Book Image

Python Network Programming Techniques

By : Marcel Neidinger
Book Image

Python Network Programming Techniques

By: Marcel Neidinger

Overview of this book

Network automation offers a powerful new way of changing your infrastructure network. Gone are the days of manually logging on to different devices to type the same configuration commands over and over again. With this book, you'll find out how you can automate your network infrastructure using Python. You'll get started on your network automation journey with a hands-on introduction to the network programming basics to complement your infrastructure knowledge. You'll learn how to tackle different aspects of network automation using Python programming and a variety of open source libraries. In the book, you'll learn everything from templating, testing, and deploying your configuration on a device-by-device basis to using high-level REST APIs to manage your cloud-based infrastructure. Finally, you'll see how to automate network security with Cisco’s Firepower APIs. By the end of this Python network programming book, you'll have not only gained a holistic overview of the different methods to automate the configuration and maintenance of network devices, but also learned how to automate simple to complex networking tasks and overcome common network programming challenges.
Table of Contents (14 chapters)

Executing code until a condition is met using while loops

A very common use case for command-line programs is to keep asking a user for more information until a certain condition is met. With our current set of tools, this would be difficult. We know how to ask a user for information (using the input() function) and we know how to check information (using if clauses), but how could we keep executing a piece of code until a condition (that is, the correct input from a user) is met? We could use a for loop with an extremely high number, but this number would also eventually come to an end.

To address this, Python includes a while loop. while loops are essentially a combination of a loop and an if clause that allow us to execute a piece of code until a condition is met.

In this recipe, you'll see how to use a while loop to keep asking a user for more IP addresses that we will add to a list. Once the user is satisfied with the addresses they have added, we will terminate the...