From a7d26247e84dc05dd8580f40b9c8dc693554d898 Mon Sep 17 00:00:00 2001
From: szczepanczykd <48957041+szczepanczykd@users.noreply.github.com>
Date: Thu, 11 May 2023 19:22:58 +0200
Subject: [PATCH] fix: handle String error deserialization for ErrorCause
 object (#301) (#476) (#478)

* fix: handle String error deserialization for ErrorCause object (#301)



* update CHANGELOG.md



---------

Signed-off-by: Dominik Szczepanczyk <szczepanczyk.dominik@gmail.com>
---
 CHANGELOG.md                                  |  2 ++
 .../opensearch/_types/ErrorResponse.java      | 22 ++++++++++++++++++-
 .../integTest/AbstractIndicesClientIT.java    | 17 ++++++++++++++
 3 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index c8a2bdc407..03096472b9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -100,6 +100,8 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - Do not double-wrap OpenSearchException on error ([#323](https://github.com/opensearch-project/opensearch-java/pull/323))
 - Fix AwsSdk2TransportOptions.responseCompression ([#322](https://github.com/opensearch-project/opensearch-java/pull/322))
 - Fix missing Highlight and SourceConfig in the MultisearchBody ([#442](https://github.com/opensearch-project/opensearch-java/pull/442))
+- Fix parsing /_alias error response for not existing alias ([#476](https://github.com/opensearch-project/opensearch-java/pull/476))
+
 
 ### Security
 
diff --git a/java-client/src/main/java/org/opensearch/client/opensearch/_types/ErrorResponse.java b/java-client/src/main/java/org/opensearch/client/opensearch/_types/ErrorResponse.java
index 2f71c65905..a3e63ec7dc 100644
--- a/java-client/src/main/java/org/opensearch/client/opensearch/_types/ErrorResponse.java
+++ b/java-client/src/main/java/org/opensearch/client/opensearch/_types/ErrorResponse.java
@@ -42,10 +42,12 @@
 import org.opensearch.client.json.JsonpSerializable;
 import org.opensearch.client.json.ObjectBuilderDeserializer;
 import org.opensearch.client.json.ObjectDeserializer;
+import org.opensearch.client.json.UnionDeserializer;
 import org.opensearch.client.util.ApiTypeHelper;
 import org.opensearch.client.util.ObjectBuilder;
 import org.opensearch.client.util.ObjectBuilderBase;
 import jakarta.json.stream.JsonGenerator;
+
 import java.util.function.Function;
 
 // typedef: _types.ErrorResponseBase
@@ -57,6 +59,11 @@
  */
 @JsonpDeserializable
 public class ErrorResponse implements JsonpSerializable {
+
+	private enum Kind {
+		OBJECT,
+		STRING
+	}
 	private final ErrorCause error;
 
 	private final int status;
@@ -164,9 +171,22 @@ public ErrorResponse build() {
 
 	protected static void setupErrorResponseDeserializer(ObjectDeserializer<ErrorResponse.Builder> op) {
 
-		op.add(Builder::error, ErrorCause._DESERIALIZER, "error");
+		op.add(Builder::error, buildErrorCauseDeserializers(), "error");
 		op.add(Builder::status, JsonpDeserializer.integerDeserializer(), "status");
 
 	}
 
+	protected static JsonpDeserializer<ErrorCause> buildErrorCauseDeserializers() {
+		return new UnionDeserializer.Builder<>(ErrorResponse::getErrorCause, false)
+				.addMember(Kind.OBJECT, ErrorCause._DESERIALIZER)
+				.addMember(Kind.STRING, JsonpDeserializer.stringDeserializer())
+				.build();
+	}
+
+	private static ErrorCause getErrorCause(Kind kind, Object errorCause) {
+		return Kind.STRING.equals(kind) ?
+				ErrorCause.of(builder -> builder.type("string_error").reason((String) errorCause)) :
+				(ErrorCause) errorCause;
+	}
+
 }
diff --git a/java-client/src/test/java/org/opensearch/client/opensearch/integTest/AbstractIndicesClientIT.java b/java-client/src/test/java/org/opensearch/client/opensearch/integTest/AbstractIndicesClientIT.java
index f17d7b6167..869e63cc1c 100644
--- a/java-client/src/test/java/org/opensearch/client/opensearch/integTest/AbstractIndicesClientIT.java
+++ b/java-client/src/test/java/org/opensearch/client/opensearch/integTest/AbstractIndicesClientIT.java
@@ -15,6 +15,8 @@
 import org.opensearch.client.opensearch.indices.DataStream;
 import org.opensearch.client.opensearch.indices.DataStreamsStatsResponse;
 import org.opensearch.client.opensearch.indices.DeleteDataStreamResponse;
+import org.opensearch.client.opensearch.indices.GetAliasRequest;
+import org.opensearch.client.opensearch.indices.GetAliasResponse;
 import org.opensearch.client.opensearch.indices.GetDataStreamResponse;
 import org.opensearch.client.opensearch.indices.GetIndexRequest;
 import org.opensearch.client.opensearch.indices.GetIndexResponse;
@@ -188,4 +190,19 @@ public void testDataStream() throws IOException {
             assertEquals(ex.status(), 404);
         }
     }
+
+    public void testGetNotExistingIndexAlias() throws Exception {
+        String notExistingIndexAlias = "alias_not_exists";
+        GetAliasRequest aliasRequest = new GetAliasRequest.Builder().name(notExistingIndexAlias).build();
+        try {
+            GetAliasResponse response = javaClient().indices().getAlias(aliasRequest);
+            fail();
+        } catch (OpenSearchException ex) {
+            assertNotNull(ex);
+            assertEquals(ex.status(), 404);
+            assertEquals(ex.getMessage(),
+                    "Request failed: [string_error] " +
+                            "alias [alias_not_exists] missing");
+        }
+    }
 }
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