#DesignPatterns Posts

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Marko Mišura
The Comprehensive Guide to JavaScript Design Patterns

As a good JavaScript developer, you strive to write clean, healthy, and maintainable code. While you solve interesting and unique challenges, you’ve likely found that you’re often writing code that looks similar to the code for an entirely different problem you’ve handled before. You may not know it, but you’ve used a design pattern.

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Sergey Kolodiy
Unit Tests, How to Write Testable Code and Why it Matters

In this article, I will show that unit testing itself is quite easy; the real problems that complicate unit testing, and introduce expensive complexity, are a result of poorly-designed, untestable code. We will discuss what makes code hard to test, which anti-patterns and bad practices we should avoid to improve testability, and what other benefits we can achieve by writing testable code. We will see that writing testable code is not just about making testing less troublesome, but about making the code itself more robust, and easier to maintain.

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Ahmed AbdelRazzak
The Publish-Subscribe Pattern on Rails: An Implementation Tutorial

The publish-subscribe pattern] (or pub/sub, for short) is a messaging pattern where senders of messages (publishers), do not program the messages to be sent directly to specific receivers (subscribers). Instead, the programmer “publishes” messages (events), without any knowledge of any subscribers there may be.

This article provides insight in how to use the pub/sub pattern, in Rails, to communicate messages between different system components without these components knowing anything about each other’s identity.

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