If you have been within the software development industry for the last 20 years, you most certainly have heard of a programming language named Python. Created by Guido van Rossum, Python first appeared in 1991 and has captured the hearts of many software developers across the globe ever since.
However, how is it that a language that is over 20 years old is still around and is gaining more and more popularity every day?
Well, the answer to this question is simple. Python is awesome for everything (or almost everything). Python is a general-purpose programming language, which means that you can create simple terminal applications, web applications, microservices, games, and also complex scientific applications. Even though it is possible to use Python for different purposes, Python is a language that is well known for being easy to learn, which is perfect for beginners as well as people with no computer science background.
Python is a batteries included programming language, which means that most of the time you will not need to make use of any external dependencies when developing your projects. Python's standard library is feature rich and most of the time contains everything you need to create your programs, and just in case you need something that is not in the standard library, the PyPI (Python Package Index) currently contains 117,652 packages.
The Python community is welcoming, helpful, diverse, and extremely passionate about the language, and everyone in the community is always happy to help each other.
If you still not convinced, the popular website StackOverflow published this year's statistics about the popularity of programming languages based on the number of questions the users add to the site, and Python is one of the top languages, only behind JavaScript, Java, C#, and PHP.
It is a perfect time to be a Python developer, so let's get started!
This book is for software developers who are familiar with Python and want to gain hands-on experience with web and software development projects. Basic knowledge of Python programming is required.
Chapter 1, Implementing the Weather Application, guides you through developing a terminal application that shows the current weather for a specific region and a forecast for the next 5 days. This chapter will introduce you to the basic concepts of Python programming. You will learn how to parse command-line arguments to add more interactivity to programs, and you will finally see how to scrape data from websites using the popular Beautiful Soup framework.
Chapter 2, Creating a Remote-Control Application with Spotify, will teach you how to perform authentication with the Spotify API using OAuth. We will use the curses library to make the application more interesting and user-friendly.
Chapter 3, Casting Votes on Twitter, will teach you how to use the Tkinter library to create beautiful user interfaces using Python. We will use Reactive Extensions for Python to detect when a vote has been made in the backend, after which, we will publish the changes in the user interface.
Chapter 4, Exchange Rates and the Currency Conversion Tool, will enable you to implement a currency converter that will get foreign exchange rates in real time from different sources and use the data to perform currency conversion. We will develop an API that contains helper functions to perform the conversions. To start with, we will use opensource foreign exchange rates and a currency conversion API (http://fixer.io/). The second part of the chapter will teach you how to create a command-line application makes use of our API to fetch data from the data sources and also get the currency conversion results with a few parameters.
Chapter 5, Building a Web Messenger with Microservices, will teach you how to use Nameko, a microservice framework for Python. You will also learn how to make dependency providers for external resources such as Redis. This chapter will also touch upon integration testing Nameko services and basic AJAX requests to an API.
Chapter 6, Extending TempMessenger with a User Authentication Microservice, will build upon your app from Chapter 5, Building a Web Messenger with Microservices. You will create a user authentication microservice that stores users in a Postgres database. Using Bcrypt, you will also learn how to store passwords in a database securely. This chapter also covers creating a Flask web interface and how to utilize cookies to store web session data. By the end of these chapters, you will be well equipped to create scalable and cohesive microservices.
Chapter 7, Online Video Game Store with Django, will enable you to create an online video game store. It will contain features such as browsing video games by category, performing searches using different criteria, viewing detailed information about each game, and finally adding games to a shopping cart and placing an order. Here, you will learn about Django 2.0, the administration UI, the Django data model, and much more.
Chapter 8, Order Microservice, will help you build a microservice that will be responsible for receiving orders from the web application that we developed in the previous chapter. The order microservice also provides other features such as the ability to update the status of orders and provide order information using different criteria.
Chapter 9, Notification Serverless Application, will teach you about Serverless functions architecture and how to build a notification service using Flask and deploy the final application to AWS Lambda using the great project Zappa. You will also learn how to integrate the web application that was developed in Chapter 7, Online Video Game Store with Django, and the order microservice developed in Chapter 8, Order Microservice, with the serverless notification application.
In order to execute the code from this book on your local machine, you will need the following:
- An internet connection
- Virtualenv
- Python 3.6
- MongoDB 3.2.11
- pgAdmin (refer to the official documentation at http://url.marcuspen.com/pgadmin for installation instructions)
- Docker (refer to the official documentation at http://url.marcuspen.com/docker-install for installation instructions)
All other requirements will be installed as we progress through the chapters. All instructions in this chapter are tailored toward macOS or Debian/Ubuntu systems; however, the authors have taken care to only use cross-platform dependencies.
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