addressing review comments

Author: Local Merge

sdk/storage/azure-storage-common/src/main/java/com/azure/storage/common/policy/DecodedResponse.java

@@ -42,8 +42,7 @@ class DecodedResponse extends HttpResponse {
         super(httpResponse.getRequest());
         this.originalResponse = httpResponse;
         this.decodedBody = decodedBody;
-        HttpHeaders headers = new HttpHeaders();
-        httpResponse.getHeaders().stream().forEach(h -> headers.set(h.getName(), h.getValue()));
+        HttpHeaders headers = new HttpHeaders(httpResponse.getHeaders());
         headers.set(HttpHeaderName.CONTENT_LENGTH, String.valueOf(decodedContentLength));
         this.adjustedHeaders = headers;
     }

sdk/storage/azure-storage-common/src/test/java/com/azure/storage/common/policy/StorageContentValidationDecoderPolicyTests.java

@@ -0,0 +1,131 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package com.azure.storage.common.policy;
+
+import com.azure.core.http.HttpHeaderName;
+import com.azure.core.http.HttpHeaders;
+import com.azure.core.http.HttpMethod;
+import com.azure.core.http.HttpPipeline;
+import com.azure.core.http.HttpPipelineBuilder;
+import com.azure.core.http.HttpRequest;
+import com.azure.core.http.HttpResponse;
+import com.azure.core.test.http.MockHttpResponse;
+import com.azure.core.util.Context;
+import com.azure.core.util.FluxUtil;
+import com.azure.storage.common.implementation.Constants;
+import com.azure.storage.common.implementation.contentvalidation.StructuredMessageConstants;
+import com.azure.storage.common.implementation.contentvalidation.StructuredMessageEncoder;
+import com.azure.storage.common.implementation.contentvalidation.StructuredMessageFlags;
+import org.junit.jupiter.api.Test;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.nio.ByteBuffer;
+import java.util.Objects;
+import java.util.concurrent.ThreadLocalRandom;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+public class StorageContentValidationDecoderPolicyTests {
+
+    private static HttpRequest getRequest() {
+        try {
+            return new HttpRequest(HttpMethod.GET, new URL("http://example.com/blob"));
+        } catch (MalformedURLException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private static byte[] encodeToBytes(byte[] data, int segmentSize, StructuredMessageFlags flags) throws IOException {
+        StructuredMessageEncoder encoder = new StructuredMessageEncoder(data.length, segmentSize, flags);
+        Flux<ByteBuffer> flux = encoder.encode(ByteBuffer.wrap(data));
+        ByteBuffer encoded
+            = ByteBuffer.wrap(Objects.requireNonNull(FluxUtil.collectBytesInByteBufferStream(flux).block()));
+        byte[] bytes = new byte[encoded.remaining()];
+        encoded.get(bytes);
+        return bytes;
+    }
+
+    @Test
+    public void contentLengthIsOverriddenToDecodedSizeWhenDecodingApplied() throws IOException {
+        byte[] payload = new byte[64];
+        ThreadLocalRandom.current().nextBytes(payload);
+
+        byte[] encoded = encodeToBytes(payload, 64, StructuredMessageFlags.STORAGE_CRC64);
+        long encodedLen = encoded.length;
+        long decodedLen = payload.length;
+
+        HttpHeaders responseHeaders = new HttpHeaders().set(HttpHeaderName.CONTENT_LENGTH, String.valueOf(encodedLen))
+            .set(Constants.HeaderConstants.STRUCTURED_BODY_TYPE_HEADER_NAME,
+                StructuredMessageConstants.STRUCTURED_BODY_TYPE_VALUE)
+            .set(Constants.HeaderConstants.STRUCTURED_CONTENT_LENGTH_HEADER_NAME, String.valueOf(decodedLen));
+
+        HttpPipeline pipeline = new HttpPipelineBuilder().policies(new StorageContentValidationDecoderPolicy())
+            .httpClient(request -> Mono.just(new MockHttpResponse(request, 200, responseHeaders, encoded)))
+            .build();
+
+        Context ctx = new Context(StructuredMessageConstants.STRUCTURED_MESSAGE_DECODING_CONTEXT_KEY, true);
+        HttpResponse response = pipeline.send(getRequest(), ctx).block();
+
+        assertNotNull(response);
+        assertEquals(String.valueOf(decodedLen), response.getHeaders().getValue(HttpHeaderName.CONTENT_LENGTH));
+    }
+
+    @Test
+    public void contentLengthMatchesActualDecodedBodySize() throws IOException {
+        byte[] payload = new byte[128];
+        ThreadLocalRandom.current().nextBytes(payload);
+
+        byte[] encoded = encodeToBytes(payload, 64, StructuredMessageFlags.STORAGE_CRC64);
+        long encodedLen = encoded.length;
+        long decodedLen = payload.length;
+
+        HttpHeaders responseHeaders = new HttpHeaders().set(HttpHeaderName.CONTENT_LENGTH, String.valueOf(encodedLen))
+            .set(Constants.HeaderConstants.STRUCTURED_BODY_TYPE_HEADER_NAME,
+                StructuredMessageConstants.STRUCTURED_BODY_TYPE_VALUE)
+            .set(Constants.HeaderConstants.STRUCTURED_CONTENT_LENGTH_HEADER_NAME, String.valueOf(decodedLen));
+
+        HttpPipeline pipeline = new HttpPipelineBuilder().policies(new StorageContentValidationDecoderPolicy())
+            .httpClient(request -> Mono.just(new MockHttpResponse(request, 200, responseHeaders, encoded)))
+            .build();
+
+        Context ctx = new Context(StructuredMessageConstants.STRUCTURED_MESSAGE_DECODING_CONTEXT_KEY, true);
+        HttpResponse response = pipeline.send(getRequest(), ctx).block();
+
+        assertNotNull(response);
+        assertEquals(String.valueOf(decodedLen), response.getHeaders().getValue(HttpHeaderName.CONTENT_LENGTH));
+
+        // Consume the body and verify it matches the original payload — the reported Content-Length
+        // must equal the actual number of bytes produced by the decoder.
+        byte[] body = Objects.requireNonNull(FluxUtil.collectBytesInByteBufferStream(response.getBody()).block());
+        assertEquals(decodedLen, body.length);
+        assertArrayEquals(payload, body);
+    }
+
+    @Test
+    public void contentLengthIsUnchangedWhenDecodingNotApplied() throws IOException {
+        byte[] payload = new byte[64];
+        ThreadLocalRandom.current().nextBytes(payload);
+
+        byte[] encoded = encodeToBytes(payload, 64, StructuredMessageFlags.STORAGE_CRC64);
+        long encodedLen = encoded.length;
+
+        HttpHeaders responseHeaders = new HttpHeaders().set(HttpHeaderName.CONTENT_LENGTH, String.valueOf(encodedLen));
+
+        HttpPipeline pipeline = new HttpPipelineBuilder().policies(new StorageContentValidationDecoderPolicy())
+            .httpClient(request -> Mono.just(new MockHttpResponse(request, 200, responseHeaders, encoded)))
+            .build();
+
+        // No decoding context flag set — policy should pass the response through unchanged.
+        HttpResponse response = pipeline.send(getRequest()).block();
+
+        assertNotNull(response);
+        assertEquals(String.valueOf(encodedLen), response.getHeaders().getValue(HttpHeaderName.CONTENT_LENGTH));
+    }
+}