Class: ActiveSupport::CombinedConfiguration

Inherits:
Object
  • Object
show all
Defined in:
activesupport/lib/active_support/combined_configuration.rb

Overview

Allows for configuration keys to be pulled from multiple backends. Keys are pulled in first-found order from the configuration backends that the combined configuration has been initialized with.

This is used by Rails to offer a unified API for fetching credentials from both ENV and the encrypted file. You can access this through Rails.app.creds within a Rails application.

Instance Method Summary collapse

Constructor Details

#initialize(*configurations) ⇒ CombinedConfiguration

Returns a new instance of CombinedConfiguration.



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# File 'activesupport/lib/active_support/combined_configuration.rb', line 12

def initialize(*configurations)
  @configurations = configurations
end

Instance Method Details

#inspect ⇒ Object

:nodoc:



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# File 'activesupport/lib/active_support/combined_configuration.rb', line 68

def inspect # :nodoc:
  "#<#{self.class.name}:#{'%#016x' % (object_id << 1)} keys=#{keys.inspect}>"
end

#keys ⇒ Object

Returns a unique array of all symbolized keys available across all backend configurations.

Examples of Rails-configured access:

ENV["DB_HOST"] = "localhost"
Rails.app.credentials # has keys [:secret_key_base, :aws]

Rails.app.creds.keys
# => [:db_host, :secret_key_base, :aws]



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# File 'activesupport/lib/active_support/combined_configuration.rb', line 64

def keys
  @configurations.flat_map(&:keys).uniq
end

#option(*key, default: nil) ⇒ Object

Find singular or nested keys across all backends. If no backend holds the key, nil is returned. If a default value is defined, it (or its callable value) will be returned on a missing key.

Examples:

option(:db_host)                             # => ENV["DB_HOST"] || Rails.app.credentials.option(:db_host)
option(:database, :host)                     # => ENV["DATABASE__HOST"] || Rails.app.credentials.option(:database, :host)
option(:database, :host, default: "missing") # => ENV["DATABASE__HOST"] || Rails.app.credentials.option(:database, :host) || "missing"
option(:database, :host, default: -> { "missing" }) # => ENV["DATABASE__HOST"] || Rails.app.credentials.option(:database, :host) || "missing"



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# File 'activesupport/lib/active_support/combined_configuration.rb', line 40

def option(*key, default: nil)
  @configurations.each do |config|
    value = config.option(*key)
    return value unless value.nil?
  end

  default.respond_to?(:call) ? default.call : default
end

#reload ⇒ Object

Reload the cached values for all of the backend configurations.



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# File 'activesupport/lib/active_support/combined_configuration.rb', line 50

def reload
  @configurations.each { |config| config.try(:reload) }
end

#require(*key) ⇒ Object

Find singular or nested keys across all backends. If no backend holds the key, it raises KeyError.

Examples of Rails-configured access:

require(:db_host)         # => ENV["DB_HOST"] || Rails.app.credentials.require(:db_host)
require(:database, :host) # => ENV["DATABASE__HOST"] || Rails.app.credentials.require(:database, :host)

Raises:

  • (KeyError) 


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# File 'activesupport/lib/active_support/combined_configuration.rb', line 22

def require(*key)
  @configurations.each do |config|
    value = config.option(*key)
    return value unless value.nil?
  end

  raise KeyError, "Missing key: #{key.inspect}"
end