Dev Services for Kubernetes
Dev Services for Kubernetes automatically starts a Kubernetes API server (plus the required etcd) in dev mode and when running tests. So you don’t have to start it manually. The application is configured automatically.
The following testcontainers are supported: kind, k3s or api only(default)
Enabling / Disabling Dev Services for Kubernetes
Dev Services for Kubernetes is automatically enabled unless:
-
quarkus.kubernetes-client.devservices.enabled
is set tofalse
-
the
api-server-url
is configured -
a valid Kube config file is found and
quarkus.kubernetes-client.devservices.override-kubeconfig
is not set totrue
-
you include the
quarkus-test-kubernetes-client
dependency
Dev Services for Kubernetes relies on a container engine: Docker or Podman to start the server. If your environment does not support such a container engine, you will have to start a Kubernetes cluster running in a VM, in the cloud, etc. In this case, you can configure the Kubernetes cluster access using either a Kube config file or the various properties available in the KubernetesClientBuildConfig class. |
Shared cluster
Most of the time you need to share the cluster between applications. Dev Services for Kubernetes implements a service discovery mechanism for your multiple Quarkus applications running in dev mode to share a single cluster.
Dev Services for Kubernetes starts the container with the quarkus-dev-service-kubernetes label which is used to identify the container.
|
If you need multiple (shared) clusters, you can configure the quarkus.kubernetes-client.devservices.service-name
configuration property and indicate the cluster name.
It looks for a container with the name defined, or starts a new one if none can be found.
The default service name is kubernetes
.
Sharing is enabled by default in dev mode, but disabled in test mode.
You can disable the sharing with quarkus.kubernetes-client.devservices.shared=false
.
What else for the developers
If you would like to develop test cases running top of the kubernetes cluster (launched as test container by the Dev Service), then add the following dependencies to your pom file
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-kubernetes-client</artifactId>
</dependency>
and set the Quarkus properties to select the flavor, or kube version.
Then you will be able to create a Fabric8 Kubernetes Client object able to perform many kube tasks as detailed part of this cheat sheet.
package org.acme;
import org.junit.jupiter.api.Test;
import io.fabric8.kubernetes.api.model.*;
import io.fabric8.kubernetes.client.KubernetesClient;
import io.quarkus.test.junit.QuarkusTest;
@QuarkusTest
public class ArgocdExtensionDevModeTest {
@Inject
private KubernetesClient client;
@Test
public void testCreatePod() {
client.resource(new PodBuilder()
.withMetadata(<METADATA_OBJECT>)
.withSpec(<SPEC_OBJECT>)
.build())
.inNamespace(<USER_NAMESPACE>)
.create();
}
Configuring the cluster
Dev Services for Kubernetes provides three different flavors of Kubernetes cluster. Each flavor supports different Kubernetes API versions.
You can configure the flavor and version using the quarkus.kubernetes-client.devservices.flavor
and quarkus.kubernetes-client.devservices.api-version
properties:
quarkus.kubernetes-client.devservices.flavor=api-only # k3s or kind
quarkus.kubernetes-client.devservices.api-version=1.22
api-only
only starts a Kubernetes API Server (plus the required etcd). If you need a fully-featured Kubernetes cluster that can spin up Pods, you can use k3s
or kind
. k3s
requires to start the container with privileged mode
. The kind
test container supports now to use podman rootless or rootfull.
If api-version
is not set, the latest version for the given flavor will be used. Otherwise, the version must match a version supported by the given flavor.
Configuration reference
Configuration property fixed at build time - All other configuration properties are overridable at runtime
Configuration property |
Type |
Default |
---|---|---|
If Dev Services for Kubernetes should be used. (default to true) If this is true and kubernetes client is not configured then a kubernetes cluster will be started and will be used. Environment variable: Show more |
boolean |
|
The kubernetes api server version to use. If not set, Dev Services for Kubernetes will use the latest supported version of the given flavor. see https://github.com/dajudge/kindcontainer/blob/master/k8s-versions.json Environment variable: Show more |
string |
|
The flavor to use (kind, k3s or api-only). If not set, Dev Services for Kubernetes will set it to: api-only. Environment variable: Show more |
|
|
By default, if a kubeconfig is found, Dev Services for Kubernetes will not start. Set this to true to override the kubeconfig config. Environment variable: Show more |
boolean |
|
Indicates if the Kubernetes cluster managed by Quarkus Dev Services is shared. When shared, Quarkus looks for running containers using label-based service discovery. If a matching container is found, it is used, and so a second one is not started. Otherwise, Dev Services for Kubernetes starts a new container. The discovery uses the Container sharing is only used in dev mode. Environment variable: Show more |
boolean |
|
The value of the This property is used when you need multiple shared Kubernetes clusters. Environment variable: Show more |
string |
|
Environment variables that are passed to the container. Environment variable: Show more |
Map<String,String> |