gistfile1.py

import webapp2
import re


class MainPage(webapp2.RequestHandler):
    with open('login.html', 'rU') as f:
        html = f.read()
    data = {'username':'',
            'password':'',
            'verify':'',
            'email':'',
            'usererror':'',
            'passerror':'',
            'verifyerror':'',
            'emailerror':''}
    def write_form(self, **kwargs):
        self.response.write(self.html % kwargs)
    def check_user(self, user):
        userRE = re.compile('^[a-zA-Z0-9_-]{3,20}$')
        if userRE.match(user):
            return user
    def check_password(self, password):
        passRE = re.compile('^.{3,20}$')
        if passRE.match(password):
            return password
    def check_email(self, email):
        emailRE = re.compile('^[\S]+@[\S]+\.[\S]+$')
        if emailRE.match(email):
            return email
    def verify_passwords(self, pass1, pass2):
        if pass1 == pass2:
            return True

    def get(self):
        self.write_form(**self.data)
    def post(self):
        user_username = self.request.get('username')
        user_password = self.request.get('password')
        user_verify = self.request.get('verify')
        user_email = self.request.get('email')
        username = self.check_user(user_username)
        password = self.check_password(user_password)
        verify = self.verify_passwords(user_password, user_verify)
        email = self.check_email(user_email)

        if(username and password and verify and email):
            print 'awesome'
        else:
            if not username:
                self.data['usererror'] = "Username is not correct"
            if not password:
                self.data['passerror'] = "Password is not 3-20 chars long"
            if not verify:
                self.data['verifyerror'] = "Passwords do not match"
            if not email:
                self.data['emailerror'] = "Email address is not [email protected]"
            self.data['username'] = user_username
            self.data['password'] = user_password
            self.data['verify'] = user_verify
            self.data['email'] = user_email
            self.write_form(**self.data)

app = webapp2.WSGIApplication([('/', MainPage)],
                              debug=True)