Composite Service Discovery

Some organizations use hybrid infrastructure. In such an infrastructure, different service instances may be discoverable via different service discovery providers. E.g. when serviceA is being migrated from a VM to Kubernetes, its older versions can be discovered via Consul and newer via Kubernetes.

composite service discovery addresses this problem by letting you define a service that consists of multiple services.

Dependency

To use the composite service discovery, first add the appropriate Service Discovery provider dependency to your project:

<dependency>
    <groupId>io.smallrye.stork</groupId>
    <artifactId>stork-service-discovery-composite</artifactId>
    <version>2.7.1</version>
</dependency>

Configuration

For each service that should consist of multiple services, configure the service discovery type, and set the services property to a comma separated list of services:

stork standalonestork in quarkus

stork.my-service.service-discovery.type=composite
stork.my-service.service-discovery.services=serviceA,serviceB

stork.serviceA.service-discovery.type=...
stork.serviceB.service-discovery.type=...

quarkus.stork.my-service.service-discovery.type=composite
quarkus.stork.my-service.service-discovery.services=serviceA,serviceB

quarkus.stork.serviceA.service-discovery.type=...
quarkus.stork.serviceB.service-discovery.type=...

Remember to define the services that make up your composite service.

Be aware that Stork doesn’t work as a standalone service discovery cluster. Instead, it processes composite configurations—meaning it handles multiple configurations that may use different service discovery implementation. For each specific configuration, Stork delegates the service discovery task to the appropriate service discovery provider. If one of these providers doesn’t respond or fails, it affects Stork’s ability to resolve that specific configuration, but it doesn’t mean Stork itself is faulty; it relies on the performance of the service discovery systems it’s configured to work with.

These are all the parameters of the composite service discovery:

Attribute	Mandatory	Default Value	Description
services	Yes		A comma-separated list of services that this services consists of.