benn1440/dockerized_app

Create a simple web application, Dockerize it, and run it on Minikube Kubernetes cluster.

This is a simple Python application that displays a welcome message.

Dockerize the application:

Write a Dockerfile to containerize the application.

Build the Docker image and run it locally to ensure it works correctly.

Docker ps

Tag it and Push the Docker image to a container registry (e.g., Docker Hub).

Running Container on Docker Desktop

Docker Inspect

Tag Image and push to Docker Hub with Link

https://hub.docker.com/layers/benn1440/python_app/Latest/images/sha256:1f4a2f43a5a2269bc46e280a5154e8eacd26d2271e2d50fea7fe371bd42bd55b?uuid=a6cfa028-74f7-47b1-8a34-2d8176dae4e3%0A

Deploy the application to a Kubernetes cluster:

• Spin up Minikube for Local development

  

• Minikube was spinned up with docker driver

Create a Kubernetes manifest file for a Deployment to deploy the Docker image.

Deploy the app to minikube cluster

$ kubectl apply -f deployment.yaml

Kubectl describe deployment

$ kubectl describe deployment python-app-deployment

Errors and Troubleshooting

When I try to list the Pods created by the deployment, I noticed the pods were on ImagePullBackOff,

$ kubectl get pods -l app=python-app

To resolve this I had to check the Image name that was deployed and noticed a slight difference in the name

Pod in running state after using the appropriate Image; changes were made on the deployment file and then redeployed.

Create a Kubernetes Service of type ClusterIP to expose the application.

$ kubectl get svc

Test the deployment:

• Port-forward the service to a local host port and access it through a web browser.

  $ kubectl port-forward service/python-app-service 8080:80

Errors and Troubleshooting

When I copy the localhost port and input on the browser, the Pod lost connection and throws this error

To resolve this, I noticed that the target port on my deployment and service was different from the port my app was running (5500), this was corrected and the deployment and service were reapplied

$ kubectl apply -f deployment.yaml $ kubectl apply -f service.yaml

Verify that the application displays the expected message.

• https://kubernetes.io/docs/tasks/access-application-cluster/port-forward-access-application-cluster/

Application running on Port forwarded port

Implementing secrets

https://kubernetes.io/docs/concepts/configuration/secret/