Anyway Config
Rails/Ruby plugin/application configuration tool which allows you to load parameters from different sources: YAML, Rails secrets, environment.
Allows you to easily follow the twelve-factor application principles and adds zero complexity to your development process.
Libraries using Anyway Config:
Installation
1) Adding to a gem:
# my-cool-gem.gemspec
Gem::Specification.new do |spec|
...
spec.add_dependancy "anyway_config", "~> 1.0"
...
end
2) Adding to your project:
# Gemfile
gem "anyway_config", "~> 1.0"
3) Install globally:
$ gem install anyway_config
Usage
Pre-defined configuration
Create configuration class:
require 'anyway'
module MyCoolGem
class Config < Anyway::Config
attr_config user: 'root', password: 'root', host: 'localhost'
end
end
attr_config
creates accessors and default values. If you don't need default values just write:
attr_config :user, :password, host: 'localhost'
Then create an instance of the config class and use it:
module MyCoolGem
def self.config
@config ||= Config.new
end
end
MyCoolGem.config.user #=> 'root'
Customize name
By default, Anyway Config uses the namespace (the outer module name) as the config name, but you can set it manually:
module MyCoolGem
class Config < Anyway::Config
config_name :cool
attr_config user: 'root', password: 'root', host: 'localhost', options: {}
end
end
Dynamic configuration
You can also create configuration objects without pre-defined schema (just like Rails.application.config_for
but more powerful):
# load data from config/my_app.yml, secrets.my_app (if using Rails), ENV["MYAPP_*"]
config = Anyway::Config.for(:my_app)
Using with Rails
Your config will be filled up with values from the following sources (ordered by priority from low to high):
RAILS_ROOT/config/my_cool_gem.yml
(for the currentRAILS_ENV
, supportsERB
)Rails.application.secrets.my_cool_gem
ENV['MYCOOLGEM_*']
.
Using with Ruby
By default, Anyway Config is looking for a config YAML at ./config/<config-name>.yml
. You can override this setting
through special environment variable – 'MYGEM_CONF' – containing the path to the YAML file.
Environmental variables work the same way as with Rails.
Config clear and reload
There are #clear
and #reload
functions on your config (which do exactly what they state).
Rails.application.config_for
vs Anyway::Config.for
Rails 4.2 introduced new feature: Rails.application.config_for
. It looks very similar to
Anyway::Config.for
, but there are some differences:
Feature | Rails | Anyway Config |
---|---|---|
load data from config/app.yml |
yes | yes |
load data from secrets |
no | yes |
load data from environment | no | yes |
return Hash with indifferent access | no | yes |
support ERB within config/app.yml |
yes | yes* |
raise errors if file doesn't exist | yes | no |
*make sure that ERB is loaded
But the main advantage of Anyway::Config is that it can be used without Rails!)
How to set env vars
Environmental variables for your config should start with your config name, uppercased and underscore-free.
For example, if your module is called "MyCoolGem" then the env var "MYCOOLGEM_PASSWORD" is used as config.password
.
Environment variables are type-casted (case-insensitive).
Examples:
"True"
,"t"
and"yes"
totrue
;"False"
,"f"
and"no"
tofalse
;"nil"
and"null"
tonil
(do you really need it?);"123"
to 123 and"3.14"
to 3.14.
Anyway Config supports nested (hashed) env variables. Just separate keys with double-underscore.
For example, "MYCOOLGEM_OPTIONS__VERBOSE" is parsed as config.options.verbose
.
Array values are also supported:
# Suppose ENV["MYCOOLGEM_IDS"] = '1,2,3'
config.ids #=> [1,2,3]
If you want to provide a text-like env variable which contains commas then wrap it into quotes:
MYCOOLGEM="Nif-Nif, Naf-Naf and Nouf-Nouf"
Contributing
- Fork it
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Add some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create a new Pull Request