Adding AAI client and apply filter

	# Adding Subscription class
	# Adding MR and Utils helper classes

Signed-off-by: efiacor <fiachra.corcoran@est.tech>
Change-Id: I791b506d8cf166737d67cef22052852256f8a811
Issue-ID: DCAEGEN2-1930

1 files changed, 170 insertions, 0 deletions

diff --git a/components/pm-subscription-handler/pmsh_service/mod/pmsh_utils.py b/components/pm-subscription-handler/pmsh_service/mod/pmsh_utils.py
new file mode 100755
index 00000000..b665691d
--- /dev/null
+++ b/components/pm-subscription-handler/pmsh_service/mod/pmsh_utils.py
@@ -0,0 +1,170 @@
+# ============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 uuid
+
+import requests
+from requests.auth import HTTPBasicAuth
+
+import mod.pmsh_logging as logger
+
+
+class AppConfig:
+    def __init__(self, **kwargs):
+        self.aaf_creds = {'aaf_id': kwargs.get('aaf_identity'),
+                          'aaf_pass': kwargs.get('aaf_password')}
+        self.cert_path = kwargs.get('cert_path')
+        self.key_path = kwargs.get('key_path')
+        self.streams_subscribes = kwargs.get('streams_subscribes')
+        self.streams_publishes = kwargs.get('streams_publishes')
+
+    def get_mr_sub(self, sub_name):
+        """
+        Returns the MrSub object requested.
+
+        Args:
+            sub_name: the key of the subscriber object.
+
+        Returns:
+            MrSub: an Instance of an `MrSub` <MrSub> Object.
+
+        Raises:
+            KeyError: if the sub_name is not found.
+        """
+        try:
+            return _MrSub(sub_name, self.aaf_creds, **self.streams_subscribes[sub_name])
+        except KeyError as e:
+            logger.debug(e)
+            raise
+
+    def get_mr_pub(self, pub_name):
+        """
+        Returns the MrPub object requested.
+
+        Args:
+            pub_name: the key of the publisher object.
+
+        Returns:
+            MrPub: an Instance of an `MrPub` <MrPub> Object.
+
+        Raises:
+            KeyError: if the sub_name is not found.
+        """
+        try:
+            return _MrPub(pub_name, self.aaf_creds, **self.streams_publishes[pub_name])
+        except KeyError as e:
+            logger.debug(e)
+            raise
+
+    @property
+    def cert_params(self):
+        """
+        Returns the tls artifact paths.
+
+        Returns:
+            cert_path, key_path: the path to tls cert and key.
+        """
+        return self.cert_path, self.key_path
+
+
+class _DmaapMrClient:
+    def __init__(self, aaf_creds, **kwargs):
+        """
+        A DMaaP Message Router utility class.
+        Sub classes should be invoked via the AppConfig.get_mr_{pub|sub} only.
+        Args:
+            aaf_creds: a dict of aaf secure credentials.
+            **kwargs: a dict of streams_{subscribes|publishes} data.
+        """
+        self.topic_url = kwargs.get('dmaap_info').get('topic_url')
+        self.aaf_id = aaf_creds.get('aaf_id')
+        self.aaf_pass = aaf_creds.get('aaf_pass')
+
+
+class _MrPub(_DmaapMrClient):
+    def __init__(self, pub_name, aaf_creds, **kwargs):
+        self.pub_name = pub_name
+        super().__init__(aaf_creds, **kwargs)
+
+    def publish_to_topic(self, event_json):
+        """
+        Publish the event to the DMaaP Message Router topic.
+
+        Args:
+            event_json: the json data to be published.
+
+        Raises:
+            Exception: if post request fails.
+        """
+        try:
+            session = requests.Session()
+            headers = {'content-type': 'application/json', 'x-transactionId': str(uuid.uuid1())}
+            response = session.post(self.topic_url, headers=headers,
+                                    auth=HTTPBasicAuth(self.aaf_id, self.aaf_pass), json=event_json,
+                                    verify=False)
+            response.raise_for_status()
+        except Exception as e:
+            logger.debug(e)
+            raise
+
+    def publish_subscription_event_data(self, subscription, xnf_name):
+        """
+        Update the Subscription dict with xnf and policy name then publish to DMaaP MR topic.
+
+        Args:
+            subscription: the `Subscription` <Subscription> object.
+            xnf_name: the xnf to include in the event.
+        """
+        try:
+            subscription_event = subscription.prepare_subscription_event(xnf_name)
+            self.publish_to_topic(subscription_event)
+        except Exception as e:
+            logger.debug(f'pmsh_utils.publish_subscription_event_data : {e}')
+
+
+class _MrSub(_DmaapMrClient):
+    def __init__(self, sub_name, aaf_creds, **kwargs):
+        self.sub_name = sub_name
+        super().__init__(aaf_creds, **kwargs)
+
+    def get_from_topic(self, consumer_id, consumer_group='dcae_pmsh_cg', timeout=1000):
+        """
+        Returns the json data from the MrTopic.
+
+        Args:
+            consumer_id: Within your subscribers group, a name that uniquely
+            identifies your subscribers process.
+            consumer_group: A name that uniquely identifies your subscribers.
+            timeout: The request timeout value in mSec.
+
+        Returns:
+            list[str]: the json response from DMaaP Message Router topic, else None.
+        """
+        topic_data = None
+        try:
+            session = requests.Session()
+            headers = {'accept': 'application/json', 'content-type': 'application/json'}
+            response = session.get(f'{self.topic_url}/{consumer_group}/{consumer_id}'
+                                   f'?timeout={timeout}',
+                                   auth=HTTPBasicAuth(self.aaf_id, self.aaf_pass), headers=headers,
+                                   verify=False)
+            response.raise_for_status()
+            if response.ok:
+                topic_data = response.json()
+        except Exception as e:
+            logger.debug(e)
+        return topic_data