Introduction

In the world of configuration management, YAML has become a de facto standard. However, when dealing with complex configurations, the need for better inheritance and merging capabilities becomes apparent. Today, I want to introduce you to YamlExtensions, a Ruby gem that solves this exact problem.

The Problem with Standard YAML Merging

Standard YAML offers basic merging with the << operator, but it falls short when dealing with nested structures. This limitation often leads to duplicate configurations or complex workarounds.

Enter YamlExtensions

YamlExtensions introduces a powerful feature: deep merging using the <<< operator. This simple yet effective enhancement allows for more sophisticated configuration management.

How It Works

Let's look at a practical example:

defaults: &DEFAULTS
  hello: world
  this:
    is:
      even: deeper

main:
  <<<: *DEFAULTS
  this:
    is:
     somewhat: deep

The gem intelligently merges nested structures, maintaining both the original and overridden values where appropriate.

Multiple Deep Merges

One particularly powerful feature is the ability to perform multiple deep merges by appending numbers to the <<< operator:

main:
  <<<1: *DEFAULTS
  <<<2: *OVERRIDES
  this:
    is:
     somewhat: deep

Getting Started

After installation, simply require the gem in your Ruby code:

require 'yaml_extensions'

YamlExtensions will freedom patch Ruby's YAML implementation to support the aforementioned features.


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