cloudron-box/syslog/server.js

'use strict';

exports = module.exports = {
    start,
    stop
};

const LOG_FILENAME = 'app.log';

const assert = require('assert'),
    debug = require('debug')('syslog:server'),
    fs = require('fs'),
    net = require('net'),
    path = require('path'),
    parser = require('nsyslog-parser'),
    util = require('util');

let server = null;

async function start(options) {
    assert.strictEqual(typeof options, 'object');
    assert.strictEqual(typeof options.logFolder, 'string');

    debug('==========================================');
    debug('          Cloudron Syslog Daemon          ');
    debug('==========================================');

    server = net.createServer();

    server.on('error', function (error) {
        console.error(`server error: ${error}`);
    });

    server.on('connection', function (socket) {
        socket.on('data', function (msg) {
            const info = parser(msg.toString());

            if (!info || !info.appName) return debug('Ignore unknown app log:', msg.toString());

            // remove line breaks to avoid holes in the log file
            // we do not ignore empty log lines, to allow gaps for potential ease of readability
            const message = info.message.replace(/\n/g, '');

            const filePath = path.join(options.logFolder, info.appName);
            const fileName = path.join(filePath, LOG_FILENAME);

            try {
                fs.mkdirSync(filePath, { recursive: true });
                fs.appendFileSync(fileName, info.ts.toISOString() + ' ' + message + '\n');
            } catch (error) {
                console.error(error);
            }
        });

        socket.on('error', function (error) {
            console.error(`socket error: ${error}`);
        });
    });

    await fs.promises.rm('/home/yellowtent/platformdata/logs/syslog.sock', { force: true });
    await util.promisify(server.listen.bind(server))('/home/yellowtent/platformdata/logs/syslog.sock');

    debug('Listening on syslog.sock');
}

async function stop() {
    if (!server) return;
    await util.promisify(server.close.bind(server))();
    server = null;
}