application.py

# $ pip install --upgrade -r requirements.txt
# $ python -m flask run

from api_key_verification import STATION_KEY
from flask import Flask, Response, redirect, url_for, request, session, abort
import flask_login
from flask_login import LoginManager, UserMixin, \
                                login_required, login_user, logout_user
from flask import render_template
from forms import FindVoterForm
from forms import LoginForm
from flask import request
from flask import flash
import urllib, urllib2
import json
import pdfs

import models as db
from passlib.apps import custom_app_context as pwd_context
# Configuration. Example cases for TESTING
SECRET_KEY = 'development key'

TEMPLATES_AUTO_RELOAD = True

application = Flask(__name__)
application.config.from_object(__name__)

login_manager = LoginManager()
login_manager.init_app(application)
login_manager.login_view = "login"

SEARCH_VOTER_URL = "http://voting.eelection.co.uk/get_voters"
PIN_URL = "http://pins.eelection.co.uk/get_pin_code"

# User model
class User(UserMixin):

    def __init__(self, id, username, station_id):
        self.id = id
        self.station_id = station_id
        self.username = username

    def __repr__(self):
        return "%s/%d" % (self.username, self.station_id)

@application.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        form = LoginForm(request.form)
        username = request.form['username']
        password = request.form['password']
        valid_user = get_valid_user(username, password)
        if valid_user:
            user = User(valid_user[0], username, valid_user[1])
            login_user(user)
            return redirect('')
        else:
            return render_template('login.html', message="Login unsuccessful.", form=form)
    else:
        form = LoginForm(request.form)
        return render_template('login.html', form=form)

def get_valid_user(username, password):
    users = db.retrieveUsers()
    user_id = -1
    station_id = -1
    for user in users:
        if user[1] == username:
            password_hash = user[2]
            if pwd_context.verify(password, password_hash):
                user_id = user[0]
                station_id = user[3]
                return (user_id, station_id)
            break
    return None

@application.route("/logout")
@login_required
def logout():
    logout_user()
    return redirect('/login')

# handle login failed
@application.errorhandler(401)
def page_not_found(e):
    return render_template('login.html', message="Login unsuccessful.", form=form)

# callback to reload the user object
@login_manager.user_loader
def load_user(userid):
    users = db.retrieveUsers()
    users_with_id = filter(lambda x: x[0] == int(userid), users)
    if users_with_id:
        user = users_with_id[0]
        return User(user[0], user[1], user[3])
    else:
        return None

# Once logged in successfully, use station app to search voter
@application.route('/', methods=['GET'])
@login_required
def station():
    form = FindVoterForm(request.form)
    return render_template('station.html', form=form)

# When the clerk clicks search for voter
@application.route('/', methods=['POST'])
@login_required
def find_voter():
    form = FindVoterForm(request.form)
    if form.validate_on_submit():
        firstname = request.form['firstname']
        postcode = request.form['postcode']
        postcode = postcode.upper()
        url = createSearchURL(firstname, postcode)
        get_request = urllib2.Request(url)
        get_request.add_header("Authorization", STATION_KEY);
        dbresult = urllib2.urlopen(get_request).read()
        resultjson = json.loads(dbresult)
        success = resultjson['success']
        voters = resultjson['voters']
        session['voters'] = voters
        if success:
            # matching entry found
            #return render_template('voterdb.html', voters=voters)
            return render_template('station.html', form=form, voters=voters)
        # no matching entry in database, try again
        return render_template('station.html', form=form, message="No matching entry found. Please try again.")
    # This means they have submitted an invalid form
    return render_template('station.html', form=form, message="Invalid form submitted. Please try again.")

# When the clerk clicks get pin for that voter
@application.route('/voterpincard', methods=['POST'])
@login_required
def voterpincard():
    voterid = None
    form = FindVoterForm(request.form)
    if request.method == "POST":
        # Voter id is the name of the only button in the form
        voterid = 0
        for form_vote_id, button_name in request.form.iteritems():
            if button_name == 'Request PIN' or button_name == 'New PIN':
                voterid = form_vote_id
        # If there was a voterid, get a pin and return the pin card
        if voterid is not 0:
            url = createPinURL(voterid)
            get_request = urllib2.Request(url)
            get_request.add_header("Authorization", STATION_KEY);
            dbresult = urllib2.urlopen(get_request).read()
            resultjson = json.loads(dbresult)
            success = resultjson['success']
            voter_pin = resultjson['pin_code']
            if success:
                # Get the pin card pdf for that voter
                return pdfs.create_pdf(voter_pin)
            else:
                # Must go back to voter database page_not_found
                error_message = "Could not find PIN for that voter. Try again."
                if voters in session:
                    return render_template('station.html', form=form, voters=session['voters'], message=error_message)
        error_message = "Could not find voter ID. Try again."
        return render_template('station.html', form=form, message=error_message)

def createSearchURL(firstname, postcode):
    firstname = firstname.strip()
    postcode = postcode.strip()
    # Add a space 3 characters from the end of the postcode if one doesn't exist
    if postcode[len(postcode)-4] != ' ':
        postcode = postcode[:len(postcode)-3] + ' ' + postcode[len(postcode)-3:]
    station_id = "/station_id/" + urllib.quote(str(flask_login.current_user.station_id))
    firstname = "/voter_name/" + urllib.quote(firstname)
    postcode = "/postcode/" + urllib.quote(postcode)
    url = SEARCH_VOTER_URL +station_id + firstname + postcode
    return url

def createPinURL(voter_id):
    station_id = "/station_id/" + urllib.quote(str(flask_login.current_user.station_id))
    voter_id = "/voter_id/" + urllib.quote(voter_id)
    url = PIN_URL + station_id + voter_id
    return url

if __name__ == "__main__":
    # Setting debug to True enables debug output. This line should be
    # removed before deploying a production app.
    application.debug = True
    application.run()