5.0.0 policy-handler - new PDP API or old PDP API4.0.0-ONAPdublin

- in R4 Dublin the policy-engine introduced a totally new API
- policy-handler now has a startup option to either use the new PDP API
  or the old PDP API that was created-updated before the end of 2018
- see README.md and README_pdp_api_v0.md for instructions on how to
  setup the policy-handler running either with the new PDP API
  or the old (pdp_api_v0) PDP API
- this is a massive refactoring that changed almost all the source files,
  but kept the old logic when using the old (pdp_api_v0) PDP API
- all the code related to PDP API version is split into two subfolders
  = pdp_api/ contains the new PDP API source code
  = pdp_api_v0/ contains the old (2018) PDP API source code
  = pdp_client.py imports from either pdp_api or pdp_api_v0
  = the rest of the code is only affected when it needs to branch
    the logic
- logging to policy_handler.log now shows the path of the source file to
  allow tracing which PDP API is actually used
- when the new PDP API is used, the policy-update flow is disabled
  = passive mode of operation
  = no web-socket
  = no periodic catch_up
  = no policy-filters
  = reduced web-API - only a single /policy_latest endpoint is available
    /policies_latest returns 404
    /catch_up request is accepted, but ignored
- on new PDP API: http /policy_latest returns the new data from the
  new PDP API with the following fields added by the policy-handler
  to keep other policy related parts intact in R4
  (see pdp_api/policy_utils.py)
  = "policyName" = policy_id + "." + "policyVersion" + ".xml"
  = "policyVersion" = str("metadata"."policy-version")
  = "config" - is the renamed "properties" from the new PDP API response
- unit tests are split into two subfolders as well
  = main/ for the new PDP API testing
  = pdp_api_v0/ for the old (2018) PDP API
- removed the following line from the license text of changed files
  ECOMP is a trademark and service mark of AT&T Intellectual Property.

- the new PDP API is expected to be extended and redesigned in R5 El Alto
- on retiring the old PDP API - the intention is to be able to remove
  the pdp_api_v0/ subfolder and minimal related cleanup of the code
  that imports that as well as the cleanup of the config.py, etc.

Change-Id: Ief9a2ae4541300308caaf97377f4ed051535dbe4
Signed-off-by: Alex Shatov <alexs@att.com>
Issue-ID: DCAEGEN2-1128

1 files changed, 123 insertions, 0 deletions

diff --git a/policyhandler/pdp_api/policy_utils.py b/policyhandler/pdp_api/policy_utils.py
new file mode 100644
index 0000000..1d06d14
--- /dev/null
+++ b/policyhandler/pdp_api/policy_utils.py
@@ -0,0 +1,123 @@
+# ================================================================================
+# Copyright (c) 2019 AT&T Intellectual Property. All rights reserved.
+# ================================================================================
+# 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.
+# ============LICENSE_END=========================================================
+#
+
+"""utils for policy usage and conversions"""
+
+from ..onap.audit import Audit
+from ..policy_consts import POLICY_BODY, POLICY_ID
+from .pdp_consts import (PDP_METADATA, PDP_POLICY_ID,
+                         PDP_POLICY_VERSION, PDP_PROPERTIES,
+                         PDP_REQ_ONAP_COMPONENT, PDP_REQ_ONAP_INSTANCE,
+                         PDP_REQ_ONAP_NAME, PDP_REQ_RESOURCE, POLICY_CONFIG,
+                         POLICY_NAME, POLICY_VERSION)
+
+
+class PolicyUtils(object):
+    """policy-client utils"""
+
+    @staticmethod
+    def gen_req_to_pdp(policy_id):
+        """request to get a single policy from pdp by policy_id"""
+        return {
+            PDP_REQ_ONAP_NAME: "DCAE",
+            PDP_REQ_ONAP_COMPONENT: Audit.service_name,
+            PDP_REQ_ONAP_INSTANCE: Audit.SERVICE_INSTANCE_UUID,
+            "action": "configure",
+            PDP_REQ_RESOURCE: {PDP_POLICY_ID: [policy_id]}
+        }
+
+    @staticmethod
+    def convert_to_policy(policy_body):
+        """
+        set policy id, name, version, config=properties and
+        wrap policy_body received from policy-engine with policy_id
+
+        input:
+        {
+            "type": "onap.policies.monitoring.cdap.tca.hi.lo.app",
+            "version": "1.0.0",
+            "metadata": {
+                "policy-id": "onap.scaleout.tca",
+                "policy-version": 1,
+                "description": "The scaleout policy for vDNS"
+            },
+            "properties": {
+                "tca_policy": {
+                    "domain": "measurementsForVfScaling",
+                    "metricsPerEventName": [
+                        {
+                            "eventName": "vLoadBalancer",
+                            "controlLoopSchemaType": "VNF",
+                            "policyScope": "type=configuration"
+                        }
+                    ]
+                }
+            }
+        }
+
+        output:
+        {
+            "policy_id": "onap.scaleout.tca",
+            "policy_body": {
+                "policyName": "onap.scaleout.tca.1.xml",
+                "policyVersion": 1,
+                "type": "onap.policies.monitoring.cdap.tca.hi.lo.app",
+                "version": "1.0.0",
+                "metadata": {
+                    "policy-id": "onap.scaleout.tca",
+                    "policy-version": 1,
+                    "description": "The scaleout policy for vDNS"
+                },
+                "config": {
+                    "tca_policy": {
+                        "domain": "measurementsForVfScaling",
+                        "metricsPerEventName": [
+                            {
+                                "eventName": "vLoadBalancer",
+                                "controlLoopSchemaType": "VNF",
+                                "policyScope": "type=configuration"
+                            }
+                        ]
+                    }
+                }
+            }
+        }
+        """
+        if not policy_body or not policy_body.get(PDP_PROPERTIES):
+            return None
+
+        pdp_metadata = policy_body.get(PDP_METADATA, {})
+        policy_id = pdp_metadata.get(PDP_POLICY_ID)
+        policy_version = pdp_metadata.get(PDP_POLICY_VERSION)
+        if not policy_id or not policy_version:
+            return None
+
+        policy_body[POLICY_NAME] = "{}.{}.xml".format(policy_id, policy_version)
+        policy_body[POLICY_VERSION] = str(policy_version)
+        policy_body[POLICY_CONFIG] = policy_body[PDP_PROPERTIES]
+        del policy_body[PDP_PROPERTIES]
+
+        return {POLICY_ID:policy_id, POLICY_BODY:policy_body}
+
+    @staticmethod
+    def validate_policy(policy):
+        """validate have non-empty config in policy"""
+        if not policy:
+            return False
+
+        policy_body = policy.get(POLICY_BODY)
+        return bool(policy_body and policy_body.get(POLICY_CONFIG))