Extending kubernetes resources

This section describes how you can extend Kubernetes resources for container components through pod-overrides and container-overrides attributes.

container-overrides

container-overrides attributes allow you to override properties of a container in a pod spec such as securityContext and resources. However, it restricts from overriding properties such as image, name, ports, env, volumesMounts, command, and args.

This attribute can be defined at the component level.

Procedure

1. Specify "container-overrides" at the component level.

   Specify container-overrides to override security context for container at component level

   devfile.yaml

   schemaVersion: 2.3.0
   components:
     - name: maven
       attributes:
         container-overrides:
           securityContext:
             runAsUser: 1001
             runAsGroup: 1001
       container:
         image: eclipse/maven-jdk8:latest
   

The data inside container-overrides can also be specified as a JSON.

  container-overrides:
    securityContext: {"runAsUser": 1001, "runAsGroup": 1001}

pod-overrides

pod-overrides attribute allow you to override properties of a pod spec such as securityContext, serviceAccountName, schedulerName, etc. However, it restricts overriding properties such as containers, initContainers, and volumes.

This attribute can be defined at the component and devfile attributes levels. If it is defined at both the levels, the attribute at the devfile attributes level will be parsed first and then the component level.Strategic Merge Patch strategy is used to merge the attributes defined at both the levels.

Procedure

1. Specify "pod-overrides" at the component level.

   Specify pod-overrides to override security context for container at component level

   devfile.yaml

   schemaVersion: 2.3.0
   components:
     - name: maven
       attributes:
         pod-overrides:
           spec:
             serviceAccountName: new-service-account
       container:
         image: eclipse/maven-jdk8:latest
   

2. Specify "pod-overrides" at the devfile attributes level. It will be defined as a top-level attribute.

   Specify pod-overrides to override resources for container at the devfile level

   devfile.yaml

   schemaVersion: 2.3.0
   attributes:
     pod-overrides:
       spec:
         serviceAccountName: new-service-account
   components:
     - name: maven
       container:
         image: eclipse/maven-jdk8:latest
   

The data inside pod-overrides can also be specified as a JSON.

  pod-overrides:
    spec: {"serviceAccountName": "new-service-account"}

Additional resources

• Defining Attributes
• Strategic Merge Patch