2.8. CRDs

Procedure

1. Create a YAML file for the CR. In the following example definition, the cronSpec and image custom fields are set in a CR of Kind: CronTab. The Kind comes from the spec.kind field of the CRD object:

   Example YAML file for a CR

   apiVersion: "stable.example.com/v1" 

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   kind: CronTab 

   2

   
   metadata:
     name: my-new-cron-object 

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     finalizers: 

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     - finalizer.stable.example.com
   spec: 

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     cronSpec: "* * * * /5"
     image: my-awesome-cron-image

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   Specify the group name and API version (name/version) from the CRD.

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   Specify the type in the CRD.

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   Specify a name for the object.

   4

   Specify the finalizers for the object, if any. Finalizers allow controllers to implement conditions that must be completed before the object can be deleted.

   5

   Specify conditions specific to the type of object.

2. After you create the file, create the object:

   $ oc create -f <file_name>.yaml

Procedure

1. To get information on a specific kind of a CR, run:

   $ oc get <kind>

   For example:

   $ oc get crontab

   Example output

   NAME                 KIND
   my-new-cron-object   CronTab.v1.stable.example.com

   Resource names are not case-sensitive, and you can use either the singular or plural forms defined in the CRD, as well as any short name. For example:

   $ oc get crontabs

   $ oc get crontab

   $ oc get ct

2. You can also view the raw YAML data for a CR:

   $ oc get <kind> -o yaml

   For example:

   $ oc get ct -o yaml

   Example output

   apiVersion: v1
   items:
   - apiVersion: stable.example.com/v1
     kind: CronTab
     metadata:
       clusterName: ""
       creationTimestamp: 2017-05-31T12:56:35Z
       deletionGracePeriodSeconds: null
       deletionTimestamp: null
       name: my-new-cron-object
       namespace: default
       resourceVersion: "285"
       selfLink: /apis/stable.example.com/v1/namespaces/default/crontabs/my-new-cron-object
       uid: 9423255b-4600-11e7-af6a-28d2447dc82b
     spec:
       cronSpec: '* * * * /5' 

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       image: my-awesome-cron-image 

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   Custom data from the YAML that you used to create the object displays.