MartenDB serializer issue

Question

Recently moved to latest version of MartenDB 6.4.0 and have started seeing the below error when attempting to query the postgres database for a list of stream events

Code await _querySession.Events.AggregateStreamAsync<TAggregate>(id, token: cancellationToken)

System.InvalidCastException: Reading as 'System.Collections.Generic.Dictionary`2[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[System.Object, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]]' is not supported for fields having DataTypeName 'jsonb'
 ---> System.NotSupportedException: Type 'Dictionary`2' required dynamic JSON serialization, which requires an explicit opt-in; call 'EnableDynamicJson' on 'NpgsqlDataSourceBuilder' or NpgsqlConnection.GlobalTypeMapper (see https://www.npgsql.org/doc/types/json.html and the 8.0 release notes for more details). Alternatively, if you meant to use Newtonsoft JSON.NET instead of System.Text.Json, call UseJsonNet() instead.

Example mt_events table payload

seq_id	id	stream_id	data
10.	018d1b4e-e410-4071-a201-f8a796523c01	69a2d0c6-64ff-4b71-b850-c23014a5bc7f	{"Id":123")

Martin config

options.Events.MetadataConfig.HeadersEnabled = true;
                options.Events.MetadataConfig.CausationIdEnabled = true;
                options.Events.MetadataConfig.CorrelationIdEnabled = true;
                options.UseDefaultSerialization(EnumStorage.AsString,
                    nonPublicMembersStorage: NonPublicMembersStorage.All);

Have tried altering the serializer and also downgrading Martin version with no luck

Answer 1

As per the error message you are getting JSON serialization, which requires an explicit opt-in; call 'EnableDynamicJson' , you now need to explicitly opt into Dynamic Json.

This worked for me by adding this line.

NpgsqlConnection.GlobalTypeMapper.EnableDynamicJson();

See official release notes documentation on NPGSQL:

JSON POCO and other dynamic features now require an explicit opt-in