fetchUTC.js

/**
 * Returns UNIX time in milliseconds.
 */
async function fetchUTC({
    timeout = 10000,
    shouldCompensate = true // subtracts half of the xhr request time from the time extracted from page
}={}) {

    const servers = [
        {
            name: 'trigger-community',
            fetchArgs: [
                'https://trigger-community.sundayschoolonline.org/unixtime.php'
            ],
            getUTCFromResponse: async res => {
                if (res.status !== 200) throw `Unhandled Status (${res.status})`;
                const replyJSON = await res.json();
                const utc = replyJSON.unixtime * 1000;
                return utc;
            }
        },
        {
            name: 'CurrentTimestamp.com',
            fetchArgs: [
                'http://currenttimestamp.com/'
            ],
            getUTCFromResponse: async res => {
                if (res.status !== 200) throw new Error(`Unhandled Status (${res.status})`);

                const replyHTML = await res.text();

                const utcMatch = /current_time = (\d+);/.exec(replyHTML);
                if (!utcMatch) throw new Error('Extraction Failed');

                const utc = utcMatch[1] * 1000;
                return utc;
            }
        },
        {
            name: 'convert-unix-time.com',
            fetchArgs: [
                'http://convert-unix-time.com/'
            ],
            getUTCFromResponse: async res => {
                if (res.status !== 200) throw `Unhandled Status (${res.status})`;

                const replyHTML = await res.text();
                const utcMatch = /currentTimeLink.*?(\d{10,})/.exec(replyHTML);
                if (!utcMatch) throw new Error('Extraction Failed');

                const utc = utcMatch[1] * 1000;
                return utc;
            }
        }
    ];

    const errors = [];

    for (const { fetchArgs, name, getUTCFromResponse } of servers) {
        try {
            const fetchStart = Date.now();
            const res = await Promise.race([
                fetch(...fetchArgs),
                new Promise((_, reject) => setTimeout(()=>reject('Timed Out'), timeout))
            ]);
            const fetchDuration = Date.now() - fetchStart;
            const fetchDurationHalf = Math.round(fetchDuration / 2);

            let utc = await getUTCFromResponse(res);

            if (shouldCompensate) utc -= fetchDurationHalf;

            return utc;
        } catch(err) {
            errors.push(`Server "${name}" Error: ${err.message}`);
        }
    }

    throw new Error(errors.join('\n'));
}

fetchUTC().then(console.log).catch(console.warn);