node-webmidi-shim
Shim for the Web MIDI API based on node-midi
This project implements the Web MIDI API (https://webaudio.github.io/web-midi-api/) in Node.
It allows for creating MIDI applications that will both work in the browser (currently Google Chrome), as well as in a Node-environment.
Requirements
Tested with Node 4, 5 and 6. Uses ES6.
Usage
At a prompt:
$ npm install webmidi-shim
Then, in a node repl:
var r = require('webmidi-shim')
r.requestMIDIAccess().then(ma => {
// send a note-on C3 velocity 64 to the first connected MIDI output device
ma.outputs.values().next().value.send([0x90, 48, 64],1000)
// log any incoming messages from the first connected MIDI input device
ma.inputs.values().next().value.onmidimessage = console.log
})
Similar projects
It's sorta like https://github.com/cwilso/WebMIDIAPIShim, which however is dependent on the proprietary Jazz-Plugin (http://jazz-soft.net/download/Jazz-Plugin), which is limited to x86 architectures.
This shim is based node-midi, which is again based on on RtMidi, which bridges to the various OS-specific MIDI APIs, so this shim can run on several architectures.
Examples
My specific use-case is getting a sequencer app (https://github.com/grav/seq) running both in Chrome and on a Raspberry Pi. Currently, it's web-only, but the goal is to produce a version running headlessly on an RPi
Current status
Still not feature complete - but doesn't crash randomly anymore, since inputs are now running in child processes.
Notable missing features are:
- get notified when MIDI setup changes (
onstatechange) - various attributes of the MIDI devices
- the concept of Ports
Acknowledements
- ryanlaws for suggesting spawning inputs in child processes