apiObjectを作る時のutility

example.js

'use strict'
var handle = require('./handle')
var events = require('events')
var assign = require('object-assign')

var list = []
var api  = assign({}, events.EventEmitter.prototype)

// API
// handle.call(
//     targetObject
//   , methods
//   , sourceObject
// )
handle.call(api, {
    put: 'push'
  , get: 'shift'
}, list)

// handle.call(...) is
// api.put = function (value) {
//     return list.push(value)
// }
// api.get = function () {
//     return list.shift()
// }

api.on('change', function () {
    console.log(api.get())
})

api.put({hello: 'hello world'})
api.emit('change')

handle.js

'use strict'
module.exports = function handle (pair, she) {
    var me = this
    Object.keys(pair).forEach(function (myMethod) {
        var herMethod = pair[myMethod]
        if ('function' === typeof she[herMethod]) {
            me[myMethod] = function () {
                return she[herMethod].apply(she, arguments)
            }
        }
    })
}