Better error handling for decisions

Throw exceptions when requests cannot be created and return
error information back. Consolidated some code to avoid sonar
duplication issues.

Companion review to https://gerrit.onap.org/r/c/policy/models/+/103548

Issue-ID: POLICY-2242
Change-Id: Ic873af933dab82e3aeef6335f55939666be20385
Signed-off-by: Pamela Dragosh <pdragosh@research.att.com>

5 files changed, 20 insertions, 18 deletions

diff --git a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/ToscaPolicyTranslator.java b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/ToscaPolicyTranslator.java
index 47ff70f6..32b950b4 100644
--- a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/ToscaPolicyTranslator.java
+++ b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/ToscaPolicyTranslator.java
@@ -2,7 +2,7 @@
  * ============LICENSE_START=======================================================
  * ONAP
  * ================================================================================
- * Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
+ * Copyright (C) 2019-2020 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.
@@ -49,7 +49,7 @@ public interface ToscaPolicyTranslator {
      * @param request Incoming DecisionRequest
      * @return Xacml Request object
      */
-    Request convertRequest(DecisionRequest request);
+    Request convertRequest(DecisionRequest request) throws ToscaPolicyConversionException;
 
     /**
      * Implement this method to convert a Xacml Response
diff --git a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdBaseTranslator.java b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdBaseTranslator.java
index 34936b06..3ac57b7b 100644
--- a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdBaseTranslator.java
+++ b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdBaseTranslator.java
@@ -69,7 +69,7 @@ public abstract class StdBaseTranslator implements ToscaPolicyTranslator {
     }
 
     @Override
-    public Request convertRequest(DecisionRequest request) {
+    public Request convertRequest(DecisionRequest request) throws ToscaPolicyConversionException {
         return null;
     }
 
@@ -99,9 +99,10 @@ public abstract class StdBaseTranslator implements ToscaPolicyTranslator {
                 scanAdvice(xacmlResult.getAssociatedAdvice(), decisionResponse);
             } else {
                 //
-                // TODO we have to return an ErrorResponse object instead
+                // Return error information back
                 //
-                decisionResponse.setStatus("A better error message");
+                decisionResponse.setStatus("error");
+                decisionResponse.setMessage(xacmlResult.getStatus().getStatusMessage());
             }
         }
 
diff --git a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdCombinedPolicyResultsTranslator.java b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdCombinedPolicyResultsTranslator.java
index aba5e252..d9661829 100644
--- a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdCombinedPolicyResultsTranslator.java
+++ b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdCombinedPolicyResultsTranslator.java
@@ -127,17 +127,13 @@ public class StdCombinedPolicyResultsTranslator extends StdBaseTranslator {
     }
 
     @Override
-    public Request convertRequest(DecisionRequest request) {
+    public Request convertRequest(DecisionRequest request) throws ToscaPolicyConversionException {
         LOGGER.info("Converting Request {}", request);
         try {
             return RequestParser.parseRequest(StdCombinedPolicyRequest.createInstance(request));
         } catch (IllegalArgumentException | IllegalAccessException | DataTypeException e) {
-            LOGGER.error("Failed to convert DecisionRequest", e);
+            throw new ToscaPolicyConversionException("Failed to parse request", e);
         }
-        //
-        // TODO throw exception
-        //
-        return null;
     }
 
     /**
diff --git a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdMatchableTranslator.java b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdMatchableTranslator.java
index d5e2a395..7ca995e0 100644
--- a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdMatchableTranslator.java
+++ b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdMatchableTranslator.java
@@ -100,17 +100,13 @@ public class StdMatchableTranslator  extends StdBaseTranslator {
     }
 
     @Override
-    public Request convertRequest(DecisionRequest request) {
+    public Request convertRequest(DecisionRequest request) throws ToscaPolicyConversionException {
         LOGGER.info("Converting Request {}", request);
         try {
             return StdMatchablePolicyRequest.createInstance(request);
         } catch (XacmlApplicationException e) {
-            LOGGER.error("Failed to convert DecisionRequest", e);
+            throw new ToscaPolicyConversionException("Failed to convert DecisionRequest", e);
         }
-        //
-        // TODO throw exception
-        //
-        return null;
     }
 
     /**
diff --git a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdXacmlApplicationServiceProvider.java b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdXacmlApplicationServiceProvider.java
index 11271651..0fdd3a96 100644
--- a/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdXacmlApplicationServiceProvider.java
+++ b/applications/common/src/main/java/org/onap/policy/pdp/xacml/application/common/std/StdXacmlApplicationServiceProvider.java
@@ -232,7 +232,16 @@ public abstract class StdXacmlApplicationServiceProvider implements XacmlApplica
         //
         // Convert to a XacmlRequest
         //
-        Request xacmlRequest = this.getTranslator().convertRequest(request);
+        Request xacmlRequest;
+        try {
+            xacmlRequest = this.getTranslator().convertRequest(request);
+        } catch (ToscaPolicyConversionException e) {
+            LOGGER.error("Failed to convert request", e);
+            DecisionResponse response = new DecisionResponse();
+            response.setStatus("error");
+            response.setMessage(e.getLocalizedMessage());
+            return Pair.of(response, null);
+        }
         //
         // Now get a decision
         //