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|
"""Authentication blueprint"""
import functools
from flask import (
Blueprint, flash, g, redirect, render_template, request, session, url_for
)
from werkzeug.security import check_password_hash, generate_password_hash
from flaskr.db import get_db
bp = Blueprint('auth', __name__, url_prefix='/auth')
@bp.route('/register', methods=('GET', 'POST'))
def register():
if request.method == 'POST':
# Form validation
username = request.form['username']
password = request.form['password']
db = get_db()
error = None
if not username:
error = 'Username is required.'
elif not password:
error = 'Password is required.'
if error is None:
try:
# NOTE: don't use f-string here. Use `?` placeholders so that
# database library can escape the fields
# (otherwise SQL injection vulnerability)
db.execute(
"INSERT INTO user (username, password) VALUES (?, ?)",
(username, generate_password_hash(password)),
)
db.commit()
except db.IntegrityError:
error = f"User {username} is already registered."
else:
return redirect(url_for("auth.login"))
flash(error)
return render_template('auth/register.html')
@bp.route('/login', methods=('GET', 'POST'))
def login():
if request.method == 'POST':
username = request.form['username']
password = request.form['password']
db = get_db()
error = None
user = db.execute(
'SELECT * FROM user WHERE username = ?', (username,)
).fetchone()
if user is None:
error = 'Incorrect username.'
elif not check_password_hash(user['password'], password):
error = 'Incorrect password.'
if error is None:
session.clear()
session['user_id'] = user['id']
return redirect(url_for('index'))
flash(error)
return render_template('auth/login.html')
# runs before the view function, no matter what URL is requested
@bp.before_app_request
def load_logged_in_user():
user_id = session.get('user_id')
if user_id is None:
g.user = None
else:
g.user = get_db().execute(
'SELECT * FROM user WHERE id = ?', (user_id,)
).fetchone()
@bp.route('/logout')
def logout():
session.clear()
return redirect(url_for('index'))
# Define decorator to require authentication in other views
def login_required(view):
"""view is a function that returns HTML (and is part of a blueprint)"""
@functools.wraps(view)
def wrapped_view(**kwargs):
if g.user is None:
return redirect(url_for('auth.login'))
return view(**kwargs)
return wrapped_view
|
