EnvConfig

Allows easy definition of application configs based on env vars. Supports string values and all types that have a constructor new(value : String). Allows defining converters for more complex types (see usage). Inspired by JSON::Serializable.

Installation

Add this to your application's shard.yml:

dependencies:
  env_config:
    github: jreinert/env_config.cr

Usage

require "env_config"
require "uri"

module MyApp
  def self.config
    @@config ||= Config.new(ENV, prefix: "MY_APP")
  end

  class Config
    include EnvConfig

    getter server : ServerConfig

    @[EnvConfig::Setting(key: "db")]
    getter database : DatabaseConfig

    class ServerConfig
      include EnvConfig

      getter host : String = "localhost"
      getter port : Int32 = 3000
      getter reuse_port : Bool
    end

    class DatabaseConfig
      include EnvConfig

      getter host : String = "localhost"
      getter port : Int32 = 6543
      getter name : String
      getter username : String?
      getter password : String?

      def uri
        URI.parse("postgres://#{host}:#{port}/#{name}").tap do |uri|
          username.try(&uri.username=)
          password.try(&uri.password=)
        end
      end
    end
  end
end

$> MY_APP_SERVER_HOST=0.0.0.0 MY_APP_SERVER_REUSE_PORT=1 MY_APP_DB_NAME=my_app bin/my_app

Development

If you find bugs or type conversions missing please let me know or fix/add support for them yourself. Pull requests welcome!

Contributing

1. Fork it (https://github.com/jreinert/env_config.cr/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• jreinert Joakim Reinert - creator, maintainer