1.2. kn service commands in offline mode

Procedure

1. In offline mode, create a local Knative service descriptor file:

   $ kn service create showcase \
       --image quay.io/openshift-knative/showcase \
       --target ./ \
       --namespace test

   Example output

   Service 'showcase' created in namespace 'test'.

   • The --target ./ flag enables offline mode and specifies ./ as the directory for storing the new directory tree.

     If you do not specify an existing directory, but use a filename, such as --target my-service.yaml, then no directory tree is created. Instead, only the service descriptor file my-service.yaml is created in the current directory.

     The filename can have the .yaml, .yml, or .json extension. Choosing .json creates the service descriptor file in the JSON format.

   • The --namespace test option places the new service in the test namespace.

     If you do not use --namespace, and you are logged in to an OpenShift Container Platform cluster, the descriptor file is created in the current namespace. Otherwise, the descriptor file is created in the default namespace.

2. Examine the created directory structure:

   $ tree ./

   Example output

   ./
   └── test
       └── ksvc
           └── showcase.yaml
   
   2 directories, 1 file

   • The current ./ directory specified with --target contains the new test/ directory that is named after the specified namespace.
   • The test/ directory contains the ksvc directory, named after the resource type.
   • The ksvc directory contains the descriptor file showcase.yaml, named according to the specified service name.

3. Examine the generated service descriptor file:

   $ cat test/ksvc/showcase.yaml

   Example output

   apiVersion: serving.knative.dev/v1
   kind: Service
   metadata:
     creationTimestamp: null
     name: showcase
     namespace: test
   spec:
     template:
       metadata:
         annotations:
           client.knative.dev/user-image: quay.io/openshift-knative/showcase
         creationTimestamp: null
       spec:
         containers:
         - image: quay.io/openshift-knative/showcase
           name: ""
           resources: {}
   status: {}

4. List information about the new service:

   $ kn service describe showcase --target ./ --namespace test

   Example output

   Name:       showcase
   Namespace:  test
   Age:
   URL:
   
   Revisions:
   
   Conditions:
     OK TYPE    AGE REASON

   • The --target ./ option specifies the root directory for the directory structure containing namespace subdirectories.

     Alternatively, you can directly specify a YAML or JSON filename with the --target option. The accepted file extensions are .yaml, .yml, and .json.

   • The --namespace option specifies the namespace, which communicates to kn the subdirectory that contains the necessary service descriptor file.

     If you do not use --namespace, and you are logged in to an OpenShift Container Platform cluster, kn searches for the service in the subdirectory that is named after the current namespace. Otherwise, kn searches in the default/ subdirectory.

5. Use the service descriptor file to create the service on the cluster:

   $ kn service create -f test/ksvc/showcase.yaml

   Example output

   Creating service 'showcase' in namespace 'test':
   
     0.058s The Route is still working to reflect the latest desired specification.
     0.098s ...
     0.168s Configuration "showcase" is waiting for a Revision to become ready.
    23.377s ...
    23.419s Ingress has not yet been reconciled.
    23.534s Waiting for load balancer to be ready
    23.723s Ready to serve.
   
   Service 'showcase' created to latest revision 'showcase-00001' is available at URL:
   http://showcase-test.apps.example.com