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Version: v1.0

Attach Traits

All traits in the KubeVela system works well with the Raw K8s Object Template based Component.

In this sample, we will attach two traits, scaler and virtualgroup to a component

apiVersion: core.oam.dev/v1beta1
kind: Application
metadata:
name: myapp
namespace: default
spec:
components:
- name: mycomp
type: kube-worker
properties:
image: nginx:1.14.0
traits:
- type: scaler
properties:
replicas: 2
- type: virtualgroup
properties:
group: "my-group1"
type: "cluster"

Verify#

Deploy the application and verify traits work.

Check the scaler trait.

$ kubectl get manualscalertrait
NAME AGE
demo-podinfo-scaler-3x1sfcd34 2m
$ kubectl get deployment mycomp -o json | jq .spec.replicas
2

Check the virtualgroup trait.

$ kubectl get deployment mycomp -o json | jq .spec.template.metadata.labels
{
"app.cluster.virtual.group": "my-group1",
"app.kubernetes.io/name": "myapp"
}

Update an Application#

After the application is deployed and workloads/traits are created successfully, you can update the application, and corresponding changes will be applied to the workload.

Let's make several changes on the configuration of the sample application.

apiVersion: core.oam.dev/v1beta1
kind: Application
metadata:
name: myapp
namespace: default
spec:
components:
- name: mycomp
type: kube-worker
properties:
image: nginx:1.14.1 # 1.14.0 => 1.14.1
traits:
- type: scaler
properties:
replicas: 4 # 2 => 4
- type: virtualgroup
properties:
group: "my-group2" # my-group1 => my-group2
type: "cluster"

Apply the new configuration and check the results after several seconds.

After updating, the workload instance name will be updated from mycomp-v1 to mycomp-v2.

Check the new property value.

$ kubectl get deployment mycomp -o json | jq '.spec.template.spec.containers[0].image'
"nginx:1.14.1"

Check the scaler trait.

$ kubectl get deployment mycomp -o json | jq .spec.replicas
4

Check the virtualgroup trait.

$ kubectl get deployment mycomp -o json | jq .spec.template.metadata.labels
{
"app.cluster.virtual.group": "my-group2",
"app.kubernetes.io/name": "myapp"
}
Last updated on by Jianbo Sun