Working with CompleteState

CompleteState

The complete state data structure CompleteState is used for building a request to Ankaios server to change or receive the state of the Ankaios system. It contains the startupState which describes the states provided at the start of the Ankaios system via the startup configuration, the desiredState which describes the state of the Ankaios system the user wants to have and the workloadStates which gives the information about the execution state of all the workloads. By using of CompleteState in conjunction with the object field mask specific parts of the Ankaios state could be retrieved or updated.

Example: ank get state returns the complete state of Ankaios system:

startupState:
  apiVersion: v0.1
  workloads: {}
desiredState:
  apiVersion: v0.1
  workloads:
    hello-pod:
      agent: agent_B
      tags:
      - key: owner
        value: Ankaios team
      dependencies: {}
      restartPolicy: NEVER
      runtime: podman-kube
      runtimeConfig: |
        manifest: |
          apiVersion: v1
          kind: Pod
          metadata:
            name: hello-pod
          spec:
            restartPolicy: Never
            containers:
            - name: looper
              image: alpine:latest
              command:
              - sleep
              - 50000
            - name: greater
              image: alpine:latest
              command:
              - echo
              - "Hello from a container in a pod"
    hello1:
      agent: agent_B
      tags:
      - key: owner
        value: Ankaios team
      dependencies: {}
      runtime: podman
      runtimeConfig: |
        image: alpine:latest
        commandOptions: [ "--rm"]
        commandArgs: [ "echo", "Hello Ankaios"]
    hello2:
      agent: agent_B
      tags:
      - key: owner
        value: Ankaios team
      dependencies: {}
      restartPolicy: ALWAYS
      runtime: podman
      runtimeConfig: |
        image: alpine:latest
        commandOptions: [ "--entrypoint", "/bin/sh" ]
        commandArgs: [ "-c", "echo 'Always restarted.'; sleep 2"]
    nginx:
      agent: agent_A
      tags:
      - key: owner
        value: Ankaios team
      dependencies: {}
      restartPolicy: ON_FAILURE
      runtime: podman
      runtimeConfig: |
        image: docker.io/nginx:latest
        commandOptions: ["-p", "8081:80"]
workloadStates: []

It is not necessary to provide the whole structure of the the CompleteState data structure when using it in conjunction with the object field mask. It is sufficient to provide the relevant branch of the CompleteState object. As an example, to change the restart behavior of the nginx workload, only the relevant branch of the CompleteState needs to be provided:

desiredState:
  workloads:
    nginx:
      restartPolicy: ALWAYS

Object field mask

With the object field mask only specific parts of the Ankaios state could be retrieved or updated. The object field mask can be constructed using the field names of the CompleteState data structure:

<top level field name>.<second level field name>.<third level field name>.<...>

1. Example: ank get state desiredState.workloads.nginx returns only the information about nginx workload:

 desiredState:
   workloads:
     nginx:
       agent: agent_A
       tags:
       - key: owner
         value: Ankaios team
       dependencies: {}
       restartPolicy: ALWAYS
       runtime: podman
       runtimeConfig: |
         image: docker.io/nginx:latest
         commandOptions: ["-p", "8081:80"]

1. Example ank get state desiredState.workloads.nginx.runtimeConfig returns only the runtime configuration of nginx workload:

desiredState:
  workloads:
    nginx:
      runtimeConfig: |
        image: docker.io/nginx:latest
        commandOptions: ["-p", "8081:80"]

1. Example ank set state -f new-state.yaml desiredState.workloads.nginx.restartPolicy changes the restart behavior of nginx workload to NEVER:

new-state.yaml

desiredState:
  workloads:
    nginx:
      restartPolicy: NEVER