[Client encryption]: Adds support for Brotli compression

Microsoft.Azure.Cosmos.Encryption.Custom/src/CompressionOptions.cs

@@ -33,11 +33,7 @@ public enum CompressionAlgorithm
         /// <summary>
         /// Gets or sets compression algorithm.
         /// </summary>
-#if NET8_0_OR_GREATER
-        public CompressionAlgorithm Algorithm { get; set; } = CompressionAlgorithm.Brotli;
-#else
         public CompressionAlgorithm Algorithm { get; set; } = CompressionAlgorithm.None;
-#endif
 
         /// <summary>
         /// Gets or sets compression level.

Microsoft.Azure.Cosmos.Encryption.Custom/src/Transformation/BrotliCompressor.cs

@@ -4,10 +4,11 @@
 
 namespace Microsoft.Azure.Cosmos.Encryption.Custom.Transformation
 {
-#if ENCRYPTION_CUSTOM_PREVIEW && NET8_0_OR_GREATER
+#if NET8_0_OR_GREATER
 
     using System;
     using System.Buffers;
+    using System.Collections.Generic;
     using System.IO.Compression;
 
     internal class BrotliCompressor : IDisposable
@@ -44,13 +45,13 @@ public BrotliCompressor(CompressionLevel compressionLevel)
             this.encoder = new BrotliEncoder(BrotliCompressor.GetQualityFromCompressionLevel(compressionLevel), DefaultWindow);
         }
 
-        public virtual int Compress(EncryptionProperties properties, string path, byte[] bytes, int length, byte[] outputBytes)
+        public virtual int Compress(Dictionary<string, int> compressedPaths, string path, byte[] bytes, int length, byte[] outputBytes)
         {
             OperationStatus status = this.encoder.Compress(bytes.AsSpan(0, length), outputBytes, out int bytesConsumed, out int bytesWritten, true);
 
             ThrowIfFailure(status, length, bytesConsumed);
 
-            properties.CompressedEncryptedPaths[path] = length;
+            compressedPaths[path] = length;
 
             return bytesWritten;
         }

Microsoft.Azure.Cosmos.Encryption.Custom/src/Transformation/MdeEncryptionProcessor.Preview.cs

@@ -35,19 +35,13 @@ public async Task<Stream> EncryptAsync(
 
             DataEncryptionKey encryptionKey = await encryptor.GetEncryptionKeyAsync(encryptionOptions.DataEncryptionKeyId, encryptionOptions.EncryptionAlgorithm, token);
 
-            EncryptionProperties encryptionProperties = new (
-                encryptionFormatVersion: 4,
-                encryptionOptions.EncryptionAlgorithm,
-                encryptionOptions.DataEncryptionKeyId,
-                encryptedData: null,
-                pathsEncrypted,
-                encryptionOptions.CompressionOptions.Algorithm,
-                new Dictionary<string, int>());
+            bool compressionEnabled = encryptionOptions.CompressionOptions.Algorithm != CompressionOptions.CompressionAlgorithm.None;
 
 #if NET8_0_OR_GREATER
             BrotliCompressor compressor = encryptionOptions.CompressionOptions.Algorithm == CompressionOptions.CompressionAlgorithm.Brotli
                 ? new BrotliCompressor(encryptionOptions.CompressionOptions.CompressionLevel) : null;
 #endif
+            Dictionary<string, int> compressedPaths = new ();
 
             foreach (string pathToEncrypt in encryptionOptions.PathsToEncrypt)
             {
@@ -78,7 +72,7 @@ public async Task<Stream> EncryptAsync(
                 if (compressor != null && (processedBytesLength >= encryptionOptions.CompressionOptions.MinimalCompressedLength))
                 {
                     byte[] compressedBytes = arrayPoolManager.Rent(BrotliCompressor.GetMaxCompressedSize(processedBytesLength));
-                    processedBytesLength = compressor.Compress(encryptionProperties, pathToEncrypt, processedBytes, processedBytesLength, compressedBytes);
+                    processedBytesLength = compressor.Compress(compressedPaths, pathToEncrypt, processedBytes, processedBytesLength, compressedBytes);
                     processedBytes = compressedBytes;
                 }
 #endif
@@ -93,6 +87,14 @@ public async Task<Stream> EncryptAsync(
 #if NET8_0_OR_GREATER
             compressor?.Dispose();
 #endif
+            EncryptionProperties encryptionProperties = new (
+                encryptionFormatVersion: compressionEnabled ? 4 : 3,
+                encryptionOptions.EncryptionAlgorithm,
+                encryptionOptions.DataEncryptionKeyId,
+                encryptedData: null,
+                pathsEncrypted,
+                encryptionOptions.CompressionOptions.Algorithm,
+                compressedPaths);
 
             itemJObj.Add(Constants.EncryptedInfo, JObject.FromObject(encryptionProperties));
 #if NET8_0_OR_GREATER

Microsoft.Azure.Cosmos.Encryption.Custom/tests/Microsoft.Azure.Cosmos.Encryption.Custom.Tests/EncryptionPropertiesTests.cs

@@ -12,7 +12,7 @@ public class EncryptionPropertiesTests
         [TestMethod]
         public void Ctor_AssignsAllMandatoryProperties()
         {
-            EncryptionProperties properties = new EncryptionProperties(
+            EncryptionProperties properties = new (
                 11,
                 "algorithm",
                 "dek-id",
@@ -32,7 +32,7 @@ public void Ctor_AssignsAllMandatoryProperties()
         [TestMethod]
         public void Ctor_AssignsAllProperties()
         {
-            EncryptionProperties properties = new EncryptionProperties(
+            EncryptionProperties properties = new (
                 11,
                 "algorithm",
                 "dek-id",

Microsoft.Azure.Cosmos.Encryption.Custom/tests/Microsoft.Azure.Cosmos.Encryption.Custom.Tests/MdeEncryptionProcessorTests.cs

@@ -230,11 +230,12 @@ private static async Task<JObject> VerifyEncryptionSucceeded(TestDoc testDoc, En
 
             Assert.IsNotNull(encryptionProperties);
             Assert.AreEqual(dekId, encryptionProperties.DataEncryptionKeyId);
-#if ENCRYPTION_CUSTOM_PREVIEW
-            Assert.AreEqual(4, encryptionProperties.EncryptionFormatVersion);
-#else
-            Assert.AreEqual(3, encryptionProperties.EncryptionFormatVersion);
-#endif
+
+            int expectedVersion = 
+                (encryptionOptions.CompressionOptions.Algorithm != CompressionOptions.CompressionAlgorithm.None)
+                ? 4 : 3;
+            Assert.AreEqual(expectedVersion, encryptionProperties.EncryptionFormatVersion);
+
             Assert.IsNull(encryptionProperties.EncryptedData);
             Assert.IsNotNull(encryptionProperties.EncryptedPaths);
 

Microsoft.Azure.Cosmos.Encryption.Custom/tests/Microsoft.Azure.Cosmos.Encryption.Custom.Tests/Transformation/BrotliCompressionTests.cs

@@ -1,6 +1,6 @@
 namespace Microsoft.Azure.Cosmos.Encryption.Tests.Transformation
 {
-#if ENCRYPTION_CUSTOM_PREVIEW && NET8_0_OR_GREATER
+#if NET8_0_OR_GREATER
     using System;
     using System.Collections.Generic;
     using System.IO.Compression;
@@ -44,7 +44,7 @@ public void GetQuality_ThrowsForUnknownLevels()
         public void CompressAndDecompress_HasSameResult(CompressionLevel compressionLevel, int payloadSize)
         {
             BrotliCompressor compressor = new (compressionLevel);
-            EncryptionProperties properties = new (0, "", "", null, null, CompressionOptions.CompressionAlgorithm.Brotli, new Dictionary<string, int>());
+            Dictionary<string, int> properties = new ();
             string path = "somePath";
 
             byte[] bytes = new byte[payloadSize];
@@ -59,9 +59,9 @@ public void CompressAndDecompress_HasSameResult(CompressionLevel compressionLeve
 
             Console.WriteLine($"Original: {bytes.Length} Compressed: {compressedBytesSize}");
 
-            Assert.IsTrue(properties.CompressedEncryptedPaths.ContainsKey(path));
+            Assert.IsTrue(properties.ContainsKey(path));
 
-            int recordedSize = properties.CompressedEncryptedPaths["somePath"];
+            int recordedSize = properties["somePath"];
             Assert.AreEqual(bytes.Length, recordedSize);
 
             byte[] decompressedBytes = new byte[recordedSize];