Skip to Content Skip to Search

Provide a better interface for accessing configuration options stored in ENV. Keys are accepted as symbols and turned into upcased strings. Nesting is provided by double underscores.

This interface mirrors what is used for ActiveSupport::EncryptedConfiguration and thus allows both to serve as interchangeable backends for Rails.app.credentials.

Examples:

require(:db_host)                                   # => ENV.fetch("DB_HOST")
require(:database, :host)                           # => ENV.fetch("DATABASE__HOST")
option(:database, :host)                            # => ENV["DATABASE__HOST"]
option(:debug, default: "true")                     # => ENV.fetch("DB_HOST") { "true" }
option(:database, :host, default: -> { "missing" }) # => ENV.fetch("DATABASE__HOST") { default.call }
Methods
K
N
O
R

Class Public methods

new()

Source: show | on GitHub 

# File activesupport/lib/active_support/env_configuration.rb, line 20
def initialize
  reload
end

Instance Public methods

keys()

Returns an array of symbolized keys from the environment variables.

Examples:

ENV["DB_HOST"] = "localhost"
ENV["DATABASE_PORT"] = "5432"

env_config = ActiveSupport::EnvConfiguration.new
env_config.keys
# => [:db_host, :database_port, ...]

Source: show | on GitHub 

# File activesupport/lib/active_support/env_configuration.rb, line 76
def keys
  @envs.keys.map { |k| k.downcase.to_sym }
end

option(*key, default: nil)

Find an upcased and double-underscored-joined string-version of the key in ENV. Returns nil if the key isn’t found. If a default value is defined, it (or its callable value) will be returned on a missing key.

Given ENV:

DB_HOST: "env.example.com"
DATABASE__HOST: "env.example.com"

Examples:

option(:db_host)                              # => "env.example.com"
option(:missing)                              # => nil
option(:missing, default: "localhost")        # => "localhost"
option(:missing, default: -> { "localhost" }) # => "localhost"

Source: show | on GitHub 

# File activesupport/lib/active_support/env_configuration.rb, line 52
def option(*key, default: nil)
  if default.respond_to?(:call)
    @envs.fetch(envify(*key)) { default.call }
  else
    @envs.fetch envify(*key), default
  end
end

reload()

Reload the cached ENV values in case any of them changed or new ones were added during runtime.

Source: show | on GitHub 

# File activesupport/lib/active_support/env_configuration.rb, line 61
def reload
  @envs = ENV.to_h
end

require(*key)

Find an upcased and double-underscored-joined string-version of the key in ENV. Raises KeyError if not found.

Given ENV:

DB_HOST: "env.example.com"
DATABASE__HOST: "env.example.com"

Examples:

require(:db_host)         # => "env.example.com"
require(:database, :host) # => "env.example.com"
require(:missing)         # => KeyError

Source: show | on GitHub 

# File activesupport/lib/active_support/env_configuration.rb, line 35
def require(*key)
  @envs.fetch envify(*key)
end