Checking Json Request Schema

Question

So, I have this controller class that contains this method:

    @RequestMapping(value = "/x", method = RequestMethod.POST, produces = MediaType.APPLICATION_JSON_VALUE, consumes = MediaType.APPLICATION_JSON_VALUE)
    public ResponseEntity<MyRepsonseClass> get(
        @ApiParam(value = "x", required = true) @Valid @RequestBody MyRequestClass request
    ) throws IOException {
        //yada yada my logic here
        return something;
    }

Json request is automatically mapped to MyRequestClass.java

Here's what this class looks like:

@lombok.ToString
@lombok.Getter
@lombok.Setter
@JsonInclude(JsonInclude.Include.NON_EMPTY)
@ApiModel(description = "description")
public class MyRequestClass {
    private List<SomeClass> attribute1;
    private SomeOtherClass attribute2;
    private YetAnotherClass attribute3;
}

This is an example of a valid json request:

{
    "attribute1": [
        {
            "key":"value"
        }
    ],
    "attribute3": {
        "key":"value"
    }
}

Now my requirement is to return an error message when the request contains an attribute that does not exist in MyRequestClass.java.

In this way:

{
    "attribute1": [
        {
            "key":"value"
        }
    ],
    "attribute_that_doesnt_exist": {
        "key":"value"
    }
}

Now he is not throwing any mistakes. Rather, it simply does not match this attribute with anything. Are there any annotations I can use so that this can happen quickly? Thank.

Answer 1

Create your own deserializer:

public class MyRequestClassDeserializer extends JsonDeserializer<MyRequestClass> {
    @Override
    public MyRequestClass deserialize(JsonParser jsonParser, DeserializationContext context) throws IOException, JsonProcessingException {
        MyRequestClass mrc = new MyRequestClass();
        ObjectMapper mapper = new ObjectMapper();
        JsonToken currentToken = null;
        while((currentToken = jsonParser.nextValue()) != null) {
            if(currentToken.equals(JsonToken.END_OBJECT) 
                    || currentToken.equals(JsonToken.END_ARRAY))
                continue;
            String currentName = jsonParser.getCurrentName();
            switch(currentName) {
                case "attribute1":
                    List<SomeClass> attr1 = Arrays.asList(mapper.readValue(jsonParser, SomeClass[].class));
                    mrc.setAttribute1(attr1);
                    break;
                case "attribute2":
                    mrc.setAttribute2(mapper.readValue(jsonParser, SomeOtherClass.class));
                    break;
                case "attribute3":
                    mrc.setAttribute3(mapper.readValue(jsonParser, YetAnotherClass.class));
                    break;
                // <cases for all the other expected attributes>
                default:// it not an expected attribute
                    throw new JsonParseException(jsonParser, "bad request", jsonParser.getCurrentLocation());
            }
        }
        return mrc;
    }
}  

MyRequestClass: @JsonDeserialize(using=MyRequestClassDeserializer.class)

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Answer 2

@JsonIgnoreProperties(ignoreUnknown = false)

Spring , , application.properties(yaml)

spring.jackson.deserialization.fail-on-unknown-properties=true