Add ErrorResponse to policy framework exceptions

The ErrorResponse object is now contained in Policy Framework
exceptions.

Issue-ID: POLICY-1095
Change-Id: Ib0ce6cdbbead939afefc4afa3f507eb1a28c4a5c
Signed-off-by: liamfallon <liam.fallon@est.tech>

3 files changed, 95 insertions, 1 deletions

diff --git a/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponse.java b/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponse.java
index b072ba1f6..88960f8ae 100644
--- a/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponse.java
+++ b/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponse.java
@@ -22,6 +22,7 @@ package org.onap.policy.models.errors.concepts;
 
 import com.google.gson.annotations.SerializedName;
 
+import java.io.Serializable;
 import java.util.List;
 
 import javax.ws.rs.core.Response;
@@ -36,7 +37,8 @@ import lombok.Data;
  *
  */
 @Data
-public class ErrorResponse {
+public class ErrorResponse implements Serializable {
+    private static final long serialVersionUID = 6760066094588944729L;
 
     @SerializedName("code")
     private Response.Status  responseCode;
diff --git a/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponseInfo.java b/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponseInfo.java
new file mode 100644
index 000000000..ed7104b04
--- /dev/null
+++ b/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponseInfo.java
@@ -0,0 +1,36 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2019 Nordix Foundation.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.models.errors.concepts;
+
+/**
+ * Interface implemented by Policy framework model exceptions to allow uniform reading of error responses.
+ *
+ * @author Liam Fallon (liam.fallon@est.tech)
+ */
+public interface ErrorResponseInfo {
+
+    /**
+     * Get the error response.
+     *
+     * @return the error response
+     */
+    public ErrorResponse getErrorResponse();
+}
diff --git a/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponseUtils.java b/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponseUtils.java
new file mode 100644
index 000000000..6346f9a90
--- /dev/null
+++ b/models-errors/src/main/java/org/onap/policy/models/errors/concepts/ErrorResponseUtils.java
@@ -0,0 +1,56 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2019 Nordix Foundation.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.models.errors.concepts;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Utility class for managing {@link ErrorResponse objects}
+ *
+ * @author Liam Fallon (liam.fallon@est.tech)
+ */
+public final class ErrorResponseUtils {
+    /**
+     * Private constructor used to prevent sub class instantiation.
+     */
+    private ErrorResponseUtils() {}
+
+    /**
+     * Store the cascaded messages from an exception and all its nested exceptions in an ErrorResponse object.
+     *
+     * @param throwable the top level exception
+     */
+    public static void getExceptionMessages(final ErrorResponse errorResponse, final Throwable throwable) {
+        errorResponse.setErrorMessage(throwable.getMessage());
+
+        List<String> cascascadedErrorMessages = new ArrayList<>();
+
+        for (Throwable t = throwable; t != null; t = t.getCause()) {
+            cascascadedErrorMessages.add(t.getMessage());
+        }
+
+        if (!cascascadedErrorMessages.isEmpty()) {
+            errorResponse.setErrorDetails(cascascadedErrorMessages);
+        }
+    }
+}
+