OpenShift Image Registry

It's one thing building container images and running them locally but the core reason for working with containers is to ship them around. This is done by tagging images and pushing them to image registries. Then other users can pull application container images and run them on other platforms such as OpenShift.

Note

This guide was down using OpenShift Local, see OpenShift Local

OpenShift Registry

As kubeadmin you can use this command to extract the register route:

oc get route default-route -n openshift-image-registry --template='{{ .spec.host }}'

default-route-openshift-image-registry.apps-crc.testing

Using Podman, log into the image registry using your OpenShift accounts by passing in the token, in this case the user developer:

oc login -u developer https://api.crc.testing:6443

podman login -u $(oc whoami) -p $(oc whoami -t) --tls-verify=false default-route-openshift-image-registry.apps-crc.testing

You should see:

Login Succeeded!

Assuming the following local image:

podman images

REPOSITORY                        TAG         IMAGE ID      CREATED         SIZE
localhost/fastapi-serve-static    1.0.0       e3b37b3e5276  13 minutes ago  1.37 GB

This needs to be tagged using the image registry route, project, image name and tag.

podman tag localhost/<IMAGE_NAME>:<TAG> <ROUTE>/<OPENSHIFT_PROJECT>/<IMAGE_NAME>:<TAG>

Simple Example

Create a new OpenShift project:

oc new-project example-project

Tag a local image:

podman tag localhost/fastapi-serve-static:1.0.0 default-route-openshift-image-registry.apps-crc.testing/example-project/fastapi-serve-static:1.0.0

Push the image to OpenShift image registry:

Tip

Add --tls-verify=false to work around any certificate issues.

For example:

podman push default-route-openshift-image-registry.apps-crc.testing/example-project/fastapi-serve-static:1.0.0 --tls-verify=false

You can view the image stream of a project with:

oc get is

NAME                   IMAGE REPOSITORY                                                                               TAGS    UPDATED
fastapi-serve-static   default-route-openshift-image-registry.apps-crc.testing/example-project/fastapi-serve-static   1.0.0   39 seconds ago

Deploy the application:

deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: fastapi-static-deploy
  namespace: example-project
spec:
  replicas: 1
  selector:
    matchLabels:
      app: fastapi-static-app
  template:
    metadata:
      labels:
        app: fastapi-static-app
    spec:
      containers:
      - name: fastapi-serve-static
        image: image-registry.openshift-image-registry.svc:5000/example-project/fastapi-serve-static:1.0.0
        ports:
        - containerPort: 8080

oc create -f deployment.yaml

Watch the pod progress with:

watch oc get pods

Create a service for the deployment:

service.yaml

apiVersion: v1
kind: Service
metadata:
  name: fastapi-static-svc
  namespace: example-project
  labels:
    app: fastapi-static-app
spec:
  internalTrafficPolicy: Cluster
  ipFamilies:
  - IPv4
  ipFamilyPolicy: SingleStack
  ports:
  - name: web
    port: 8080
    protocol: TCP
    targetPort: 8080
  selector:
    app: fastapi-static-app
  sessionAffinity: None
  type: ClusterIP

oc create -f service.yaml

Create a route:

route.yaml

kind: Route
apiVersion: route.openshift.io/v1
metadata:
  name: fastapi-static-route
  namespace: example-project
spec:
  to:
    kind: Service
    name: fastapi-static-svc
    weight: 100
  port:
    targetPort: 8080
  tls:
    termination: edge
    insecureEdgeTerminationPolicy: Allow
  wildcardPolicy: None

oc create -f route.yaml

You should now have the application deployed and exposed, for example https://fastapi-static-route-example-project.apps-crc.testing/.