Add functionality to support NSI selection

Issue-ID: OPTFRA-677
Signed-off-by: krishnaa96 <krishna.moorthy6@wipro.com>
Change-Id: Ibc51e15fce4692a445df400053060d3a6977b4ce

4 files changed, 244 insertions, 0 deletions

diff --git a/apps/slice_selection/optimizers/__init__.py b/apps/slice_selection/optimizers/__init__.py
new file mode 100644
index 0000000..b45f74d
--- /dev/null
+++ b/apps/slice_selection/optimizers/__init__.py
@@ -0,0 +1,17 @@
+# -------------------------------------------------------------------------
+#   Copyright (C) 2020 Wipro Limited.
+#
+#   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.
+#
+# -------------------------------------------------------------------------
+#
diff --git a/apps/slice_selection/optimizers/conductor/__init__.py b/apps/slice_selection/optimizers/conductor/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/apps/slice_selection/optimizers/conductor/__init__.py
diff --git a/apps/slice_selection/optimizers/conductor/remote_opt_processor.py b/apps/slice_selection/optimizers/conductor/remote_opt_processor.py
new file mode 100644
index 0000000..a44fc4e
--- /dev/null
+++ b/apps/slice_selection/optimizers/conductor/remote_opt_processor.py
@@ -0,0 +1,104 @@
+# -------------------------------------------------------------------------
+#   Copyright (C) 2020 Wipro Limited.
+#
+#   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.
+#
+# -------------------------------------------------------------------------
+#
+
+"""
+Module for processing slice selection request
+"""
+
+import json
+import traceback
+from requests import RequestException
+
+from apps.slice_selection.optimizers.conductor.response_processor \
+    import conductor_response_processor, conductor_error_response_processor
+from osdf.adapters.conductor import conductor
+from osdf.adapters.policy.interface import get_policies
+from osdf.adapters.policy.utils import group_policies_gen
+from osdf.logging.osdf_logging import error_log, debug_log
+from osdf.utils.mdc_utils import mdc_from_json
+
+
+def process_nsi_selection_opt(request_json, osdf_config):
+    """Process the nsi selection request from API layer
+        :param request_json: api request
+        :param policies: flattened policies corresponding to this request
+        :param osdf_config: configuration specific to OSDF app
+        :return: response as a dictionary
+        """
+    req_info = request_json['requestInfo']
+    try:
+        mdc_from_json(request_json)
+
+        overall_recommendations = dict()
+        nst_info_map = dict()
+        for nst_info in request_json["NSTInfoList"]:
+            nst_name = nst_info["modelName"]
+            nst_info_map["nst_name"] = {"NSTName": nst_name,
+                                        "UUID": nst_info["modelVersionId"],
+                                        "invariantUUID": nst_info["modelInvariantId"]}
+
+            policy_request_json = request_json.copy()
+            policy_request_json['serviceInfo']['serviceName'] = nst_name
+
+            policies = get_policies(policy_request_json, "slice_selection")
+
+            demands = get_slice_demands(nst_name, policies, osdf_config.core)
+
+            request_parameters = {}
+            service_info = {}
+            req_info['numSolutions'] = 'all'
+            resp = conductor.request(req_info, demands, request_parameters, service_info, False,
+                                     osdf_config, policies)
+            debug_log.debug("Response from conductor {}".format(str(resp)))
+            overall_recommendations[nst_name] = resp["plans"][0].get("recommendations")
+
+        return conductor_response_processor(overall_recommendations, nst_info_map, req_info)
+
+    except Exception as ex:
+        error_log.error("Error for {} {}".format(req_info.get('requestId'),
+                                                 traceback.format_exc()))
+        if isinstance(ex, RequestException):
+            try:
+                error_message = json.loads(ex.response)['plans'][0]['message']
+            except Exception:
+                error_message = "Problem connecting to conductor"
+        else:
+            error_message = str(ex)
+        return conductor_error_response_processor(req_info, error_message)
+
+
+def get_slice_demands(model_name, policies, config):
+    """
+    :param model_name: model name of the slice
+    :param policies: flattened polcies corresponding to the request
+    :param config: configuration specific to OSDF app
+    :return: list of demands for the request
+    """
+    group_policies = group_policies_gen(policies, config)
+    subscriber_policy_list = group_policies["onap.policies.optimization.SubscriberPolicy"]
+    slice_demands = list()
+    for subscriber_policy in subscriber_policy_list:
+        policy_properties = subscriber_policy[list(subscriber_policy.keys())[0]]['properties']
+        if model_name in policy_properties["services"]:
+            subnet_attributes = policy_properties["properties"]["subscriberRole"][0]
+            for subnet in policy_properties["properties"]["subscriberName"]:
+                slice_demand = dict()
+                slice_demand["resourceModuleName"] = subnet
+                slice_demand['resourceModelInfo'] = subnet_attributes[subnet]
+                slice_demands.append(slice_demand)
+    return slice_demands
diff --git a/apps/slice_selection/optimizers/conductor/response_processor.py b/apps/slice_selection/optimizers/conductor/response_processor.py
new file mode 100644
index 0000000..5b7be01
--- /dev/null
+++ b/apps/slice_selection/optimizers/conductor/response_processor.py
@@ -0,0 +1,123 @@
+# -------------------------------------------------------------------------
+#   Copyright (C) 2020 Wipro Limited.
+#
+#   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.
+#
+# -------------------------------------------------------------------------
+#
+
+"""
+Module for processing response from conductor for slice selection
+"""
+
+from osdf.logging.osdf_logging import debug_log
+
+
+SLICE_PROFILE_FIELDS = ["latency", "max_number_of_ues", "coverage_area_ta_list",
+                        "ue_mobility_level", "resource_sharing_level", "exp_data_rate_ul",
+                        "exp_data_rate_dl", "area_traffic_cap_ul", "area_traffic_cap_dl",
+                        "activity_factor", "e2e_latency", "jitter", "survival_time",
+                        "exp_data_rate", "payload_size", "traffic_density", "conn_density",
+                        "reliability", "service_area_dimension", "cs_availability"]
+
+
+def conductor_response_processor(overall_recommendations, nst_info_map, request_info):
+    """Process conductor response to form the response for the API request
+        :param overall_recommendations: recommendations from conductor
+        :param nst_info_map: NST info from the request
+        :param request_info: request info
+        :return: response json as a dictionary
+    """
+    shared_nsi_solutions = list()
+    new_nsi_solutions = list()
+
+    for nst_name, recommendations in overall_recommendations.items():
+        for recommendation in recommendations:
+            nsi_set = set(values['candidate']['nsi_name'] for key, values in recommendation.items())
+            if len(nsi_set) == 1:
+                nsi = nsi_set.pop()
+                debug_log.debug("The NSSIs in the solution belongs to the same NSI {}".format(nsi))
+                shared_nsi_solution = dict()
+                shared_nsi_solution["NSIName"] = nsi
+                shared_nsi_solutions.append(shared_nsi_solution)
+            else:
+                nssi_solutions = get_nssi_solutions(recommendation)
+                new_nsi_solution = dict()
+                new_nsi_solution['matchLevel'] = ""
+                new_nsi_solution['NSTInfo'] = nst_info_map.get(nst_name)
+                new_nsi_solution['NSSISolutions'] = nssi_solutions
+                new_nsi_solutions.append(new_nsi_solution)
+
+    solutions = dict()
+    solutions['sharedNSISolutions'] = shared_nsi_solutions
+    solutions['newNSISolutions'] = new_nsi_solutions
+    return get_nsi_selection_response(request_info, solutions)
+
+
+def conductor_error_response_processor(request_info, error_message):
+    """Form response message from the error message
+        :param request_info: request info
+        :param error_message: error message while processing the request
+        :return: response json as dictionary
+    """
+    return {'requestId': request_info['requestId'],
+            'transactionId': request_info['transactionId'],
+            'requestStatus': 'error',
+            'statusMessage': error_message}
+
+
+def get_nssi_solutions(recommendation):
+    """Get nssi solutions from recommendation
+        :param recommendation: recommendation from conductor
+        :return: new nssi solutions list
+    """
+    nssi_solutions = list()
+
+    for nsst_name, nsst_rec in recommendation.items():
+        candidate = nsst_rec['candidate']
+        nssi_info, slice_profile = get_solution_from_candidate(candidate)
+        nsst_info = {"NSSTName": nsst_name}
+        nssi_solution = {"sliceProfile": slice_profile,
+                         "NSSTInfo": nsst_info,
+                         "NSSISolution": nssi_info}
+        nssi_solutions.append(nssi_solution)
+    return nssi_solutions
+
+
+def get_solution_from_candidate(candidate):
+    """Get nssi info from candidate
+        :param candidate: Candidate from the recommendation
+        :return: nssi_info and slice profile derived from candidate
+    """
+    slice_profile = dict()
+    nssi_info = {"NSSIName": candidate['instance_name'],
+                 "NSSIId": candidate['candidate_id']}
+
+    for field in SLICE_PROFILE_FIELDS:
+        if candidate[field]:
+            slice_profile[field] = candidate[field]
+
+    return nssi_info, slice_profile
+
+
+def get_nsi_selection_response(request_info, solutions):
+    """Get NSI selection response from final solution
+        :param request_info: request info
+        :param solutions: final solutions
+        :return: NSI selection response to send back as dictionary
+    """
+    return {'requestId': request_info['requestId'],
+            'transactionId': request_info['transactionId'],
+            'requestStatus': 'completed',
+            'statusMessage': '',
+            'solutions': solutions}