Raspbian

IoT.js landed in Raspbian

Following previous efforts to deploy iotjs on RaspberryPi 0, I am happy to announce that IoTjs 1.0 landed in Debian, and was sync’d to Raspbian for ArmHF and Ubuntu as well.

While the package is targeting the next distro release, it can be easily installed on current versions by adding a couple of config files for “APT pinning”.

If you haven’t set up Raspbian 9, just dump the current Raspbian image to SDcard (for the record I used version 2018-03-13-raspbian-stretch-lite)

Setup IoT.js on Raspbian

Boot your Pi. To keep track of changes in /etc/, let’s install etckeeper:

sudo apt-get update
sudo apt-get install etckeeper

Upgrade current packages:

sudo apt-get upgrade
sudo apt-get dist-upgrade

Declare the current release as default source:

cat<<EOT | sudo tee /etc/apt/apt.conf.d/50raspi
APT::Default-Release "stretch";
EOT

Then add a repo file for the next release:

cat /etc/apt/sources.list | sed 's/stretch/buster/g' | sudo tee /etc/apt/sources.list.d/raspi-buster.list

Unless you want to test the upcoming release, it maybe be safer to avoid upgrading all packages yet. In other words, we prefer that only IotJs should be available from this “not yet supported” repo.

cat<<EOT | sudo tee /etc/apt/preferences.d/raspi-buster.pref
Package: *
Pin: release n=buster
Pin-Priority: -10
EOT

cat<<EOT | sudo tee /etc/apt/preferences.d/iotjs.pref
Package: iotjs
Pin: release n=buster
Pin-Priority: 1
EOT

Now iotjs 1.0-1 should appear as available for installation:

sudo apt-get update ; apt-cache search iotjs
iotjs - Javascript Framework for Internet of Things

apt-cache policy iotjs
iotjs:
  Installed: (none)
  Candidate: 1.0-1
  Version table:
     1.0-1 1
        -10 http://raspbian.raspberrypi.org/raspbian buster/main armhf Packages

Let’s install it:

sudo apt-get install iotjs
man iotjs

Try it:

Even if version 1.0 is limited in compared to the development branch, you can start by using the http module which is enabled by default (not https).

To illustrate this, when I investigated “air quality monitoring” for a TizenRT+IoT.js demo I found out that OpenWeatherMap is collecting and publishing “Carbon Monoxide” Data, so let’s try their REST API.

Create a file, example.js for example, that contains:

var http = require('http');

var location = '48,-1';
var datetime = 'current';

//TODO: replace with your openweathermap.org personal key
var api_key = 'fb3924bbb699b17137ab177df77c220c';

var options = {
  hostname: 'api.openweathermap.org',
  port: 80,
  path: '/pollution/v1/co/' + location + '/' + datetime + '.json?appid=' + api_key,
};

// workaround bug
options.headers = {
  host: options.hostname
}

http.request(options, function (res) {
  receive(res, function (data) {
    console.log(data);
  });
}).end();

function receive(incoming, callback) {
  var data = '';

  incoming.on('data', function (chunk) {
    data += chunk;
  });

  incoming.on('end', function () {
    callback ? callback(data) : '';
  });
}

And just run it:

iotjs example.js
{"time":"2018-03-27T02:24:33Z","location":{"latitude":47.3509,"longitude":-0.9081},"data":[{"precision":-4.999999987376214e-07,"pressure":1000,"value":1.5543508880000445e-07}
(...)

You can then use this to do things such as update a map or raise an alert on anything useful, or try to rebuild master branch.

LICENSE: CC-BY-SA-4.0

• https://creativecommons.org/licenses/by-sa/4.0/

Article originally published at:

• https://s-opensource.org/#