Tag golang

Flattening the Package Structure

Creating an organized code structure can be a complex endeavor. Previously, I penned a blog post entitled How to structure Go code?, an attempt to demystify this topic. While I stand by the insights shared, I’ve come to realize that the article is somewhat generic and lacks clear, tangible answers to the question at hand. There’s arguably no better way to understand such concepts than by diving into concrete examples. Today, I’d like to discuss the evolution of a package named productcatalog and explain why I chose to streamline its structure.

New project: ecommerce

I’m excited to share with you my new project - an open-source e-commerce platform. The frontend is built with ReactJS and the backend is written in Go. Project Goals The goal of this project is to: Continuously improve and develop the platform. Provide an opportunity for less experienced programmers to gain experience working on a real project. Experiment with various methodologies and tools that may not be available in other work settings (event-driven architecture, DDD, event sourcing, and more).

Password policies

One of tasks I was working on recently is related to password policies. Of course, everything is configurable in code right now. In this note I want to tell you about some my decisions and how I got to them. My first idea was creating an interface that any policy will have to satisfy. type PasswordPolicy interface { Verify(pass string) error } That make sense, doesn’t it? When I was working on specific policy implementation I had a feeling that the type doesn’t have to be an interface.

Memory-wall problem

The memory wall problem refers to a phenomenon that occurs in computer architecture when the processor’s speed outpaces the rate at which data can be transferred to and from the memory system. As a result, the processor must wait for the data to be fetched from memory, which slows down its performance and limits its speed. The memory wall problem has become increasingly significant as processors have become faster and more powerful while memory speeds have not kept pace with these advancements.

Why We Should Avoid Using `else` in Programming

The else keyword is a commonly used control structure in programming. It allows us to execute a block of code if a condition is not true. However, overusing else statements can lead to less readable and maintainable code. In this article, we’ll explore why we should avoid using else clauses in our code and look at some alternatives that can make our code more concise and readable. Why Overusing else is a Bad Idea One of the main arguments against using else statements is that they can make our code more complex and harder to read.

Writing tests in Go (business apps)

There are many practices and tactics that tackle testing. Today, I’ll share with you how I write tests for my projects. Please notice that you may find it useful when starting a new project or an independent part of existing applications. You may find it difficult to apply in an already existing application. It’s not impossible but it may be challenging. Table of content General rules for tests Works out of the box Single responsible As simple as possible Irrelevant code should be extracted How does the architecture of the package look like?

Top level logging

I like having the core logic of our application free of distractions like too many technical “details” like logging or generating metrics. Of course, sometimes it’s hard to avoid it. I found in many projects a situation where we put the logger very deeply inside of the code. At the end of the day, we had the logger almost everywhere. In tests, we had to provide the mocked implementation everywhere as well.

`replace` directive in go modules

Sometimes, we may want to use a library but a slightly modified version. It happens very often when we develop the library but test it in the context of an application. Go has a handy mechanism in go modules that can help us with it. To make it work, we have to clone the library somewhere near the target project and run the following command in the application’s folder. go mod edit -replace github.

gRPC with SSL/TLS

gRPC supports authentication. Adding it to your project is simple. All you have to do is configure it with just a few lines of code. One of the authentication types that gRPC supports is SSL/TLS. From the server-side, the code looks like this: creds, err := credentials.NewServerTLSFromFile(certFile, keyFile) if err != nil { // handle the error - no ignore it! } s := grpc.NewServer(grpc.Creds(creds)) The client has to update the code as shown below.

How to structure Go code?

Programs should be written for people to read, and only incidentally for machines to execute - Abelson and Sussman It is one of the most popular questions. You can find on the Internet attempts to answer this question. I’ve had concerns if I’m designing my packages or even the whole project correctly. Today, I’m not 100% sure about that! Some time ago, I had the pleasure to meet Robert Griesemer (one of Go’s authors) in person.