Recent Articles

How to Parse JSON That Varies Between an Array or a Single Item With Go

Have you ever interact with an API that returns variable data formats depending on the circumstances? Yeah, it's a pain. In this post we explore one particular situation - when the response can either be an array or a single item - and look at how to handle unmarshaling the JSON in Go.

Creating a Live Reloader in Less than 200 Lines of Go Code

Read about the process of building a live-reloader in Go in less than 200 lines of Go code. The live reloading is done via polling so that it works in environments where file change events aren't available, such as docker containers in some scenarios.

Working From Home: Separating Your Personal and Work Life

With the recent surge in working from home (WFH), I wanted to take some time to share some lessons, tips, and experiences about WFH. I’m not naive enough to believe that I have all of the answers, especially amid school closings and the million other unique factors brought about by COVID-19, but there are many lessons that I have learned over the last 8 or so years working remotely that I believe will still be helpful.

More Effective DDD with Interface Test Suites

When using domain driven design in Go, there are a few techniques that can be paired with DDD for a better overall experience. One of those is interface test suites - tests designed to run against any implementation of an interface. In this article we explore what interface test suites are, how to utilize them, and why they pair so well with DDD.

Moving Towards Domain Driven Design in Go

Domain driven design sounds great in theory, but how is it applied in Go? In this article we explore some code as it slowly evolves into DDD, learning how and why each decision is made along the way and what benefits it will provide us in the future. We then discuss the pros and cons of starting with a more domain-focuses design.

Using MVC to Structure Go Web Applications

MVC is a well-known way to structure web applications, but it is often shunned in Go. In this article we explore how MVC can be effectively implement in Go as well as how to avoid all of the issues that many people associate with MVC.

Popular Articles

6 Tips for Using Strings in Go

Learn how to perform common operations with strings in Go. This article discusses how to write multiline strings, concatenate strings efficiently, convert various data types into strings, checking for prefixes, and converting strings to byte slices.

Using Functions Inside Go Templates

Go's template package provides many useful built-in functions. Learn to use a few of the more common ones, as well as how to add custom fucntions to your templates so that you can add any functionality you need.

Connecting to a PostgreSQL database with Go's database/sql package

This tutorial explains how to connect to a Postgres DB using the database/sql and lib/pq packages. It also covers potential errors and solutions.

Creating Random Strings in Go

A tutorial explaining how to create a custom rand package with functions for creating random strings of varying length with custom of preset character sets.

Inserting records into a PostgreSQL database with Go's database/sql package

Learn to insert new records into a Postgres database using Go's database/sql package, along with how to get the resulting ID of newly created records.

How to use slice capacity and length in Go

Learn about the difference between capacity and length and how to properly utilize them to make your Go code faster, cleaner, and memory efficient.

My Latest Progress Update

Writing Course Notes

In this progress update we explore why it takes me so long to complete a project when using it to come up with course notes. I'll also give you an inside look at my notes that I use for courses.

View past progress updates

↓ Or check out some of my longer series. ↓

Each series covers a broader topic and is composed of several articles

Using PostgreSQL with Go

PostgreSQL is an open source relational database system that has been around for well over a decade and has proven to be a great all around storage choice when developing a web application.

In this series we are going to walk through everything from first installing PostgreSQL 9.5 all the way to using it with a Go application. While this post will cover all of the basics required to get started using SQL with Golang, it is not a full course on SQL. It is instead intended to guide you by giving you enough information to be productive, while not overloading you with details that can be learned as you progress.

In this series we will cover topics like:

  • Installing PostgreSQL on various operating systems (Ubuntu Linux, Mac OS, etc)
  • Interacting with a PostgreSQL database using raw SQL. This includes querying, inserting, updating, and deleting records.
  • Interacting with a PostgreSQL database using the database/sql package provided by Go's standard library. Again, this includes querying, inserting, updating, and deleting records.
  • Using ORMs and other third party librarys to interact with SQL databases
Let's Learn Algorithms

This series is no longer being updated. Instead, check out the course I created based on it - Algorithms with Go

Algorithms are a core component in a computer science education, and when taught properly they can help a developer improve his or her skills massively. In this series we will work to both understand how common computer algorithms work, as well as how to properly code each of them in Go.

By coding each algorithm as we learn it, you will develop the skills necessary to translate a conceptual idea into correct and efficient code. While many developers will know how to solve a problem set before them, oftentimes bugs and issues can stem from minor mistakes that algorithm practice can help remedy.

In addition to coding each algorithm we will also discuss how it works as well as the efficiency of each algorithm. That is, we will discuss how fast or slow the code will be based on the size of the input. This is important because in many real world situations you can opt for simpler - but slower - code if you know your inputs won't be too large. Alternatively, you could determine that the simpler solution won't work for your inputs and know that you will need to spend some extra time on a more efficient algorithm.

If you are relatively new to programmer, or simply don't have a formal computer science education, I invite you to check out these articles. You won't be disappointed!

Avatar of Jon Calhoun
Articles and Tutorials by
Jon Calhoun

Jon Calhoun is a full stack web developer who teaches about Go, web development, algorithms, and anything programming. If you haven't already, you should totally check out his Go courses.

Previously, Jon worked at several statups including co-founding EasyPost, a shipping API used by several fortune 500 companies. Prior to that Jon worked at Google, competed at world finals in programming competitions, and has been programming since he was a child.

Recent Articles All Articles Mini-Series Progress Updates Tags About Me Go Courses

©2018 Jonathan Calhoun. All rights reserved.