Generate Schema for getters without corresponding fields

[nickkhine]

Hi is there anyway that I can generate the schema for getters that have no corresponding field easily? Tried a couple of the Options but having trouble to get this to work.

So for example if I have the class:

public class TestGetter {
    private String fieldThatWillGenerate;

    public TestGetter() {
    }

    public String getFieldThatWillNotGenerate() {
        return "";
    }

    public String getFieldThatWillGenerate() {
        return this.fieldThatWillGenerate;
    }
}

and the code

    @Test
    public void testGetterGeneration()
        throws JsonProcessingException {
        final ObjectMapper mapper = new ObjectMapper();
        final JacksonModule module = new JacksonModule();
        final SchemaGeneratorConfigBuilder configBuilder = new SchemaGeneratorConfigBuilder(mapper,
            SchemaVersion.DRAFT_2020_12,OptionPreset.PLAIN_JSON)
            .with(module);
        final SchemaGeneratorConfig config = configBuilder.build();
        final SchemaGenerator generator = new SchemaGenerator(config);
        final String actualJson = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(generator.generateSchema(TestGetter.class));
        System.out.println(actualJson);
    }

then the output would be

{
  "$schema" : "https://json-schema.org/draft/2020-12/schema",
  "type" : "object",
  "properties" : {
    "fieldThatWillGenerate" : {
      "type" : "string"
    }
  }
}

but I would like it to be

{
  "$schema" : "https://json-schema.org/draft/2020-12/schema",
  "type" : "object",
  "properties" : {
    "fieldThatWillGenerate" : {
      "type" : "string"
    },
    "fieldThatWillNotGenerate" : {
      "type" : "string"
    }
  }
}

so that it includes the suffix of the getter as the fieldname or the name using @JsonProperty if it is provided

[CarstenWickner]

HI @nickkhine,

I suggest you have a look at the documentation:
https://victools.github.io/jsonschema-generator/#generator-options

Since you're using the OptionPreset.PLAIN_JSON, you're missing the Option.NONSTATIC_NONVOID_NONGETTER_METHODS by default, which you should add explicitly in order for the getFieldThatWillNotGenerate() method to be considered.

Regarding the naming, Option.FIELDS_DERIVED_FROM_ARGUMENTFREE_METHODS would take care of your example.
The JacksonModule would use the @JsonProperty annotation's value instead if it is present.

However, this may include methods you don't want to be reflected in your JSON Schema (such as toString()).
Therefore you could either use the JacksonOption.INCLUDE_ONLY_JSONPROPERTY_ANNOTATED_METHODS on the JacksonModule and explicitly annotate each of the desired methods with @JsonProperty or you write your own configuration to ignore methods you don't want as per:
https://victools.github.io/jsonschema-generator/#omitting-ignoring-certain-fields-methods
e.g.

configBuilder.forMethods()
    .withIgnoreCheck(method -> !method.getDeclaredName().startsWith("get"));

[nickkhine]

Ah yes, this combination seems to work. Thanks for the quick response!