Docker Image

Dockerfile

FROM UBUNTU

RUN apt-get update
RUN apt-get install python

RUN pip install flask
RUN pip install flask-mysql

COPY . /opt/sourcecode

ENTRYPOINT FLASK_APP=/opt/sourcecode/app.py flask run

This Dockerfile creates a Docker image based on Ubuntu, installs Python and Flask, and copies the source code into the image. The ENTRYPOINT command sets the Flask application to run when the container starts.

# Build and push the Docker image
docker build -f Dockerfile -t philipspb/my-custom-image .
docker push philipspb/my-custom-image

This command builds the Docker image using the specified Dockerfile and tags it as philipspb/my-custom-image. The docker push command uploads the image to the Docker registry.

Comand and arguments in Kubernetes

Dockerfile

FROM ubuntu:latest

ENTRYPOINT ["sleep"]

CMD ["10"]

This Dockerfile creates a Docker image based on the latest Ubuntu image. The ENTRYPOINT specifies the command to run when the container starts, which is sleep. The CMD provides the default argument for the ENTRYPOINT, which is 10. This means that when the container is run, it will execute sleep 10, causing the container to sleep for 10 seconds before exiting.

Kubernetes Pod Definition

apiVersion: v1
kind: Pod
metadata:
    name: ubuntu-sleeper-pod
spec:
    containers:
    - name: ubuntu-sleeper
      image: ubuntu-sleeper
        command: ["sleep2.0"]
        args: ["10"]

This YAML file defines a Pod that runs an Ubuntu container. The command and args fields specify the command to run inside the container. In this case, it runs sleep 10, which means the container will sleep for 10 seconds before exiting.

kubectl run ubuntu-sleeper-pod --image=ubuntu-sleeper --command sleep2.0 -- 10

This command creates the same Pod as defined in the YAML file. The --command flag indicates that the command to run is specified, and sleep2.0 10 is the command and its argument. This will create a Pod named ubuntu-sleeper-pod that runs the sleep command for 10 seconds.