Removed all bytes read method from RemoteDirectory for safety

Signed-off-by: Vikas Bansal <43470111+vikasvb90@users.noreply.github.com>

server/src/main/java/org/opensearch/index/store/RemoteDirectory.java

@@ -146,16 +146,14 @@ public void onFailure(Exception e) {
     }
 
     /**
-     * Reads entire content from remote file. This should be used to read small files as it loads entire content
-     * in memory.
+     * Returns stream emitted from by blob object. Should be used with a closeable block.
+     *
      * @param fileName Name of file
-     * @return Content read
-     * @throws IOException if read fails with IO error
+     * @return Stream from the blob object
+     * @throws IOException if fetch of stream fails with IO error
      */
-    public byte[] readAllBytes(String fileName) throws IOException {
-        try (InputStream inputStream = blobContainer.readBlob(fileName)) {
-            return inputStream.readAllBytes();
-        }
+    public InputStream getBlobStream(String fileName) throws IOException {
+        return blobContainer.readBlob(fileName);
     }
 
     /**

server/src/main/java/org/opensearch/index/store/RemoteSegmentStoreDirectory.java

@@ -38,6 +38,7 @@
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.io.InputStream;
 import java.nio.file.NoSuchFileException;
 import java.util.Collection;
 import java.util.Collections;
@@ -190,8 +191,10 @@ public RemoteSegmentMetadata readLatestMetadataFile() throws IOException {
     }
 
     private RemoteSegmentMetadata readMetadataFile(String metadataFilename) throws IOException {
-        byte[] metadataBytes = remoteMetadataDirectory.readAllBytes(metadataFilename);
-        return metadataStreamWrapper.readStream(new ByteArrayIndexInput(metadataFilename, metadataBytes));
+        try (InputStream inputStream = remoteDataDirectory.getBlobStream(metadataFilename)) {
+            byte[] metadataBytes = inputStream.readAllBytes();
+            return metadataStreamWrapper.readStream(new ByteArrayIndexInput(metadataFilename, metadataBytes));
+        }
     }
 
     /**