Add AbpBsonSerializer utility class

framework/src/Volo.Abp.MongoDB/Volo/Abp/MongoDB/AbpBsonSerializer.cs

@@ -0,0 +1,31 @@
+using System;
+using System.Collections.Concurrent;
+
+using System.Reflection;
+using MongoDB.Bson.Serialization;
+
+namespace Volo.Abp.MongoDB;
+
+public static class AbpBsonSerializer
+{
+    private static readonly ConcurrentDictionary<Type, IBsonSerializer> Cache;
+
+    static AbpBsonSerializer()
+    {
+        var registry = BsonSerializer.SerializerRegistry;
+        var type = typeof(BsonSerializerRegistry);
+        var cacheField = type.GetField("_cache", BindingFlags.NonPublic | BindingFlags.Instance) ??
+                         throw new AbpException($"Cannot find _cache field of {type.FullName}.");
+        Cache = (ConcurrentDictionary<Type, IBsonSerializer>)cacheField.GetValue(registry)!;
+    }
+
+    public static void RemoveSerializer<T>()
+    {
+        Cache.TryRemove(typeof(T), out _);
+    }
+
+    public static ConcurrentDictionary<Type, IBsonSerializer> GetSerializerCache()
+    {
+        return Cache;
+    }
+}