Deserialize a DateTime from two sources in different formats

[elvis-gbmme]

Hi,
I have a built_value class that gets data from two sources (firestore and elasticsearch). The two formats are Firestore in DateTime and elastic in DateTime as String.

I'm already using the following serializers StandardJsonPlugin, TimestampSerializerPlugin (#541) and GeopointSerializerPlugin

The firesstore data is working fine after using the TimestampSerializer, but the elasticsearch sends the DateTime in a string format which causes the following exception
failed due to: Deserializing '2019-07-22T09:43:01.000Z' to 'DateTime' failed due to: type 'String' is not a subtype of type 'int' in type cast

I found #454 to be close to my issue and tried using it, but it breaks even my firestore serialization with the error Unhandled Exception: type '_TypeError' is not a subtype of type 'Exception'.

Kindly help.

Thanks.

[raulmabe]

I am currently dealing with this exact issue.
Deserializing '1998-04-02T05:35:55.000Z' to 'DateTime' failed due to: type 'String' is not a subtype of type 'int' in type cast)

I added this plugin to the serializer and now it works (I didn't achieved to serialize it with the same format it was deserialized, but still):

import 'package:built_value/serializer.dart';

class DateTimeSerializerPlugin implements SerializerPlugin {
  @override
  Object beforeSerialize(Object object, FullType specifiedType) {
    if (specifiedType.root != DateTime) return object;
    return DateTime.parse(object.toString()).toUtc();
  }

  @override
  Object afterSerialize(Object object, FullType specifiedType) => object;

  @override
  Object beforeDeserialize(Object object, FullType specifiedType) {
    if (specifiedType.root != DateTime) return object;
    return DateTime.parse(object as String).toUtc().microsecondsSinceEpoch;
  }

  @override
  Object afterDeserialize(Object object, FullType specifiedType) => object;
}

[davidmorgan]

This requires #1046