# Copyright 2017, 2013, 2011 Pearson Education, Inc., W.F. Punch & R.J.Enbody
from flask import Flask, render_template_string, request
from wtforms import Form, validators, TextField
import string
app = Flask(__name__)
# function is the model. Calculate if original_str is a palindrome
# return a string
def compute(original_str):
bad_chars = string.whitespace + string.punctuation
modified_str = original_str.lower()
for char in modified_str:
if char in bad_chars: # remove bad characters
modified_str = modified_str.replace(char,'')
if modified_str == modified_str[::-1]:
return "It's a palindrome!"
else:
return "It is not a palindrome :-("
# html page is the view.
page = '''
Palindrome Calculation
Check if a String is a Palindrome
'''
# InputForm and below is our controller
# form with a single TextField
class InputForm(Form):
text_field = TextField(validators=[validators.InputRequired()])
@app.route('/', methods=['GET', 'POST'])
def index():
palindrome_result = None
form = InputForm(request.form)
if request.method == 'POST' and form.validate():
input_val = form.text_field.data
palindrome_result = compute(input_val)
return render_template_string(page, template_form=form, result = palindrome_result)
if __name__ == '__main__':
app.run(debug=True)