app.py

from flask import Flask, render_template, request, redirect, session, flash
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime
from werkzeug.security import generate_password_hash, check_password_hash

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///blog.db'
app.config['SECRET_KEY'] = "The Dev Journal"
db = SQLAlchemy(app)

class User(db.Model):
    id = db.Column(db.Integer, primary_key = True)
    username = db.Column(db.String(255), unique = True, nullable = False)
    password = db.Column(db.String(255), nullable = False)

class Blog(db.Model):
    id = db.Column(db.Integer, primary_key = True)
    title = db.Column(db.String(100), nullable = False)
    description = db.Column(db.Text, nullable = False)
    created_at = db.Column(db.DateTime, default = datetime.utcnow)
    author = db.Column(db.String(255), nullable=False)

with app.app_context():
    db.create_all()

@app.route('/')
def home():
    all_blogs = Blog.query.all()
    return render_template('index.html', all_blogs = all_blogs)

@app.route('/profile')
def profile():
    if 'user' not in session:
        return redirect('/login')
    user_blogs = Blog.query.filter_by(author=session['user']).all()
    return render_template('profile.html', blogs=user_blogs)

@app.route('/register', methods = ['POST', 'GET'])
def register():
    if request.method == 'POST':
        username = request.form.get('username')
        password = request.form.get('password')
        new_password = generate_password_hash(password=password)
        user = User.query.filter_by(username = username).first()
        if not user:
            new_user = User(username = username, password = new_password)
            db.session.add(new_user)
            db.session.commit()
            flash('Registration successful! Please login.', 'success')
            return redirect('/login')
    return render_template('register.html')

@app.route('/login', methods = ['POST', 'GET'])
def login():
    if request.method == 'POST':
        username = request.form.get('username')
        password = request.form.get('password')
        user = User.query.filter_by(username = username).first()
        if user and check_password_hash(user.password , password):
            session['user'] = username
            flash('Login Successful!', 'success')
            return redirect('/')
        flash('Wrong Username Or Password', 'danger')
    return render_template('login.html')

@app.route('/logout')
def logout():
    session.pop('user')
    flash('Logout Successful!', 'info')
    return redirect('/')

@app.route('/create-blog', methods = ['POST', 'GET'])
def create_blog():
    if request.method == 'POST':
        title = request.form.get('title')
        description = request.form.get('description')
        new_blog = Blog(title = title, description = description, author = session['user'])
        db.session.add(new_blog)
        db.session.commit()
        flash('Post created successfully!', 'success')
        return redirect('/')
    return render_template('create_blog.html')

@app.route("/blog/<int:id>")
def blog_detail(id):
    blog = Blog.query.filter_by(id=id).first()
    return render_template('blog.html', blog=blog)

@app.route('/delete/<int:id>')
def blog_delete(id):
    blog = Blog.query.filter_by(id=id).first()
    if not 'user' in session:
        return redirect('/login')
    if not blog.author == session['user']:
        return redirect('/')
    db.session.delete(blog)
    db.session.commit()
    return redirect('/')

@app.route('/update/<int:id>', methods = ['POST', 'GET'])
def update_blog(id):
    blog = Blog.query.filter_by(id=id).first()
    if not 'user' in session:
        return redirect('/login')
    if not blog.author == session['user']:
        return redirect('/')
    if request.method == "POST":
        title = request.form.get('title')
        description = request.form.get('description')
        blog.title = title
        blog.description = description
        db.session.add(blog)
        db.session.commit()
        return redirect('/')
    return render_template('update_blog.html', blog=blog)

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