Pull config from CBS

Signed-off-by: emartin <ephraim.martin@est.tech>
Issue-ID: DCAEGEN2-1843
Change-Id: Id97960dc02aca5531be016d70ea388473b556683

6 files changed, 262 insertions, 3 deletions

diff --git a/components/pm-subscription-handler/pmsh_service/mod/config_handler.py b/components/pm-subscription-handler/pmsh_service/mod/config_handler.py
new file mode 100755
index 00000000..e9edbca4
--- /dev/null
+++ b/components/pm-subscription-handler/pmsh_service/mod/config_handler.py
@@ -0,0 +1,78 @@
+# ============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
diff --git a/components/pm-subscription-handler/pmsh_service/pmsh_service.py b/components/pm-subscription-handler/pmsh_service/pmsh_service.py
index 6764c75f..8832f570 100755
--- a/components/pm-subscription-handler/pmsh_service/pmsh_service.py
+++ b/components/pm-subscription-handler/pmsh_service/pmsh_service.py
@@ -1,5 +1,5 @@
 # ============LICENSE_START===================================================
-#  Copyright (C) 2019 Nordix Foundation.
+#  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.
diff --git a/components/pm-subscription-handler/setup.py b/components/pm-subscription-handler/setup.py
index 9012a04c..a4d9ada4 100644
--- a/components/pm-subscription-handler/setup.py
+++ b/components/pm-subscription-handler/setup.py
@@ -30,6 +30,5 @@ setup(
     python_requires='>=3',
     install_requires=[
         "requests==2.22.0",
-        "aiohttp==3.6.2",
-        "onappylog==1.0.9"],
+        "tenacity==6.0.0"],
 )
diff --git a/components/pm-subscription-handler/tests/config_handler_test.py b/components/pm-subscription-handler/tests/config_handler_test.py
new file mode 100755
index 00000000..fcc25d60
--- /dev/null
+++ b/components/pm-subscription-handler/tests/config_handler_test.py
@@ -0,0 +1,112 @@
+# ============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)
diff --git a/components/pm-subscription-handler/tests/expected_config.json b/components/pm-subscription-handler/tests/expected_config.json
new file mode 100755
index 00000000..43f67e88
--- /dev/null
+++ b/components/pm-subscription-handler/tests/expected_config.json
@@ -0,0 +1,68 @@
+{
+  "config":{},
+  "policy": {
+  "subscription": {
+    "subscriptionName": "someExtraPM-AllKista-gNB-R2B",
+    "administrativeState": "UNLOCKED",
+    "fileBasedGP": 15,
+    "fileLocation": "c:\/\/PM",
+    "nfTypeModelInvariantId": "2829292",
+    "nfFilter": {
+      "swVersions": [
+        "A21",
+        "B"
+      ],
+      "nfNames": [
+        "ABC",
+        "DEF",
+        "foo.*"
+      ]
+    },
+    "measurementGroups": [
+      {
+        "measurementGroup": {
+          "measurementTypes": [
+            {
+              "measurementType": "countera"
+            },
+            {
+              "measurementType": "counterb"
+            }
+          ],
+          "managedObjectDNsBasic": [
+            {
+              "DN": "dna"
+            },
+            {
+              "DN": "dnb"
+            }
+          ]
+        }
+      },
+      {
+        "measurementGroup": {
+          "measurementTypes": [
+            {
+              "measurementType": "counterc"
+            },
+            {
+              "measurementType": "counterd"
+            }
+          ],
+          "managedObjectDNsBasic": [
+            {
+              "DN": "dnc"
+            },
+            {
+              "DN": "dnd"
+            }
+          ]
+        }
+      }
+    ]
+  }
+}
+
+
+
+}
\ No newline at end of file
diff --git a/components/pm-subscription-handler/tox.ini b/components/pm-subscription-handler/tox.ini
index fcbb647c..523338d1 100644
--- a/components/pm-subscription-handler/tox.ini
+++ b/components/pm-subscription-handler/tox.ini
@@ -26,6 +26,7 @@ deps=
     pytest
     coverage
     pytest-cov
+    responses==0.10.7
 setenv =
     PYTHONPATH={toxinidir}/pmsh_service:{toxinidir}/pmsh_service/mod:{toxinidir}/tests
 commands=
@@ -39,3 +40,4 @@ commands = flake8 pmsh_service tests
 
 [flake8]
 max-line-length=100
+ignore = E999