fooduse-monitor.js

const MiniDb = require('./minidb');
const FeedParser = require('feedparser');
const request = require('request');
const config = require('./config');

const DiscordChannelSync = require("./discord-channel-sync");

class FooduseMonitor {
    static start() {
        if (!config.discord_fooduse_channel) {
            // Fooduse integration is disabled (no channel configured)
            return;
        }

        // Db init
        this.db = new MiniDb('fooduse-monitor');

        // Db read
        this.lastAnnouncedVideoGuid = null;

        try {
            const dbRecord = this.db.get("fooduse");
            if (dbRecord) {
                this.lastAnnouncedVideoGuid = dbRecord.lastAnnouncedVideoGuid;
            }
        } catch (e) { }

        // Loop
        this.interval = setInterval(() => {
            this.doCheck();
        }, FooduseMonitor.YT_CHECK_INTERVAL_SECS * 1000);

        this.doCheck();
    }

    static doCheck() {
        let fpReq = request(this.feedUrl);
        let fp = new FeedParser();

        fpReq.on('error', (err) => {
            console.error('[Fooduse]', 'Could not check Youtube feed (request error).', err);
        });

        fpReq.on('response', function (res) {
            let stream = this;

            if (res.statusCode === 200) {
                stream.pipe(fp);
            }
        });

        fp.on('error', (err) => {
            console.error('[Fooduse]', 'Could not check Youtube feed (parser error).', err);
        });

        let highestDate = null;
        let highestItem = null;

        fp.on('readable', function() {
            let stream = this;
            let meta = this.meta;
            let item;

            while (item = stream.read()) {
                let itemDate = Date.parse(item.pubdate);

                if (highestDate == null || itemDate > highestItem) {
                    highestItem = item;
                    highestDate = itemDate;
                }
            }
        });

        fp.on('end', function() {
            if (highestItem) {
                FooduseMonitor.handleHighestItem(highestItem);
            }
        });
    }

    static handleHighestItem(rssItem) {
        let lastGuid = this.lastAnnouncedVideoGuid;
        let thisGuid = rssItem.guid;

        if (lastGuid && lastGuid === thisGuid) {
            return;
        }

        console.debug('[Fooduse]', `Found new video to announce: ${rssItem.title} [${rssItem.guid}]`);

        this.db.put("fooduse", { lastAnnouncedVideoGuid: thisGuid });
        this.lastAnnouncedVideoGuid = thisGuid;
        this.doAnnounce(rssItem);
    }

    static doAnnounce(rssItem) {
        this.targetChannels = DiscordChannelSync.getChannelList(global.discordJsClient,
            config.discord_fooduse_channel, false);

        let emojiTxtBob = global.getServerEmoji("BOB_USE", true);
        let formattedMessage = `${rssItem.link} ${emojiTxtBob}`;

        for (let i = 0; i < this.targetChannels.length; i++) {
            let targetChannel = this.targetChannels[i];

            if (targetChannel) {
                try {
                    targetChannel.send(formattedMessage);
                } catch (err) {
                    console.error('[Fooduse]', 'Announce error:', err);
                }
            }
        }
    }

    static get feedUrl() {
        let cacheBuster = Date.now();
        return `${FooduseMonitor.YT_FEED_BASE_URL}?channel_id=${FooduseMonitor.YT_CHANNEL_ID}&orderby=published&_cacheBust=${cacheBuster}`;
    }
}

FooduseMonitor.YT_CHANNEL_ID = "UCCuIpl5564hhP8Qpucvu7RA";
FooduseMonitor.YT_FEED_BASE_URL = "https://www.youtube.com/feeds/videos.xml";
FooduseMonitor.YT_CHECK_INTERVAL_SECS = 10 * 60;

module.exports = FooduseMonitor;