web midi, if it ever works

index.js

midi = null
port = null
getMidi(function(e, m){
	midi = m
  console.log(midi)
  var iter = midi.inputs.values()
  port = iter.next()
  console.log(port)
  port.value.onmidimessage = function(e,d){
  	console.log(e, d)
  }
})
 
function getMidi(cb){
  if (midi){
    process.nextTick(function(){
      cb(null, midi)
    })
  } else if (window.navigator.requestMIDIAccess) {
    window.navigator.requestMIDIAccess().then(function(res){
      midi = res
      cb(null, midi)
    }, cb)
  } else {
    process.nextTick(function(){
      cb('Web MIDI API not available')
    })
  }
}