loopback/node_modules/asteroid-module/README.md

# asteroid-module
v0.0.1

## About

An `AsteroidModule` is an abstract class that provides a base for all asteroid modules. Its constructor takes an `options` argument provided by a `config.json`. It is also supplied with dependencies it lists on its constructor based on information in the `config.json` file.

## Example

See [resource](../resource) for an example asteroid module.

## AsteroidModule.dependencies

An asteroid module may define dependencies on other modules that can be configured in `config.json`. Eg. the [collection](../collection/lib/collection.js) module defines a [model](../model) dependency.

    Collection.dependencies = {
      model: 'model'
    }
    
A configuration then must define:

    {
      "dependencies": {
        "model": "some-model-module"
      }
    }
    
Where `some-model-module` is an existing `model` instance.

## AsteroidModule.optionsDefinition

Asteroid Modules may also describe the options they accept. This will validate the configuration and make sure users have supplied required information and in a way that the module can use to construct a working instance.

Here is an example options description for the [oracle database connection module](../connections/oracle-connection).

    // must come after `inherits()`
    OracleConnection.defineOption('hostname', 'string', {required: true});
    OracleConnection.defineOption('port', 'number', {min: 10, max: 99999});
    OracleConnection.defineOption('username', 'string');
    OracleConnection.defineOption('password', 'string');
    

### AsteroidModule.defineOption(key, type, [options])

**key** the option name given in `config.json`.

**type** must be one of:

 - string
 - boolean
 - number
 - array
 
**options** depend on the type

    {
      required: true, // options are optional by default
      min: 10, // minimum length or value
      max: 100, // max length or value
    }