Spring Cloud Contract and Zuul - spring-cloud

Question

Using Spring Cloud Dalston, we have built a proxy service that, of course, uses Zuul. I am now trying to add Spring Cloud Contract tests to verify our proxy service works as expected from a contract adherence perspective. What is strange is that I can send a request and receive a 200 status code back, but the expected response body, content type header, etc. is empty, and my tests fail as a result.
Are there additional configurations not specified in the Spring Cloud Contract documentation necessary for testing services that use Zuul capabilities?

Answer 1

Here you have an example https://github.com/spring-cloud/spring-cloud-contract/issues/450
/**
* Abstraction of configuration to test contracts with external microservices which are using a zuul-gateway in between.
*
* When a provider of data only allows communication through a Zuul-Gateway, a special way to ensure valid contracts is needed.
* The Goal is to emulate the Zuul-Interception to be able to use the contracts stored within the providing service.
*
* F.e.: Consumer-Service consumes the Provider-Service, but the provider can not be called directly.
* The Consumer-Service calls an URL with a prefix consisting of the name of the gateway ("gateway") and name of the
* service (in this example "Provider-Service"). For example: http://gateway/provider/path/to/resource.
* The contract provided by Provider-Service holds only a part of the provided URL (here: "/path/to/resource").
* The resolution of "gateway" and "provider" is done within this class.
*/
#RunWith(SpringRunner.class)
#SpringBootTest(classes = EmbeddedZuulProxy.class,
properties = {"server.port: 8080",
"zuul.routes.provider.path: /provider/**",
"zuul.routes.provider.service-id: provider",
"zuul.routes.provider.url: http://localhost:9090/" //the url of the provider-stub is at port 9090
},
webEnvironment = WebEnvironment.DEFINED_PORT) //defined port is important! Ribbon points to zuul, which then points to the provider-stub
#AutoConfigureMockMvc
#AutoConfigureJsonTesters
//the stub runs on fixed port 9090, so that zuul can point to it
#AutoConfigureStubRunner(ids = "<group-id>:<artifact-id>:+:stubs:9090")
#DirtiesContext
public abstract class ZuulContractBase {
}
/**
* Configuration and Setup of an embedded Zuul-Gateway.
* This way it is possible to use contracts, stored in providing service
*/
#Configuration
#ComponentScan(basePackages = "<path.to.feign.client>") //autowiring feign client
#EnableAutoConfiguration
#EnableZuulProxy
#EnableFeignClients
#RibbonClient(name = "gateway", configuration = SimpleRibbonClientConfiguration.class)
class EmbeddedZuulProxy {
#Bean
RouteLocator routeLocator(DiscoveryClient discoveryClient,
ZuulProperties zuulProperties) {
return new DiscoveryClientRouteLocator("/", discoveryClient, zuulProperties);
}
}
/**
* Ribbon Load balancer with fixed server list for "simple" pointing to localhost,
* which holds the mocked zuul-gateway
*
* f.e. a call with feign would normally look like:
* http://gateway/provider/rest/path/to/your/{url}
* which is mapped to:
* http://localhost:{zuulport}/provider/rest/path/to/your/{url}
*/
#Configuration
class SimpleRibbonClientConfiguration {
#Value("${server.port}")
private Integer zuulPort;
#Bean
public ServerList<Server> ribbonServerList() {
return new StaticServerList<>(new Server("localhost", zuulPort));
}
}