Address review comments

Author: RusJaI

Diff for: components/apimgt/org.wso2.carbon.apimgt.gateway/src/main/java/org/wso2/carbon/apimgt/gateway/handlers/security/keys/APIKeyValidatorClient.java

@@ -56,7 +56,7 @@ public APIKeyValidationInfoDTO getAPIKeyData(String context, String apiVersion,
         } catch (APIKeyMgtException | APIManagementException e) {
             log.error("Error while retrieving data from datastore", e);
             throw new APISecurityException(APISecurityConstants.API_AUTH_GENERAL_ERROR,
-                    "Error while retrieving data from datastore", e);
+                    e.getMessage(), e);
         }
 
     }

Diff for: components/apimgt/org.wso2.carbon.apimgt.gateway/src/main/java/org/wso2/carbon/apimgt/gateway/handlers/security/keys/WSAPIKeyDataStore.java

@@ -22,6 +22,7 @@
 import org.wso2.carbon.apimgt.gateway.MethodStats;
 import org.wso2.carbon.apimgt.gateway.handlers.security.APISecurityConstants;
 import org.wso2.carbon.apimgt.gateway.handlers.security.APISecurityException;
+import org.wso2.carbon.apimgt.impl.APIConstants;
 import org.wso2.carbon.apimgt.impl.dto.APIKeyValidationInfoDTO;
 import org.wso2.carbon.apimgt.keymgt.model.entity.Scope;
 import org.wso2.carbon.apimgt.keymgt.service.TokenValidationContext;
@@ -53,6 +54,10 @@ public APIKeyValidationInfoDTO getAPIKeyData(String context, String apiVersion,
             return client.getAPIKeyData(context, apiVersion, apiKey, requiredAuthenticationLevel,
                     matchingResource, httpVerb, tenantDomain, keyManagers);
         } catch (APISecurityException ex) {
+            if (ex.getMessage().equalsIgnoreCase(APIConstants.JWT_GENERATION_ERROR)) {
+                throw new APISecurityException(ex.getErrorCode(),
+                        APISecurityConstants.API_AUTH_GENERAL_ERROR_MESSAGE, ex);
+            }
             throw new APISecurityException(ex.getErrorCode(),
                     "Resource forbidden", ex);
         } catch (Exception e) {

Diff for: components/apimgt/org.wso2.carbon.apimgt.impl/src/main/java/org/wso2/carbon/apimgt/impl/APIConstants.java

@@ -1913,6 +1913,8 @@ public enum RegistryResourceTypesForUI {
     public static final String MSG_TIER_RET_ERROR = "Error while retrieving API tiers from registry";
     public static final String MSG_MALFORMED_XML_ERROR = "Malformed XML found in the API tier policy resource";
 
+    public static final String JWT_GENERATION_ERROR = "Error occurred while generating JWT";
+
     //Doc search related constants
 
     public static final String PUBLISHER_CLIENT = "Publisher";

Diff for: components/apimgt/org.wso2.carbon.apimgt.keymgt/src/main/java/org/wso2/carbon/apimgt/keymgt/handlers/AbstractKeyValidationHandler.java

@@ -133,16 +133,15 @@ protected boolean hasTokenRequiredAuthLevel(String authScheme,
     @Override
     public boolean generateConsumerToken(TokenValidationContext validationContext) throws APIKeyMgtException {
 
-        String jwt;
+        String jwt = null;
         try {
             jwt = getCachedJWTToken(validationContext);
         } catch (APIManagementException e) {
             if (!(ServiceReferenceHolder.getInstance().getAPIManagerConfigurationService().getAPIManagerConfiguration()
                     .getJwtConfigurationDto().isContinueOnClaimRetrievalFailure())) {
-                throw new APIKeyMgtException("Error occurred while generating JWT", e);
+                throw new APIKeyMgtException(APIConstants.JWT_GENERATION_ERROR, e);
             } else {
                 log.error("Error occurred while generating JWT. ", e);
-                return false;
             }
         }
         validationContext.getValidationInfoDTO().setEndUserToken(jwt);