ignoreNullMembers Annotation is ignored

[Lars-Sommer]

I have a DTLocation model with a DTGeoPosition object property which is null. I do not want this property to be serialized, I want to omit it. (Actually I want this to be the overall default setting for JsonMapper) This is my current state of the classes:

@JsonSerializable()
@Json(ignoreNullMembers: true)
class DTLocationRequest {
  String? Test;
  DTGeoPosition? GeoPosition;
}

@JsonSerializable()
@Json(ignoreNullMembers: true)
class DTGeoPosition {
  double lng = 0;
  double lat = 0;
  double accuracy = 0;
}

When I serialize a DTLocation class where DTGeoPosition is null: var json1 = JsonMapper.serialize(request); the null property is being serialized and is null: {"Test":"hello","GeoPosition":"null"}

If I serialize with options like this: var json2 = JsonMapper.serialize(request, SerializationOptions(ignoreNullMembers: true)); it works: {"Test":"hello"}

So it seems like the annotation is ignored, or am I missing something? As far as I can see, you cannot set default annotations like this, for all classes, is that correct?

[k-paxian]

As far as I can see, you cannot set default annotations like this, for all classes, is that correct?

yep, for global context you have SerializationOptions, for local context individual annotations.

I'll check this case and let you know what's wrong with it. Seems legit case for me

[k-paxian]

Well, here is a unit test which is covering this functionality. https://github.com/k-paxian/dart-json-mapper/blob/6d8da09ea7f034483fb00996d5a88fdeb7ee52a6/perf-test/test/unit/test.constructors.dart#L394 and it's green 💚 Highly probably you've not regenerated the code after altering @Json(ignoreNullMembers: true) annotation.

To force full regeneration cycle, you can:

• comment out any @JsonSerializable() annotation, switch your keyboard focus on the console running build runner
• wait till build runner finishes it's pass
• un-comment @JsonSerializable() annotation back and wait till build runner will succeeds

Usually to save on coding performance, code is not fully regenerated while you are typing. The only thing sensible is the presence/absence of @JsonSerializable() / @jsonSerializable annotation

[Lars-Sommer]

I´ve tried what you suggested, and it works. So the problem is that when you add annotation options, the builder doesn´t care about them until the @JsonSerializable() is removed from the class and added again? Anyways, thanks alot!

By the way, it would be nice if you could call initializeJsonMapper() with some default options, like ignoreNullMembers - but that is a detail. Thanks alot for an awesome project, it´s a great help!

[k-paxian]

Thanks for the suggestion, makes sense to me. I'll take it as improvement 😉

[Lars-Sommer]

Cool 🍻😊

[k-paxian]

@fasterlars Since 2.2.6+1 initializeJsonMapper() accepts global serialization/deserialization options. That's actually saved me a lot of redundant code in unit tests well done 👍 through the years I've not noticed such a straight forward move 😄

[Lars-Sommer]

Haha, awesome! 👍