For my own gems, I want to have a configuration block, which usually looks like this:
Yourgem.configure do |config|
config.some_config = "foobarbaz"
end
There are a lot of articles how to implement this functionality:
- Ruby Gem Configuration Patterns
- MyGem.configure Block
- Creating a configurable Ruby gem
- RubyGem Configuration Pattern
- The easiest configuration block for your Ruby gems
- Ruby Gem Configuration Pattern
- …
Isn’t it still looks too complicated? Can’t be a configuration object just a plain ruby hash?
Yes, it can:
module Yourgem
def self.configuration
@configuration ||= {}
end
def self.configure
yield(configuration)
end
end
And now:
Yourgem.configure do |config|
config[:some_config] = "foobarbaz"
end
Yourgem.configuration # => { :some_config => "foobarbaz" }
Yourgem.configuration[:some_config] #=> "foobarbaz"
Looks clean and simple, but there is one restriction: instead of classy Yourgem.configuration.some_config
we have to act with it like with hash (because configuration value it’s a hash): Yourgem.configuration[:some_config]
. To solve this problem, we’ll use Ruby’s built-in OpenStruct:
require 'ostruct'
module Yourgem
def self.configuration
@configuration ||= OpenStruct.new
end
def self.configure
yield(configuration)
end
end
And now:
Yourgem.configure do |config|
config.some_config = "foobarbaz"
end
Yourgem.configuration # => #<OpenStruct some_config="foobarbaz">
Yourgem.configuration.some_config #=> "foobarbaz"
Clean and simple.
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