outfield

Async configuration loader/validator built on top of shortstop

Usage

``js
var joi = require('joi'); // used for validations

var config = require('outfield');

var schema = {
DATABASE_URL: {
description: 'The connection string for the Database',
validate: joi.string().uri(),
default: 'postgres://postgres@localhost:5432/testdb'
}
};

config(schema, function(err, env){
// err if validation or resolution fails

env.DATABASE_URL; // 'postgres://postgres@localhost:5432/testdb'
});
`

API

$3

The only method. Takes a schema object, optional options, and a callback.
The schema is parsed, resolved, populated and validated and the callback
is called with an error or an object containing the environment. Everything
is resolved using the process.env with fallbacks to resolving the resolve
property using shortstop and then the default property.

#### schema

The schema object is composed of keys for your environment. Each key is
assigned a definition object comprised of 4 keywords.
Instead of a definiton object, you can nest keys; __However, if there are
any keywords, the nesting will be ignored.__

* description __(optional)__ - Used to describe your configuration. Not currently used internally, but allows for extra features in the future.
* validate __(required)__ - Used to validate and convert values to proper types. Accepts joi validations.
* default __(optional)__ - Used to provide a default to your environment if the key can't be resolved or isn't in process.env.
* resolve __(optional)__ - String that resolves to a registered shortstop handler. __Note: No shortstop handlers are registered by default. They must be added using the options object.__

#### options

The options object allows you to register shortstop handlers and adjust joi configuration.

* handlers __(optional)__ - Object containing key/handler pairs of shortstop handlers to register in the shortstop instance. The handler can be an array of handlers, each will be registered as the key.
* joi __(optional)__ - Object containing joi configuration overrides. __Note: In this module, allowUnknown is defaulted to true, abortEarly is defaulted to false and presence is defaulted to required instead of the joi defaults.__

#### callback(err, env)

The callback function is called once all resolution and validation is done. If resolution or
validation fails, the callback will be called with an error. If everything succeeds, the env
argument will be an object containing the fully resolved environment. Also, the property
NODE_ENV will be resolved to development if undefined in the environment and the properties
development, production, test and staging will be resolved to booleans based on NODE_ENV.
__Note: environment variables will not be resolved if allowUnknown is false` in the joi configuration.__

License

MIT