# ============LICENSE_END=====================================================
+
+import json
+from os import environ
+
+import requests
+from tenacity import retry, wait_fixed, stop_after_attempt
+
+from pmsh_service.mod import pmsh_logging as logger
+
+
+class ConfigHandler:
+ """ Handles retrieval of PMSH's configuration from Configbinding service."""
+
+ def __init__(self):
+ self.cbs_url = f'http://{self.cbs_hostname}:{str(self.cbs_port)}/' \
+ f'service_component_all/{self.hostname}'
+ self._config = None
+
+ @property
+ def cbs_hostname(self):
+ return _get_environment_variable('CONFIG_BINDING_SERVICE_SERVICE_HOST')
+
+ @property
+ def cbs_port(self):
+ return _get_environment_variable('CONFIG_BINDING_SERVICE_SERVICE_PORT')
+
+ @property
+ def hostname(self):
+ return _get_environment_variable('HOSTNAME')
+
+ @retry(wait=wait_fixed(2), stop=stop_after_attempt(5))
+ def get_config(self):
+ """ Retrieves PMSH's configuration from Configbinding service. If a non-2xx response
+ is received, it retries after 2 seconds for 5 times before raising an exception.
+
+ Returns:
+ dict: Dictionary representation of the the service configuration
+
+ Raises:
+ Exception: If any error occurred pulling configuration from Configbinding service.
+ """
+ if self._config is None:
+ logger.debug('No configuration found, pulling from Configbinding Service.')
+ try:
+ response = requests.get(self.cbs_url)
+ response.raise_for_status()
+ self._config = response.json()
+ logger.debug(f'PMSH Configuration from Configbinding Service: {self._config}')
+ return json.loads(self._config)
+ except Exception as err:
+ raise Exception(f'Error retrieving configuration from CBS: {err}')
+ else:
+ return self._config
+
+
+def _get_environment_variable(env_var_key):
+ try:
+ env_var = environ[env_var_key]
+ except KeyError as error:
+ raise KeyError(f'Environment variable {env_var_key} must be set. {error}')
+ return env_var
--- /dev/null
+# ============LICENSE_START===================================================
+# Copyright (C) 2019-2020 Nordix 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.
+#
+# SPDX-License-Identifier: Apache-2.0
+# ============LICENSE_END=====================================================
+
+import json
+import unittest
+from os import environ
+from os import path
+from unittest.mock import patch
+
+import requests
+import responses
+from tenacity import wait_none
+
+from pmsh_service.mod.config_handler import ConfigHandler
+
+
+class ConfigHandlerTest(unittest.TestCase):
+
+ def setUp(self):
+ self.env_vars = {'CONFIG_BINDING_SERVICE_SERVICE_HOST': 'cbs_hostname',
+ 'CONFIG_BINDING_SERVICE_SERVICE_PORT': '10000',
+ 'HOSTNAME': 'hostname'}
+ for key, value in self.env_vars.items():
+ environ[key] = value
+ self.cbs_url = 'http://cbs_hostname:10000/service_component_all/hostname'
+ self.expected_config = self._get_expected_config()
+
+ def test_missing_environment_variable(self):
+ for key, value in self.env_vars.items():
+ with self.assertRaises(KeyError):
+ environ.pop(key)
+ test_value = globals()[value]
+ test_value()
+ environ[key] = value
+
+ @responses.activate
+ def test_get_config_success(self):
+ responses.add(responses.GET, self.cbs_url, json=json.dumps(self.expected_config),
+ status=200)
+
+ config_handler = ConfigHandler()
+ config_handler.get_config.retry.wait = wait_none()
+
+ self.assertEqual(self.expected_config, config_handler.get_config())
+
+ def test_get_config_already_exists(self):
+ config_handler = ConfigHandler()
+ expected_config = self._get_expected_config()
+ config_handler._config = expected_config
+
+ with patch.object(requests, 'get') as mock_get_request:
+ actual_config = config_handler.get_config()
+
+ self.assertEqual(0, mock_get_request.call_count)
+ self.assertEqual(expected_config, actual_config)
+
+ @responses.activate
+ def test_get_config_error(self):
+ responses.add(responses.GET, self.cbs_url, status=404)
+ config_handler = ConfigHandler()
+ config_handler.get_config.retry.wait = wait_none()
+
+ with self.assertRaises(Exception):
+ config_handler.get_config()
+
+ @responses.activate
+ def test_get_config_max_retries_error(self):
+ retry_limit = 5
+ config_handler = ConfigHandler()
+ config_handler.get_config.retry.wait = wait_none()
+
+ for __ in range(retry_limit):
+ responses.add(responses.GET, self.cbs_url, status=500)
+
+ with self.assertRaises(Exception):
+ config_handler.get_config()
+ self.assertEqual(retry_limit, len(responses.calls))
+
+ @responses.activate
+ def test_get_config_less_than_5_retries_success(self):
+ retry_attempts = 4
+ responses.add(responses.GET, self.cbs_url, status=500)
+ responses.add(responses.GET, self.cbs_url, status=400)
+ responses.add(responses.GET, self.cbs_url, status=300)
+ responses.add(responses.GET, self.cbs_url, json=json.dumps(self.expected_config),
+ status=200)
+
+ config_handler = ConfigHandler()
+ config_handler.get_config.retry.wait = wait_none()
+ config_handler.get_config()
+
+ self.assertEqual(retry_attempts, len(responses.calls))
+
+ @staticmethod
+ def _get_expected_config():
+ with open(path.join(path.dirname(__file__), 'expected_config.json'))as json_file:
+ return json.load(json_file)