Replace metadata keys in OpenSearchException during serialization and deserialization (#905)

Signed-off-by: Vlad Rozov <vrozov@users.noreply.github.com>

qa/mixed-cluster/src/test/java/org/opensearch/backwards/ExceptionIT.java

@@ -0,0 +1,61 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.backwards;
+
+import org.apache.http.util.EntityUtils;
+import org.opensearch.Version;
+import org.opensearch.client.Node;
+import org.opensearch.client.Request;
+import org.opensearch.client.Response;
+import org.opensearch.client.ResponseException;
+import org.opensearch.test.rest.OpenSearchRestTestCase;
+import org.opensearch.test.rest.yaml.ObjectPath;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Map;
+
+import static org.apache.http.HttpStatus.SC_NOT_FOUND;
+
+public class ExceptionIT extends OpenSearchRestTestCase {
+    public void testOpensearchException() throws Exception {
+        logClusterNodes();
+
+        Request request = new Request("GET", "/no_such_index");
+
+        for (Node node : client().getNodes()) {
+            try {
+                client().setNodes(Collections.singletonList(node));
+                logger.info("node: {}", node.getHost());
+                client().performRequest(request);
+                fail();
+            } catch (ResponseException e) {
+                logger.debug(e.getMessage());
+                Response response = e.getResponse();
+                assertEquals(SC_NOT_FOUND, response.getStatusLine().getStatusCode());
+                assertEquals("no_such_index", ObjectPath.createFromResponse(response).evaluate("error.index"));
+            }
+        }
+    }
+
+    private void logClusterNodes() throws IOException {
+        ObjectPath objectPath = ObjectPath.createFromResponse(client().performRequest(new Request("GET", "_nodes")));
+        Map<String, ?> nodes = objectPath.evaluate("nodes");
+        String master = EntityUtils.toString(client().performRequest(new Request("GET", "_cat/master?h=id")).getEntity()).trim();
+        logger.info("cluster discovered: master id='{}'", master);
+        for (String id : nodes.keySet()) {
+            logger.info("{}: id='{}', name='{}', version={}",
+                objectPath.evaluate("nodes." + id + ".http.publish_address"),
+                id,
+                objectPath.evaluate("nodes." + id + ".name"),
+                Version.fromString(objectPath.evaluate("nodes." + id + ".version"))
+            );
+        }
+    }
+}

server/src/main/java/org/opensearch/OpenSearchException.java

@@ -61,6 +61,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
 import static java.util.Collections.emptyMap;
@@ -108,6 +109,10 @@ public class OpenSearchException extends RuntimeException implements ToXContentF
 
     private static final Map<Integer, CheckedFunction<StreamInput, ? extends OpenSearchException, IOException>> ID_TO_SUPPLIER;
     private static final Map<Class<? extends OpenSearchException>, OpenSearchExceptionHandle> CLASS_TO_OPENSEARCH_EXCEPTION_HANDLE;
+
+    private static final Pattern OS_METADATA = Pattern.compile("^opensearch\\.");
+    private static final Pattern ES_METADATA = Pattern.compile("^es\\.");
+
     private final Map<String, List<String>> metadata = new HashMap<>();
     private final Map<String, List<String>> headers = new HashMap<>();
 
@@ -150,7 +155,16 @@ public class OpenSearchException extends RuntimeException implements ToXContentF
         super(in.readOptionalString(), in.readException());
         readStackTrace(this, in);
         headers.putAll(in.readMapOfLists(StreamInput::readString, StreamInput::readString));
-        metadata.putAll(in.readMapOfLists(StreamInput::readString, StreamInput::readString));
+        metadata.putAll(in.readMapOfLists(OpenSearchException::readAndReplace, StreamInput::readString));
+    }
+
+    private static String readAndReplace(StreamInput in) throws IOException {
+        String str = in.readString();
+        return in.getVersion().onOrBefore(LegacyESVersion.V_7_10_2) ? ES_METADATA.matcher(str).replaceFirst("opensearch.") : str;
+    }
+
+    private static void replaceAndWrite(StreamOutput out, String str) throws IOException {
+        out.writeString(out.getVersion().onOrBefore(LegacyESVersion.V_7_10_2) ? OS_METADATA.matcher(str).replaceFirst("es.") : str);
     }
 
     /**
@@ -293,7 +307,7 @@ public class OpenSearchException extends RuntimeException implements ToXContentF
         out.writeException(this.getCause());
         writeStackTraces(this, out, StreamOutput::writeException);
         out.writeMapOfLists(headers, StreamOutput::writeString, StreamOutput::writeString);
-        out.writeMapOfLists(metadata, StreamOutput::writeString, StreamOutput::writeString);
+        out.writeMapOfLists(metadata, OpenSearchException::replaceAndWrite, StreamOutput::writeString);
     }
 
     public static OpenSearchException readException(StreamInput input, int id) throws IOException {