fix: set instruction file content length (#501)

* fix: set instruction file content length

Author: kessplas

src/main/java/software/amazon/encryption/s3/internal/InstructionFileConfig.java

@@ -1,11 +1,5 @@
 package software.amazon.encryption.s3.internal;
 
-import static software.amazon.encryption.s3.S3EncryptionClientUtilities.DEFAULT_INSTRUCTION_FILE_SUFFIX;
-import static software.amazon.encryption.s3.internal.MetadataKeyConstants.INSTRUCTION_FILE;
-
-import java.util.HashMap;
-import java.util.Map;
-
 import software.amazon.awssdk.core.ResponseInputStream;
 import software.amazon.awssdk.core.async.AsyncRequestBody;
 import software.amazon.awssdk.core.async.AsyncResponseTransformer;
@@ -18,6 +12,12 @@
 import software.amazon.awssdk.services.s3.model.PutObjectResponse;
 import software.amazon.encryption.s3.S3EncryptionClientException;
 
+import java.util.HashMap;
+import java.util.Map;
+
+import static software.amazon.encryption.s3.S3EncryptionClientUtilities.DEFAULT_INSTRUCTION_FILE_SUFFIX;
+import static software.amazon.encryption.s3.internal.MetadataKeyConstants.INSTRUCTION_FILE;
+
 /**
  * Provides configuration options for instruction file behaviors.
  */
@@ -65,8 +65,10 @@ PutObjectResponse putInstructionFile(PutObjectRequest request, String instructio
         instFileMetadata.put(INSTRUCTION_FILE, "");
 
         // Use toBuilder to keep all other fields the same as the actual request
+        // but set the content length, key, and metadata appropriately for the instruction file
         final PutObjectRequest instPutRequest = request.toBuilder()
           .key(request.key() + instructionFileSuffix)
+          .contentLength((long) instructionFileContent.getBytes().length)
           .metadata(instFileMetadata)
           .build();
         switch (_clientType) {

src/test/java/software/amazon/encryption/s3/internal/InstructionFileConfigUploadTest.java

@@ -0,0 +1,75 @@
+// Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+package software.amazon.encryption.s3.internal;
+
+import org.junit.jupiter.api.Test;
+import org.mockito.ArgumentCaptor;
+import software.amazon.awssdk.core.async.AsyncRequestBody;
+import software.amazon.awssdk.core.sync.RequestBody;
+import software.amazon.awssdk.services.s3.S3AsyncClient;
+import software.amazon.awssdk.services.s3.S3Client;
+import software.amazon.awssdk.services.s3.model.PutObjectRequest;
+
+import java.util.concurrent.CompletableFuture;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.*;
+
+class InstructionFileConfigUploadTest {
+
+  @Test
+  void uploadInstructionFileWithSetContentLengthSyncClient() {
+    // Create a mock for the S3 client
+    S3Client mockedS3Client = mock(S3Client.class);
+    // The argument captor is used to capture the PutObjectRequest passed to the putObject method
+    ArgumentCaptor<PutObjectRequest> instructionFilePutCaptor = ArgumentCaptor.forClass(PutObjectRequest.class);
+
+    // Create the InstructionFileConfig with the mocked S3 client
+    InstructionFileConfig instructionFileConfig = InstructionFileConfig.builder()
+            .instructionFileClient(mockedS3Client)
+            .enableInstructionFilePutObject(true)
+            .build();
+
+    // Build some data for the test
+    PutObjectRequest putObjectRequest = PutObjectRequest.builder()
+            .key("someKey").build();
+    String instructionFileContent = "some content that fakes an instruction file";
+
+    // call the actual method under test
+    instructionFileConfig.putInstructionFile(putObjectRequest, instructionFileContent);
+
+    // Verify that the putObject method was called and the captured request has the correct content length
+    verify(mockedS3Client).putObject(instructionFilePutCaptor.capture(), any(RequestBody.class));
+    assertEquals(instructionFileContent.getBytes().length, instructionFilePutCaptor.getValue().contentLength());
+  }
+
+  @Test
+  void uploadInstructionFileWithSetContentLengthAsyncClient() {
+    // Create a mock for the S3 client
+    S3AsyncClient mockedS3Client = mock(S3AsyncClient.class);
+    // The async putObject method returns a CompletableFuture, so we need to mock that behavior
+    when(mockedS3Client.putObject(any(PutObjectRequest.class), any(AsyncRequestBody.class)))
+            .thenReturn(CompletableFuture.completedFuture(null));
+    // The argument captor is used to capture the PutObjectRequest passed to the putObject method
+    ArgumentCaptor<PutObjectRequest> instructionFilePutCaptor = ArgumentCaptor.forClass(PutObjectRequest.class);
+
+    // Create the InstructionFileConfig with the mocked S3 async client
+    InstructionFileConfig instructionFileConfig = InstructionFileConfig.builder()
+            .instructionFileAsyncClient(mockedS3Client)
+            .enableInstructionFilePutObject(true)
+            .build();
+
+    // Build some data for the test
+    PutObjectRequest putObjectRequest = PutObjectRequest.builder()
+            .key("someKey").build();
+    String instructionFileContent = "some content that fakes an instruction file";
+
+    // Call the actual method under test
+    instructionFileConfig.putInstructionFile(putObjectRequest, instructionFileContent);
+
+    // Verify that the putObject method was called and the captured request has the correct content length
+    verify(mockedS3Client).putObject(instructionFilePutCaptor.capture(), any(AsyncRequestBody.class));
+    assertEquals(instructionFileContent.getBytes().length, instructionFilePutCaptor.getValue().contentLength());
+  }
+}