Thursday, November 08, 2012

Node.JS on the Raspberry Pi

Most of this procedure is taken from a posting on Github by Sander Tolsma. His post is a little bit old and some of the steps he included can be skipped because the versions of things have become better synchronized. So very briefly, here is what to do, assuming you've successfully booted into Raspbian.

$ sudo apt-get install git-core build-essential
$ # IIRC, build-essential is already present on Raspbian
$ git clone https://github.com/joyent/node.git
$ cd node
$ git checkout v0.8.14-release
$ #             ^^^^^^ update to most recent stable version
$ ./configure
$ make        # this takes a while
$ sudo make install

Voila, you're done. Type "node" at the Linux prompt and you'll get Node's ">" prompt. Then you can type in JavaScript and watch it run interactively, or you can create a file of JavaScript and run it.

pi@raspberrypi ~ $ cat > foo.js
for (var i = 0; i < 3; i++)
  console.log(i);
^D
pi@raspberrypi ~ $ node foo.js
0
1
2

I'd like to import events from hardware so that they can take handlers, just like DOM event handlers running on a browser. One approach would be to run an HTTP server in Node and set up endpoints for the events I want to handle. That sounds like quite a bit of overhead for hardware events.

Alternatively, I could do what looks like the right thing, involving eventfd and its cohorts. I need to dig into the Node source code to see how to do that, and do more research in general.

1 comment:

city said...

thanks for sharing.