Issue in routingFunction when passing Parent reference containing child object while routing to function

[Mohit-Sardiwal]

Describe the bug
Hi Team,

I am using RoutingFunction of the spring cloud.
(this is link to the sample code base -https://github.com/Mohit-Sardiwal/inheritance
which I am explaining below)

Lets say I have Parent class , Child class which extends Parent and GrandChild which extends Child class.
I am using parent reference and GrandChild object to store the below json string payload

 ObjectMapper objectMapper = new ObjectMapper();
Object jsonObject = objectMapper.readValue(jsonString, GrandChild.class);
Parent parent = (Parent)jsonObject ;

{
	"id": "4a001",
	"name": "John",
	"childId": "12345",
	"value": "first",
	"properties": {
		"hobbies": [
			{
				"hobbyId": "http",
				"hobbyName": "http"
			}
		]
	}
}

I am making list of the above Parent object and making spring message out of it and passing that message to routingFunction

List parentList = new ArrayList<>();
parentList.add(parent);

Message object = (Message) MessageBuilder.withPayload(parentList).build();

Message<T> functionMessage = MessageBuilder
.withPayload(object.getPayload())
.setHeader("spring.cloud.function.definition", "getFamilyData")
.setHeader(MessageHeaders.CONTENT_TYPE, "text/plain")
.copyHeadersIfAbsent(object.getHeaders())
.build();**

in my function (getFamilyData) I am expecting list of Child (as shown below). But I when I am using CONTENT_TYPE as text/plain I am getting empty list in FxGetFamilyData function and when I am not passing CONTENT_TYPE then I am getting list but in that I am only getting Child data . Grand Child data is not there.

**@Bean
  public Function<List<Child>, List<Child>> getFamilyData() {
    return new FxGetFamilyData();
  }**

**public class FxGetFamilyData implements UnaryOperator<List<Child>> {
  @Override
  public List<Child> apply(List<Child> children) {
    log.debug("Received Event :{}",children);
    return children;
  }
}

When ContentType is text/plain:
Received Event :[]

When ContentType is not send in headers (Not able to receive GrandChild data)
Received Event :[Child(childId=12345, value=first)]**

Classes

public class Parent {
  private String id;
  private String name;
}

public class Child extends Parent{
  private String childId;
  private String value;
}

public class GrandChild extends Child{
  private GrandChildProperties properties;
}

public class GrandChildProperties {
  private List<Hobbies> hobbies;
}

public class Hobbies {
  private String hobbyId;
  private String hobbyName;
}

[olegz]

Not passing any content type will default to application/json. Passing text/plain will not work here and should not work. I'd be surprised if it did. You are passing json and expect what in terms of text/plain?
In any case with application/json i get

[childId: 12345 value: first id: 4a001 name: John]

So I am not sure what doesn't work in your sample, but also it has nothing to do with RoutingFunction since it properly delegates to an appropriate function based on spring.cloud.function.definition header.

[olegz]

Closing it do to inactivity from the original reporter