How to configure custom BsonTypeClassMap

[XSpielinbox]

Unfortunately, MongoDB by default decodes BSON DateTime to java.util.Date, not java.time.LocalDateTime, which causes all sorts of errors in our application.

To circumvent this, we have the following class in our code base:

@Configuration
public class MongoConfig {

    @Bean
    public MongoClientSettingsBuilderCustomizer mongoClientSettingsBuilderCustomizer() {
        BsonTypeClassMap classMap = new BsonTypeClassMap(Map.of(BsonType.DATE_TIME, LocalDateTime.class));
        return builder -> builder.codecRegistry(CodecRegistries.fromRegistries(
                CodecRegistries.fromProviders(new DocumentCodecProvider(classMap)),
                MongoClientSettings.getDefaultCodecRegistry(),
                CodecRegistries.fromProviders(PojoCodecProvider.builder().automatic(true).build())
        ));
    }
}

However, in the test classes, this does not get called and we still have these issues. We could not find a way how to configure this in Embedded Mongo directly or how to hand over custom MongoClientSettings. Unfortunately, when the ReactiveClientAdapter creates the MongoClient it sets the MongoClientSettings to the defaults which cannot be changed after the construction of the client.

We are using Spring Boot 3.3.3 with de.flapdoodle.embed.mongo version 4.17.0 and de.flapdoodle.embed.mongo.spring3x version 4.16.1 with Java 21.

How can we configure Embedded Mongo to not use the obsolete java.util.Date?

If you need any further information, please let me know.

Thank you for your great work and help!

[michaelmosmann]

@XSpielinbox i will have a look at this..