Use Source Generation for json (de)serialization

src/Common.Tests/NodeBuildResultTests.cs

@@ -52,8 +52,8 @@ public void SortWorksConsistentlyAcrossJson()
                 null
             );
 
-            string serialized = JsonSerializer.Serialize(nodeBuildResult);
-            NodeBuildResult deserialized = JsonSerializer.Deserialize<NodeBuildResult>(serialized)!;
+            string serialized = JsonSerializer.Serialize(nodeBuildResult, SourceGenerationContext.Default.NodeBuildResult);
+            NodeBuildResult deserialized = JsonSerializer.Deserialize(serialized, SourceGenerationContext.Default.NodeBuildResult)!;
 
             CollectionAssert.AreEqual(expected.Keys, deserialized.Outputs.Keys, "\n" +
                 "Permutation: " + string.Join(", ", permutation) + "\n" +

src/Common/Caching/CacheClient.cs

@@ -5,6 +5,8 @@
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.IO;
+using System.Text.Json;
+using System.Text.Json.Serialization.Metadata;
 using System.Threading;
 using System.Threading.Tasks;
 using BuildXL.Cache.ContentStore.Hashing;
@@ -21,7 +23,6 @@
 using Microsoft.CopyOnWrite;
 using Microsoft.MSBuildCache.Fingerprinting;
 using Microsoft.MSBuildCache.Hashing;
-using JsonSerializer = System.Text.Json.JsonSerializer;
 using Fingerprint = Microsoft.MSBuildCache.Fingerprinting.Fingerprint;
 using WeakFingerprint = BuildXL.Cache.MemoizationStore.Interfaces.Sessions.Fingerprint;
 
@@ -276,7 +277,7 @@ public async Task AddNodeInternalAsync(
         Context context = new(RootContext);
 
         // compute the metadata content.
-        byte[] nodeBuildResultBytes = await SerializeAsync(nodeBuildResult, cancellationToken);
+        byte[] nodeBuildResultBytes = await SerializeAsync(nodeBuildResult, SourceGenerationContext.Default.NodeBuildResult, cancellationToken);
         ContentHash nodeBuildResultHash = _hasher.GetContentHash(nodeBuildResultBytes)!;
 
         Tracer.Debug(context, $"Computed node metadata {nodeBuildResultHash.ToShortString()} to the cache for {nodeContext.Id}");
@@ -286,7 +287,7 @@ public async Task AddNodeInternalAsync(
         if (pathSet != null)
         {
             // Add the PathSet to the ContentStore
-            byte[] pathSetByteArray = await SerializeAsync(pathSet, cancellationToken);
+            byte[] pathSetByteArray = await SerializeAsync(pathSet, SourceGenerationContext.Default.PathSet, cancellationToken);
             ContentHash pathSetBytesHash = _hasher.GetContentHash(pathSetByteArray)!;
 
             Tracer.Debug(context, $"Computed PathSet {pathSetBytesHash.ToShortString()} to the cache for {nodeContext.Id}");
@@ -402,7 +403,7 @@ await AddNodeAsync(
         }
 
         // The first file is special: it is a serialized NodeBuildResult file.
-        NodeBuildResult? nodeBuildResult = await DeserializeAsync<NodeBuildResult>(context, nodeBuildResultStream, cancellationToken);
+        NodeBuildResult? nodeBuildResult = await DeserializeAsync(context, nodeBuildResultStream, SourceGenerationContext.Default.NodeBuildResult, cancellationToken);
         if (nodeBuildResult is null)
         {
             Tracer.Debug(context, $"Failed to deserialize NodeBuildResult for {cacheStrongFingerprint}");
@@ -505,7 +506,7 @@ async Task PlaceFilesAsync(CancellationToken ct)
             ContentHash pathSetHash = selector.ContentHash;
             byte[]? selectorStrongFingerprint = selector.Output;
 
-            PathSet? pathSet = await FetchAndDeserializeFromCacheAsync<PathSet>(context, pathSetHash, cancellationToken);
+            PathSet? pathSet = await FetchAndDeserializeFromCacheAsync(context, pathSetHash, SourceGenerationContext.Default.PathSet, cancellationToken);
 
             if (pathSet is null)
             {
@@ -526,20 +527,20 @@ async Task PlaceFilesAsync(CancellationToken ct)
         return (null, null);
     }
 
-    private static async Task<byte[]> SerializeAsync<T>(T data, CancellationToken cancellationToken)
+    private static async Task<byte[]> SerializeAsync<T>(T data, JsonTypeInfo<T> typeInfo, CancellationToken cancellationToken)
         where T : class
     {
         using (var memoryStream = new MemoryStream())
         {
-            await JsonSerializer.SerializeAsync(memoryStream, data, SerializationHelper.SerializerOptions, cancellationToken);
+            await JsonSerializer.SerializeAsync(memoryStream, data, typeInfo, cancellationToken);
             return memoryStream.ToArray();
         }
     }
 
-    private async Task<T?> DeserializeAsync<T>(Context context, Stream stream, CancellationToken cancellationToken)
+    private async Task<T?> DeserializeAsync<T>(Context context, Stream stream, JsonTypeInfo<T> typeInfo, CancellationToken cancellationToken)
         where T : class
     {
-        T? data = await stream.DeserializeAsync<T>(SerializationHelper.SerializerOptions, cancellationToken);
+        T? data = await stream.DeserializeAsync(typeInfo, cancellationToken);
         if (data is null)
         {
             Tracer.Debug(context, $"Content deserialized as null");
@@ -548,7 +549,7 @@ private static async Task<byte[]> SerializeAsync<T>(T data, CancellationToken ca
         return data;
     }
 
-    protected async Task<T?> FetchAndDeserializeFromCacheAsync<T>(Context context, ContentHash contentHash, CancellationToken cancellationToken)
+    protected async Task<T?> FetchAndDeserializeFromCacheAsync<T>(Context context, ContentHash contentHash, JsonTypeInfo<T> typeInfo, CancellationToken cancellationToken)
     where T : class
     {
         context = new(context);
@@ -562,7 +563,7 @@ private static async Task<byte[]> SerializeAsync<T>(T data, CancellationToken ca
 
         using (streamResult.Stream)
         {
-            return await DeserializeAsync<T>(context, streamResult.Stream!, cancellationToken);
+            return await DeserializeAsync(context, streamResult.Stream!, typeInfo, cancellationToken);
         }
     }
 

src/Common/MSBuildCachePluginBase.cs

@@ -882,7 +882,7 @@ private static async Task DumpBuildResultLogAsync(
         try
         {
             using FileStream fileStream = File.Create(filePath);
-            await JsonSerializer.SerializeAsync(fileStream, nodeBuildResult, SerializationHelper.SerializerOptions);
+            await JsonSerializer.SerializeAsync(fileStream, nodeBuildResult, SourceGenerationContext.Default.NodeBuildResult);
         }
         catch (Exception ex)
         {

src/Common/NodeBuildResult.cs

@@ -3,7 +3,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Text.Json;
 using System.Text.Json.Serialization;
 using BuildXL.Cache.ContentStore.Hashing;
 using Microsoft.Build.Execution;
@@ -34,7 +33,6 @@ public NodeBuildResult(
 
     // Use a sorted dictionary so the JSON output is deterministically sorted and easier to compare build-to-build.
     // These paths are repo-relative.
-    [JsonConverter(typeof(SortedDictionaryConverter))]
     public SortedDictionary<string, ContentHash> Outputs { get; }
 
     // Use a sorted dictionary so the JSON output is deterministically sorted and easier to compare build-to-build.
@@ -76,48 +74,4 @@ public CacheResult ToCacheResult(PathNormalizer pathNormalizer)
 
         return CacheResult.IndicateCacheHit(targetResults);
     }
-
-    private sealed class SortedDictionaryConverter : JsonConverter<SortedDictionary<string, ContentHash>>
-    {
-        public override SortedDictionary<string, ContentHash>? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
-        {
-            var contentHashConverter = (JsonConverter<ContentHash>)options.GetConverter(typeof(ContentHash));
-            var outputs = new SortedDictionary<string, ContentHash>(StringComparer.OrdinalIgnoreCase);
-            while (reader.Read())
-            {
-                if (reader.TokenType == JsonTokenType.EndObject)
-                {
-                    break;
-                }
-
-                if (reader.TokenType != JsonTokenType.PropertyName)
-                {
-                    throw new JsonException($"Unexpected token: {reader.TokenType}");
-                }
-
-                string propertyName = reader.GetString()!;
-                if (!reader.Read())
-                {
-                    throw new JsonException($"Property name '{propertyName}' does not have a value.");
-                }
-
-                ContentHash? contentHash = contentHashConverter.Read(ref reader, typeof(ContentHash), options);
-                if (contentHash == null)
-                {
-                    throw new JsonException($"Property value for '{propertyName}' could not be parsed.");
-                }
-
-                outputs.Add(propertyName, contentHash.Value);
-            }
-
-            return outputs;
-        }
-
-        public override void Write(Utf8JsonWriter writer, SortedDictionary<string, ContentHash> value, JsonSerializerOptions options)
-        {
-            var defaultConverter = (JsonConverter<SortedDictionary<string, ContentHash>>)
-                options.GetConverter(typeof(SortedDictionary<string, ContentHash>));
-            defaultConverter.Write(writer, value, options);
-        }
-    }
 }

src/Common/SerializationHelper.cs

@@ -1,27 +1,26 @@
 // Copyright (c) Microsoft. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+using System;
 using System.IO;
 using System.Text;
-using System.Threading.Tasks;
-using System.Threading;
-using System;
 using System.Text.Json;
+using System.Text.Json.Serialization.Metadata;
+using System.Threading;
+using System.Threading.Tasks;
 
 namespace Microsoft.MSBuildCache;
 
 internal static class SerializationHelper
 {
     public static JsonWriterOptions WriterOptions { get; } = new JsonWriterOptions { Indented = true };
 
-    public static JsonSerializerOptions SerializerOptions { get; } = CreateJsonSerializerOptions();
-
-    internal static async Task<T?> DeserializeAsync<T>(this Stream stream, JsonSerializerOptions? options = null, CancellationToken cancellationToken = default)
+    internal static async Task<T?> DeserializeAsync<T>(this Stream stream, JsonTypeInfo<T> typeInfo, CancellationToken cancellationToken = default)
         where T : class
     {
         try
         {
-            return await JsonSerializer.DeserializeAsync<T>(stream, options, cancellationToken);
+            return await JsonSerializer.DeserializeAsync(stream, typeInfo, cancellationToken);
         }
         catch (JsonException)
         {
@@ -56,14 +55,4 @@ internal static class SerializationHelper
             throw new InvalidOperationException(message);
         }
     }
-
-    private static JsonSerializerOptions CreateJsonSerializerOptions()
-    {
-        JsonSerializerOptions options = new()
-        {
-            WriteIndented = true,
-        };
-        options.Converters.Add(new ContentHashJsonConverter());
-        return options;
-    }
 }

src/Common/SortedDictionaryConverter.cs

@@ -0,0 +1,53 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using BuildXL.Cache.ContentStore.Hashing;
+using System.Collections.Generic;
+
+namespace Microsoft.MSBuildCache;
+
+internal sealed class SortedDictionaryConverter : JsonConverter<SortedDictionary<string, ContentHash>>
+{
+    public override SortedDictionary<string, ContentHash>? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+    {
+        var contentHashConverter = (JsonConverter<ContentHash>)options.GetConverter(typeof(ContentHash));
+        var outputs = new SortedDictionary<string, ContentHash>(StringComparer.OrdinalIgnoreCase);
+        while (reader.Read())
+        {
+            if (reader.TokenType == JsonTokenType.EndObject)
+            {
+                break;
+            }
+
+            if (reader.TokenType != JsonTokenType.PropertyName)
+            {
+                throw new JsonException($"Unexpected token: {reader.TokenType}");
+            }
+
+            string propertyName = reader.GetString()!;
+            if (!reader.Read())
+            {
+                throw new JsonException($"Property name '{propertyName}' does not have a value.");
+            }
+
+            ContentHash? contentHash = contentHashConverter.Read(ref reader, typeof(ContentHash), options);
+            if (contentHash == null)
+            {
+                throw new JsonException($"Property value for '{propertyName}' could not be parsed.");
+            }
+
+            outputs.Add(propertyName, contentHash.Value);
+        }
+
+        return outputs;
+    }
+
+    public override void Write(Utf8JsonWriter writer, SortedDictionary<string, ContentHash> value, JsonSerializerOptions options)
+    {
+        var defaultConverter = (JsonConverter<IDictionary<string, ContentHash>>)options.GetConverter(typeof(IDictionary<string, ContentHash>));
+        defaultConverter.Write(writer, value, options);
+    }
+}

src/Common/SourceGenerationContext.cs

@@ -0,0 +1,17 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.Collections.Generic;
+using System.Text.Json.Serialization;
+using BuildXL.Cache.ContentStore.Hashing;
+using Microsoft.MSBuildCache.Fingerprinting;
+
+namespace Microsoft.MSBuildCache;
+
+[JsonSourceGenerationOptions(WriteIndented = true, Converters = [typeof(ContentHashJsonConverter), typeof(SortedDictionaryConverter)])]
+[JsonSerializable(typeof(NodeBuildResult))]
+[JsonSerializable(typeof(PathSet))]
+[JsonSerializable(typeof(IDictionary<string, ContentHash>))]
+internal partial class SourceGenerationContext : JsonSerializerContext
+{
+}