Use singleton for api statistics
[policy/api.git] / main / src / main / java / org / onap / policy / api / main / rest / ApiRestController.java
index 79d8a64..eb60c5e 100644 (file)
@@ -3,8 +3,9 @@
  * ONAP Policy API\r
  * ================================================================================\r
  * Copyright (C) 2018 Samsung Electronics Co., Ltd. All rights reserved.\r
- * Copyright (C) 2019-2020 AT&T Intellectual Property. All rights reserved.\r
+ * Modifications Copyright (C) 2019-2021 AT&T Intellectual Property. All rights reserved.\r
  * Modifications Copyright (C) 2020 Nordix Foundation.\r
+ * Modifications Copyright (C) 2020 Bell Canada.\r
  * ================================================================================\r
  * Licensed under the Apache License, Version 2.0 (the "License");\r
  * you may not use this file except in compliance with the License.\r
@@ -37,6 +38,8 @@ import io.swagger.annotations.Info;
 import io.swagger.annotations.ResponseHeader;\r
 import io.swagger.annotations.SecurityDefinition;\r
 import io.swagger.annotations.SwaggerDefinition;\r
+import java.net.HttpURLConnection;\r
+import java.util.List;\r
 import java.util.UUID;\r
 import javax.ws.rs.Consumes;\r
 import javax.ws.rs.DELETE;\r
@@ -49,6 +52,7 @@ import javax.ws.rs.PathParam;
 import javax.ws.rs.Produces;\r
 import javax.ws.rs.QueryParam;\r
 import javax.ws.rs.core.Response;\r
+import javax.ws.rs.core.Response.Status;\r
 import org.onap.policy.api.main.rest.provider.HealthCheckProvider;\r
 import org.onap.policy.api.main.rest.provider.PolicyProvider;\r
 import org.onap.policy.api.main.rest.provider.PolicyTypeProvider;\r
@@ -90,6 +94,42 @@ public class ApiRestController extends CommonRestController {
 \r
     private static final Logger LOGGER = LoggerFactory.getLogger(ApiRestController.class);\r
 \r
+    private static final String ERROR_MESSAGE_NO_POLICIES_FOUND = "No policies found";\r
+\r
+    private static final String EXTENSION_NAME = "interface info";\r
+\r
+    private static final String API_VERSION_NAME = "api-version";\r
+    private static final String API_VERSION = "1.0.0";\r
+\r
+    private static final String LAST_MOD_NAME = "last-mod-release";\r
+\r
+    private static final String AUTHORIZATION_TYPE = "basicAuth";\r
+\r
+    private static final String VERSION_MINOR_NAME = "X-MinorVersion";\r
+    private static final String VERSION_MINOR_DESCRIPTION =\r
+        "Used to request or communicate a MINOR version back from the client"\r
+            + " to the server, and from the server back to the client";\r
+\r
+    private static final String VERSION_PATCH_NAME = "X-PatchVersion";\r
+    private static final String VERSION_PATCH_DESCRIPTION = "Used only to communicate a PATCH version in a response for"\r
+        + " troubleshooting purposes only, and will not be provided by" + " the client on request";\r
+\r
+    private static final String VERSION_LATEST_NAME = "X-LatestVersion";\r
+    private static final String VERSION_LATEST_DESCRIPTION = "Used only to communicate an API's latest version";\r
+\r
+    private static final String REQUEST_ID_NAME = "X-ONAP-RequestID";\r
+    private static final String REQUEST_ID_HDR_DESCRIPTION = "Used to track REST transactions for logging purpose";\r
+    private static final String REQUEST_ID_PARAM_DESCRIPTION = "RequestID for http transaction";\r
+\r
+    private static final String AUTHENTICATION_ERROR_MESSAGE = "Authentication Error";\r
+    private static final String AUTHORIZATION_ERROR_MESSAGE = "Authorization Error";\r
+    private static final String SERVER_ERROR_MESSAGE = "Internal Server Error";\r
+    private static final String NOT_FOUND_MESSAGE = "Resource Not Found";\r
+    private static final String INVALID_BODY_MESSAGE = "Invalid Body";\r
+    private static final String INVALID_PAYLOAD_MESSAGE = "Not Acceptable Payload";\r
+    private static final String HTTP_CONFLICT_MESSAGE = "Delete Conflict, Rule Violation";\r
+\r
+\r
     /**\r
      * Retrieves the healthcheck status of the API component.\r
      *\r
@@ -100,27 +140,27 @@ public class ApiRestController extends CommonRestController {
     @ApiOperation(value = "Perform a system healthcheck", notes = "Returns healthy status of the Policy API component",\r
         response = HealthCheckReport.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"HealthCheck", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"HealthCheck", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response\r
-        getHealthCheck(@HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        getHealthCheck(@HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
         updateApiStatisticsCounter(Target.OTHER, Result.SUCCESS, HttpMethod.GET);\r
         return makeOkResponse(requestId, new HealthCheckProvider().performHealthCheck());\r
@@ -137,27 +177,27 @@ public class ApiRestController extends CommonRestController {
         notes = "Returns current statistics including the counters of API invocation",\r
         response = StatisticsReport.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"Statistics", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Statistics", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response\r
-        getStatistics(@HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        getStatistics(@HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
         updateApiStatisticsCounter(Target.OTHER, Result.SUCCESS, HttpMethod.GET);\r
 \r
@@ -175,34 +215,34 @@ public class ApiRestController extends CommonRestController {
         notes = "Returns a list of existing policy types stored in Policy Framework",\r
         response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"PolicyType", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"PolicyType", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response\r
-        getAllPolicyTypes(@HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        getAllPolicyTypes(@HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
-        try (PolicyTypeProvider policyTypeProvider = new PolicyTypeProvider()) {\r
+        try (var policyTypeProvider = new PolicyTypeProvider()) {\r
             ToscaServiceTemplate serviceTemplate = policyTypeProvider.fetchPolicyTypes(null, null);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.SUCCESS, HttpMethod.GET);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("GET /policytypes", pfme);\r
+            LOGGER.warn("GET /policytypes", pfme);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.FAILURE, HttpMethod.GET);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
@@ -221,36 +261,36 @@ public class ApiRestController extends CommonRestController {
         notes = "Returns a list of all available versions for the specified policy type",\r
         response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"PolicyType", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"PolicyType", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response getAllVersionsOfPolicyType(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
-        try (PolicyTypeProvider policyTypeProvider = new PolicyTypeProvider()) {\r
+        try (var policyTypeProvider = new PolicyTypeProvider()) {\r
             ToscaServiceTemplate serviceTemplate = policyTypeProvider.fetchPolicyTypes(policyTypeId, null);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.SUCCESS, HttpMethod.GET);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("GET /policytypes/{}", policyTypeId, pfme);\r
+            LOGGER.warn("GET /policytypes/{}", policyTypeId, pfme);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.FAILURE, HttpMethod.GET);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
@@ -269,37 +309,37 @@ public class ApiRestController extends CommonRestController {
     @ApiOperation(value = "Retrieve one particular version of a policy type",\r
         notes = "Returns a particular version for the specified policy type", response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"PolicyType", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"PolicyType", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response getSpecificVersionOfPolicyType(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
         @PathParam("versionId") @ApiParam(value = "Version of policy type", required = true) String versionId,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
-        try (PolicyTypeProvider policyTypeProvider = new PolicyTypeProvider()) {\r
+        try (var policyTypeProvider = new PolicyTypeProvider()) {\r
             ToscaServiceTemplate serviceTemplate = policyTypeProvider.fetchPolicyTypes(policyTypeId, versionId);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.SUCCESS, HttpMethod.GET);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("GET /policytypes/{}/versions/{}", policyTypeId, versionId, pfme);\r
+            LOGGER.warn("GET /policytypes/{}/versions/{}", policyTypeId, versionId, pfme);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.FAILURE, HttpMethod.GET);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
@@ -317,36 +357,36 @@ public class ApiRestController extends CommonRestController {
     @ApiOperation(value = "Retrieve latest version of a policy type",\r
         notes = "Returns latest version for the specified policy type", response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"PolicyType", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"PolicyType", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response getLatestVersionOfPolicyType(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
-        try (PolicyTypeProvider policyTypeProvider = new PolicyTypeProvider()) {\r
+        try (var policyTypeProvider = new PolicyTypeProvider()) {\r
             ToscaServiceTemplate serviceTemplate = policyTypeProvider.fetchLatestPolicyTypes(policyTypeId);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.SUCCESS, HttpMethod.GET);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("GET /policytypes/{}/versions/latest", policyTypeId, pfme);\r
+            LOGGER.warn("GET /policytypes/{}/versions/latest", policyTypeId, pfme);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.FAILURE, HttpMethod.GET);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
@@ -362,43 +402,43 @@ public class ApiRestController extends CommonRestController {
     @POST\r
     @Path("/policytypes")\r
     @ApiOperation(value = "Create a new policy type", notes = "Client should provide TOSCA body of the new policy type",\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"PolicyType", },\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"PolicyType", },\r
         response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 400, message = "Invalid Body"),\r
-        @ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 406, message = "Not Acceptable Payload"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_BAD_REQUEST, message = INVALID_BODY_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_ACCEPTABLE, message = INVALID_PAYLOAD_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response createPolicyType(\r
         @ApiParam(value = "Entity body of policy type", required = true) ToscaServiceTemplate body,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
         if (NetLoggerUtil.getNetworkLogger().isInfoEnabled()) {\r
             NetLoggerUtil.log(EventType.IN, CommInfrastructure.REST, "/policytypes", toJson(body));\r
         }\r
 \r
-        try (PolicyTypeProvider policyTypeProvider = new PolicyTypeProvider()) {\r
+        try (var policyTypeProvider = new PolicyTypeProvider()) {\r
             ToscaServiceTemplate serviceTemplate = policyTypeProvider.createPolicyType(body);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.SUCCESS, HttpMethod.POST);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("POST /policytypes", pfme);\r
+            LOGGER.warn("POST /policytypes", pfme);\r
             updateApiStatisticsCounter(Target.POLICY_TYPE, Result.FAILURE, HttpMethod.POST);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
@@ -418,39 +458,41 @@ public class ApiRestController extends CommonRestController {
         notes = "Rule 1: pre-defined policy types cannot be deleted;"\r
             + "Rule 2: policy types that are in use (parameterized by a TOSCA policy) cannot be deleted."\r
             + "The parameterizing TOSCA policies must be deleted first;",\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"PolicyType", },\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"PolicyType", },\r
         response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 409, message = "Delete Conflict, Rule Violation"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_CONFLICT, message = HTTP_CONFLICT_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response deleteSpecificVersionOfPolicyType(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
         @PathParam("versionId") @ApiParam(value = "Version of policy type", required = true) String versionId,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
-        try (PolicyTypeProvider policyTypeProvider = new PolicyTypeProvider()) {\r
+        try (var policyTypeProvider = new PolicyTypeProvider()) {\r
             ToscaServiceTemplate serviceTemplate = policyTypeProvider.deletePolicyType(policyTypeId, versionId);\r
+            updateApiStatisticsCounter(Target.POLICY_TYPE, Result.SUCCESS, HttpMethod.DELETE);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("DELETE /policytypes/{}/versions/{}", policyTypeId, versionId, pfme);\r
+            LOGGER.warn("DELETE /policytypes/{}/versions/{}", policyTypeId, versionId, pfme);\r
+            updateApiStatisticsCounter(Target.POLICY_TYPE, Result.FAILURE, HttpMethod.DELETE);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
     }\r
@@ -463,7 +505,6 @@ public class ApiRestController extends CommonRestController {
      *\r
      * @return the Response object containing the results of the API operation\r
      */\r
-    // @formatter:off\r
     @GET\r
     @Path("/policytypes/{policyTypeId}/versions/{policyTypeVersion}/policies")\r
     @ApiOperation(\r
@@ -471,53 +512,50 @@ public class ApiRestController extends CommonRestController {
         notes = "Returns a list of all versions of specified policy created for the specified policy type version",\r
         response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"Policy,"},\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy,"},\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {\r
-                @ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")\r
             })\r
         }\r
     )\r
     @ApiResponses(value = {\r
-        @ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)\r
     })\r
     public Response getAllPolicies(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
         @PathParam("policyTypeVersion") @ApiParam(value = "Version of policy type",\r
             required = true) String policyTypeVersion,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId,\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId,\r
         @QueryParam("mode") @DefaultValue("bare") @ApiParam("Fetch mode for policies, BARE for bare policies (default),"\r
             + " REFERENCED for fully referenced policies") PolicyFetchMode mode\r
     ) {\r
 \r
-        try (PolicyProvider policyProvider = new PolicyProvider()) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
             ToscaServiceTemplate serviceTemplate =\r
                 policyProvider.fetchPolicies(policyTypeId, policyTypeVersion, null, null, mode);\r
             updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.GET);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("GET /policytypes/{}/versions/{}/policies", policyTypeId, policyTypeVersion, pfme);\r
+            LOGGER.warn("GET /policytypes/{}/versions/{}/policies", policyTypeId, policyTypeVersion, pfme);\r
             updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.GET);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
     }\r
-    // @formatter:on\r
 \r
     /**\r
      * Retrieves all versions of a particular policy.\r
@@ -528,59 +566,55 @@ public class ApiRestController extends CommonRestController {
      *\r
      * @return the Response object containing the results of the API operation\r
      */\r
-    // @formatter:off\r
     @GET\r
     @Path("/policytypes/{policyTypeId}/versions/{policyTypeVersion}/policies/{policyId}")\r
     @ApiOperation(value = "Retrieve all version details of a policy created for a particular policy type version",\r
         notes = "Returns a list of all version details of the specified policy", response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"Policy", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {\r
-                @ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")\r
             })\r
         }\r
     )\r
     @ApiResponses(value = {\r
-        @ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)\r
     })\r
     public Response getAllVersionsOfPolicy(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
         @PathParam("policyTypeVersion") @ApiParam(value = "Version of policy type",\r
             required = true) String policyTypeVersion,\r
         @PathParam("policyId") @ApiParam(value = "ID of policy", required = true) String policyId,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId,\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId,\r
         @QueryParam("mode") @DefaultValue("bare") @ApiParam("Fetch mode for policies, BARE for bare policies (default),"\r
             + " REFERENCED for fully referenced policies") PolicyFetchMode mode\r
     ) {\r
-        try (PolicyProvider policyProvider = new PolicyProvider()) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
             ToscaServiceTemplate serviceTemplate =\r
                 policyProvider.fetchPolicies(policyTypeId, policyTypeVersion, policyId, null, mode);\r
             updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.GET);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("/policytypes/{}/versions/{}/policies/{}", policyTypeId, policyTypeVersion, policyId, pfme);\r
+            LOGGER.warn("/policytypes/{}/versions/{}/policies/{}", policyTypeId, policyTypeVersion, policyId, pfme);\r
             updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.GET);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
     }\r
-    // @formatter:on\r
 \r
     /**\r
      * Retrieves the specified version of a particular policy.\r
@@ -592,38 +626,35 @@ public class ApiRestController extends CommonRestController {
      *\r
      * @return the Response object containing the results of the API operation\r
      */\r
-    // @formatter:off\r
     @GET\r
     @Path("/policytypes/{policyTypeId}/versions/{policyTypeVersion}/policies/{policyId}/versions/{policyVersion}")\r
     @ApiOperation(value = "Retrieve one version of a policy created for a particular policy type version",\r
         notes = "Returns a particular version of specified policy created for the specified policy type version",\r
         response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"Policy", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {\r
-                @ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")\r
             })\r
         }\r
     )\r
     @ApiResponses(value = {\r
-        @ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)\r
     })\r
     public Response getSpecificVersionOfPolicy(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
@@ -631,23 +662,22 @@ public class ApiRestController extends CommonRestController {
             required = true) String policyTypeVersion,\r
         @PathParam("policyId") @ApiParam(value = "ID of policy", required = true) String policyId,\r
         @PathParam("policyVersion") @ApiParam(value = "Version of policy", required = true) String policyVersion,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId,\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId,\r
         @QueryParam("mode") @DefaultValue("bare") @ApiParam("Fetch mode for policies, BARE for bare policies (default),"\r
             + " REFERENCED for fully referenced policies") PolicyFetchMode mode\r
     ) {\r
-        try (PolicyProvider policyProvider = new PolicyProvider()) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
             ToscaServiceTemplate serviceTemplate =\r
                 policyProvider.fetchPolicies(policyTypeId, policyTypeVersion, policyId, policyVersion, mode);\r
             updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.GET);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("GET /policytypes/{}/versions/{}/policies/{}/versions/{}", policyTypeId, policyTypeVersion,\r
+            LOGGER.warn("GET /policytypes/{}/versions/{}/policies/{}/versions/{}", policyTypeId, policyTypeVersion,\r
                 policyId, policyVersion, pfme);\r
             updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.GET);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
     }\r
-    // @formatter:on\r
 \r
     /**\r
      * Retrieves the latest version of a particular policy.\r
@@ -663,42 +693,42 @@ public class ApiRestController extends CommonRestController {
     @ApiOperation(value = "Retrieve the latest version of a particular policy",\r
         notes = "Returns the latest version of specified policy", response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"Policy", },\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response getLatestVersionOfPolicy(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
         @PathParam("policyTypeVersion") @ApiParam(value = "Version of policy type",\r
             required = true) String policyTypeVersion,\r
         @PathParam("policyId") @ApiParam(value = "ID of policy", required = true) String policyId,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId,\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId,\r
         @QueryParam("mode") @ApiParam("Fetch mode for policies, TERSE for bare policies (default), "\r
             + "REFERENCED for fully referenced policies") PolicyFetchMode mode) {\r
 \r
-        try (PolicyProvider policyProvider = new PolicyProvider()) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
             ToscaServiceTemplate serviceTemplate =\r
                 policyProvider.fetchLatestPolicies(policyTypeId, policyTypeVersion, policyId, mode);\r
             updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.GET);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("GET /policytypes/{}/versions/{}/policies/{}/versions/latest", policyTypeId, policyTypeVersion,\r
+            LOGGER.warn("GET /policytypes/{}/versions/{}/policies/{}/versions/latest", policyTypeId, policyTypeVersion,\r
                 policyId, pfme);\r
             updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.GET);\r
             return makeErrorResponse(requestId, pfme);\r
@@ -718,35 +748,35 @@ public class ApiRestController extends CommonRestController {
     @Path("/policytypes/{policyTypeId}/versions/{policyTypeVersion}/policies")\r
     @ApiOperation(value = "Create a new policy for a policy type version",\r
         notes = "Client should provide TOSCA body of the new policy",\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"Policy", },\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
             response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 400, message = "Invalid Body"),\r
-        @ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 406, message = "Not Acceptable Payload"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_BAD_REQUEST, message = INVALID_BODY_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_ACCEPTABLE, message = INVALID_PAYLOAD_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response createPolicy(\r
         @PathParam("policyTypeId") @ApiParam(value = "ID of policy type", required = true) String policyTypeId,\r
         @PathParam("policyTypeVersion") @ApiParam(value = "Version of policy type",\r
             required = true) String policyTypeVersion,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId,\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId,\r
         @ApiParam(value = "Entity body of policy", required = true) ToscaServiceTemplate body) {\r
 \r
         if (NetLoggerUtil.getNetworkLogger().isInfoEnabled()) {\r
@@ -754,17 +784,188 @@ public class ApiRestController extends CommonRestController {
                 "/policytypes/" + policyTypeId + "/versions/" + policyTypeVersion + "/policies", toJson(body));\r
         }\r
 \r
-        try (PolicyProvider policyProvider = new PolicyProvider()) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
             ToscaServiceTemplate serviceTemplate = policyProvider.createPolicy(policyTypeId, policyTypeVersion, body);\r
             updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.POST);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("POST /policytypes/{}/versions/{}/policies", policyTypeId, policyTypeVersion, pfme);\r
+            LOGGER.warn("POST /policytypes/{}/versions/{}/policies", policyTypeId, policyTypeVersion, pfme);\r
             updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.POST);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
     }\r
 \r
+    /**\r
+     * Deletes the specified version of a particular policy.\r
+     *\r
+     * @param policyTypeId the ID of specified policy type\r
+     * @param policyTypeVersion the version of specified policy type\r
+     * @param policyId the ID of specified policy\r
+     * @param policyVersion the version of specified policy\r
+     *\r
+     * @return the Response object containing the results of the API operation\r
+     */\r
+    @DELETE\r
+    @Path("/policytypes/{policyTypeId}/versions/{policyTypeVersion}/policies/{policyId}/versions/{policyVersion}")\r
+    @ApiOperation(value = "Delete a particular version of a policy",\r
+        notes = "Rule: the version that has been deployed in PDP group(s) cannot be deleted",\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
+        response = ToscaServiceTemplate.class,\r
+        responseHeaders = {\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        extensions = {\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Dublin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_CONFLICT, message = HTTP_CONFLICT_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
+    public Response deleteSpecificVersionOfPolicy(\r
+        @PathParam("policyTypeId") @ApiParam(value = "PolicyType ID", required = true) String policyTypeId,\r
+        @PathParam("policyTypeVersion") @ApiParam(value = "Version of policy type",\r
+            required = true) String policyTypeVersion,\r
+        @PathParam("policyId") @ApiParam(value = "ID of policy", required = true) String policyId,\r
+        @PathParam("policyVersion") @ApiParam(value = "Version of policy", required = true) String policyVersion,\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
+\r
+        try (var policyProvider = new PolicyProvider()) {\r
+            ToscaServiceTemplate serviceTemplate =\r
+                policyProvider.deletePolicy(policyTypeId, policyTypeVersion, policyId, policyVersion);\r
+            updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.DELETE);\r
+            return makeOkResponse(requestId, serviceTemplate);\r
+        } catch (PfModelException | PfModelRuntimeException pfme) {\r
+            LOGGER.warn("DELETE /policytypes/{}/versions/{}/policies/{}/versions/{}", policyTypeId, policyTypeVersion,\r
+                policyId, policyVersion, pfme);\r
+            updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.DELETE);\r
+            return makeErrorResponse(requestId, pfme);\r
+        }\r
+    }\r
+\r
+    /**\r
+     * Retrieves all the available policies.\r
+     *\r
+     * @return the Response object containing the results of the API operation\r
+     */\r
+    @GET\r
+    @Path("/policies")\r
+    @ApiOperation(value = "Retrieve all versions of available policies",\r
+        notes = "Returns all version of available policies",\r
+        response = ToscaServiceTemplate.class,\r
+        responseHeaders = {\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
+        extensions = {\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Guilin")\r
+            })\r
+        }\r
+    )\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)\r
+    })\r
+    public Response getPolicies(\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId,\r
+        @QueryParam("mode") @DefaultValue("bare") @ApiParam("Fetch mode for policies, BARE for bare policies (default),"\r
+            + " REFERENCED for fully referenced policies") PolicyFetchMode mode\r
+    ) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
+            ToscaServiceTemplate serviceTemplate =\r
+                policyProvider.fetchPolicies(null, null, null, null, mode);\r
+            updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.GET);\r
+            return makeOkResponse(requestId, serviceTemplate);\r
+        } catch (PfModelException | PfModelRuntimeException pfme) {\r
+            LOGGER.warn("GET /policies/ --", pfme);\r
+            updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.GET);\r
+            if (pfme.getErrorResponse().getResponseCode().equals(Status.NOT_FOUND)) {\r
+                pfme.getErrorResponse().setErrorMessage(ERROR_MESSAGE_NO_POLICIES_FOUND);\r
+                pfme.getErrorResponse().setErrorDetails(List.of(ERROR_MESSAGE_NO_POLICIES_FOUND));\r
+            }\r
+            return makeErrorResponse(requestId, pfme);\r
+        }\r
+    }\r
+\r
+    /**\r
+     * Retrieves the specified version of a particular policy.\r
+     *\r
+     * @param policyId the Name of specified policy\r
+     * @param policyVersion the version of specified policy\r
+     *\r
+     * @return the Response object containing the results of the API operation\r
+     */\r
+    @GET\r
+    @Path("/policies/{policyId}/versions/{policyVersion}")\r
+    @ApiOperation(value = "Retrieve specific version of a specified policy",\r
+        notes = "Returns a particular version of specified policy",\r
+        response = ToscaServiceTemplate.class,\r
+        responseHeaders = {\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
+                response = String.class),\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
+        extensions = {\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Guilin")\r
+            })\r
+        }\r
+    )\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)\r
+    })\r
+    public Response getSpecificPolicy(\r
+        @PathParam("policyId") @ApiParam(value = "Name of policy", required = true) String policyId,\r
+        @PathParam("policyVersion") @ApiParam(value = "Version of policy", required = true) String policyVersion,\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId,\r
+        @QueryParam("mode") @DefaultValue("bare") @ApiParam("Fetch mode for policies, BARE for bare policies (default),"\r
+            + " REFERENCED for fully referenced policies") PolicyFetchMode mode\r
+    ) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
+            ToscaServiceTemplate serviceTemplate =\r
+                policyProvider.fetchPolicies(null, null, policyId, policyVersion, mode);\r
+            updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.GET);\r
+            return makeOkResponse(requestId, serviceTemplate);\r
+        } catch (PfModelException | PfModelRuntimeException pfme) {\r
+            LOGGER.warn("GET /policies/{}/versions/{}", policyId, policyVersion, pfme);\r
+            updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.GET);\r
+            return makeErrorResponse(requestId, pfme);\r
+        }\r
+    }\r
+\r
     /**\r
      * Creates one or more new policies in one call.\r
      *\r
@@ -776,44 +977,44 @@ public class ApiRestController extends CommonRestController {
     @Path("/policies")\r
     @ApiOperation(value = "Create one or more new policies",\r
         notes = "Client should provide TOSCA body of the new polic(ies)",\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"Policy", },\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
             response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "El Alto")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 400, message = "Invalid Body"),\r
-        @ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 406, message = "Not Acceptable Payload"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "El Alto")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_BAD_REQUEST, message = INVALID_BODY_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_ACCEPTABLE, message = INVALID_PAYLOAD_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
     public Response createPolicies(\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId,\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId,\r
         @ApiParam(value = "Entity body of policy", required = true) ToscaServiceTemplate body) {\r
 \r
         if (NetLoggerUtil.getNetworkLogger().isInfoEnabled()) {\r
             NetLoggerUtil.log(EventType.IN, CommInfrastructure.REST, "/policies", toJson(body));\r
         }\r
 \r
-        try (PolicyProvider policyProvider = new PolicyProvider()) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
             ToscaServiceTemplate serviceTemplate = policyProvider.createPolicies(body);\r
             updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.POST);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("POST /policies", pfme);\r
+            LOGGER.warn("POST /policies", pfme);\r
             updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.POST);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
@@ -822,59 +1023,57 @@ public class ApiRestController extends CommonRestController {
     /**\r
      * Deletes the specified version of a particular policy.\r
      *\r
-     * @param policyTypeId the ID of specified policy type\r
-     * @param policyTypeVersion the version of specified policy type\r
      * @param policyId the ID of specified policy\r
      * @param policyVersion the version of specified policy\r
      *\r
      * @return the Response object containing the results of the API operation\r
      */\r
     @DELETE\r
-    @Path("/policytypes/{policyTypeId}/versions/{policyTypeVersion}/policies/{policyId}/versions/{policyVersion}")\r
+    @Path("/policies/{policyId}/versions/{policyVersion}")\r
     @ApiOperation(value = "Delete a particular version of a policy",\r
         notes = "Rule: the version that has been deployed in PDP group(s) cannot be deleted",\r
-        authorizations = @Authorization(value = "basicAuth"), tags = {"Policy", },\r
-            response = ToscaServiceTemplate.class,\r
+        authorizations = @Authorization(value = AUTHORIZATION_TYPE), tags = {"Policy", },\r
+        response = ToscaServiceTemplate.class,\r
         responseHeaders = {\r
-            @ResponseHeader(name = "X-MinorVersion",\r
-                description = "Used to request or communicate a MINOR version back from the client"\r
-                    + " to the server, and from the server back to the client",\r
+            @ResponseHeader(name = VERSION_MINOR_NAME,\r
+                description = VERSION_MINOR_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-PatchVersion",\r
-                description = "Used only to communicate a PATCH version in a response for"\r
-                    + " troubleshooting purposes only, and will not be provided by" + " the client on request",\r
+            @ResponseHeader(name = VERSION_PATCH_NAME,\r
+                description = VERSION_PATCH_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-LatestVersion", description = "Used only to communicate an API's latest version",\r
+            @ResponseHeader(name = VERSION_LATEST_NAME, description = VERSION_LATEST_DESCRIPTION,\r
                 response = String.class),\r
-            @ResponseHeader(name = "X-ONAP-RequestID",\r
-                description = "Used to track REST transactions for logging purpose", response = UUID.class)},\r
+            @ResponseHeader(name = REQUEST_ID_NAME,\r
+                description = REQUEST_ID_HDR_DESCRIPTION, response = UUID.class)},\r
         extensions = {\r
-            @Extension(name = "interface info", properties = {@ExtensionProperty(name = "api-version", value = "1.0.0"),\r
-                @ExtensionProperty(name = "last-mod-release", value = "Dublin")})})\r
-    @ApiResponses(value = {@ApiResponse(code = 401, message = "Authentication Error"),\r
-        @ApiResponse(code = 403, message = "Authorization Error"),\r
-        @ApiResponse(code = 404, message = "Resource Not Found"),\r
-        @ApiResponse(code = 409, message = "Delete Conflict, Rule Violation"),\r
-        @ApiResponse(code = 500, message = "Internal Server Error")})\r
-    public Response deleteSpecificVersionOfPolicy(\r
-        @PathParam("policyTypeId") @ApiParam(value = "PolicyType ID", required = true) String policyTypeId,\r
-        @PathParam("policyTypeVersion") @ApiParam(value = "Version of policy type",\r
-            required = true) String policyTypeVersion,\r
+            @Extension(name = EXTENSION_NAME, properties = {\r
+                @ExtensionProperty(name = API_VERSION_NAME, value = API_VERSION),\r
+                @ExtensionProperty(name = LAST_MOD_NAME, value = "Guilin")})})\r
+    @ApiResponses(value = {\r
+        @ApiResponse(code = HttpURLConnection.HTTP_UNAUTHORIZED, message = AUTHENTICATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_FORBIDDEN, message = AUTHORIZATION_ERROR_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_NOT_FOUND, message = NOT_FOUND_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_CONFLICT, message = HTTP_CONFLICT_MESSAGE),\r
+        @ApiResponse(code = HttpURLConnection.HTTP_INTERNAL_ERROR, message = SERVER_ERROR_MESSAGE)})\r
+    public Response deleteSpecificPolicy(\r
         @PathParam("policyId") @ApiParam(value = "ID of policy", required = true) String policyId,\r
         @PathParam("policyVersion") @ApiParam(value = "Version of policy", required = true) String policyVersion,\r
-        @HeaderParam("X-ONAP-RequestID") @ApiParam("RequestID for http transaction") UUID requestId) {\r
+        @HeaderParam(REQUEST_ID_NAME) @ApiParam(REQUEST_ID_PARAM_DESCRIPTION) UUID requestId) {\r
 \r
-        try (PolicyProvider policyProvider = new PolicyProvider()) {\r
+        try (var policyProvider = new PolicyProvider()) {\r
             ToscaServiceTemplate serviceTemplate =\r
-                policyProvider.deletePolicy(policyTypeId, policyTypeVersion, policyId, policyVersion);\r
+                policyProvider.deletePolicy(null, null, policyId, policyVersion);\r
+            updateApiStatisticsCounter(Target.POLICY, Result.SUCCESS, HttpMethod.DELETE);\r
             return makeOkResponse(requestId, serviceTemplate);\r
         } catch (PfModelException | PfModelRuntimeException pfme) {\r
-            LOGGER.debug("DELETE /policytypes/{}/versions/{}/policies/{}/versions/{}", policyTypeId, policyTypeVersion,\r
-                policyId, policyVersion, pfme);\r
+            LOGGER.warn("DELETE /policies/{}/versions/{}", policyId, policyVersion, pfme);\r
+            updateApiStatisticsCounter(Target.POLICY, Result.FAILURE, HttpMethod.DELETE);\r
             return makeErrorResponse(requestId, pfme);\r
         }\r
     }\r
 \r
+\r
+\r
     private enum Target {\r
         POLICY,\r
         POLICY_TYPE,\r
@@ -888,12 +1087,14 @@ public class ApiRestController extends CommonRestController {
 \r
     private enum HttpMethod {\r
         POST,\r
-        GET\r
+        GET,\r
+        DELETE\r
     }\r
 \r
     private void updateApiStatisticsCounter(Target target, Result result, HttpMethod http) {\r
 \r
-        ApiStatisticsManager.updateTotalApiCallCount();\r
+        var mgr = ApiStatisticsManager.getInstance();\r
+        mgr.updateTotalApiCallCount();\r
 \r
         switch (target) {\r
             case POLICY:\r
@@ -903,56 +1104,104 @@ public class ApiRestController extends CommonRestController {
                 updatePolicyTypeStats(result, http);\r
                 break;\r
             default:\r
-                ApiStatisticsManager.updateApiCallSuccessCount();\r
+                mgr.updateApiCallSuccessCount();\r
                 break;\r
         }\r
     }\r
 \r
     private void updatePolicyStats(Result result, HttpMethod http) {\r
+        var mgr = ApiStatisticsManager.getInstance();\r
+\r
         if (result == Result.SUCCESS) {\r
-            if (http == HttpMethod.GET) {\r
-                ApiStatisticsManager.updateApiCallSuccessCount();\r
-                ApiStatisticsManager.updateTotalPolicyGetCount();\r
-                ApiStatisticsManager.updatePolicyGetSuccessCount();\r
-            } else if (http == HttpMethod.POST) {\r
-                ApiStatisticsManager.updateApiCallSuccessCount();\r
-                ApiStatisticsManager.updateTotalPolicyPostCount();\r
-                ApiStatisticsManager.updatePolicyPostSuccessCount();\r
+            switch (http) {\r
+                case GET:\r
+                    mgr.updateApiCallSuccessCount();\r
+                    mgr.updateTotalPolicyGetCount();\r
+                    mgr.updatePolicyGetSuccessCount();\r
+                    break;\r
+                case POST:\r
+                    mgr.updateApiCallSuccessCount();\r
+                    mgr.updateTotalPolicyPostCount();\r
+                    mgr.updatePolicyPostSuccessCount();\r
+                    break;\r
+                case DELETE:\r
+                    mgr.updateApiCallSuccessCount();\r
+                    mgr.updateTotalPolicyDeleteCount();\r
+                    mgr.updatePolicyDeleteSuccessCount();\r
+                    break;\r
+                default:\r
+                    mgr.updateApiCallSuccessCount();\r
+                    break;\r
             }\r
         } else {\r
-            if (http == HttpMethod.GET) {\r
-                ApiStatisticsManager.updateApiCallFailureCount();\r
-                ApiStatisticsManager.updateTotalPolicyGetCount();\r
-                ApiStatisticsManager.updatePolicyGetFailureCount();\r
-            } else {\r
-                ApiStatisticsManager.updateApiCallFailureCount();\r
-                ApiStatisticsManager.updateTotalPolicyPostCount();\r
-                ApiStatisticsManager.updatePolicyPostFailureCount();\r
+            switch (http) {\r
+                case GET:\r
+                    mgr.updateApiCallFailureCount();\r
+                    mgr.updateTotalPolicyGetCount();\r
+                    mgr.updatePolicyGetFailureCount();\r
+                    break;\r
+                case POST:\r
+                    mgr.updateApiCallFailureCount();\r
+                    mgr.updateTotalPolicyPostCount();\r
+                    mgr.updatePolicyPostFailureCount();\r
+                    break;\r
+                case DELETE:\r
+                    mgr.updateApiCallFailureCount();\r
+                    mgr.updateTotalPolicyDeleteCount();\r
+                    mgr.updatePolicyDeleteFailureCount();\r
+                    break;\r
+                default:\r
+                    mgr.updateApiCallFailureCount();\r
+                    break;\r
             }\r
         }\r
     }\r
 \r
     private void updatePolicyTypeStats(Result result, HttpMethod http) {\r
+        var mgr = ApiStatisticsManager.getInstance();\r
+\r
         if (result == Result.SUCCESS) {\r
-            if (http == HttpMethod.GET) {\r
-                ApiStatisticsManager.updateApiCallSuccessCount();\r
-                ApiStatisticsManager.updateTotalPolicyTypeGetCount();\r
-                ApiStatisticsManager.updatePolicyTypeGetSuccessCount();\r
-            } else if (http == HttpMethod.POST) {\r
-                ApiStatisticsManager.updateApiCallSuccessCount();\r
-                ApiStatisticsManager.updatePolicyTypePostSuccessCount();\r
-                ApiStatisticsManager.updatePolicyTypePostSuccessCount();\r
+            switch (http) {\r
+                case GET:\r
+                    mgr.updateApiCallSuccessCount();\r
+                    mgr.updateTotalPolicyTypeGetCount();\r
+                    mgr.updatePolicyTypeGetSuccessCount();\r
+                    break;\r
+                case POST:\r
+                    mgr.updateApiCallSuccessCount();\r
+                    mgr.updateTotalPolicyTypePostCount();\r
+                    mgr.updatePolicyTypePostSuccessCount();\r
+                    break;\r
+                case DELETE:\r
+                    mgr.updateApiCallSuccessCount();\r
+                    mgr.updateTotalPolicyTypeDeleteCount();\r
+                    mgr.updatePolicyTypeDeleteSuccessCount();\r
+                    break;\r
+                default:\r
+                    mgr.updateApiCallSuccessCount();\r
+                    break;\r
             }\r
         } else {\r
-            if (http == HttpMethod.GET) {\r
-                ApiStatisticsManager.updateApiCallFailureCount();\r
-                ApiStatisticsManager.updateTotalPolicyTypeGetCount();\r
-                ApiStatisticsManager.updatePolicyTypeGetFailureCount();\r
-            } else {\r
-                ApiStatisticsManager.updateApiCallFailureCount();\r
-                ApiStatisticsManager.updateTotalPolicyTypePostCount();\r
-                ApiStatisticsManager.updatePolicyTypePostFailureCount();\r
+            switch (http) {\r
+                case GET:\r
+                    mgr.updateApiCallFailureCount();\r
+                    mgr.updateTotalPolicyTypeGetCount();\r
+                    mgr.updatePolicyTypeGetFailureCount();\r
+                    break;\r
+                case POST:\r
+                    mgr.updateApiCallFailureCount();\r
+                    mgr.updateTotalPolicyTypePostCount();\r
+                    mgr.updatePolicyTypePostFailureCount();\r
+                    break;\r
+                case DELETE:\r
+                    mgr.updateApiCallFailureCount();\r
+                    mgr.updateTotalPolicyTypeDeleteCount();\r
+                    mgr.updatePolicyTypeDeleteFailureCount();\r
+                    break;\r
+                default:\r
+                    mgr.updateApiCallFailureCount();\r
+                    break;\r
             }\r
         }\r
     }\r
-}
\ No newline at end of file
+}\r