From 06cc8980f4a63c8e9333418f8e73fe520b4400e7 Mon Sep 17 00:00:00 2001
From: JinmingHu <jinmhu@microsoft.com>
Date: Thu, 3 Jun 2021 09:36:14 +0800
Subject: [PATCH] Add sample for transactional checksum (#2384)

---
 .../azure-storage-blobs/CMakeLists.txt        |  1 +
 .../sample/transactional_checksum.cpp         | 54 +++++++++++++++++++
 2 files changed, 55 insertions(+)
 create mode 100644 sdk/storage/azure-storage-blobs/sample/transactional_checksum.cpp

diff --git a/sdk/storage/azure-storage-blobs/CMakeLists.txt b/sdk/storage/azure-storage-blobs/CMakeLists.txt
index 6e3440736..8ac8b676e 100644
--- a/sdk/storage/azure-storage-blobs/CMakeLists.txt
+++ b/sdk/storage/azure-storage-blobs/CMakeLists.txt
@@ -115,6 +115,7 @@ if(BUILD_STORAGE_SAMPLES)
         sample/blob_getting_started.cpp
         sample/blob_list_operation.cpp
         sample/blob_sas.cpp
+        sample/transactional_checksum.cpp
   )
 
   target_link_libraries(azure-storage-sample PRIVATE azure-storage-blobs)
diff --git a/sdk/storage/azure-storage-blobs/sample/transactional_checksum.cpp b/sdk/storage/azure-storage-blobs/sample/transactional_checksum.cpp
new file mode 100644
index 000000000..e759db2ef
--- /dev/null
+++ b/sdk/storage/azure-storage-blobs/sample/transactional_checksum.cpp
@@ -0,0 +1,54 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+#include <iostream>
+
+#include <azure/storage/blobs.hpp>
+
+#include "samples_common.hpp"
+
+SAMPLE(TransactionalChecksum, TransactionalChecksum)
+void TransactionalChecksum()
+{
+  using namespace Azure::Storage::Blobs;
+
+  std::string containerName = "sample-container";
+  std::string blobName = "sample-blob";
+
+  auto containerClient
+      = BlobContainerClient::CreateFromConnectionString(GetConnectionString(), containerName);
+  containerClient.CreateIfNotExists();
+  BlockBlobClient blobClient = containerClient.GetBlockBlobClient(blobName);
+
+  // Upload 1MiB of data and verify with MD5
+  std::vector<uint8_t> buffer;
+  buffer.resize(1 * 1024 * 1024);
+  UploadBlockBlobOptions uploadOptions;
+  uploadOptions.TransactionalContentHash = Azure::Storage::ContentHash();
+  uploadOptions.TransactionalContentHash.Value().Algorithm = Azure::Storage::HashAlgorithm::Md5;
+  Azure::Core::Cryptography::Md5Hash md5Hash;
+  md5Hash.Append(buffer.data(), buffer.size());
+  uploadOptions.TransactionalContentHash.Value().Value = md5Hash.Final();
+  Azure::Core::IO::MemoryBodyStream bodyStream(buffer);
+  blobClient.Upload(bodyStream, uploadOptions);
+
+  // Download the data and verify with CRC64
+  DownloadBlobOptions downloadOptions;
+  downloadOptions.Range = Azure::Core::Http::HttpRange(); // Have to specify a range, and the range
+                                                          // cannot be larger than 4MiB
+  downloadOptions.Range.Value().Offset = 0;
+  downloadOptions.Range.Value().Length = buffer.size();
+  downloadOptions.RangeHashAlgorithm = Azure::Storage::HashAlgorithm::Crc64;
+  auto downloadResponse = blobClient.Download(downloadOptions);
+  buffer = downloadResponse.Value.BodyStream->ReadToEnd();
+  Azure::Storage::Crc64Hash crc64Hash;
+  crc64Hash.Append(buffer.data(), buffer.size());
+  if (crc64Hash.Final() != downloadResponse.Value.TransactionalContentHash.Value().Value)
+  {
+    std::cout << "CRC-64 mismatch" << std::endl;
+  }
+  else
+  {
+    std::cout << "CRC-64 match" << std::endl;
+  }
+}