Book Image

Modern Python Standard Library Cookbook

By : Alessandro Molina
Book Image

Modern Python Standard Library Cookbook

By: Alessandro Molina

Overview of this book

The Python 3 Standard Library is a vast array of modules that you can use for developing various kinds of applications. It contains an exhaustive list of libraries, and this book will help you choose the best one to address specific programming problems in Python. The Modern Python Standard Library Cookbook begins with recipes on containers and data structures and guides you in performing effective text management in Python. You will find Python recipes for command-line operations, networking, filesystems and directories, and concurrent execution. You will learn about Python security essentials in Python and get to grips with various development tools for debugging, benchmarking, inspection, error reporting, and tracing. The book includes recipes to help you create graphical user interfaces for your application. You will learn to work with multimedia components and perform mathematical operations on date and time. The recipes will also show you how to deploy different searching and sorting algorithms on your data. By the end of the book, you will have acquired the skills needed to write clean code in Python and develop applications that meet your needs.
Table of Contents (21 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

Building HTML


Whenever you are building a web page, an email, or a report, you are probably going to rely on replacing placeholders in an HTML template with actual values that you need to show to your users.

We already saw in Chapter 2, Text Management, how a minimal, simple template engine can be implemented, but it wasn't specific to HTML in any way.

When working with HTML, it's particularly important to pay attention to escaping the values provided by users, as that might lead to broken pages or even XSS attacks.

You clearly don't want your users to get mad at you just because you registered yourself on your website with the surname "<script>alert('You are hacked!')</script>".

For this reason, the Python standard library provides escaping tools that can be used to properly prepare content for insertion into HTML.

How to do it...

Combining the string.Formatter and cgi modules, it is possible to create a formatter that takes care of escaping for us:

import string
import cgi

class...