Add StatusProto.toStatusException overload to accept Throwable

Author: rtadepalli

protobuf/src/main/java/io/grpc/protobuf/StatusProto.java

@@ -103,6 +103,25 @@ public static StatusException toStatusException(
  return toStatus(statusProto).asException(toMetadata(statusProto, metadata));
  }
 
+ /**
+ * Convert a {@link com.google.rpc.Status} instance to a {@link StatusException} with additional
+ * metadata and the root exception thrown.
+ *
+ * <p>The returned {@link StatusException} will wrap a {@link Status} whose code and description
+ * are set from the code and message in {@code statusProto}. {@code statusProto} will be
+ * serialized and added to {@code metadata}. {@code metadata} will be set as the metadata of the
+ * returned {@link StatusException}. The {@link Throwable} is the exception that is set as the
+ * {@code cause} of the returned {@link StatusException}.
+ *
+ * @throws IllegalArgumentException if the value of {@code statusProto.getCode()} is not a valid
+ * gRPC status code.
+ * @since 1.3.0
+ */
+ public static StatusException toStatusException(
+ com.google.rpc.Status statusProto, Metadata metadata, Throwable cause) {
+ return toStatus(statusProto).withCause(cause).asException(toMetadata(statusProto, metadata));
+ }
+
  private static Status toStatus(com.google.rpc.Status statusProto) {
  Status status = Status.fromCodeValue(statusProto.getCode());
  checkArgument(status.getCode().value() == statusProto.getCode(), "invalid status code");

protobuf/src/test/java/io/grpc/protobuf/StatusProtoTest.java

@@ -176,6 +176,15 @@ public void fromThrowable_shouldReturnNullIfNoEmbeddedStatus() {
  assertNull(StatusProto.fromThrowable(nestedSe));
  }
 
+ @Test
+ public void toStatusExceptionWithMetadataAndCause_shouldCaptureCause() {
+ StatusException se = StatusProto.toStatusException(STATUS_PROTO, new Metadata(),
+ new RuntimeException("This is a test exception."));
+
+ assertNotNull(se.getCause());
+ assertEquals(se.getCause().getMessage(), "This is a test exception.");
+ }
+
  private static final Metadata.Key<String> METADATA_KEY =
  Metadata.Key.of("test-metadata", Metadata.ASCII_STRING_MARSHALLER);
  private static final String METADATA_VALUE = "test metadata value";