Add JsonNode BSON serializer (#6043)

Introduce JsonNodeBsonConverter for BSON serialization of JsonNode objects. Update MongoDbFeature to register the new serializer, enhancing JSON handling within MongoDB serialization context.

src/modules/Elsa.MongoDb/Features/MongoDbFeature.cs

@@ -1,4 +1,5 @@
 using System.Text.Json;
+using System.Text.Json.Nodes;
 using Elsa.Features.Abstractions;
 using Elsa.Features.Services;
 using Elsa.KeyValues.Entities;
@@ -8,6 +9,7 @@ using Elsa.MongoDb.Options;
 using Elsa.MongoDb.Serializers;
 using Elsa.Workflows.Memory;
 using Elsa.Workflows.Runtime.Entities;
+using Elsa.Workflows.Services;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
 using Microsoft.Extensions.Options;
@@ -67,6 +69,7 @@ public class MongoDbFeature : FeatureBase
         TryRegisterSerializerOrSkipWhenExist(typeof(Variable), new VariableSerializer());
         TryRegisterSerializerOrSkipWhenExist(typeof(Version), new VersionSerializer());
         TryRegisterSerializerOrSkipWhenExist(typeof(JsonElement), new JsonElementSerializer());
+        TryRegisterSerializerOrSkipWhenExist(typeof(JsonNode), new JsonNodeBsonConverter());
     }
 
     private static void RegisterClassMaps()

src/modules/Elsa.MongoDb/Serializers/JsonNodeBsonSerializer.cs

@@ -0,0 +1,135 @@
+using System.Text.Json.Nodes;
+using MongoDB.Bson;
+using MongoDB.Bson.IO;
+using MongoDB.Bson.Serialization;
+
+namespace Elsa.MongoDb.Serializers;
+
+/// <summary>
+/// Serializes a <see cref="JsonNode"/>.
+/// </summary>
+public class JsonNodeBsonConverter : IBsonSerializer<JsonNode>
+{
+    /// <inheritdoc />
+    public Type ValueType => typeof(JsonNode);
+
+    /// <inheritdoc />
+    public void Serialize(BsonSerializationContext context, BsonSerializationArgs args, JsonNode value)
+    {
+        if (value == null!)
+        {
+            context.Writer.WriteNull();
+            return;
+        }
+
+        context.Writer.WriteStartDocument();
+        context.Writer.WriteName("type");
+
+        switch (value)
+        {
+            case JsonObject jsonObject:
+                context.Writer.WriteString("JsonObject");
+                context.Writer.WriteName("value");
+                context.Writer.WriteString(jsonObject.ToJsonString());
+                break;
+
+            case JsonArray jsonArray:
+                context.Writer.WriteString("JsonArray");
+                context.Writer.WriteName("value");
+                context.Writer.WriteString(jsonArray.ToJsonString());
+                break;
+
+            case JsonValue jsonValue:
+                context.Writer.WriteString("JsonValue");
+                context.Writer.WriteName("value");
+                if (jsonValue.TryGetValue(out string? stringValue))
+                    context.Writer.WriteString(stringValue);
+                else if (jsonValue.TryGetValue(out int intValue))
+                    context.Writer.WriteInt32(intValue);
+                else if (jsonValue.TryGetValue(out int longValue))
+                    context.Writer.WriteInt64(longValue);
+                else if (jsonValue.TryGetValue(out double doubleValue))
+                    context.Writer.WriteDouble(doubleValue);
+                else if (jsonValue.TryGetValue(out bool boolValue))
+                    context.Writer.WriteBoolean(boolValue);
+                else if (jsonValue.TryGetValue(out DateTimeOffset dateTimeOffsetValue))
+                    context.Writer.WriteDateTime(dateTimeOffsetValue.ToUnixTimeMilliseconds());
+                else if (jsonValue.TryGetValue(out DateTime dateTimeValue))
+                    context.Writer.WriteDateTime(new DateTimeOffset(dateTimeValue).ToUnixTimeMilliseconds());
+                else
+                    throw new BsonSerializationException("Unsupported JsonValue type");
+                break;
+
+            default:
+                throw new BsonSerializationException($"Unexpected JsonNode type: {value.GetType()}");
+        }
+
+        context.Writer.WriteEndDocument();
+    }
+
+    public JsonNode Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
+    {
+        context.Reader.ReadStartDocument();
+        var type = context.Reader.ReadString();
+        context.Reader.ReadName(Utf8NameDecoder.Instance);
+
+        JsonNode result;
+        switch (type)
+        {
+            case "JsonObject":
+                var jsonObjectString = context.Reader.ReadString();
+                result = JsonNode.Parse(jsonObjectString);
+                break;
+
+            case "JsonArray":
+                var jsonArrayString = context.Reader.ReadString();
+                result = JsonNode.Parse(jsonArrayString);
+                break;
+
+            case "JsonValue":
+                var bsonType = context.Reader.GetCurrentBsonType();
+                switch (bsonType)
+                {
+                    case BsonType.String:
+                        result = JsonValue.Create(context.Reader.ReadString());
+                        break;
+                    case BsonType.Int32:
+                        result = JsonValue.Create(context.Reader.ReadInt32());
+                        break;
+                    case BsonType.Int64:
+                        result = JsonValue.Create(context.Reader.ReadInt64());
+                        break;
+                    case BsonType.Double:
+                        result = JsonValue.Create(context.Reader.ReadDouble());
+                        break;
+                    case BsonType.Boolean:
+                        result = JsonValue.Create(context.Reader.ReadBoolean());
+                        break;
+                    case BsonType.DateTime:
+                        result = JsonValue.Create(context.Reader.ReadDateTime());
+                        break;
+                    default:
+                        throw new BsonSerializationException($"Unsupported BSON type: {bsonType}");
+                }
+                break;
+
+            default:
+                throw new BsonSerializationException($"Unsupported JsonNode type: {type}");
+        }
+
+        context.Reader.ReadEndDocument();
+        return result!;
+    }
+
+    /// <inheritdoc />
+    public void Serialize(BsonSerializationContext context, BsonSerializationArgs args, object value)
+    {
+        Serialize(context, args, (JsonNode)value);
+    }
+
+    object IBsonSerializer.Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
+    {
+        return Deserialize(context, args);
+    }
+}
+