udacity hw 5

homework 5

import webapp2
import re
import os
import jinja2
import re
import hashlib
import hmac
import random
import string
from google.appengine.ext import db
import json


secret = 'imsosecret'

template_dir = os.path.join(os.path.dirname(__file__), 'templates')
jinja_env = jinja2.Environment(loader = jinja2.FileSystemLoader(template_dir),
  							autoescape = True)

USER_RE = re.compile(r"^[a-zA-Z0-9_-]{3,20}$")
PASS_RE = re.compile(r"^.{3,20}$")
EMAIL_RE = re.compile(r"^[\S]+@[\S]+\.[\S]+$")


class User(db.Model):
	username = db.StringProperty()
	password_hash = db.StringProperty()
	email = db.StringProperty()
	hashish = db.StringProperty()
	subject = db.StringProperty()
	content = db.TextProperty()
	created = db.DateTimeProperty(auto_now_add = True)
														
def valid_username(username):
	return USER_RE.match(username)

def valid_password(password):
	return PASS_RE.match(password)
	
def valid_email(email):
	return EMAIL_RE.match(email)


def make_salt():
	return ''.join(random.choice(string.letters) for x in xrange(5))
	
def make_pw_hash(name, pw, salt=None):
	if not salt:
		salt = make_salt()
	h = hashlib.sha256(name + pw + salt).hexdigest()

	return '%s,%s' % (h, salt)

def valid_pw(name, pw, h):
	print h, "h"
	old_salt = h.split(',')[1]
	
	return h == make_pw_hash(name, pw, old_salt)


def hash_str(s):
	return hmac.new(secret, s).hexdigest()
	
def make_secure_val(s):
	return "%s|%s" % (s, hash_str(s))	

def check_secure_val(h):
	val = h.split('|')[0]
	if h == make_secure_val(val):
		return val
	
class Handler(webapp2.RequestHandler):
	def write(self, *a, **kw):
		self.response.out.write(*a, **kw)
		
	def render_str(self, template, **params):
		t = jinja_env.get_template(template)
		return t.render(params)
		
	def render(self, template, **kw):
		self.write(self.render_str(template, **kw))

		
class MainPage(Handler):
	def render_front(self, username="", email="", error=""):
		self.render("front.html", username=username, email=email, error=error)
		
	def get(self):
		self.response.headers['Content-Type'] = 'text/html'
		
		self.render_front()

		self.redirect('/signup')
		
class SignUpPage(Handler):
	def render_newfront(self, username="", email="", error=""):
		self.render("front.html", username=username, email=email, error=error)
	
	def get(self):
		self.response.headers['Content-Type'] = 'text/html'
		
		self.render_newfront()
		
	def post(self):
		
		username = self.request.get("username")
		password = self.request.get("password")
		verify = self.request.get("verify")
		email = self.request.get("email")
				
		v_username = valid_username(username)
		v_password = valid_password(password)
		v_email = valid_email(email)
		
		error = ''
		valid = False
		
		if not v_username:
			error = "That is not a valid Username"
			self.render_newfront(username, email, error)
		elif not v_password:
			error = "That is not a valid Password."
			self.render_newfront(username, email, error)
		elif password != verify:
			error = "Your Password does not match the Verify Password."
			self.render_newfront(username, email, error)
		elif email == "":
			email = "None"
			valid = True
		elif not v_email:
			error = "Your email is lacking validation capacity!"
			self.render_newfront(username, email, error)
		else:
			valid = True

		if valid == True:
						
			users = User.all()
			
			old_user = False
			
			for p in users:
				print p.username
				if p.username == username:
					old_user = True
			if old_user == 	True:
				error = "That user already exists."
				self.render_newfront('', '', error)
				
			else:
				user_id = None
				user_id_cookie_str = self.request.cookies.get('user_id')

				if user_id_cookie_str:
					cookie_val = check_secure_val(user_id_cookie_str)
					if cookie_val:
						user_id = str(cookie_val)
					self.redirect("/welcome")
				else:
					self.render_newfront()
			
				hashish = None
			
				pw_hashish_salt = make_pw_hash(username, password, hashish)
				password_hash = pw_hashish_salt.split(',')[0]
				hashish = pw_hashish_salt.split(',')[1]
				a = User(username = username, password_hash = password_hash, hashish = hashish, email = email)
				a_key = a.put()
				
				new_cookie_val = make_secure_val(str(a_key.id()))
				
				self.response.headers.add_header('Set-Cookie', 'user_id=%s; Path=/' % new_cookie_val)
				
				self.redirect('/welcome')

class LoginPage(Handler):
	def render_newfront(self, username="", error=""):
		self.render("login.html", username=username, error=error)
	
	def get(self):
		self.response.headers['Content-Type'] = 'text/html'
		
		self.render_newfront()
		
	def post(self):
		
		username = self.request.get("username")
		password = self.request.get("password")
				
		v_username = valid_username(username)
		v_password = valid_password(password)
		
		error = ''
		valid = False
		
		if not v_username:
			error = "That is not a valid Username"
			self.render_newfront(username, error)
		elif not v_password:
			error = "That is not a valid Password."
			self.render_newfront(username, error)
		else:
			valid = True

		if valid == True:
						
			users = User.all()
			
			old_user = False
			
			for p in users:
				print p.username
				if p.username == username:
					old_user = True
					
			if old_user == 	True:
				error = "That user already exists."
				self.render_newfront('', error)
				
			else:
				user_id = None
				user_id_cookie_str = self.request.cookies.get('user_id')
				print user_id_cookie_str, "cookie str"
				if user_id_cookie_str:
					cookie_val = check_secure_val(user_id_cookie_str)
					if cookie_val:
						user_id = str(cookie_val)
					self.redirect("/welcome")
				else:
					self.render_newfront()
			
				hashish = None
			
				pw_hashish_salt = make_pw_hash(username, password, hashish)
				password_hash = pw_hashish_salt.split(',')[0]
				hashish = pw_hashish_salt.split(',')[1]
				a = User(username = username, password_hash = password_hash, hashish = hashish)
				a_key = a.put()
				
				new_cookie_val = make_secure_val(str(a_key.id()))
				print new_cookie_val, "new_cookie_val"
				
				self.response.headers.add_header('Set-Cookie', 'user_id=%s; Path=/' % new_cookie_val)
				
				self.redirect('/blog')
				
class Blog(Handler):
	def render_blogpage(self, subject="", content="", error=""):
		blogs=db.GqlQuery("SELECT * FROM User ORDER By created Desc")
		blogs = list(blogs)
		self.render("blog.html", subject=subject, content=content, error=error, blogs=blogs)
		
	def get(self):
		
		self.render_blogpage()
	
class JsonBlog(Handler):
	def get(self):
		blogs=db.GqlQuery("SELECT * FROM User ORDER By created Desc limit 10")
		timeformat = '%a %b %d %H:%M:%S %y'
		pythondict = [{"subject": p.subject,
					"content":p.content,
					"created":p.created.strftime(timeformat)}
					for p in blogs]
		jsonString = json.dumps(pythondict)
		
		self.response.headers['Content-Type'] = 'application/json; charset=UTF-8'
			
		self.response.out.write(jsonString)
		
class Json(Handler):
	def get(self):
		blogs=db.GqlQuery("SELECT * FROM User ORDER By created Desc limit 10")
		timeformat = '%a %b %d %H:%M:%S %y'
		pythondict = [{"subject": p.subject,
					"content":p.content,
					"created":p.created.strftime(timeformat)}
					for p in blogs]
		jsonString = json.dumps(pythondict)
		
		self.response.headers['Content-Type'] = 'application/json; charset=UTF-8'
			
		self.response.out.write(jsonString)
		
class PostPage(Handler):
	def render_postpage(self, subject="", content="", error=""):
		blogs=db.GqlQuery("SELECT * FROM User ORDER By created Desc")
		blogs = list(blogs)
		self.render("newpost.html", subject=subject, content=content, error=error, blogs=blogs)
		
	def get(self):
		self.render_postpage()
		
	def post(self):
		subject = self.request.get("subject")
		content = self.request.get("content")
		
		if subject and content:
			post = User(subject = subject, content = content)
			post.put()
			
			self.redirect("/newpost/%s" % post.key().id())
			
		else:
			error = "We need both a subject and your content!"
			self.render_postpage(subject, content, error)				

class LatestPost(Handler):
		
	def get(self, post_id):
		post=User.get_by_id(int(post_id))
		self.render("latestpost.html", post=post)
			
class WelcomePost(Handler):
	def render_welcome_post(self, username=""):
		self.render("welcome.html", username=username)

	def get(self):
		user_id_cookie_str = self.request.cookies.get('user_id')
		print user_id_cookie_str
		if user_id_cookie_str:
			cookie_val = check_secure_val(user_id_cookie_str)
			if cookie_val:
				user_id = str(cookie_val)
				user = User.get_by_id(int(user_id.split('|')[0]))
				username = user.username			
				self.render('welcome.html', username = username)
		else:
			self.redirect('/signup')
			
class LogOutPage(Handler):
		
	def get(self):
		new_cookie_val = ""
		self.response.headers.add_header('Set-Cookie', 'user_id=%s; Path=/' % new_cookie_val)
		
		self.redirect('/signup')
		
				
app = webapp2.WSGIApplication([('/', MainPage), ('.json', Json), ('/.json', JsonBlog), ('/blog', Blog), ('/blog.json', JsonBlog), ('/newpost', PostPage), ('/newpost/(\d+)', LatestPost), ('/signup', SignUpPage),('/welcome', WelcomePost), ('/login', LoginPage), ('/logout', LogOutPage)], debug = True)