app.py

from flask import Flask , render_template ,request , redirect
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime

app = Flask(__name__)
app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///todo.db"
app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False

db = SQLAlchemy(app)

class Todo(db.Model ):
    sno = db.Column(db.Integer ,primary_key = True )
    title = db.Column(db.String(200) ,nullable = False )
    desc = db.Column(db.String(600) ,nullable = False )
    date_created = db.Column(db.DateTime , default = datetime.utcnow )

    def __repr__(self) -> str:
        return f"{self.sno} - {self.title}"

@app.route('/' , methods=['GET' , 'POST'])
def hello_world():
    if request.method == 'POST':
        title = request.form['title']
        desc = request.form['desc']
        todo = Todo(title =title, desc = desc) 
        db.session.add(todo)
        db.session.commit()

    alltodo = Todo.query.all()
    return render_template("index.html", alltodo = alltodo)

@app.route('/delete/<int:sno>')
def delete(sno):
    todo = Todo.query.filter_by(sno=sno).first()
    db.session.delete(todo)
    db.session.commit()

    return redirect("/")

@app.route('/edit/<int:sno>' , methods=['GET' , 'POST'])
def edit(sno):
    if request.method == 'POST':
        title = request.form['title']
        desc = request.form['desc']
        todo = Todo.query.filter_by(sno=sno).first() 
        todo.title = title
        todo.desc = desc
        db.session.add(todo)
        db.session.commit()
        
        return redirect('/')

    todo = Todo.query.filter_by(sno=sno).first()
    return render_template('update.html', todo=todo)


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


if __name__ == "__main__":
    app.run(debug=True ,port=8000)