app.py

from flask import Flask, render_template, request, redirect, url_for
from flask_mysqldb import MySQL
import os

app = Flask(__name__)

# Configure MySQL
app.config['MYSQL_HOST'] = os.environ.get("MYSQL_HOST", "localhost")
app.config['MYSQL_USER'] = os.environ.get("MYSQL_USER", "user")
app.config['MYSQL_PASSWORD'] = os.environ.get("MYSQL_PASSWORD", "")
app.config['MYSQL_DB'] = os.environ.get("MYSQL_DB", "flask_example")
app.config['MYSQL_CURSORCLASS'] = 'DictCursor'

mysql = MySQL(app)

@app.route('/')
def index():
    return render_template('index.html')

@app.route('/greet', methods=['POST'])
def greet():
    name = request.form['name']
    age = request.form['age']

    cur = mysql.connection.cursor()
    
    # Using parameterized query to prevent SQL injection
    query = 'INSERT INTO user (name, age) VALUES (%s, %s)'
    values = (name, age)
    cur.execute(query, values)
    
    mysql.connection.commit()
    
    # Fetch data to display in the greeting.html template
    cur.execute('SELECT * FROM user')
    data = cur.fetchall()
    cur.close()

    return render_template('greeting.html', data=data)

if __name__ == '__main__':
    app.run(debug=True, host="0.0.0.0")