Foundations of Python Network Programming

Chapter 11 ■ the World Wide Web

193

app = Flask(name)
get = Environment(loader=PackageLoader(name, 'templates')).get_template

@app.route('/login', methods=['GET', 'POST'])
def login():
username = request.form.get('username', '')
password = request.form.get('password', '')
if request.method == 'POST':
if (username, password) in [('brandon', 'atigdng'), ('sam', 'xyzzy')]:
response = redirect(url_for('index'))
response.set_cookie('username', username)
return response
return get('login.html').render(username=username)

@app.route('/logout')
def logout():
response = redirect(url_for('login'))
response.set_cookie('username', '')
return response

@app.route('/')
def index():
username = request.cookies.get('username')
if not username:
return redirect(url_for('login'))
payments = bank.get_payments_of(bank.open_database(), username)
return get('index.html').render(payments=payments, username=username,
flash_messages=request.args.getlist('flash'))

@app.route('/pay', methods=['GET', 'POST'])
def pay():
username = request.cookies.get('username')
if not username:
return redirect(url_for('login'))
account = request.form.get('account', '').strip()
dollars = request.form.get('dollars', '').strip()
memo = request.form.get('memo', '').strip()
complaint = None
if request.method == 'POST':
if account and dollars and dollars.isdigit() and memo:
db = bank.open_database()
bank.add_payment(db, username, account, dollars, memo)
db.commit()
return redirect(url_for('index', flash='Payment successful'))
complaint = ('Dollars must be an integer' if not dollars.isdigit()
else 'Please fill in all three fields')
return get('pay.html').render(complaint=complaint, account=account,
dollars=dollars, memo=memo)

if name == 'main':
app.debug = True
app.run()