app.py

#import Flask class from flask module 

from flask import Flask, render_template, redirect, \
    url_for, request, session, flash
from functools import wraps
from flask.ext.sqlalchemy import SQLAlchemy


#creating the application object
app = Flask(__name__)

#config 

import os
app.config.from_object(os.environ['APP_SETTINGS'])



#create the sqlalchemy
db = SQLAlchemy(app)

#import db schema
from models import *

# login required decorator

def login_required(f):
    @wraps(f)
    def wrap(*args, **kwargs):
        if 'logged_in' in session:
            return f(*args, **kwargs)
        else:
            flash('You need to login first.')
            return redirect(url_for('log'))
    return wrap

#use decorators to link the function to a url  
@app.route('/')
@login_required
def home():
    posts = db.session.query(BlogPost).all()

    return render_template('home.html',posts=posts)    
     #render template,assigning  var posts => post and acess to that variable within template

 
@app.route('/about')
def about():
    return render_template('about.html')#render template
  

  
  
#route for handling the login page logic  
@app.route('/log', methods=['GET', 'POST'])
def log():
    error = None
    if request.method == 'POST':
        if request.form['username'] != 'admin' or request.form['password'] != 'admin':
            error = 'The Username/Password you entered is incorrect.PLease try again'
        else:
            session['logged_in'] = True
            flash('You are logged in!')
            return redirect(url_for('home'))
    return render_template('log.html', error=error)  
    
    
@app.route('/logout')
@login_required
def logout():
    session.pop('logged_in', None)
    flash('You logged out!')
    return redirect(url_for('home')) 
    



 
# start the server with the 'run()' method   
if __name__ == '__main__':
  app.run(debug=True)