add Unit Tests for RemoteSegmentMetadataHandler

Signed-off-by: Varun Bansal <[email protected]>

server/src/test/java/org/opensearch/index/store/remote/metadata/RemoteSegmentMetadataHandlerTests.java

@@ -0,0 +1,70 @@
+/*
+ * 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.index.store.remote.metadata;
+
+import org.apache.lucene.store.OutputStreamIndexOutput;
+import org.junit.Before;
+import org.opensearch.common.UUIDs;
+import org.opensearch.common.bytes.BytesReference;
+import org.opensearch.common.io.stream.BytesStreamOutput;
+import org.opensearch.common.lucene.store.ByteArrayIndexInput;
+import org.opensearch.test.OpenSearchTestCase;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Unit Tests for {@link RemoteSegmentMetadataHandler}
+ */
+public class RemoteSegmentMetadataHandlerTests extends OpenSearchTestCase {
+    private RemoteSegmentMetadataHandler remoteSegmentMetadataHandler;
+
+    @Before
+    public void setup() throws IOException {
+        remoteSegmentMetadataHandler = new RemoteSegmentMetadataHandler();
+    }
+
+    public void testReadContent() throws IOException {
+        BytesStreamOutput output = new BytesStreamOutput();
+        OutputStreamIndexOutput indexOutput = new OutputStreamIndexOutput("dummy bytes", "dummy stream", output, 4096);
+        Map<String, String> expectedOutput = getDummyData();
+        indexOutput.writeMapOfStrings(expectedOutput);
+        indexOutput.close();
+        RemoteSegmentMetadata metadata = remoteSegmentMetadataHandler.readContent(
+            new ByteArrayIndexInput("dummy bytes", BytesReference.toBytes(output.bytes()))
+        );
+        assertEquals(expectedOutput, metadata.toMapOfStrings());
+    }
+
+    public void testWriteContent() throws IOException {
+        BytesStreamOutput output = new BytesStreamOutput();
+        OutputStreamIndexOutput indexOutput = new OutputStreamIndexOutput("dummy bytes", "dummy stream", output, 4096);
+        Map<String, String> expectedOutput = getDummyData();
+        remoteSegmentMetadataHandler.writeContent(indexOutput, RemoteSegmentMetadata.fromMapOfStrings(expectedOutput));
+        indexOutput.close();
+        Map<String, String> actualOutput = new ByteArrayIndexInput("dummy bytes", BytesReference.toBytes(output.bytes()))
+            .readMapOfStrings();
+        assertEquals(expectedOutput, actualOutput);
+    }
+
+    private Map<String, String> getDummyData() {
+        Map<String, String> expectedOutput = new HashMap<>();
+        String prefix = "_0";
+        expectedOutput.put(
+            prefix + ".cfe",
+            prefix + ".cfe::" + prefix + ".cfe__" + UUIDs.base64UUID() + "::" + randomIntBetween(1000, 5000)
+        );
+        expectedOutput.put(
+            prefix + ".cfs",
+            prefix + ".cfs::" + prefix + ".cfs__" + UUIDs.base64UUID() + "::" + randomIntBetween(1000, 5000)
+        );
+        return expectedOutput;
+    }
+}