Go Language Basics

DevOps is a concept that has been floating around since the early 2000s. It is a popularization of an operations discipline that relies on programming skills with development psychology popularized by Agile.

Site reliability engineering (SRE) is now considered a subdiscipline of DevOps, though it is likely the precursor to DevOps and relies more heavily on software skills and Service - Level Obligation (SLO)/Service - Level Agreement (SLA) modeling.

During my early time at Google, like many of today's DevOps shops, we used Python heavily. I think C++ was too painful for many SREs, and we had Python celebrities in Guido van Rossum and Alex Martelli.

But, as time wore on, many of the groups working in Python started having scaling issues. This included everything from Python running out of memory (requiring us to hack in our own malloc) to the Global Interpreter Lock (GIL) preventing us from true multithreading. At scale, we found that the lack of static types was giving us an abundance of errors that should have been caught at compile time. This mirrored what production services had seen years before.

But, Python came with more than compile-time and service-scaling issues. Simply moving to a new version of Python in the fleet might cause a service to stop working. The Python version run on Google machines would often get upgraded and expose bugs in your code that the previous version did not. Unlike a compiled binary, you could not just roll back to an old version.

Several of us in different organizations were looking to solve these types of problems without having to use C++. For my personal journey, I heard about Go from my colleagues in our Sydney office (Hey, Ross!). It was the pre-1.0 days, but they said it was already showing a lot of promise. I can't say I was even remotely convinced that what we needed was another language.

About 6 months later, however, I had bought Go hook, line, and sinker. It had everything we needed without everything we didn't. Now, it was still pre-1.0 days, so there was a certain amount of churn back then that was unpleasant (such as finding that Russ Cox had changed the time package over the weekend, so I had to rewrite a bunch of code). But, the benefits after writing my first service were undeniable.

I spent the next 4 years moving my department from a complete Python shop to almost a complete Go shop. I started teaching classes in Go across the world, targeted at operations engineers, rewriting core libraries for Go, and evangelizing to what was probably an annoying amount. Just because Go was invented at Google, it didn't mean that the engineers wanted to throw away their Python code and learn something new; there was more than a little resistance.

Now, Go has become the de facto language for cloud orchestration and software in the larger world (from Kubernetes to Docker). Go comes with all the tools you need to make huge strides in the reliability of your tooling and ability to scale.

Because many of these cloud services are written in Go, their parts are available to you by accessing their packages for your own tooling needs. This can make writing tooling for the cloud an easier experience.

For the next two chapters, I will be sharing my 10+ years' experience of teaching Go to engineers around the world to give you the basics and essentials of the Go language. Much of what you will read here is based on my free Go basics video training course, https://www.golangbasics.com. This course will differ slightly from that one in that it is more condensed. As you work your way through the book, we will continue to extend your knowledge of the Go language's standard library and third-party packages.

This chapter will cover the following main topics:

• Using the Go Playground
• Utilizing Go packages
• Using Go's variable types
• Looping in Go
• Using conditionals
• Learning about functions
• Defining public and private
• Using arrays and slices
• Getting to know about structs
• Understanding Go pointers
• Comprehending Go interfaces

Now, let's get the basics down and get you on your way!