Testing Integrations

Testing Integrations

Use GeneratorConfig as the root test configuration, then create short-lived generators inside test fixtures. This keeps locale, seed, object depth, and registry choices easy to audit.

JUnit fixtures

For per-test seed management with automatic failure-seed reporting, use the dedicated krandom-junit extension — see the JUnit Extension guide. The manual pattern below remains the right fit when one shared config drives many fixtures:

GeneratorConfig cfg = GeneratorConfig.builder()
        .locale(Locale.US)
        .seed(20260424L)
        .build();

Field field = Generators.ofField(cfg);
Map<String, SchemaValueProvider> fields = new LinkedHashMap<>();
fields.put("id", field.bind("code.uuid"));
fields.put("email", field.bind("person.email"));
fields.put("amount", field.bind("finance.money"));

Schema orders = Generators.ofSchema(cfg, fields);
Map<String, Object> row = orders.generate();

assert row.get("email").toString().contains("@");

Spring-style fixture factory

final class TestFixtureFactory {

    private final GeneratorConfig config;

    TestFixtureFactory(Locale locale, long seed) {
        this.config = GeneratorConfig.builder()
                .locale(locale)
                .seed(seed)
                .build();
    }

    OrderDto order() {
        return Generators.ofObject(OrderDto.class, config).generate();
    }

    PaymentInfo payment() {
        return Generators.ofPaymentInfo(config).generate();
    }
}

Create one factory per test class or test method if deterministic sequence isolation matters. Do not share one mutable generator instance across parallel tests.

JSON fixtures

For file-style fixtures, generate rows through Schema and serialize with Jackson:

ObjectMapper mapper = KrandomJackson.newObjectMapper();

Field field = Generators.ofField(Locale.US);
Schema schema = Generators.ofSchema(Locale.US, Map.of(
        "order", field.bind("commerce.order_info"),
        "payment", field.bind("finance.payment_info")
));

String json = mapper.writeValueAsString(schema.generate());

KrandomJackson.newObjectMapper() also serializes Schema itself as JSON Schema, which is useful when tests need both data rows and a contract document.