sfiorini/python-k8s-sample repository overview

⁠Python K8s Sample

⁠Description

This repository contains a sample template for deploying a Python⁠ application to Kubernetes⁠.

⁠Usage

⁠Installing

For the purpose of running the sample, we are basing this document on deploying on a local Kubernetes⁠ installation that is provided by Docker Desktop⁠.

The project provides a makefile with all the commands needed to install and deploy the application.

⁠Dependencies

You will need to make sure that the following dependencies are installed on your system:

• Docker Desktop⁠and make sure you enable Kubernetes⁠
• Python⁠ version 3.9 and above.
• GNU Make⁠
• Lens⁠ (Optional: for UI view and control of K8s clusters)

⁠Setup Development Environment

• Clone this repository

• Copy .env.sample to .env and set the evironment variables as indicated in the help within the file.

• Install dependencies:

  make dependencies-install
  

  Copy

  or

  pip3 install -r requirements.txt
  

  Copy

• Run application

  make run
  

  Copy

  or

  python3 src/api.py
  

  Copy

• Open browser at http://localhost:3000⁠ and you should get the following response.

  {
   "message": "API Server is running successfully"
  }
  

  Copy

• For the OpenAPI⁠ documentation, open browser at http://localhost:3000/docs⁠

⁠Run in a Docker container

• Create Docker⁠ image (Note: the following command adds 2 tags, as latest and the current version of the app):

  docker image build . -t sfiorini/python-k8s-sample:v1.0.0  -t sfiorini/python-k8s-sample:latest
  

  Copy

  or

  make build-image
  

  Copy

• Create and run Docker⁠ container:

  docker run -d --name python-k8s-sample -p 3000:3000 sfiorini/python-k8s-sample:latest
  

  Copy

  or

  make create-run-container
  

  Copy

• Open browser at http://localhost:3000⁠ and you should get the following response.

  {
    "message": "API Server is running successfully"
  }
  

  Copy

• For the OpenAPI⁠ documentation, open browser at http://localhost:3000/docs⁠

Fore all other Docker⁠ commands, please see the Makefile⁠ reference below.

⁠Run in Kubernetes

• Create Docker⁠ image: See above section.

• Publish Docker⁠ image to registry.
  For this tutorial we assume publishing on Docker Hub⁠, however the same script will work with all other compatible registries.
  Registry account setup is beyond the scope of this documentation.

  docker push sfiorini/python-k8s-sample --all-tags
  

  Copy

  or

  make publish-image
  

  Copy

• Install NGINX Ingress Controller⁠ on Kubernetes⁠ cluster for Docker Desktop⁠.
  Note: This is a one time operation as part of setup for the cluster. For commmercial installation, more than likely the Ingress Controller is already installed by your administrator.

  kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.5.1/deploy/static/provider/cloud/deploy.yaml
  

  Copy

  or

  make install-ingress-controller
  

  Copy

• Deploy application's pod.
  Open ./kube/python-k8s-sample.yaml and replace ${PORT} with the port declared on your .env file (Default: 3000).

  kubectl apply -f ./kube/python-k8s-sample.yaml
  

  Copy

  or

  make deploy-k8s-deployment
  

  Copy

• Deploy application's service.
  Open ./kube/python-k8s-sample-service.yaml and replace ${PORT} with the port declared on your .env file (Default: 3000).

  kubectl apply -f ./kube/python-k8s-sample-service.yaml
  

  Copy

  or

  make deploy-k8s-service
  

  Copy

• Deploy application's ingress.
  Open ./kube/python-k8s-sample-ingress.yaml and replace ${PORT} with the port declared on your .env file (Default: 3000).

  kubectl apply -f ./kube/python-k8s-sample-ingress.yaml
  

  Copy

  or

  make deploy-k8s-ingress
  

  Copy

• Open browser at http://your-k8s-domain:3000⁠ and you should get the following response.
  NOTE: Docker Desktop⁠ adds domain kubernetes.docker.internal to the hosts file. Therefore your url will be http://kubernetes.docker.internal:3000⁠.

  {
    "message": "API Server is running successfully"
  }
  

  Copy

Fore all other kubectl⁠ commands, please see the Makefile⁠ reference below.

⁠Folder structure

Here's the project's folder structure:

/python-k8s-sample  # Root directory.
|- .vscode/         # Folder containing config files to develop the app using VSCode.
|- kube/            # Kubernetes deployment yaml files.
|- .gitignore       # Ignore patterns for git.
|- src              # The location of source files for the Python application
|- Dockerfile       # Metadata content (title, author...).
|- Makefile         # Makefile used for building our documents.
|- README.md        # Documentation (this file)
|- requirements.txt # Application's dependencies

⁠Makefile commands

See below a complete list of make commands for installation and maintenance of the application:

⁠References

• Python⁠
• Kubernetes⁠
• Docker Desktop⁠
• GNU Make⁠
• Lens⁠
• Docker Hub⁠
• NGINX Ingress Controller⁠
• kubectl⁠