Spring Cloud app - zuul timeout after deploying on Tomcat - spring-cloud

Question

I'm trying to set up a couple of services using Spring Cloud and everything seems to work fine up until the moment I deploy the Eureka client services to Tomcat. When I call a service through my gateway app, I get the following error:
o.s.c.n.z.filters.post.SendErrorFilter : Error during filtering
com.netflix.zuul.exception.ZuulException: Forwarding error
...
Caused by: com.netflix.hystrix.exception.HystrixRuntimeException: hello timed-out and no fallback available.
...
Caused by: java.util.concurrent.TimeoutException: null
It works perfectly from eclipse however. It even works when I run the discovery and gateway services from Tomcat, and run the Eureka client service from eclipse. But as soon as I run the same service on tomcat, I get the error.
I'm using Brixton.M5, Java 8 and Tomcat 8.
Again, the code seems to work, the problem is it doesn't work after being deployed to Tomcat.
I have one Tomcat instance for the Discovery and Gateway services, and a second Tomcat instance for the Eureka client services.
Here's some code and config..
DiscoveryServerApp
#SpringBootApplication
#EnableEurekaServer
public class DiscoveryServerApp extends SpringBootServletInitializer
{
public static void main(String[] args)
{
SpringApplication.run(DiscoveryServerApp.class, args);
}
}
DiscoveryServer - application.yml
# Configure this Discovery Server
eureka:
instance:
hostname: discovery
client: # Not a client, don't register with yourself
registerWithEureka: false
fetchRegistry: false
serviceUrl:
defaultZone: http://localhost:1111/discovery/eureka/
server:
port: 1111 # HTTP (Tomcat) port
context-path: /discovery
DiscoveryServer - bootstrap.yml
spring:
application:
name: discovery
jmx:
default-domain: com.example.cloud.discovery
GatewayApplication
#SpringCloudApplication
#EnableZuulProxy
public class GatewayApplication extends SpringBootServletInitializer
{
public static void main(String[] args)
{
SpringApplication.run(GatewayApplication.class, args);
}
}
GatewayApplication - application.yml
# Discovery Server Access
eureka:
client:
serviceUrl:
defaultZone: http://localhost:1111/discovery/eureka/
instance:
instanceId: ${spring.application.name}:${spring.application.instance_id:${random.value}}
# HTTP Server
server:
port: 4444 # HTTP (Tomcat) port
context-path: /api
GatewayApplication - bootstrap.yml
# Spring properties
spring:
application:
name: gateway-service # Identify this application
jmx:
default-domain: com.example.cloud.gateway
encrypt:
failOnError: false
DummyApplication
#SpringCloudApplication
#RestController
public class DummyApplication extends SpringBootServletInitializer
{
public static void main(String[] args)
{
SpringApplication.run(DummyApplication.class, args);
}
#RequestMapping( path = "/hello-resource", method = RequestMethod.GET )
public String hello()
{
return "hello";
}
}
DummyApplication - application.yml
# Discovery Server Access
eureka:
client:
serviceUrl:
defaultZone: http://localhost:1111/discovery/eureka/
instance:
instanceId: ${spring.application.name}:${spring.application.instance_id:${random.value}} # Unique id for multiple instances
# HTTP Server
server:
port: 3333 # HTTP (Tomcat) port
context-path: /hello-context
DummyApplication - bootstrap.yml
# Spring properties
spring:
application:
name: hello-service # Service registers under this name
jmx:
default-domain: com.example.cloud.hello
encrypt:
failOnError: false

Answer 1

I figured it out by accident... turns out that the value of server.port needs to match the port of the Tomcat instance where it's deployed. It seems obvious now, but I thought Spring would somehow magically figure that out from the container it's running in. I guess it would be a good idea to read that configuration from an external location to handle different environments without having to make 'code changes'.
So anyways, the answer is: make sure your server.port in application.yml matches the port on the target container.
Thanks to everyone who took the time to help me with this!

Answer 2

You should point your bowser to port 4444 (gateway), not 1111 (eureka).

Answer 3

Ok, #SpringCloudApplication wraps #EnableDiscoveryClient which causes DummyApplication to register itself with Eureka on startup. You can confirm this is happening through the Eureka dashboard.
Assuming DummyApplication registers with Eureka as service name "hello-service", then Zuul / Ribbon will create a route for that service name. Thus, your "/hello-resource" endpoint should be proxied through Zuul at:
http://localhost:4444/api/hello-service/hello-resource/