class User(db.Model):

id = db.Column(db.Integer, primary_key=True)

username = db.Column(db.String(64), index=True, unique=True)

password_hash = db.Column(db.String(128))

role = db.Column(db.String(10)) # student, teacher, admin

]]>

@app.route('/login', methods=['POST'])

def login():

data = request.get_json()

user = User.query.filter_by(username=data['username']).first()

if user and check_password_hash(user.password_hash, data['password']):

token = create_access_token(identity=user.id)

return jsonify(access_token=token), 200

else:

return jsonify(error="Invalid credentials"), 401

]]>