We are in the process of standing up a new microservices architecture with Zuul at the front-end and a bunch of tomcat enabled microservices at the backend. Each service as it starts up, will register itself with Eureka and any client that wants to call those service will do so through Zuul. We've got this all wired in and everything is working fine.
However, I have a couple questions as to how we can make this architecture much more dynamic.
- One thing that we assumed was there out of the box with Ribbon/Eureka, but have yet to find a solution for is that as we add more services to the backend, that somehow (via Archiaus and update to Zuul's eureka-client.properties file) Zuul's Ribbon client would update itself with the new service details (e.g. vipaddress, load balancing algorithm, etc). So far, the only thing that works is to update the properties file and restart Zuul (ughhh).
For example, let's say today we have 2 microservices at the backend, therefore, Zuul's eureka/ribbon client configuration would include the below:
ribbon.client.niws.clientlist=service1|service2 zuul.ribbon.namespace=zuul.client
service1.zuul.client.DeploymentContextBasedVipAddresses=myService1 service1.zuul.client.NIWSServerListClassName=com.netflix.niws.loadbalancer.DiscoveryEnabledNIWSServerList
service2.zuul.client.DeploymentContextBasedVipAddresses=myService2 service2.zuul.client.NIWSServerListClassName=com.netflix.niws.loadbalancer.DiscoveryEnabledNIWSServerList
Now tomorrow, let's assume we need to add service3. What we have observed is that if we add those details to the same configuration (see below), they only become available to Zuul after a restart. Is there some other configuration parameter we are missing that would allow us to dynamically introduce the new service details or do we have to roll our own Eureka/Ribbon client to do this?
ribbon.client.niws.clientlist=service1|service2|service3 zuul.ribbon.namespace=zuul.client
service1.zuul.client.DeploymentContextBasedVipAddresses=myService1 service1.zuul.client.NIWSServerListClassName=com.netflix.niws.loadbalancer.DiscoveryEnabledNIWSServerList
service2.zuul.client.DeploymentContextBasedVipAddresses=myService2 service2.zuul.client.NIWSServerListClassName=com.netflix.niws.loadbalancer.DiscoveryEnabledNIWSServerList
service3.zuul.client.DeploymentContextBasedVipAddresses=myService3 service3.zuul.client.NIWSServerListClassName=com.netflix.niws.loadbalancer.DiscoveryEnabledNIWSServerList
- My other question is related and that is do we really need to add a client configuration (in eureka-client.properties) for every service that Zuul could possibly route to? At some point, we may have 100's of services running and trying to maintain all the related client configurations in Zuul seems a bit clumsy. Is there a way to globally configure Zuul to load all services into its client list from Eureka (or based on some service metadata in Eureka) and dynamically update this list as new services register themselves with Eureka?
Thanks!
