homebridge-weather-plus-with-pws-sync/apis/yahoo.js

A comprehensive weather plugin for homekit with current observations, forecasts and history.

/*jshint esversion: 6,node: true,-W041: false */
"use strict";

const request = require('request'),
    converter = require('../util/converter'),
    moment = require('moment-timezone'),
    geoTz = require('geo-tz'),
    debug = require('debug')('homebridge-weather-plus');


class YahooAPI {
    constructor(location, l) {
        this.attribution = 'Powered by Yahoo';
        this.reportCharacteristics = [
            'AirPressure',
            'Condition',
            'ConditionCategory',
            'ForecastDay',
            'Humidity',
            'Temperature',
            'TemperatureMin',
            'Visibility',
            'WindDirection',
            'WindSpeed'
        ];
        this.forecastCharacteristics = [
            'Condition',
            'ConditionCategory',
            'ForecastDay',
            'Temperature',
            'TemperatureMin'
        ];
        this.forecastDays = 10;

        this.location = location;
        this.log = l;
    }

    update(forecastDays, callback) {
        debug("Updating weather with Yahoo");

        const queryUri = `https://query.yahooapis.com/v1/public/yql?q=select * from weather.forecast where u='c' AND woeid in (select woeid from geo.places(1) where text="${this.location}")&format=json`;
        request(encodeURI(queryUri), function (err, response, body) {
            if (!err) {
                // Current weather report
                const jsonObj = JSON.parse(body);
                this.parseReport(jsonObj.query.results.channel, callback);
            } else {
                this.log.error("Error retrieving weather report and forecast");
                this.log.error("Error Message: " + err);
                callback(err);
            }
        }.bind(this));
    }

    parseReport(values, callback) {
        let report = {};
        const timezone = String(geoTz(parseFloat(values.item.lat), parseFloat(values.item.long)));
        debug("Using Timezone: " + timezone);

        report.AirPressure = parseInt(values.atmosphere.pressure);
        report.Condition = values.item.condition.text;
        report.ConditionCategory = this.getConditionCategory(parseInt(values.item.condition.code));
        report.ForecastDay = moment(values.item.forecast[0].date, "DD MMM YYYY").tz(timezone).format("dddd");
        report.Humidity = parseInt(values.atmosphere.humidity);
        report.ObservationTime = moment(values.item.pubDate.substr(17), "hh:mm A [CEST]").tz(timezone).format('HH:mm:ss');
        report.Temperature = parseInt(values.item.condition.temp);
        report.TemperatureMin = parseInt(values.item.forecast[0].low);
        report.Visibility = parseFloat(values.atmosphere.visibility);
        report.WindDirection = converter.getWindDirection(parseInt(values.wind.direction));
        report.WindBearing = values.wind.direction;
        report.WindSpeed = parseFloat(values.wind.speed);

        const weather = {};
        weather.report = report;
        weather.forecasts = this.parseForecasts(values.item.forecast, timezone);
        callback(null, weather);
    }

    parseForecasts(forecastObjs, timezone) {
        let forecasts = [];
        for (let i = 0; i < forecastObjs.length; i++) {
            const values = forecastObjs[i];
            const forecast = {};
            forecast.Condition = values.text;
            forecast.ConditionCategory = this.getConditionCategory(parseInt(values.code));
            forecast.ForecastDay = moment(values.date, "DD MMM YYYY").tz(timezone).format("dddd");
            forecast.Temperature = values.high;
            forecast.TemperatureMin = values.low;
            forecasts[forecasts.length] = forecast;
        }
        return forecasts;
    }

    getConditionCategory(code) {
        // See https://developer.yahoo.com/weather/documentation.html#codes
        switch (code) {
            case 5:
            case 6:
            case 7:
            case 8:
            case 10:
            case 13:
            case 14:
            case 15:
            case 16:
            case 17:
            case 18:
            case 35:
            case 41:
            case 42:
            case 43:
            case 46:
                return 3; // snow
            case 0:
            case 1:
            case 2:
            case 3:
            case 9:
            case 11:
            case 12:
            case 37:
            case 38:
            case 39:
            case 40:
            case 45:
            case 47:
                return 2; // rain
            case 19:
            case 20:
            case 21:
            case 22:
            case 23:
            case 24:
            case 26:
            case 27:
            case 28:
            case 29:
            case 30:
                return 1; // cloudy
            case 25:
            case 31:
            case 32:
            case 33:
            case 34:
            case 36:
            case 44:
            case 3200:
                return 0;
            default:
                return 0; // clear
        }
    };
}

module.exports = {
    YahooAPI: YahooAPI
};