Camel exchange header lost during test - apache-camel

Question

I'm trying to test the onException(JsonProcessingException.class) route in the following class (please don't mind its name, I've cut some code out for clarity):
import org.apache.camel.Exchange;
import org.apache.camel.LoggingLevel;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.model.rest.RestBindingMode;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import com.fasterxml.jackson.core.JsonProcessingException;
import pl.muni.camel.sample.customer.domain.CustomerData;
import pl.muni.camel.sample.customer.route.processor.CreateCustomerErrorResponseProcessor;
import pl.muni.camel.sample.customer.route.processor.CreateCustomerOkResponseProcessor;
#Component
public class SendCustomerDataToQueueRoute extends RouteBuilder {
#Value("${http.rest.listener.host}")
private String restListenerHost;
#Value("${http.rest.listener.port}")
private int restListenerPort;
#Override
public void configure() {
restConfiguration()
.component("restlet")
.dataFormatProperty("prettyPrint", "true")
.host(restListenerHost)
.port(restListenerPort);
rest("/rest/v1/customer")
.post("/create")
.bindingMode(RestBindingMode.json)
.skipBindingOnErrorCode(false)
.consumes("application/json")
.type(CustomerData.class)
.produces("application/json")
.route().id("acceptCreateCustomerRequest")
.from("direct:acceptRequest")
.to("direct:processRequest");
onException(JsonProcessingException.class)
.handled(true)
.setHeader(Exchange.HTTP_RESPONSE_CODE, constant(400))
.to("direct:processException");
onException(Exception.class)
.handled(true)
.setHeader(Exchange.HTTP_RESPONSE_CODE, constant(500))
.to("direct:processException");
from("direct:processRequest").routeId("processCreateCustomerRequest")
.log("Received customer data: ${body}")
.process(new CreateCustomerOkResponseProcessor()).id("createOkResponse");
from("direct:processException").routeId("processCreateCustomerException")
.log(LoggingLevel.ERROR, "${exception.stacktrace}").id("logExceptionStackTrace")
.process(new CreateCustomerErrorResponseProcessor()).id("createErrorResponse");
}
}
I want to intercept the exchange after createErrorResponse processor and run some assertions on it. So far I've come up with this code, in which I weave in a mock endpoint after direct:processException endpoint:
import java.util.List;
import org.apache.camel.CamelContext;
import org.apache.camel.EndpointInject;
import org.apache.camel.Exchange;
import org.apache.camel.Produce;
import org.apache.camel.ProducerTemplate;
import org.apache.camel.builder.AdviceWithRouteBuilder;
import org.apache.camel.component.mock.MockEndpoint;
import org.apache.camel.test.spring.CamelSpringBootRunner;
import org.apache.camel.test.spring.EnableRouteCoverage;
import org.apache.camel.test.spring.MockEndpointsAndSkip;
import org.apache.camel.test.spring.UseAdviceWith;
import org.assertj.core.api.Assertions;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.test.annotation.DirtiesContext;
import pl.muni.camel.sample.customer.infrastructure.rest.CreateCustomerResponse;
#UseAdviceWith
#MockEndpointsAndSkip("restlet*")
#EnableRouteCoverage
#DirtiesContext(classMode = DirtiesContext.ClassMode.AFTER_EACH_TEST_METHOD)
#SpringBootTest
#ComponentScan("pl.muni.camel.sample.customer")
#RunWith(CamelSpringBootRunner.class)
public class SendCustomerDataToQueueIntegrationTest {
#Produce
private ProducerTemplate producerTemplate;
#Autowired
private CamelContext context;
#EndpointInject(uri = "mock:error")
private MockEndpoint errorEndpoint;
#Before
public void setUp() throws Exception {
context.getRouteDefinition("processCreateCustomerRequest").adviceWith(context, new AdviceWithRouteBuilder() {
#Override
public void configure() {
weaveByToUri("direct:processException")
.after()
.to("mock:error");
}
});
context.start();
}
#After
public void tearDown() throws Exception {
context.stop();
}
#Test
public void shouldReturnHttpStatus400ForInvalidJson() throws InterruptedException {
// given
final String customerDataString = "{\"firstName\": \"aaa\", \"lastname\": \"bbb\"}";
//when
producerTemplate.sendBody("direct:acceptRequest", customerDataString);
//then
errorEndpoint.expectedHeaderReceived(Exchange.HTTP_RESPONSE_CODE, 400);
errorEndpoint.assertIsSatisfied();
final List<Exchange> exchanges = errorEndpoint.getExchanges();
Assertions.assertThat(exchanges).hasSize(1);
final Exchange exchange = exchanges.get(0);
final CreateCustomerResponse response = exchange.getIn().getBody(CreateCustomerResponse.class);
Assertions.assertThat(response.isSuccess()).isFalse();
Assertions.assertThat(response.getErrorMessage()).startsWith("UnrecognizedPropertyException: Unrecognized field \"lastname\"");
}
}
Unfortunately, the Exchange.HTTP_RESPONSE_CODE header somehow disappears during the test and the assertion on errorEndpoint fails. I ran the test with debugger and breakpoint set within CreateCustomerErrorResponseProcessor class and there the header was still available.
Is there another way to set up the test and be able to retrieve the header or could this be a bug?

Answer 1

The URI you are weaving ("direct:processException") in your unit test is attached to a wrong route definition.
It should be:
context.getRouteDefinition("processCreateCustomerException").adviceWith(...)
(and not "processCreateCustomerRequest")