module Sinatra::ConfigFile
Sinatra::ConfigFile¶ ↑
Sinatra::ConfigFile
is an extension that allows you to load
the application's configuration from YAML files. It automatically
detects if the files contains specific environment settings and it will use
the corresponding to the current one.
You can access those options through settings
within the
application. If you try to get the value for a setting that hasn't been
defined in the config file for the current environment, you will get
whatever it was set to in the application.
Usage¶ ↑
Once you have written your configurations to a YAML file you can tell the extension to load them. See below for more information about how these files are interpreted.
For the examples, lets assume the following config.yml file:
greeting: Welcome to my file configurable application
Classic Application¶ ↑
require "sinatra" require "sinatra/config_file" config_file 'path/to/config.yml' get '/' do @greeting = settings.greeting haml :index end # The rest of your classic application code goes here...
Modular Application¶ ↑
require "sinatra/base" require "sinatra/config_file" class MyApp < Sinatra::Base register Sinatra::ConfigFile config_file 'path/to/config.yml' get '/' do @greeting = settings.greeting haml :index end # The rest of your modular application code goes here... end
Config File Format¶ ↑
In its most simple form this file is just a key-value list:
foo: bar something: 42 nested: a: 1 b: 2
But it also can provide specific environment configuration. There are two ways to do that: at the file level and at the settings level.
At the settings level (e.g. in 'path/to/config.yml'):
development: foo: development bar: bar test: foo: test bar: bar production: foo: production bar: bar
Or at the file level:
foo: development: development test: test production: production bar: bar
In either case, settings.foo
will return the environment name,
and settings.bar
will return "bar"
.
Be aware that if you have a different environment, besides development,
test and production, you will also need to adjust the
environments
setting, otherwise the settings will not load.
For instance, when you also have a staging environment:
set :environments, %w{development test production staging}
If you wish to provide defaults that may be shared among all the environments, this can be done by using one of the existing environments as the default using the YAML alias, and then overwriting values in the other environments:
development: &common_settings foo: 'foo' bar: 'bar' production: <<: *common_settings bar: 'baz' # override the default value
Public Class Methods
When the extension is registered sets the environments
setting
to the traditional environments: development, test and production.
# File lib/sinatra/config_file.rb, line 120 def self.registered(base) base.set :environments, %w[test production development] end
Public Instance Methods
Loads the configuration from the YAML files whose paths
are
passed as arguments, filtering the settings for the current environment.
Note that these paths
can actually be globs.
# File lib/sinatra/config_file.rb, line 127 def config_file(*paths) Dir.chdir(root || '.') do paths.each do |pattern| Dir.glob(pattern) do |file| $stderr.puts "loading config file '#{file}'" if logging? document = IO.read(file) document = ERB.new(document).result if file.split('.').include?('erb') yaml = config_for_env(YAML.load(document)) || {} yaml.each_pair do |key, value| for_env = config_for_env(value) set key, for_env unless value and for_env.nil? and respond_to? key end end end end end
Private Instance Methods
Given a hash
with some application configuration it returns
the settings applicable to the current environment. Note that this can
only be done when all the keys of hash
are environment names
included in the environments
setting (which is an Array of
Strings). Also, the returned config is a indifferently accessible Hash,
which means that you can get its values using Strings or Symbols as keys.
# File lib/sinatra/config_file.rb, line 152 def config_for_env(hash) if hash.respond_to? :keys and hash.keys.all? { |k| environments.include? k.to_s } hash = hash[environment.to_s] || hash[environment.to_sym] end if hash.respond_to? :to_hash indifferent_hash = Hash.new {|hash,key| hash[key.to_s] if Symbol === key } indifferent_hash.merge hash.to_hash else hash end end