@app.route('/login', methods=('GET', 'POST'))
def login():
    form = LoginForm(request.form)
    if form.validate_on_submit():

        user = User.query.filter_by(email=form.email.data).first()
        if user and check_password_hash(user.password, form.password.data):
            session['user.id'] = user.id
            flash('Welcome %s' % user.username)
            return redirect(url_for('index'))
    return render_template("login.html", form=form)

class User(UserMixin,db.Model):
    id = db.Column(db.Integer, primary_key = True, autoincrement=True)
    username = db.Column(db.String(64), index = True, unique = True)
    email = db.Column(db.String(120), index = True, unique = True)
    password = db.Column(db.String(120), index = True)
    role = db.Column(db.SmallInteger, default=ROLE_USER)

    def __init__(self, id, username, email, password, role):
        self.id = id
        self.username = username
        self.password = password
        self.email = email
        self.role = role

def set_password(self, password):
    self.pw_hash = generate_password_hash(password)

def check_password(self, password):
    return check_password_hash(self.pw_hash, password)