[PMSH] Read subscription API by Name

Issue-ID: DCAEGEN2-2818

Signed-off-by: Raviteja, Karumuri <raviteja.karumuri@est.tech>
Change-Id: Ie6925b4f4111e6f50c3b7dcd8eba670b89e63de3

9 files changed, 144 insertions, 114 deletions

diff --git a/components/pm-subscription-handler/Changelog.md b/components/pm-subscription-handler/Changelog.md
index 5fe19ba0..f02fc5eb 100755
--- a/components/pm-subscription-handler/Changelog.md
+++ b/components/pm-subscription-handler/Changelog.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 * Created Schema definitions in swagger file according to the new structure (DCAEGEN2-2889)
 * Implemented Create Subscription public API (DCAEGEN2-2819)
 * Added 2 new attributes to the subscription model (DCAEGEN2-2913)
+* Read subscription API by using subscription name (DCAEGEN2-2818)
 
 ## [1.3.2]
 ### Changed
diff --git a/components/pm-subscription-handler/pmsh_service/mod/api/controller.py b/components/pm-subscription-handler/pmsh_service/mod/api/controller.py
index 8af6c777..80d86362 100755
--- a/components/pm-subscription-handler/pmsh_service/mod/api/controller.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/api/controller.py
@@ -16,7 +16,6 @@
 # SPDX-License-Identifier: Apache-2.0
 # ============LICENSE_END=====================================================
 
-from mod.subscription import Subscription
 from http import HTTPStatus
 from mod import logger
 from mod.api.services import subscription_service
@@ -37,16 +36,6 @@ def status():
     return {'status': 'healthy'}
 
 
-def get_all_sub_to_nf_relations():
-    """ Retrieves all subscription to nf relations
-
-    Returns:
-        list: of Subscriptions and it's related Network Functions, else empty
-    """
-    subs_dict = [s.serialize() for s in Subscription.get_all()]
-    return subs_dict
-
-
 def post_subscription(body):
     """
     Creates a subscription
@@ -76,3 +65,34 @@ def post_subscription(body):
                      exc_info=True)
         response = e.invalid_message, HTTPStatus.BAD_REQUEST.value
     return response
+
+
+def get_subscription_by_name(subscription_name):
+    """
+    Retrieves subscription based on the name
+
+    Args:
+        subscription_name (String): Name of the subscription.
+
+    Returns:
+       success: dict of single Subscription, 200
+       None: subscription not defined, 404
+       Exception: Details about exception, 500
+    """
+    logger.info('API call received to fetch subscription by name')
+    try:
+        subscription = subscription_service.get_subscription_by_name(subscription_name)
+        if subscription is not None:
+            logger.info(f'subscription object with the name "{subscription_name}" '
+                        'was fetched successfully from database')
+            return subscription.serialize(), HTTPStatus.OK
+        else:
+            logger.error(f'subscription object with the name "{subscription_name}" '
+                         'was un successful to fetch from database')
+            return {'error': 'Subscription was not defined with the name : '
+                             f'{subscription_name}'}, HTTPStatus.NOT_FOUND
+    except Exception as exception:
+        logger.error(f'The following exception occurred "{exception}" while fetching subscription '
+                     f'with the name "{subscription_name}"')
+        return {'error': 'Request was not processed due to Exception : '
+                         f'{exception}'}, HTTPStatus.INTERNAL_SERVER_ERROR
diff --git a/components/pm-subscription-handler/pmsh_service/mod/api/db_models.py b/components/pm-subscription-handler/pmsh_service/mod/api/db_models.py
index 49ca0581..96a803ba 100755
--- a/components/pm-subscription-handler/pmsh_service/mod/api/db_models.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/api/db_models.py
@@ -38,7 +38,7 @@ class SubscriptionModel(db.Model):
     network_filter = relationship(
         'NetworkFunctionFilterModel',
         cascade='all, delete-orphan',
-        backref='subscription')
+        backref='subscription', uselist=False)
 
     measurement_groups = relationship(
         'MeasurementGroupModel',
@@ -63,14 +63,12 @@ class SubscriptionModel(db.Model):
         return False
 
     def serialize(self):
-        sub_nfs = NfSubRelationalModel.query.filter(
-            NfSubRelationalModel.subscription_name == self.subscription_name).all()
-        db.session.remove()
-        return {'subscription_name': self.subscription_name,
-                'operational_policy_name': self.operational_policy_name,
-                'control_loop_name': self.control_loop_name,
-                'subscription_status': self.status,
-                'network_functions': [sub_nf.serialize_nf() for sub_nf in sub_nfs]}
+        return {'subscription': {'subscriptionName': self.subscription_name,
+                                 'operationalPolicyName': self.operational_policy_name,
+                                 'controlLoopName': self.control_loop_name,
+                                 'nfFilter': self.network_filter.serialize(),
+                                 'measurementGroups':
+                                     [mg.serialize() for mg in self.measurement_groups]}}
 
 
 class NetworkFunctionModel(db.Model):
@@ -141,7 +139,7 @@ class NfSubRelationalModel(db.Model):
 
     def __repr__(self):
         return f'subscription_name: {self.subscription_name}, ' \
-            f'nf_name: {self.nf_name}, nf_sub_status: {self.nf_sub_status}'
+               f'nf_name: {self.nf_name}, nf_sub_status: {self.nf_sub_status}'
 
     def serialize(self):
         return {'subscription_name': self.subscription_name, 'nf_name': self.nf_name,
@@ -185,12 +183,11 @@ class NetworkFunctionFilterModel(db.Model):
 
     def __repr__(self):
         return f'subscription_name: {self.subscription_name}, ' \
-            f'nf_names: {self.nf_names}, model_invariant_ids: {self.model_invariant_ids}' \
+               f'nf_names: {self.nf_names}, model_invariant_ids: {self.model_invariant_ids}' \
                f'model_version_ids: {self.model_version_ids}, model_names: {self.model_names}'
 
     def serialize(self):
-        return {'subscriptionName': self.subscription_name,
-                'nfNames': convert_db_string_to_list(self.nf_names),
+        return {'nfNames': convert_db_string_to_list(self.nf_names),
                 'modelInvariantIDs': convert_db_string_to_list(self.model_invariant_ids),
                 'modelVersionIDs': convert_db_string_to_list(self.model_version_ids),
                 'modelNames': convert_db_string_to_list(self.model_names)}
@@ -231,13 +228,12 @@ class MeasurementGroupModel(db.Model):
                f'managed_object_dns_basic: {self.managed_object_dns_basic}'
 
     def serialize(self):
-        return {'subscription_name': self.subscription_name,
-                'measurement_group_name': self.measurement_group_name,
-                'administrative_state': self.administrative_state,
-                'file_based_gp': self.file_based_gp,
-                'file_location': self.file_location,
-                'measurement_type': self.measurement_type,
-                'managed_object_dns_basic': self.managed_object_dns_basic}
+        return {'measurementGroup': {'measurementGroupName': self.measurement_group_name,
+                                     'administrativeState': self.administrative_state,
+                                     'fileBasedGP': self.file_based_gp,
+                                     'fileLocation': self.file_location,
+                                     'measurementTypes': self.measurement_type,
+                                     'managedObjectDNsBasic': self.managed_object_dns_basic}}
 
 
 class NfMeasureGroupRelationalModel(db.Model):
@@ -267,7 +263,7 @@ class NfMeasureGroupRelationalModel(db.Model):
 
     def __repr__(self):
         return f'measurement_grp_name: {self.measurement_grp_name}, ' \
-            f'nf_name: {self.nf_name}, nf_measure_grp_status: {self.nf_measure_grp_status}'
+               f'nf_name: {self.nf_name}, nf_measure_grp_status: {self.nf_measure_grp_status}'
 
 
 def convert_db_string_to_list(db_string):
diff --git a/components/pm-subscription-handler/pmsh_service/mod/api/pmsh_swagger.yml b/components/pm-subscription-handler/pmsh_service/mod/api/pmsh_swagger.yml
index 11cea4ee..f27fb7ab 100644
--- a/components/pm-subscription-handler/pmsh_service/mod/api/pmsh_swagger.yml
+++ b/components/pm-subscription-handler/pmsh_service/mod/api/pmsh_swagger.yml
@@ -31,46 +31,6 @@ schemes:
   - http
 # Paths supported by the server application
 paths:
-  /subscriptions:
-    get:
-      description: >-
-        Get all defined Subscriptions and their related Network Functions from ONAP.
-      operationId: mod.api.controller.get_all_sub_to_nf_relations
-      responses:
-        200:
-          description: OK; Array of subscriptions are returned as an object
-          schema:
-            type: array
-            items:
-              type: object
-              properties:
-                subscription_name:
-                  type: string
-                  description: Name of the Subscription
-                subscription_status:
-                  type: string
-                  description: Status of the Subscription
-                network_functions:
-                  type: array
-                  items:
-                    type: object
-                    properties:
-                      nf_name:
-                        type: string
-                        description: Name of the Network Function
-                      nf_sub_status:
-                        type: string
-                        description: Status of the Subscription on the Network Function
-                      orchestration_status:
-                        type: string
-                        description: Orchestration status of the Network Function
-        401:
-          description: Unauthorized
-        403:
-          description: Forbidden
-        404:
-          description: there are no subscriptions defined
-
   /healthcheck:
     get:
       operationId: mod.api.controller.status
@@ -112,6 +72,28 @@ paths:
         400:
           description: Invalid input
 
+  /subscription/{subscription_name}:
+    get:
+      description: Get the Subscription from ONAP specified by Name
+      operationId: mod.api.controller.get_subscription_by_name
+      tags:
+        - "Subscription"
+      parameters:
+        - name: subscription_name
+          in: path
+          required: true
+          description: Name of the subscription
+          type: string
+      responses:
+        200:
+          description: OK; Requested Subscription was returned
+          schema:
+            $ref : "#/definitions/subscription"
+        404:
+          description: Subscription with specified name not found
+        500:
+          description: Exception occurs while querying database
+
 definitions:
   subscription:
     type: object
diff --git a/components/pm-subscription-handler/pmsh_service/mod/api/services/subscription_service.py b/components/pm-subscription-handler/pmsh_service/mod/api/services/subscription_service.py
index ea1640c2..c41bb18b 100644
--- a/components/pm-subscription-handler/pmsh_service/mod/api/services/subscription_service.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/api/services/subscription_service.py
@@ -23,6 +23,7 @@ from mod.api.services import measurement_group_service, nf_service
 from mod.api.custom_exception import InvalidDataException, DuplicateDataException
 from mod.subscription import AdministrativeState
 from sqlalchemy.exc import IntegrityError
+from sqlalchemy.orm import joinedload
 
 
 def create_subscription(subscription):
@@ -203,7 +204,7 @@ def save_subscription_request(subscription):
         subscription (dict): subscription request to be saved.
 
     Returns:
-        string: Subscription name
+        SubscriptionModel: subscription object which was added to the session
         list[MeasurementGroupModel]: list of measurement groups
     """
     logger.info(f'Saving subscription request for: {subscription["subscriptionName"]}')
@@ -289,3 +290,22 @@ def save_nf_filter(nf_filter, subscription_name):
                                             model_version_ids=nf_filter['modelVersionIDs'],
                                             model_names=nf_filter['modelNames'])
     db.session.add(new_filter)
+
+
+def get_subscription_by_name(subscription_name):
+    """
+    Retrieves the subscription information by name
+
+    Args:
+        subscription_name (String): Name of the Subscription
+
+    Returns:
+        SubscriptionModel: If subscription was defined else None
+    """
+    logger.info(f'Attempting to fetch subscription by name: {subscription_name}')
+    subscription_model = db.session.query(SubscriptionModel) \
+        .options(joinedload(SubscriptionModel.network_filter),
+                 joinedload(SubscriptionModel.measurement_groups)) \
+        .filter_by(subscription_name=subscription_name).first()
+    db.session.remove()
+    return subscription_model
diff --git a/components/pm-subscription-handler/pmsh_service/mod/subscription.py b/components/pm-subscription-handler/pmsh_service/mod/subscription.py
index bdfed189..603343f0 100755
--- a/components/pm-subscription-handler/pmsh_service/mod/subscription.py
+++ b/components/pm-subscription-handler/pmsh_service/mod/subscription.py
@@ -202,18 +202,6 @@ class Subscription:
         db.session.remove()
         return sub_model.status
 
-    @staticmethod
-    def get_all():
-        """ Retrieves a list of subscriptions
-
-        Returns:
-            list(SubscriptionModel): Subscriptions list else empty
-        """
-
-        sub_models = SubscriptionModel.query.all()
-        db.session.remove()
-        return sub_models
-
     def create_subscription_on_nfs(self, nfs, mr_pub):
         """ Publishes an event to create a Subscription on an nf
 
diff --git a/components/pm-subscription-handler/tests/base_setup.py b/components/pm-subscription-handler/tests/base_setup.py
index e422ceac..4328f59c 100755
--- a/components/pm-subscription-handler/tests/base_setup.py
+++ b/components/pm-subscription-handler/tests/base_setup.py
@@ -15,12 +15,14 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 # ============LICENSE_END=====================================================
+import copy
 import json
 import os
 from unittest import TestCase
 from unittest.mock import patch, MagicMock
 
 from mod import create_app, db
+from mod.api.db_models import NetworkFunctionFilterModel, MeasurementGroupModel, SubscriptionModel
 from mod.network_function import NetworkFunctionFilter
 from mod.pmsh_utils import AppConfig
 from mod.pmsh_config import AppConfig as NewAppConfig
@@ -31,6 +33,24 @@ def get_pmsh_config(file_path='data/cbs_data_1.json'):
         return json.load(data)
 
 
+def subscription_data(subscription_name):
+    nf_filter = NetworkFunctionFilterModel(subscription_name, '{^pnf.*,^vnf.*}',
+                                           '{}', '{}', '{}')
+    mg_first = MeasurementGroupModel(subscription_name, 'MG1', 'UNLOCKED', 15, '/pm/pm.xml',
+                                     '[{ "measurementType": "countera" }, '
+                                     '{ "measurementType": "counterb" }]',
+                                     '[{ "DN":"dna"},{"DN":"dnb"}]')
+    mg_second = copy.deepcopy(mg_first)
+    mg_second.measurement_group_name = 'MG2'
+    mg_second.administrative_state = 'LOCKED'
+    mg_list = [mg_first, mg_second]
+    subscription_model = SubscriptionModel(subscription_name, 'pmsh_operational_policy',
+                                           'pmsh_control_loop_name', 'LOCKED')
+    subscription_model.network_filter = nf_filter
+    subscription_model.measurement_groups = mg_list
+    return subscription_model
+
+
 class BaseClassSetup(TestCase):
     app = None
     app_context = None
diff --git a/components/pm-subscription-handler/tests/test_controller.py b/components/pm-subscription-handler/tests/test_controller.py
index a3a28163..7bd72a29 100755
--- a/components/pm-subscription-handler/tests/test_controller.py
+++ b/components/pm-subscription-handler/tests/test_controller.py
@@ -18,14 +18,15 @@
 import json
 import os
 from unittest.mock import patch, MagicMock
-import responses
-from requests import Session
+from http import HTTPStatus
+
 from mod import aai_client
-from mod.api.controller import status, get_all_sub_to_nf_relations, post_subscription
+from mod.api.controller import status, post_subscription, get_subscription_by_name
 from tests.base_setup import BaseClassSetup
 from mod.api.db_models import SubscriptionModel, NfMeasureGroupRelationalModel
 from mod.subscription import SubNfState
 from mod.network_function import NetworkFunctionFilter
+from tests.base_setup import subscription_data
 
 
 class ControllerTestCase(BaseClassSetup):
@@ -55,26 +56,6 @@ class ControllerTestCase(BaseClassSetup):
     def test_status_response_healthy(self):
         self.assertEqual(status()['status'], 'healthy')
 
-    @patch.object(Session, 'get')
-    @patch.object(Session, 'put')
-    def test_get_all_sub_to_nf_relations(self, mock_put_session, mock_get_session):
-        mock_put_session.return_value.status_code = 200
-        mock_put_session.return_value.text = self.aai_response_data
-        mock_get_session.return_value.status_code = 200
-        mock_get_session.return_value.text = self.good_model_info
-        responses.add(responses.GET,
-                      'https://aai:8443/aai/v20/service-design-and-creation/models/model/'
-                      '7129e420-d396-4efb-af02-6b83499b12f8/model-vers/model-ver/'
-                      'e80a6ae3-cafd-4d24-850d-e14c084a5ca9',
-                      json=json.loads(self.good_model_info), status=200)
-        self.xnfs = aai_client.get_pmsh_nfs_from_aai(self.app_conf, self.app_conf.nf_filter)
-        sub_model = self.app_conf.subscription.get()
-        for nf in self.xnfs:
-            self.app_conf.subscription.add_network_function_to_subscription(nf, sub_model)
-        all_subs = get_all_sub_to_nf_relations()
-        self.assertEqual(len(all_subs[0]['network_functions']), 3)
-        self.assertEqual(all_subs[0]['subscription_name'], 'ExtraPM-All-gNB-R2B')
-
     def create_test_subs(self, new_sub_name, new_msrmt_grp_name):
         subscription = self.subscription_request.replace('ExtraPM-All-gNB-R2B', new_sub_name)
         subscription = subscription.replace('msrmt_grp_name', new_msrmt_grp_name)
@@ -129,3 +110,31 @@ class ControllerTestCase(BaseClassSetup):
         response = post_subscription(subscription)
         self.assertEqual(response[1], 400)
         self.assertEqual(response[0], 'No value provided in subscription name')
+
+    @patch('mod.api.services.subscription_service.get_subscription_by_name',
+           MagicMock(return_value=subscription_data('sub_demo')))
+    def test_get_subscription_by_name_api(self):
+        sub, status_code = get_subscription_by_name('sub_demo')
+        self.assertEqual(status_code, HTTPStatus.OK)
+        self.assertEqual(sub['subscription']['subscriptionName'], 'sub_demo')
+        self.assertEqual(sub['subscription']['nfFilter']['nfNames'],
+                         ['^pnf.*', '^vnf.*'])
+        self.assertEqual(sub['subscription']['controlLoopName'],
+                         'pmsh_control_loop_name')
+        self.assertEqual(len(sub['subscription']['measurementGroups']), 2)
+        self.assertEqual(sub['subscription']['operationalPolicyName'],
+                         'pmsh_operational_policy')
+
+    @patch('mod.api.services.subscription_service.get_subscription_by_name',
+           MagicMock(return_value=None))
+    def test_get_subscription_by_name_api_error(self):
+        sub, status_code = get_subscription_by_name('sub_demo')
+        self.assertEqual(status_code, HTTPStatus.NOT_FOUND)
+        self.assertEqual(sub['error'],
+                         'Subscription was not defined with the name : sub_demo')
+
+    @patch('mod.api.services.subscription_service.get_subscription_by_name',
+           MagicMock(side_effect=Exception('something failed')))
+    def test_get_subscription_by_name_api_exception(self):
+        sub, status_code = get_subscription_by_name('sub_demo')
+        self.assertEqual(status_code, HTTPStatus.INTERNAL_SERVER_ERROR)
diff --git a/components/pm-subscription-handler/tests/test_subscription.py b/components/pm-subscription-handler/tests/test_subscription.py
index 538baf39..5c40c4fd 100755
--- a/components/pm-subscription-handler/tests/test_subscription.py
+++ b/components/pm-subscription-handler/tests/test_subscription.py
@@ -75,12 +75,6 @@ class SubscriptionTest(BaseClassSetup):
         self.app_conf.subscription.add_network_function_to_subscription(list(self.xnfs)[1],
                                                                         self.sub_model)
 
-    def test_create_existing_subscription(self):
-        sub1 = self.app_conf.subscription.create()
-        same_sub1 = self.app_conf.subscription.create()
-        self.assertEqual(sub1, same_sub1)
-        self.assertEqual(1, len(self.app_conf.subscription.get_all()))
-
     def test_add_duplicate_network_functions_per_subscription(self):
         self.app_conf.subscription.add_network_function_to_subscription(list(self.xnfs)[0],
                                                                         self.sub_model)