psych_pure

demo.rb

require "psych"
require "psych/pure"

# Let's create a rich YAML document with various types and comments
yaml_source = <<~YAML
  # Configuration for our awesome application
  ---
  database: # Database settings
    host: localhost # Can be changed for production
    port: 5432 # Default PostgreSQL port
    credentials:
      username: admin # Super user access
      password: secret123 # TODO: Move to env vars!

  # Feature flags and settings
  features:
    enabled_modules: # Current active modules
      - authentication # Required for security
      - reporting # Business intelligence
      - api # External integration
    rate_limiting: # API rate limiting
      enabled: true # Protect against abuse
      max_requests: 1000 # Requests per hour
      
  # Environment-specific configurations
  environments:
    production: &prod # Production environment
      url: https://prod.example.com
      workers: 8 # Optimal for our current server
    staging: # Staging environment
      <<: *prod # Inherit from production
      url: https://staging.example.com
      workers: 4 # Reduced workers for staging
YAML

# Load the YAML with comments
config = Psych::Pure.load(yaml_source, comments: true, aliases: true)

puts "=== Original Configuration ==="
puts Psych::Pure.dump(config)

# Make some modifications to demonstrate comment preservation
# and structure modification

# Update some values
config["database"]["port"] = 5433
config["features"]["rate_limiting"]["max_requests"] = 1500

# Add new elements
config["features"]["enabled_modules"] << "monitoring"
config["database"]["pool_size"] = 25

# Modify nested structure
config["environments"]["development"] = {
  "url" => "http://localhost:3000",
  "workers" => 2
}

# Output the modified configuration
puts "=== Modified Configuration ==="
puts Psych::Pure.dump(config)

# Let's also demonstrate accessing the structure
puts "\n=== Current Settings ==="
puts "Database Port: #{config["database"]["port"]}"
puts "Enabled Modules: #{config["features"]["enabled_modules"].join(", ")}"
puts "Production Workers: #{config["environments"]["production"]["workers"]}"