flask auth

auth.py

import os
from flask import Flask, request, session, url_for, redirect, \
     render_template, abort, g, flash
from flask_bcrypt import Bcrypt



app = Flask(__name__)
bcrypt = Bcrypt(app)
app.config.from_object(os.environ['APP_SETTINGS'])



# Controllers    
@app.before_request
def before_request():
  g.admin = None
  if 'admin_id' in session:
    g.admin = Admin.query.filter_by(id=session['admin_id']).first()


@app.route("/")
def hello():
    return "Hello World!"



# Admin

@app.route('/admin')
def admin():
  if g.admin is not None:
    return render_template('admin.html', error="Admin is not logged in")
  else:
    return redirect(url_for('login'))

# Users

@app.route('/login', methods=['GET', 'POST'])
def login():
  if g.admin:
    return redirect(url_for('admin'))
  
  error = None
  
  if request.method == 'POST':
    admin = Admin.query.filter_by(username=request.form['username']).first()
    if admin is None:
        error = 'Invalid username'
    elif not bcrypt.check_password_hash(admin.pw_hash, request.form['password']):
      error = 'Invalid password'
    else:
      flash('You were logged in')
      session['admin_id'] = admin.id
      return redirect(url_for('admin'))
  
  return render_template('login.html', error=error)


@app.route('/register', methods=['GET', 'POST'])
def register():
    if g.admin:
        return redirect(url_for('admin'))
    
    error = None
    
    if request.method == 'POST':
      if not request.form['username']:
        error = 'You have to enter a username'
      elif not request.form['email'] or '@' not in request.form['email']:
        error = 'You have to enter a valid email address'
      elif not request.form['password']:
        error = 'You have to enter a password'
      elif request.form['password'] != request.form['password2']:
        error = 'The two passwords do not match'
      elif Admin.query.filter_by(username=request.form['username']).first() is not None:
        error = 'The username is already taken'
      else:
        admin = Admin(request.form['username'], request.form['email'], bcrypt.generate_password_hash(request.form['password']).decode('utf-8'))
        db.session.add(admin)
        db.session.commit()
        flash('You were successfully registered, an existing admin will need to approve you before you can login.')
        return redirect(url_for('login'))
    
    return render_template('register.html', error=error)


@app.route('/logout')
def logout():
  flash('You were logged out')
  session.pop('admin_id', None)
  return redirect('/')