Use Docker Registry Internally

This tutorial shows how you can push an image to the Docker Registry and use it.

Prerequsities

• Kyma CLI v3
• kubectl
• Docker

Steps

1. Create a simple.py file, and paste the following content:

   import time
   import datetime
    
   while True:
     print("Current time:", datetime.datetime.now(), flush=True)
     time.sleep(10)

2. Create Dockerfile with the following content:

   FROM python:3-alpine
   
   WORKDIR /usr/src/app
   
   COPY simple.py .
   
   CMD [ "python", "./simple.py" ]

3. Build and push the image to Docker Registry:

   docker build -t simple-image .

4. Import the image to Docker Registry:

   kyma registry image-import simple-image:latest

5. Create a Pod using the image from Docker Registry:

   export REGISTRY_INTERNAL_PULL_ADDRESS=$(kyma registry config-internal --pull-reg-addr)
   kubectl run simple-pod --image="${REGISTRY_INTERNAL_PULL_ADDRESS}/simple-image:latest" --overrides='{ "spec": { "imagePullSecrets": [ { "name": "dockerregistry-config" } ] } }'

   NOTE

   An image pull secret with the name dockerregistry-config is created in every namespace of the cluster.

6. Check if the Pod is running:

   kubectl get pods simple-pod

   Expected output:

   NAME         READY   STATUS    RESTARTS   AGE
   simple-pod   1/1     Running   0          60s

7. Use the following command to print the current time every 10 seconds:

   kubectl logs simple-pod

   Expected output:

   Current time: 2024-05-17 11:23:34.957406
   Current time: 2024-05-17 11:23:44.954583
   Current time: 2024-05-17 11:23:54.956107
   Current time: 2024-05-17 11:24:04.966306