DockerApp

A simple Flask weather application demonstrating Kubernetes deployment with minikube. This project showcases how to containerize a web application and deploy it to a local Kubernetes cluster with proper scaling, health checks, and service exposure.

Purpose

This project is designed to demonstrate Kubernetes deployment and steps to:

• Containerize a Flask web application
• Deploy applications to Kubernetes using manifests
• Configure services for external access
• Implement health checks and resource management
• Scale applications with multiple replicas
• Use minikube for local Kubernetes development

The Weather App

The application provides weather forecasts using the U.S. National Weather Service API:

• City-based Search: Enter any U.S. city name
• Current Weather: Real-time temperature and conditions
• Hourly Forecast: 24-hour detailed predictions
• 7-Day Forecast: Weekly outlook with high/low temperatures
• Temperature Conversion: Both Fahrenheit and Celsius

Tech Stack

• Application: Python Flask web framework
• Containerization: Docker
• Orchestration: Kubernetes (minikube)
• APIs: National Weather Service + OpenStreetMap Nominatim

Kubernetes Deployment

Prerequisites

• minikube - Local Kubernetes cluster
• kubectl - Kubernetes command-line tool
• Docker - Container runtime
  • macOS/Windows: Docker Desktop
  • Linux: Docker Engine

Installation

macOS:

brew install minikube

Windows:

# Using Chocolatey
choco install minikube

# Or using winget
winget install Kubernetes.minikube

# Or download directly from: https://minikube.sigs.k8s.io/docs/start/

Linux:

curl -LO https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64
sudo install minikube-linux-amd64 /usr/local/bin/minikube

Deployment Steps

1. Clone and navigate to the project

   git clone https://github.com/costello-aaron/DockerApp
   cd DockerApp

2. Start minikube cluster

   minikube start

3. Configure Docker to use minikube's Docker daemon

   macOS/Linux:

   eval $(minikube docker-env)

   Windows (PowerShell):

   minikube docker-env | Invoke-Expression

   Windows (Command Prompt):

   @FOR /f "tokens=*" %i IN ('minikube docker-env') DO @%i

4. Build the Docker image inside minikube

   docker build -t weather-app:latest .

5. Deploy the application to Kubernetes

   kubectl apply -f k8s-deployment.yaml
   kubectl apply -f k8s-service.yaml

6. Get the service URL and access the app

   minikube service weather-app-service --url

   Open the returned URL in your browser.

   Note: On Windows, you may need to use the minikube IP instead of localhost. The command above will provide the correct URL for your platform.

Verify Deployment

# Check pods are running
kubectl get pods

# Check service status
kubectl get services

# View application logs
kubectl logs deployment/weather-app