Collection Resource

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For collection resource, refer to What is Collection Resource

Due to the limitation of kubectl, we cannot pass search conditions through Label Selector or other methods, so it is recommended to search for Collection Resource by using a URL.

When requesting Collection Resource, you shall use paging because the number of resources may be very large.

kubectl get --raw="/apis/clusterpedia.io/v1beta1/collectionresources/workloads?limit=1" | jq

# Output
{
  "kind": "CollectionResource",
  "apiVersion": "clusterpedia.io/v1beta1",
  "metadata": {
    "name": "workloads",
    "creationTimestamp": null
  },
  "resourceTypes": [
    {
      "group": "apps",
      "version": "v1",
      "kind": "Deployment",
      "resource": "deployments"
    },
    {
      "group": "apps",
      "version": "v1",
      "resource": "daemonsets"
    },
    {
      "group": "apps",
      "version": "v1",
      "resource": "statefulsets"
    }
  ],
  "items": [
    {
      "apiVersion": "apps/v1",
      "kind": "Deployment",
      ...
    }
  ]
}

The complex search of Collection Resource is basically the same as the function of multi-cluster resource search, only some operations are not supported:

  • Search by Owner is not supported. If you need to specify a specific resource type to search by Owner, you can refer to multi-cluster resource search and specified cluster search
  • Getting a specific single resource in Collection Resource is not supported, because you shall specify cluster and type for a specific resource. In this case, you can use Get a single resource.

It is not easy to search for Collection Resource by using kubectl. However, you can have a try.

kubectl cannot pass pages and other search conditions and may get all Collection Resources at one time. It is not recommended to use kubectl to view Collection Resource if a large number of clusters are imported or a cluster has many deployments, daemonsets and statefulsets resources.

kubectl get collectionresources workloads

# Output
CLUSTER     GROUP   VERSION   KIND         NAMESPACE                     NAME                                          AGE
cluster-1   apps    v1        DaemonSet    kube-system                   vsphere-cloud-controller-manager              63d
cluster-2   apps    v1        Deployment   kube-system                   calico-kube-controllers                       109d
cluster-2   apps    v1        Deployment   kube-system                   coredns-coredns                               109d
...

Search for Collection Resource by using URL

Only Metadata

When we retrieve a CollectionResource, the default resource is the full resource content, but sometimes we just need to retrieve the metadata of the resource.

We can use url query – onlyMetadata to retrieve only the resource metadata when retrieving.

$ kubectl get --raw "/apis/clusterpedia.io/v1beta1/collectionresources/workloads?onlyMetadata=true&limit=1" | jq
{
  "kind": "CollectionResource",
  "apiVersion": "clusterpedia.io/v1beta1",
  "metadata": {
    "name": "workloads",
    "creationTimestamp": null
  },
  "resourceTypes": [
    {
      "group": "apps",
      "version": "v1",
      "kind": "Deployment",
      "resource": "deployments"
    }
  ],
  "items": [
    {
      "apiVersion": "apps/v1",
      "kind": "Deployment",
      "metadata": {
        "annotations": {
          "deployment.kubernetes.io/revision": "1",
          "shadow.clusterpedia.io/cluster-name": "cluster-example"
        },
        "creationTimestamp": "2021-09-24T10:19:19Z",
        "generation": 1,
        "labels": {
          "k8s-app": "tigera-operator"
        },
        "name": "tigera-operator",
        "namespace": "tigera-operator",
        "resourceVersion": "125073610",
        "uid": "992f9d53-37cb-4184-a004-15b278b11f79"
      }
    }
  ]
}

Any CollectionResource

any collectionresource is one of the ways that users can freely combine resource types with custom collection resources to see more.

clusterpedia supports a special CollectionResource —— any.

$ kubectl get collectionresources
NAME            RESOURCES
any             *

When retrieving any collectionresource, we must specify a set of resource types by url query, so we can only retrieve any collectionresource via clusterpedia-io/client-go or URL.

$ kubectl get collectionresources any
Error from server (BadRequest): url query - `groups` or `resources` is required

any collectionresource supports two url queries —— groups and resources

groups and resources can be specified together, currently they are taken together and are not de-duplicated, the caller is responsible for de-duplication, there are some future optimizations for this behavior.

$ kubectl get --raw "/apis/clusterpedia.io/v1beta1/collectionresources/any?onlyMetadata=true&groups=apps&resources=batch/jobs,batch/cronjobs" | jq

groups

groups can specify a group and version of a set of resources, with multiple group versions separated by ,,

the group version format is < group >/< version >, or no version can be specified < group >, for resources under /api, you can just use the empty string.

Example: groups=apps/v1,,batch specifies three groups apps/v1, core, batch.

resources

resources can specify a specific resource type, multiple resource types are separated by ,,

the resource type format is < group >/< version >/< resource>, by also not specifying the version < group >/< resource >.

Example: resources=apps/v1/deployments,apps/daemonsets,/pods specifies three resources deloyments, daemonsets and pods.