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58
README.md
58
README.md
@ -1,58 +0,0 @@
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# Docker Web Application
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## Prerequisites
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- Docker installed on the system.
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## Application Description
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This is a simple Flask web application running inside a Docker container. The app accepts user input via a form and displays the submitted data.
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## Docker Setup
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1. **Preparation**
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Run the following command to set up the environment:
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```bash
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./prepare-app.sh
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```
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2. **Start the Application**
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Start the application with:
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```bash
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./start-app.sh
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```
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The app will be available at: [http://localhost:5000](http://localhost:5000)
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3. **Stop the Application**
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To stop the application:
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```bash
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./stop-app.sh
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```
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4. **Remove the Application**
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To remove all Docker containers, networks, and volumes:
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```bash
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./remove-app.sh
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```
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## Working Example
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1. Prepare the application:
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```bash
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./prepare-app.sh
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```
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2. Start the app:
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```bash
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./start-app.sh
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```
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3. Visit [http://localhost:5000](http://localhost:5000) in a browser.
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4. Stop the app:
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```bash
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./stop-app.sh
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```
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5. Remove the app:
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```bash
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./remove-app.sh
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```
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## Conclusion
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This application demonstrates Docker containerization of a Flask app with basic form handling.
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@ -1,18 +0,0 @@
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version: '3.8'
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services:
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flask-app:
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build: .
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ports:
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- "5000:5000"
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networks:
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- flask-network
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restart: unless-stopped
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# You can add other services here, like a database if required
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networks:
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flask-network:
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driver: bridge
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volumes:
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flask-data:
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driver: local
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21
dockerfile
21
dockerfile
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# Use an official Python runtime as a parent image
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FROM python:3.8-slim
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# Set the working directory inside the container
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WORKDIR /app
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# Copy the current directory contents into the container at /app
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COPY . /app
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# Install Flask
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RUN pip install --no-cache-dir flask
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# Set the environment variable for Flask
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ENV FLASK_APP=testapp.py
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ENV FLASK_RUN_HOST=0.0.0.0
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# Expose port 5000 for the Flask app
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EXPOSE 5000
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# Run the Flask application
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CMD ["flask", "run", "--host=0.0.0.0", "--port=5000"]
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#!/bin/bash
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# Create a Docker network
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echo "Creating Docker network..."
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docker network create flask-network
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# Create a named volume for persistent storage (for example, for database)
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echo "Creating Docker volume..."
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docker volume create flask-data
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echo "Preparation complete!"
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#!/bin/bash
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# Remove the Flask app container
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echo "Removing Flask app container..."
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docker rm flask-app
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# Remove Docker network
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echo "Removing Docker network..."
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docker network rm flask-network
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# Remove Docker volume
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echo "Removing Docker volume..."
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docker volume rm flask-data
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echo "App removed successfully!"
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#!/bin/bash
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# Start the Flask app container
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echo "Starting Flask app container..."
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docker run -d --restart unless-stopped --name flask-app --network flask-network -p 5000:5000 flask-app
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# Optionally, start any additional services (like a database) here if needed
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echo "App is running at http://localhost:5000"
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#!/bin/bash
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# Stop the Flask app container
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echo "Stopping Flask app container..."
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docker stop flask-app
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# Optionally, stop other services like the database here
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echo "App stopped successfully!"
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26
testapp.py
26
testapp.py
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from flask import Flask, render_template, request
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app = Flask(__name__)
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@app.route('/', methods=['GET', 'POST'])
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def home():
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if request.method == 'POST':
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college_name = request.form['college_name']
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student_name = request.form['student_name']
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course_name = request.form['course_name']
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year_of_study = request.form['year_of_study']
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return f"College: {college_name}, Student: {student_name}, Course: {course_name}, Year: {year_of_study}"
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return '''
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<form method="POST">
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College Name: <input type="text" name="college_name"><br>
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Student Name: <input type="text" name="student_name"><br>
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Course Name: <input type="text" name="course_name"><br>
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Year of Study: <input type="text" name="year_of_study"><br>
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<input type="submit" value="Submit">
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</form>
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'''
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if __name__ == "__main__":
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app.run(debug=True, host="0.0.0.0", port=5000) # This allows the app to run inside the container
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9
z1/Dockerfile
Normal file
9
z1/Dockerfile
Normal file
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FROM python:3.9-slim
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WORKDIR /app
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COPY app/ .
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RUN pip install --no-cache-dir -r requirements.txt
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CMD ["python", "main.py"]
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32
z1/README.md
Normal file
32
z1/README.md
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# Flask + PostgreSQL Kubernetes Deployment
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This project deploys a Flask web application with a PostgreSQL backend using Kubernetes.
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## 🛠 Structure
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- `app/`: Flask source code (`main.py`, `requirements.txt`)
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- `k8s/`: Kubernetes manifests for deployments, services, namespace, etc.
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- `Dockerfile`: Builds the Flask app image
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- `prepare-app.sh`: Builds Docker image and prepares volumes
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- `start-app.sh`: Applies all Kubernetes objects
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- `stop-app.sh`: Deletes all Kubernetes resources
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- `statefulset.yaml`: Defines StatefulSet, PV, and PVC
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## 🚀 Steps to Deploy
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1. **Prepare the application:**
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```bash
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./prepare-app.sh
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hafzal03@LAPTOP-ELUS3HGM:~/mypro/z2$ kubectl get pods -n webapp-namespace
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NAME READY STATUS RESTARTS AGE
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flask-app-6b844bf6-cq9t6 1/1 Running 0 8m37s
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postgres-644fc4c86d-l9h4f 1/1 Running 0 14m
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hafzal03@LAPTOP-ELUS3HGM:~/mypro/z2$ minikube service flask-service -n webapp-namespace
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minikube service flask-service -n webapp-namespace
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kubectl get pods -n webapp-namespace
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kubectl rollout restart deployment flask-app -n webapp-namespace
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81
z1/app/main.py
Normal file
81
z1/app/main.py
Normal file
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from flask import Flask, request, jsonify, render_template_string
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import psycopg2
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import os
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app = Flask(__name__)
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def get_db_connection():
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return psycopg2.connect(
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host=os.environ.get("POSTGRES_HOST"),
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database=os.environ.get("POSTGRES_DB"),
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user=os.environ.get("POSTGRES_USER"),
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password=os.environ.get("POSTGRES_PASSWORD"),
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port=os.environ.get("POSTGRES_PORT", 5432),
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)
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def init_db():
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conn = get_db_connection()
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cur = conn.cursor()
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cur.execute("""
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CREATE TABLE IF NOT EXISTS students (
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id SERIAL PRIMARY KEY,
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name TEXT NOT NULL,
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room_number TEXT NOT NULL,
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faculty TEXT NOT NULL
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);
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""")
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conn.commit()
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cur.close()
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conn.close()
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@app.route("/")
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def index():
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return "<h1>Welcome!</h1><p>Go to /add to add a student, /students to view all.</p>"
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# HTML Form + POST Submission
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@app.route("/add", methods=["GET", "POST"])
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def add_student():
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if request.method == "POST":
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name = request.form.get("name")
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room_number = request.form.get("room_number")
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faculty = request.form.get("faculty")
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if not name or not room_number or not faculty:
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return "All fields are required!", 400
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conn = get_db_connection()
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cur = conn.cursor()
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cur.execute("INSERT INTO students (name, room_number, faculty) VALUES (%s, %s, %s)", (name, room_number, faculty))
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conn.commit()
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cur.close()
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conn.close()
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return "<p>Student added successfully!</p><a href='/add'>Add another</a>"
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# HTML form
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return render_template_string("""
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<h2>Add Student</h2>
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<form method="post">
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Name: <input name="name"><br>
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Room Number: <input name="room_number"><br>
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Faculty: <input name="faculty"><br>
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<input type="submit" value="Add Student">
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</form>
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""")
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# View all students
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@app.route("/students", methods=["GET"])
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def get_students():
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conn = get_db_connection()
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cur = conn.cursor()
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cur.execute("SELECT id, name, room_number, faculty FROM students")
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rows = cur.fetchall()
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cur.close()
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conn.close()
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|
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|
return jsonify([
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|
{"id": row[0], "name": row[1], "room_number": row[2], "faculty": row[3]} for row in rows
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|
])
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|
|
||||||
|
if __name__ == "__main__":
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|
init_db()
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|
app.run(host="0.0.0.0", port=8000)
|
5
z1/app/requirements.txt
Normal file
5
z1/app/requirements.txt
Normal file
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|
Flask==2.0.1
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|
Werkzeug==2.0.3
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|
psycopg2-binary==2.9.1
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|
python-dotenv==0.19.0
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|
Jinja2==3.0.3
|
32
z1/k8s/deployment.yaml
Normal file
32
z1/k8s/deployment.yaml
Normal file
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|||||||
|
apiVersion: apps/v1
|
||||||
|
kind: Deployment
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||||||
|
metadata:
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|
name: flask-app
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||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
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||||||
|
replicas: 1
|
||||||
|
selector:
|
||||||
|
matchLabels:
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||||||
|
app: flask
|
||||||
|
template:
|
||||||
|
metadata:
|
||||||
|
labels:
|
||||||
|
app: flask
|
||||||
|
spec:
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||||||
|
containers:
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||||||
|
- name: flask
|
||||||
|
image: flask-app:latest
|
||||||
|
imagePullPolicy: Never
|
||||||
|
ports:
|
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|
- containerPort: 8000
|
||||||
|
env:
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||||||
|
- name: POSTGRES_HOST
|
||||||
|
value: postgres
|
||||||
|
- name: POSTGRES_DB
|
||||||
|
value: mydatabase
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||||||
|
- name: POSTGRES_USER
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||||||
|
value: myuser
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||||||
|
- name: POSTGRES_PASSWORD
|
||||||
|
value: mypassword
|
||||||
|
- name: POSTGRES_PORT
|
||||||
|
value: "5432"
|
12
z1/k8s/migrate-job.yaml
Normal file
12
z1/k8s/migrate-job.yaml
Normal file
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|
|||||||
|
apiVersion: batch/v1
|
||||||
|
kind: Job
|
||||||
|
metadata:
|
||||||
|
name: migrate
|
||||||
|
spec:
|
||||||
|
template:
|
||||||
|
spec:
|
||||||
|
containers:
|
||||||
|
- name: migrator
|
||||||
|
image: myapp:latest
|
||||||
|
command: ["python", "manage.py", "migrate"]
|
||||||
|
restartPolicy: Never
|
4
z1/k8s/namespace.yaml
Normal file
4
z1/k8s/namespace.yaml
Normal file
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|
|||||||
|
apiVersion: v1
|
||||||
|
kind: Namespace
|
||||||
|
metadata:
|
||||||
|
name: webapp-namespace
|
57
z1/k8s/postgres-deployment.yaml
Normal file
57
z1/k8s/postgres-deployment.yaml
Normal file
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|
|||||||
|
apiVersion: v1
|
||||||
|
kind: PersistentVolumeClaim
|
||||||
|
metadata:
|
||||||
|
name: postgres-pvc
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
accessModes:
|
||||||
|
- ReadWriteOnce
|
||||||
|
resources:
|
||||||
|
requests:
|
||||||
|
storage: 1Gi
|
||||||
|
---
|
||||||
|
apiVersion: apps/v1
|
||||||
|
kind: Deployment
|
||||||
|
metadata:
|
||||||
|
name: postgres
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
replicas: 1
|
||||||
|
selector:
|
||||||
|
matchLabels:
|
||||||
|
app: postgres
|
||||||
|
template:
|
||||||
|
metadata:
|
||||||
|
labels:
|
||||||
|
app: postgres
|
||||||
|
spec:
|
||||||
|
containers:
|
||||||
|
- name: postgres
|
||||||
|
image: postgres:13
|
||||||
|
env:
|
||||||
|
- name: POSTGRES_DB
|
||||||
|
value: mydatabase
|
||||||
|
- name: POSTGRES_USER
|
||||||
|
value: myuser
|
||||||
|
- name: POSTGRES_PASSWORD
|
||||||
|
value: mypassword
|
||||||
|
ports:
|
||||||
|
- containerPort: 5432
|
||||||
|
volumeMounts:
|
||||||
|
- name: postgres-storage
|
||||||
|
mountPath: /var/lib/postgresql/data
|
||||||
|
volumes:
|
||||||
|
- name: postgres-storage
|
||||||
|
persistentVolumeClaim:
|
||||||
|
claimName: postgres-pvc
|
||||||
|
---
|
||||||
|
apiVersion: v1
|
||||||
|
kind: Service
|
||||||
|
metadata:
|
||||||
|
name: postgres
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
selector:
|
||||||
|
app: postgres
|
||||||
|
ports:
|
||||||
|
- port: 5432
|
13
z1/k8s/service.yaml
Normal file
13
z1/k8s/service.yaml
Normal file
@ -0,0 +1,13 @@
|
|||||||
|
apiVersion: v1
|
||||||
|
kind: Service
|
||||||
|
metadata:
|
||||||
|
name: flask-service
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
selector:
|
||||||
|
app: flask
|
||||||
|
type: NodePort
|
||||||
|
ports:
|
||||||
|
- port: 8000
|
||||||
|
targetPort: 8000
|
||||||
|
nodePort: 30080 # <-- Changed this
|
10
z1/prepare-app.sh
Executable file
10
z1/prepare-app.sh
Executable file
@ -0,0 +1,10 @@
|
|||||||
|
#!/bin/bash
|
||||||
|
|
||||||
|
echo "Building Docker image for Flask app..."
|
||||||
|
docker build -t flask-app:latest .
|
||||||
|
|
||||||
|
echo "Creating Minikube image cache (if using Minikube)..."
|
||||||
|
eval $(minikube docker-env)
|
||||||
|
docker build -t flask-app:latest .
|
||||||
|
|
||||||
|
echo "Preparation complete."
|
18
z1/start-app.sh
Executable file
18
z1/start-app.sh
Executable file
@ -0,0 +1,18 @@
|
|||||||
|
#!/bin/bash
|
||||||
|
|
||||||
|
echo "Creating Namespace..."
|
||||||
|
kubectl apply -f k8s/namespace.yaml
|
||||||
|
|
||||||
|
echo "Creating Persistent Volumes and StatefulSet..."
|
||||||
|
kubectl apply -f k8s/statefulset.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deploying PostgreSQL..."
|
||||||
|
kubectl apply -f k8s/postgres-deployment.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deploying Flask App..."
|
||||||
|
kubectl apply -f k8s/deployment.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Creating Service..."
|
||||||
|
kubectl apply -f k8s/service.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "All resources have been applied."
|
18
z1/stop-app.sh
Executable file
18
z1/stop-app.sh
Executable file
@ -0,0 +1,18 @@
|
|||||||
|
#!/bin/bash
|
||||||
|
|
||||||
|
echo "Deleting Flask App Deployment..."
|
||||||
|
kubectl delete -f k8s/deployment.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deleting Flask Service..."
|
||||||
|
kubectl delete -f k8s/service.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deleting PostgreSQL Deployment and PVC..."
|
||||||
|
kubectl delete -f k8s/postgres-deployment.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deleting StatefulSet and PVs..."
|
||||||
|
kubectl delete -f k8s/statefulset.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deleting Namespace..."
|
||||||
|
kubectl delete -f k8s/namespace.yaml
|
||||||
|
|
||||||
|
echo "All resources have been deleted."
|
9
z2/Dockerfile
Normal file
9
z2/Dockerfile
Normal file
@ -0,0 +1,9 @@
|
|||||||
|
FROM python:3.9-slim
|
||||||
|
|
||||||
|
WORKDIR /app
|
||||||
|
|
||||||
|
COPY app/ .
|
||||||
|
|
||||||
|
RUN pip install --no-cache-dir -r requirements.txt
|
||||||
|
|
||||||
|
CMD ["python", "main.py"]
|
138
z2/README.md
Normal file
138
z2/README.md
Normal file
@ -0,0 +1,138 @@
|
|||||||
|
# Flask + PostgreSQL Kubernetes WebApp
|
||||||
|
|
||||||
|
A lightweight full-stack web application powered by **Flask** and **PostgreSQL**, containerized with **Docker**, and deployed on **Kubernetes (Minikube)** using custom `Namespace`, `Deployment`, `StatefulSet`, and `Services`. Designed to demonstrate a production-like cloud-native architecture.
|
||||||
|
|
||||||
|
---
|
||||||
|
|
||||||
|
## Project Structure
|
||||||
|
|
||||||
|
```bash
|
||||||
|
z2/
|
||||||
|
├── app/
|
||||||
|
│ ├── main.py # Flask application logic
|
||||||
|
│ └── requirements.txt # Python dependencies
|
||||||
|
├── k8s/
|
||||||
|
│ ├── namespace.yaml # Custom namespace
|
||||||
|
│ ├── deployment.yaml # Flask app deployment
|
||||||
|
│ ├── postgres-deployment.yaml # PostgreSQL StatefulSet + PVC + Service
|
||||||
|
│ ├── migrate-job.yaml # Migration job (optional)
|
||||||
|
│ ├── service.yaml # Flask NodePort Service
|
||||||
|
├── Dockerfile # For building Flask app image
|
||||||
|
├── prepare-app.sh # Script: Build & tag Docker image
|
||||||
|
├── start-app.sh # Script: Apply all Kubernetes configs
|
||||||
|
├── stop-app.sh # Script: Delete all resources
|
||||||
|
└── README.md # Project documentation
|
||||||
|
```
|
||||||
|
|
||||||
|
---
|
||||||
|
|
||||||
|
## How It Works
|
||||||
|
|
||||||
|
1. **Prepare the Environment**
|
||||||
|
```bash
|
||||||
|
./prepare-app.sh
|
||||||
|
```
|
||||||
|
- Builds and tags Docker image locally
|
||||||
|
- Prepares persistent volume (PVC) for PostgreSQL
|
||||||
|
|
||||||
|
2. **Deploy the Application**
|
||||||
|
```bash
|
||||||
|
./start-app.sh
|
||||||
|
```
|
||||||
|
- Creates namespace, StatefulSet, Deployments, Services
|
||||||
|
|
||||||
|
3. **Access the Web App**
|
||||||
|
```bash
|
||||||
|
minikube service flask-service -n webapp-namespace
|
||||||
|
```
|
||||||
|
- Opens the app in your browser (NodePort)
|
||||||
|
|
||||||
|
4. **Stop and Clean Everything**
|
||||||
|
```bash
|
||||||
|
./stop-app.sh
|
||||||
|
```
|
||||||
|
- Deletes all created Kubernetes resources
|
||||||
|
|
||||||
|
---
|
||||||
|
|
||||||
|
## Technologies Used
|
||||||
|
|
||||||
|
| Tool | Purpose |
|
||||||
|
|----------------|------------------------------|
|
||||||
|
| Flask | Web framework (Python) |
|
||||||
|
| PostgreSQL | Relational database |
|
||||||
|
| Docker | Containerization |
|
||||||
|
| Kubernetes | Container orchestration |
|
||||||
|
| Minikube | Local Kubernetes environment |
|
||||||
|
|
||||||
|
---
|
||||||
|
|
||||||
|
## Health Checks
|
||||||
|
|
||||||
|
To ensure resilience and uptime, Kubernetes probes can be added:
|
||||||
|
|
||||||
|
```yaml
|
||||||
|
livenessProbe:
|
||||||
|
httpGet:
|
||||||
|
path: /health
|
||||||
|
port: 8000
|
||||||
|
initialDelaySeconds: 5
|
||||||
|
periodSeconds: 10
|
||||||
|
|
||||||
|
readinessProbe:
|
||||||
|
httpGet:
|
||||||
|
path: /health
|
||||||
|
port: 8000
|
||||||
|
initialDelaySeconds: 5
|
||||||
|
periodSeconds: 10
|
||||||
|
```
|
||||||
|
|
||||||
|
Add a `/health` route to your `main.py`:
|
||||||
|
```python
|
||||||
|
@app.route('/health')
|
||||||
|
def health():
|
||||||
|
return "OK", 200
|
||||||
|
```
|
||||||
|
|
||||||
|
---
|
||||||
|
|
||||||
|
## Troubleshooting
|
||||||
|
|
||||||
|
| Problem | Solution |
|
||||||
|
|-------------------------------------|--------------------------------------------------------------------------|
|
||||||
|
| ❌ `ImagePullBackOff` or `ErrImagePull` | Make sure image is built locally with `docker build -t flask-app .` and you're using `imagePullPolicy: Never` |
|
||||||
|
| ❌ App not accessible | Check service type is `NodePort`, port 30080 is exposed, and run `minikube service flask-service -n webapp-namespace` |
|
||||||
|
| ❌ Database errors | Ensure PostgreSQL pod is running (`kubectl get pods -n webapp-namespace`), check PVC and env vars |
|
||||||
|
| ❌ "command not found: kubectl" | Install `kubectl` and make sure it’s configured with `minikube` context |
|
||||||
|
| ❌ Connection refused errors | Check that `POSTGRES_HOST` matches the service name (`postgres`) and app waits until DB is ready |
|
||||||
|
|
||||||
|
---
|
||||||
|
|
||||||
|
## Future Enhancements
|
||||||
|
|
||||||
|
- Use Helm for templated deployments
|
||||||
|
- Add database migrations (Alembic / Flask-Migrate)
|
||||||
|
- CI/CD integration with GitLab or GitHub Actions
|
||||||
|
- Add Redis or caching layer
|
||||||
|
- Auto-scaling and HorizontalPodAutoscaler
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
## Author
|
||||||
|
|
||||||
|
**Hafzal Ahamed Hasan Mohamed**
|
||||||
|
TUKE, Faculty of Electrical Engineering and Informatics
|
||||||
|
Git: [git.kemt.fei.tuke.sk/hh304ug/zkt25](https://git.kemt.fei.tuke.sk/hh304ug/zkt25)
|
||||||
|
|
||||||
|
|
||||||
|
hafzal03@LAPTOP-ELUS3HGM:~/mypro/z2$ kubectl get pods -n webapp-namespace
|
||||||
|
NAME READY STATUS RESTARTS AGE
|
||||||
|
flask-app-6b844bf6-cq9t6 1/1 Running 0 8m37s
|
||||||
|
postgres-644fc4c86d-l9h4f 1/1 Running 0 14m
|
||||||
|
hafzal03@LAPTOP-ELUS3HGM:~/mypro/z2$ minikube service flask-service -n webapp-namespace
|
||||||
|
|
||||||
|
minikube service flask-service -n webapp-namespace
|
||||||
|
|
||||||
|
kubectl get pods -n webapp-namespace
|
||||||
|
|
||||||
|
kubectl rollout restart deployment flask-app -n webapp-namespace
|
81
z2/app/main.py
Normal file
81
z2/app/main.py
Normal file
@ -0,0 +1,81 @@
|
|||||||
|
from flask import Flask, request, jsonify, render_template_string
|
||||||
|
import psycopg2
|
||||||
|
import os
|
||||||
|
|
||||||
|
app = Flask(__name__)
|
||||||
|
|
||||||
|
def get_db_connection():
|
||||||
|
return psycopg2.connect(
|
||||||
|
host=os.environ.get("POSTGRES_HOST"),
|
||||||
|
database=os.environ.get("POSTGRES_DB"),
|
||||||
|
user=os.environ.get("POSTGRES_USER"),
|
||||||
|
password=os.environ.get("POSTGRES_PASSWORD"),
|
||||||
|
port=os.environ.get("POSTGRES_PORT", 5432),
|
||||||
|
)
|
||||||
|
|
||||||
|
def init_db():
|
||||||
|
conn = get_db_connection()
|
||||||
|
cur = conn.cursor()
|
||||||
|
cur.execute("""
|
||||||
|
CREATE TABLE IF NOT EXISTS students (
|
||||||
|
id SERIAL PRIMARY KEY,
|
||||||
|
name TEXT NOT NULL,
|
||||||
|
room_number TEXT NOT NULL,
|
||||||
|
faculty TEXT NOT NULL
|
||||||
|
);
|
||||||
|
""")
|
||||||
|
conn.commit()
|
||||||
|
cur.close()
|
||||||
|
conn.close()
|
||||||
|
|
||||||
|
@app.route("/")
|
||||||
|
def index():
|
||||||
|
return "<h1>Welcome!</h1><p>Go to /add to add a student, /students to view all.</p>"
|
||||||
|
|
||||||
|
# HTML Form + POST Submission
|
||||||
|
@app.route("/add", methods=["GET", "POST"])
|
||||||
|
def add_student():
|
||||||
|
if request.method == "POST":
|
||||||
|
name = request.form.get("name")
|
||||||
|
room_number = request.form.get("room_number")
|
||||||
|
faculty = request.form.get("faculty")
|
||||||
|
|
||||||
|
if not name or not room_number or not faculty:
|
||||||
|
return "All fields are required!", 400
|
||||||
|
|
||||||
|
conn = get_db_connection()
|
||||||
|
cur = conn.cursor()
|
||||||
|
cur.execute("INSERT INTO students (name, room_number, faculty) VALUES (%s, %s, %s)", (name, room_number, faculty))
|
||||||
|
conn.commit()
|
||||||
|
cur.close()
|
||||||
|
conn.close()
|
||||||
|
return "<p>Student added successfully!</p><a href='/add'>Add another</a>"
|
||||||
|
|
||||||
|
# HTML form
|
||||||
|
return render_template_string("""
|
||||||
|
<h2>Add Student</h2>
|
||||||
|
<form method="post">
|
||||||
|
Name: <input name="name"><br>
|
||||||
|
Room Number: <input name="room_number"><br>
|
||||||
|
Faculty: <input name="faculty"><br>
|
||||||
|
<input type="submit" value="Add Student">
|
||||||
|
</form>
|
||||||
|
""")
|
||||||
|
|
||||||
|
# View all students
|
||||||
|
@app.route("/students", methods=["GET"])
|
||||||
|
def get_students():
|
||||||
|
conn = get_db_connection()
|
||||||
|
cur = conn.cursor()
|
||||||
|
cur.execute("SELECT id, name, room_number, faculty FROM students")
|
||||||
|
rows = cur.fetchall()
|
||||||
|
cur.close()
|
||||||
|
conn.close()
|
||||||
|
|
||||||
|
return jsonify([
|
||||||
|
{"id": row[0], "name": row[1], "room_number": row[2], "faculty": row[3]} for row in rows
|
||||||
|
])
|
||||||
|
|
||||||
|
if __name__ == "__main__":
|
||||||
|
init_db()
|
||||||
|
app.run(host="0.0.0.0", port=8000)
|
5
z2/app/requirements.txt
Normal file
5
z2/app/requirements.txt
Normal file
@ -0,0 +1,5 @@
|
|||||||
|
Flask==2.0.1
|
||||||
|
Werkzeug==2.0.3
|
||||||
|
psycopg2-binary==2.9.1
|
||||||
|
python-dotenv==0.19.0
|
||||||
|
Jinja2==3.0.3
|
32
z2/k8s/deployment.yaml
Normal file
32
z2/k8s/deployment.yaml
Normal file
@ -0,0 +1,32 @@
|
|||||||
|
apiVersion: apps/v1
|
||||||
|
kind: Deployment
|
||||||
|
metadata:
|
||||||
|
name: flask-app
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
replicas: 1
|
||||||
|
selector:
|
||||||
|
matchLabels:
|
||||||
|
app: flask
|
||||||
|
template:
|
||||||
|
metadata:
|
||||||
|
labels:
|
||||||
|
app: flask
|
||||||
|
spec:
|
||||||
|
containers:
|
||||||
|
- name: flask
|
||||||
|
image: flask-app:latest
|
||||||
|
imagePullPolicy: Never
|
||||||
|
ports:
|
||||||
|
- containerPort: 8000
|
||||||
|
env:
|
||||||
|
- name: POSTGRES_HOST
|
||||||
|
value: postgres
|
||||||
|
- name: POSTGRES_DB
|
||||||
|
value: mydatabase
|
||||||
|
- name: POSTGRES_USER
|
||||||
|
value: myuser
|
||||||
|
- name: POSTGRES_PASSWORD
|
||||||
|
value: mypassword
|
||||||
|
- name: POSTGRES_PORT
|
||||||
|
value: "5432"
|
12
z2/k8s/migrate-job.yaml
Normal file
12
z2/k8s/migrate-job.yaml
Normal file
@ -0,0 +1,12 @@
|
|||||||
|
apiVersion: batch/v1
|
||||||
|
kind: Job
|
||||||
|
metadata:
|
||||||
|
name: migrate
|
||||||
|
spec:
|
||||||
|
template:
|
||||||
|
spec:
|
||||||
|
containers:
|
||||||
|
- name: migrator
|
||||||
|
image: myapp:latest
|
||||||
|
command: ["python", "manage.py", "migrate"]
|
||||||
|
restartPolicy: Never
|
4
z2/k8s/namespace.yaml
Normal file
4
z2/k8s/namespace.yaml
Normal file
@ -0,0 +1,4 @@
|
|||||||
|
apiVersion: v1
|
||||||
|
kind: Namespace
|
||||||
|
metadata:
|
||||||
|
name: webapp-namespace
|
57
z2/k8s/postgres-deployment.yaml
Normal file
57
z2/k8s/postgres-deployment.yaml
Normal file
@ -0,0 +1,57 @@
|
|||||||
|
apiVersion: v1
|
||||||
|
kind: PersistentVolumeClaim
|
||||||
|
metadata:
|
||||||
|
name: postgres-pvc
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
accessModes:
|
||||||
|
- ReadWriteOnce
|
||||||
|
resources:
|
||||||
|
requests:
|
||||||
|
storage: 1Gi
|
||||||
|
---
|
||||||
|
apiVersion: apps/v1
|
||||||
|
kind: Deployment
|
||||||
|
metadata:
|
||||||
|
name: postgres
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
replicas: 1
|
||||||
|
selector:
|
||||||
|
matchLabels:
|
||||||
|
app: postgres
|
||||||
|
template:
|
||||||
|
metadata:
|
||||||
|
labels:
|
||||||
|
app: postgres
|
||||||
|
spec:
|
||||||
|
containers:
|
||||||
|
- name: postgres
|
||||||
|
image: postgres:13
|
||||||
|
env:
|
||||||
|
- name: POSTGRES_DB
|
||||||
|
value: mydatabase
|
||||||
|
- name: POSTGRES_USER
|
||||||
|
value: myuser
|
||||||
|
- name: POSTGRES_PASSWORD
|
||||||
|
value: mypassword
|
||||||
|
ports:
|
||||||
|
- containerPort: 5432
|
||||||
|
volumeMounts:
|
||||||
|
- name: postgres-storage
|
||||||
|
mountPath: /var/lib/postgresql/data
|
||||||
|
volumes:
|
||||||
|
- name: postgres-storage
|
||||||
|
persistentVolumeClaim:
|
||||||
|
claimName: postgres-pvc
|
||||||
|
---
|
||||||
|
apiVersion: v1
|
||||||
|
kind: Service
|
||||||
|
metadata:
|
||||||
|
name: postgres
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
selector:
|
||||||
|
app: postgres
|
||||||
|
ports:
|
||||||
|
- port: 5432
|
13
z2/k8s/service.yaml
Normal file
13
z2/k8s/service.yaml
Normal file
@ -0,0 +1,13 @@
|
|||||||
|
apiVersion: v1
|
||||||
|
kind: Service
|
||||||
|
metadata:
|
||||||
|
name: flask-service
|
||||||
|
namespace: webapp-namespace
|
||||||
|
spec:
|
||||||
|
selector:
|
||||||
|
app: flask
|
||||||
|
type: NodePort
|
||||||
|
ports:
|
||||||
|
- port: 8000
|
||||||
|
targetPort: 8000
|
||||||
|
nodePort: 30080 # <-- Changed this
|
10
z2/prepare-app.sh
Executable file
10
z2/prepare-app.sh
Executable file
@ -0,0 +1,10 @@
|
|||||||
|
#!/bin/bash
|
||||||
|
|
||||||
|
echo "Building Docker image for Flask app..."
|
||||||
|
docker build -t flask-app:latest .
|
||||||
|
|
||||||
|
echo "Creating Minikube image cache (if using Minikube)..."
|
||||||
|
eval $(minikube docker-env)
|
||||||
|
docker build -t flask-app:latest .
|
||||||
|
|
||||||
|
echo "Preparation complete."
|
18
z2/start-app.sh
Executable file
18
z2/start-app.sh
Executable file
@ -0,0 +1,18 @@
|
|||||||
|
#!/bin/bash
|
||||||
|
|
||||||
|
echo "Creating Namespace..."
|
||||||
|
kubectl apply -f k8s/namespace.yaml
|
||||||
|
|
||||||
|
echo "Creating Persistent Volumes and StatefulSet..."
|
||||||
|
kubectl apply -f k8s/statefulset.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deploying PostgreSQL..."
|
||||||
|
kubectl apply -f k8s/postgres-deployment.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deploying Flask App..."
|
||||||
|
kubectl apply -f k8s/deployment.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Creating Service..."
|
||||||
|
kubectl apply -f k8s/service.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "All resources have been applied."
|
18
z2/stop-app.sh
Executable file
18
z2/stop-app.sh
Executable file
@ -0,0 +1,18 @@
|
|||||||
|
#!/bin/bash
|
||||||
|
|
||||||
|
echo "Deleting Flask App Deployment..."
|
||||||
|
kubectl delete -f k8s/deployment.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deleting Flask Service..."
|
||||||
|
kubectl delete -f k8s/service.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deleting PostgreSQL Deployment and PVC..."
|
||||||
|
kubectl delete -f k8s/postgres-deployment.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deleting StatefulSet and PVs..."
|
||||||
|
kubectl delete -f k8s/statefulset.yaml -n webapp-namespace
|
||||||
|
|
||||||
|
echo "Deleting Namespace..."
|
||||||
|
kubectl delete -f k8s/namespace.yaml
|
||||||
|
|
||||||
|
echo "All resources have been deleted."
|
Loading…
Reference in New Issue
Block a user