application.py

from flask import Flask, render_template, url_for, request, redirect, flash, jsonify, make_response
from sqlalchemy import create_engine, asc, desc
from sqlalchemy.orm import sessionmaker
from functools import wraps
import os

from database_setup import Base, Category, Item, User

from flask import session as login_session
import random, string

from oauth2client.client import flow_from_clientsecrets
from oauth2client.client import FlowExchangeError
import httplib2
import json
import requests

app = Flask(__name__, template_folder='templates')

# Reads the Google details regarding client_id, etc.
CLIENT_ID = json.loads(open('client_secrets.json', 'r').read())['web']['client_id']
APPLICATION_NAME = "Item Catalog App"


# Connect to DB and create DB session
engine = create_engine('sqlite:///itemcatalog.db')
Base.metadata.bind = engine

DBSession = sessionmaker(bind=engine)
session = DBSession()


# Check for user login status
def login_required(f):
    @wraps(f)
    def decorated_function(*args, **kwargs):
        if 'username' in login_session:
            return f(*args, **kwargs)
        else:
            return redirect(url_for('showLogin', next=request.url))
    return decorated_function

# Create anti-forgery state token
@app.route('/login')
def showLogin():
	state = ''.join(random.choice(string.ascii_uppercase + string.digits) for x in xrange(32))
	login_session['state'] = state
	# return "The current session state is %s" % login_session['state']
	return render_template('login.html', STATE=state)



@app.route('/gconnect', methods=['POST'])
def gconnect():
    # Validate state token
    if request.args.get('state') != login_session['state']:
        response = make_response(json.dumps('Invalid state parameter.'), 401)
        response.headers['Content-Type'] = 'application/json'
        return response
    # Obtain authorization code
    code = request.data

    try:
        # Upgrade the authorization code into a credentials object
        oauth_flow = flow_from_clientsecrets('client_secrets.json', scope='')
        oauth_flow.redirect_uri = 'postmessage'
        credentials = oauth_flow.step2_exchange(code)
    except FlowExchangeError:
        response = make_response(
            json.dumps('Failed to upgrade the authorization code.'), 401)
        response.headers['Content-Type'] = 'application/json'
        return response

    # Check that the access token is valid.
    access_token = credentials.access_token
    url = ('https://www.googleapis.com/oauth2/v1/tokeninfo?access_token=%s'
           % access_token)
    h = httplib2.Http()
    result = json.loads(h.request(url, 'GET')[1].decode("utf8"))
    # If there was an error in the access token info, abort.
    if result.get('error') is not None:
        response = make_response(json.dumps(result.get('error')), 500)
        response.headers['Content-Type'] = 'application/json'
        return response

    # Verify that the access token is used for the intended user.
    gplus_id = credentials.id_token['sub']
    if result['user_id'] != gplus_id:
        response = make_response(
            json.dumps("Token's user ID doesn't match given user ID."), 401)
        response.headers['Content-Type'] = 'application/json'
        return response

    # Verify that the access token is valid for this app.
    if result['issued_to'] != CLIENT_ID:
        response = make_response(
            json.dumps("Token's client ID does not match app's."), 401)
        print "Token's client ID does not match app's."
        response.headers['Content-Type'] = 'application/json'
        return response

    stored_credentials = login_session.get('credentials')
    stored_gplus_id = login_session.get('gplus_id')
    if stored_credentials is not None and gplus_id == stored_gplus_id:
        response = make_response(json.dumps('Current user is already connected.'),
                                 200)
        response.headers['Content-Type'] = 'application/json'
        return response

    # Store the access token in the session for later use.
    login_session['access_token'] = credentials.access_token
    login_session['gplus_id'] = gplus_id

    # Get user info
    userinfo_url = "https://www.googleapis.com/oauth2/v1/userinfo"
    params = {'access_token': credentials.access_token, 'alt': 'json'}
    answer = requests.get(userinfo_url, params=params)

    data = answer.json()

    login_session['username'] = data['name']
    login_session['picture'] = data['picture']
    login_session['email'] = data['email']
    # ADD PROVIDER TO LOGIN SESSION
    login_session['provider'] = 'google'

    # see if user exists, if it doesn't make a new one
    user_id = getUserID(data["email"])
    if not user_id:
        user_id = createUser(login_session)
    login_session['user_id'] = user_id

    output = ''
    output += '<h1>Welcome, '
    output += login_session['username']
    output += '!</h1>'
    output += '<img src="'
    output += login_session['picture']
    output += ' " style = "width: 300px; height: 300px;border-radius: 150px;-webkit-border-radius: 150px;-moz-border-radius: 150px;"> '
    flash("you are now logged in as %s" % login_session['username'])
    print "done!"
    return output

# Disconnect Google user
@app.route('/gdisconnect')
def gdisconnect():
    access_token = login_session['access_token']

    """Ensure to only disconnect a connected user"""
    if access_token is None:
        response = make_response(json.dumps('Current user not connected'), 401)
        response.headers['Content-Type'] = 'application/json'
        return response

    """Execute HTTP GET request to revoke current token"""
    url = 'https://accounts.google.com/o/oauth2/revoke?token=%s' % login_session['access_token']
    h = httplib2.Http()
    result = h.request(url, 'GET')[0]

    if result['status'] == '200':
        """Reset the user's session"""
        del login_session['access_token']
        del login_session['gplus_id']
        del login_session['username']
        del login_session['email']
        del login_session['picture']

        flash("You've successfully logged out")
        return redirect(url_for('showHome'))
    else:
        """If the given token was invalid, do the following"""
        response = make_response(json.dumps("Failed to revoke token for given user"), 400)
        response.headers['Content-Type'] = 'application/json'
        return response



# User Functions
def createUser(login_session):
    newUser = User(name=login_session['username'], email=login_session[
                   'email'], picture=login_session['picture'])
    session.add(newUser)
    session.commit()
    user = session.query(User).filter_by(email=login_session['email']).one()
    return user.id

def getUserID(email):
    try:
        user = session.query(User).filter_by(email=email).one()
        return user.id
    except:
        return None

def getUserInfo(user_id):
    user = session.query(User).filter_by(id=user_id).one()
    return user




# API endpoints for all users.
@app.route('/users.json')
def userJSON():
    users = session.query(User).all()
    return jsonify(User = [u.serialize for u in users])

# API endpoints for all categories and items.
@app.route('/catalog.json')
def catalogJSON():
    categories = session.query(Category).all()
    items = session.query(Item).all()
    return jsonify(Categories = [c.serialize for c in categories], Items = [i.serialize for i in items])

# API endpoints for all categories.
@app.route('/categories.json')
def categoriesJSON():
    categories = session.query(Category).all()
    return jsonify(Categories = [c.serialize for c in categories])

# API endpoints for all items of a specific category.
@app.route('/catalog/<category_name>/items.json')
def itemsJSON(category_name):
    category = session.query(Category).filter_by(name=category_name).one()
    items = session.query(Item).filter_by(category=category).all()
    return jsonify(Items = [i.serialize for i in items])




# Show home page
@app.route('/')
@app.route('/catalog')
def showHome():
    categories = session.query(Category).order_by(asc(Category.name))
    items = session.query(Item).order_by(desc(Item.createdDate))
    if 'username' not in login_session:
        return render_template('publichome.html',
								categories=categories,
								items=items)
    else:
        return render_template('home.html',
								categories=categories,
								items=items)

# Show user info
@app.route('/user/<username>/<email>')
def showUser(username,email):
    user = session.query(User).filter_by(name=username,email=email).one()
    return render_template('showUser.html',
							user=user)

# Add a new category
@app.route('/catalog/newcategory', methods=['GET','POST'])
@login_required
def newCategory():
    if request.method == 'POST':
        addingCategory = Category(name=request.form['name'],
								user_id=login_session['user_id'])
        session.add(addingCategory)
        session.commit()
        return redirect(url_for('showHome'))
    else:
        return render_template('newCategory.html')

# Edit a category
@app.route('/catalog/<category_name>/edit', methods=['GET','POST'])
@login_required
def editCategory(category_name):
    categoryToEdit = session.query(Category).filter_by(name=category_name).one()

    """Prevent logged-in user to edit other user's category"""
    if categoryToEdit.user_id != login_session['user_id']:
        return ("<script>function myFunction() {alert('You are not"
				"authorized to edit this category. Please create"
				"your own " \
				"category " \
				"in order to edit.');}</script>"
				"<body onload='myFunction()'>")

    """Save edited category to the database"""
    if request.method == 'POST':
        categoryToEdit.name = request.form['name']
        session.add(categoryToEdit)
        session.commit()
        return redirect(url_for('showHome'))
    else:
        return render_template('editCategory.html',
								category=categoryToEdit)

# Delete a category
@app.route('/catalog/<category_name>/delete', methods=['GET','POST'])
@login_required
def deleteCategory(category_name):
    categoryToDelete = session.query(Category).filter_by(name=category_name).one()

    """Prevent logged-in user to delete other user's category"""
    if categoryToDelete.user_id != login_session['user_id']:
        return ("<script>function myFunction() {alert('You are not"
				"authorized to delete this category. Please create"
				"your own " \
				"category " \
				"in order to delete.');}</script>"
				"<body onload='myFunction()'>")

    """Delete category from the database"""
    if request.method == 'POST':
        session.delete(categoryToDelete)
        session.commit()
        return redirect(url_for('showHome'))
    else:
        return render_template('deleteCategory.html',
								category=categoryToDelete)

# Show all items in a category
@app.route('/catalog/<category_name>/items')
def showCategoryItems(category_name):
    categories = session.query(Category).order_by(asc(Category.name))
    chosenCategory = (session.query(Category)
    				.filter_by(name=category_name).one())
    items = (session.query(Item)
            .filter_by(category_id=chosenCategory.id)
            .order_by(asc(Item.name)))
    creator = getUserInfo(chosenCategory.user_id)
    if ('username' not in login_session 
    	or creator.id != login_session['user_id']):
        return render_template('publicCategoryItems.html',
								categories=categories, 
								chosenCategory=chosenCategory,
								items=items)
    else:
        return render_template('showCategoryItems.html', 
								categories=categories, 
								chosenCategory=chosenCategory, 
								items=items)

# Show information of a specific item
@app.route('/catalog/<category_name>/<item_name>')
def showItem(category_name, item_name):
    category = (session.query(Category)
				.filter_by(name=category_name).one())
    item = (session.query(Item)
			.filter_by(name=item_name, 
			category=category).one())
    creator = getUserInfo(item.user_id)
    if ('username' not in login_session 
    	or creator.id != login_session['user_id']):
        return render_template('publicitems.html', 
								item=item)
    else:
        return render_template('showItem.html',
								item=item, 
								creator=creator)

# Add a new item
@app.route('/catalog/newitem', methods=['GET','POST'])
@login_required
def newItem():
    categories = session.query(Category).order_by(asc(Category.name))
    if request.method == 'POST':
        itemName = request.form['name']
        itemDescription = request.form['description']
        itemCategory = (session.query(Category)
        .filter_by(name=request.form['category']).one())
        itemImage = request.form['image']
        if itemName != '':
            print "item name %s" % itemName
            addingItem = Item(name=itemName, 
				description=itemDescription, 
				image=itemImage, 
				category=itemCategory, 
				user_id=itemCategory.user_id)
            session.add(addingItem)
            session.commit()
            return redirect(url_for('showHome'))
        else:
            return render_template('newItem.html', 
									categories=categories)
    else:
        return render_template('newItem.html', 
								categories=categories)

# Edit an item
@app.route('/catalog/<category_name>/<item_name>/edit', methods=['GET','POST'])
@login_required
def editItem(category_name, item_name):
    categories = session.query(Category).order_by(asc(Category.name))
    editingItemCategory = (session.query(Category).filter_by(name=category_name).one())
    editingItem = (session.query(Item)
    				.filter_by(name=item_name, 
    				category=editingItemCategory).one())

    """Prevent logged-in user to edit item which belongs to other user"""
    if editingItem.user_id != login_session['user_id']:
        return ("<script>function myFunction()" 
					"{alert('You are not authorized to edit this item."
					"Please create your own item " \
					"in order to edit.');}</script>"
					"<body onload='myFunction()'>")

    """Save edited item to the database"""
    if request.method == 'POST':
        if request.form['name']:
            editingItem.name = request.form['name']
        if request.form['description']:
            editingItem.description = request.form['description']
        if request.form['category']:
            editingItem.category = session.query(Category).filter_by(name=request.form['category']).one()
        session.add(editingItem)
        session.commit()
        return redirect(url_for('showItem', 
				category_name=editingItemCategory.name, 
				item_name=editingItem.name))
    else:
        return render_template('editItem.html', 
								categories=categories, 
								editingItemCategory=editingItemCategory,
								item=editingItem)

# Delete an item
@app.route('/catalog/<category_name>/<item_name>/delete', methods=['GET','POST'])
@login_required
def deleteItem(category_name, item_name):
    category = session.query(Category).filter_by(name=category_name).one()
    deletingItem = session.query(Item).filter_by(name=item_name, category=category).one()

    if deletingItem.user_id != login_session['user_id']:
        return ("<script>function myFunction() "
				"{alert('You are not authorized to delete this item."
				" Please create your own item " \
				"in order to delete.');}</script>"
				"<body onload='myFunction()'>")

    """Delete item from the database"""
    if request.method == 'POST':
        session.delete(deletingItem)
        session.commit()
        return redirect(url_for('showCategoryItems', 
								category_name=category.name))
    else:
        return render_template('deleteItem.html', 
								item=deletingItem)

# Edit item image
@app.route('/catalog/<category_name>/<item_name>/editimage', methods=['GET','POST'])
@login_required
def editImage(category_name, item_name):
    category = session.query(Category).filter_by(name=category_name).one()
    editingItem = session.query(Item).filter_by(name=item_name, category=category).one()

    if editingItem.user_id != login_session['user_id']:
        return ("<script>function myFunction() "
				"{alert('You are not authorized to edit this item."
				" Please create your own item " \
				"in order to edit.');}</script>"
				"<body onload='myFunction()'>")

    """Save edited image to the database"""
    if request.method == 'POST':
        if request.form['image']:
            editingItem.image = request.form['image']
            session.add(editingItem)
            session.commit()
            return redirect(url_for('showItem', 
									category_name=category.name, 
									item_name=editingItem.name))
    else:
        return render_template('editImage.html',
								item=editingItem)

# Delete item image
@app.route('/catalog/<category_name>/<item_name>/deleteimage', methods=['GET','POST'])
@login_required
def deleteImage(category_name, item_name):
    category = session.query(Category).filter_by(name=category_name).one()
    editingItem = session.query(Item).filter_by(name=item_name, category=category).one()

    """Prevent logged-in user to delete item image which belongs to other user"""
    if editingItem.user_id != login_session['user_id']:
        return ("<script>function myFunction() "
				"{alert('You are not authorized to delete this item."
				" Please create your own item " \
				"in order to delete.');}</script>"
				"<body onload='myFunction()'>")

    """Delete item image"""
    if request.method == 'POST':
        editingItem.image = url_for('static', filename='img_not_available.png')
        session.add(editingItem)
        session.commit()
        return redirect(url_for('showItem', 
								category_name=category.name, 
								item_name=editingItem.name))
    else:
        return render_template('deleteImage.html', item=editingItem)




if __name__ == '__main__':
	app.secret_key = 'GP17535HYS01WGMS'
	app.debug = True
	app.run(host = '0.0.0.0', port = 8000)