wire-app

A tiny, but powerful dependency injection container for your Node.js apps

Features

• manual registering of factory fuctions and classes
• scanning directories for factory functions and classes to instantiate
• setting values and getting values
• injecting dependencies (duh)

Quick Example

const wireApp = require('wire-app');

wireApp('myCoolApp')
  .scan('./some/relative/dir')
  .scan('/some/absolute/dir')
  .register(taskRunner)
  .set('config', { my: 'values'})
  .on('error', (err) => console.error(err.message))
  .on('ready', (app) => {
    console.log(`${app.name} started!`);
    console.log(app.get('config'));
    app.get('taskRunner').run();
  });

API

The API is fluent. All functions, except get() can be chained.

wire-app(name)

Constructs a new app and returns it.

Example

wireApp('myApp')
  .on('ready', (app) => console.log(app.name)); // prints `myApp`

All other functions mentioned below are part of the 'app' API.

app.register(fn)

The register(fn) function will

1. Invoke the fn parameter and inject its dependencies
2. register it in the application context, under the function name.

The fn function should be a factory function OR a class, and must have a name.

The order you invoke the register functions does not matter. Wire-app will figure out dependency order.

The register(fn) function returns the app to provide a fluent API.

See this example

app.scan(scanPath)

Scans recursively am absolute or relative directory for exposed factory methods and/or classes. It will register them, similar to the app.register(fn) function

The app.scan(scanPath) function returns the app to provide a fluent API.

See this example

app.set(key, value)

Stores a value, under a certain key, in the application context

The value can be of any type. No dependency injection will occur

The app.set(key, value) function returns the app to provide a fluent API.

app.get(key)

Returns the value (or component) registered under the requested key.

app events

The app is an EventEmitter and will emit a few events

'ready'

This event is emitted when the whole application was wired successfully.

It emits the app as its first parameter

'error'

Will be emitted when something went wrong during the wiring phase.

Thanks

The idea of the API comes from Dieter Luypaert.