APIFactory.java

// Custom datetime serializer
private static final LocalDateTimeSerializer CUSTOM_DATE_SERIALIZER =
  new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("dd-MMM-yyyy HH:mm"));

// Custom datetime deserializer
private static final LocalDateTimeDeserializer CUSTOM_DATE_DESERIALIZER =
  new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern("dd-MMM-yyyy HH:mm"));
  
// Feign based API
public static FileApi getFileAPI() {
  String URL = "http://localhost:8080"; // This must be passed as an ENV variable
  return Feign.builder()
      .encoder(new JacksonEncoder(apiObjectMapper()))
      .decoder(new JacksonDecoder(apiObjectMapper()))
      .contract(new SpringMvcContract())
      .target(FileApi.class, URL);
}

// Default object mapper for JacksonEncoder
private static ObjectMapper apiObjectMapper() {
  ObjectMapper mapper = new ObjectMapper();
  mapper.registerModule(getTimeModule());
  return mapper;
}

// A custom module that registers datetime serializers/deserializers
public static Module getTimeModule() {
  JavaTimeModule timeModule = new JavaTimeModule();
  timeModule.addSerializer(CUSTOM_DATE_SERIALIZER);
  timeModule.addDeserializer(LocalDateTime.class, CUSTOM_DATE_DESERIALIZER);
  return timeModule;
}