Script to show NetAtmo weather on Onion Omega OLED Display

weather-config.json

{
    "clientId": "",
    "clientSecret": "",
    "username": "",
    "password": ""
}

weather.js

var https = require('https'),
    fs = require('fs'),
    querystring = require('querystring'),
    oledAddon = require("/usr/bin/oled-exp-addon");

function writeLine(text) {
    var trimmed = text.substring(0, 21);
    if (trimmed.length < 21) {
        trimmed += "\\n";
    }
    oledAddon.write(trimmed);
}

function updateModule(module) {
    var date = new Date(module.dashboard_data.time_utc * 1000);
    writeLine(module.module_name + ' @ ' + date.toLocaleTimeString());
    writeLine('  ' + module.dashboard_data.Temperature + ' C - ' + module.dashboard_data.Humidity + ' %');
}

function updateDevice(device) {
    var date = new Date(device.dashboard_data.time_utc * 1000);
    writeLine(device.module_name + ' @ ' + date.toLocaleTimeString());
    writeLine('  ' + device.dashboard_data.Temperature + ' C - ' + device.dashboard_data.Humidity + ' %');
    writeLine('  ' + device.dashboard_data.CO2 + ' ppm');

    for (var i = 0; i < device.modules.length; i++) {
        updateModule(device.modules[i]);
    }
}

function invert(callback) {
    var invertFile = '/tmp/weather-invert';
    fs.exists(invertFile, function(exists) {
        if (exists) {
            fs.unlink(invertFile);
        } else {
            fs.closeSync(fs.openSync(invertFile, 'w'));
        }
        callback(exists ? 1 : 0);
    });
}

function updateDisplay(devices) {
    oledAddon.init();
    invert(function(mode) {
        oledAddon.setDisplayMode(mode);
    });
    oledAddon.write('--- N e t A t m o ---');

    for (var i = 0; i < devices.length; i++) {
        updateDevice(devices[i]);
    }
}

function getStationsData(token) {
    console.log('getting data for ' + token);
    https.get('https://api.netatmo.com/api/getstationsdata?access_token=' + token, function(res) {
        console.log('status: ' + res.statusCode);
        if (res.statusCode === 200) {
            var body = "";
            res.on('data', function(chunk) {
                body += chunk;
            });
            res.on('end', function() {
                var data = JSON.parse(body);
                if (data) {
                    if (data.body) {
                        if (data.body.devices) {
                            updateDisplay(data.body.devices);
                        }
                    }
                }
            });
        } else {
            console.log('error getting data: ' + res.statusCode);
        }
    });
}

function authenticate(data, success) {
    // Build the post string from an object
    var post_data = querystring.stringify({
        "client_id": data.clientId,
        "client_secret": data.clientSecret,
        "username": data.username,
        "password": data.password,
        "grant_type": "password",
        "scope": "read_station"
    });
    console.log(post_data);

    // An object of options to indicate where to post to
    var post_options = {
        host: 'api.netatmo.com',
        port: '443',
        path: '/oauth2/token',
        method: 'POST',
        headers: {
            'Content-Type': 'application/x-www-form-urlencoded',
        }
    };

    console.log('authenticating ' + data.username);
    var req = https.request(post_options, function(res) {
        if (res.statusCode === 200) {
            var body = "";
            res.on('data', function(chunk) {
                body += chunk;
            });
            res.on('end', function() {
                var data = JSON.parse(body);
                if (data) {
                    var token = data.access_token;
                    if (token) {
                        console.log('token: ' + token)
                        success(token);
                    }
                }
            });
        } else {
            console.log('error authenticating: ' + res.statusCode);
        }
    });

    req.write(post_data);
    req.end();
}

fs.readFile('weather-config.json', function(err, contents) {
    if (err) throw err;

    var data = JSON.parse(contents);
    console.log('username: ' + data.username);
    authenticate(data, function(token) {
        getStationsData(token);
    });
});