dashy/server.js

93 lines
3.6 KiB
JavaScript

/**
* Note: The app must first be built (yarn build) before this script is run
* This is the main entry point for the application, a simple server that
* runs some checks, and then serves up the app from the ./dist directory
* Also includes some routes for status checks/ ping and config saving
* */
/* Include required node dependencies */
const serveStatic = require('serve-static');
const connect = require('connect');
const util = require('util');
const dns = require('dns');
const os = require('os');
const bodyParser = require('body-parser');
/* Include helper functions and route handlers */
const pingUrl = require('./services/ping'); // Used by the status check feature, to ping services
const saveConfig = require('./services/save-config'); // Saves users new conf.yml to file-system
const printMessage = require('./services/print-message'); // Function to print welcome msg on start
const rebuild = require('./services/rebuild-app'); // A script to programmatically trigger a build
require('./src/utils/ConfigValidator'); // Include and kicks off the config file validation script
/* Checks if app is running within a container, from env var */
const isDocker = !!process.env.IS_DOCKER;
/* Checks env var for port. If undefined, will use Port 80 for Docker, or 4000 for metal */
const port = process.env.PORT || (isDocker ? 80 : 4000);
/* Attempts to get the users local IP, used as part of welcome message */
const getLocalIp = () => {
const dnsLookup = util.promisify(dns.lookup);
return dnsLookup(os.hostname());
};
/* Gets the users local IP and port, then calls to print welcome message */
const printWelcomeMessage = () => {
getLocalIp().then(({ address }) => {
const ip = address || 'localhost';
console.log(printMessage(ip, port, isDocker)); // eslint-disable-line no-console
});
};
/* Just console.warns an error */
const printWarning = (msg, error) => {
console.warn(`\x1b[103m\x1b[34m${msg}\x1b[0m\n`, error || ''); // eslint-disable-line no-console
};
/* A middleware function for Connect, that filters requests based on method type */
const method = (m, mw) => (req, res, next) => (req.method === m ? mw(req, res, next) : next());
try {
connect()
.use(bodyParser.json())
// Serves up the main built application to the root
.use(serveStatic(`${__dirname}/dist`))
// During build, a custom page will be served before the app is available
.use(serveStatic(`${__dirname}/public`, { index: 'default.html' }))
// This root returns the status of a given service - used for uptime monitoring
.use('/ping', (req, res) => {
try {
pingUrl(req.url, async (results) => {
await res.end(results);
});
} catch (e) {
printWarning(`Error running ping check for ${req.url}\n`, e);
}
})
// POST Endpoint used to save config, by writing conf.yml to disk
.use('/config-manager/save', method('POST', (req, res) => {
try {
saveConfig(req.body, (results) => {
res.end(results);
});
} catch (e) {
res.end(JSON.stringify({ success: false, message: e }));
}
}))
// GET endpoint to trigger a build, and respond with success status and output
.use('/config-manager/rebuild', (req, res) => {
rebuild().then((response) => {
res.end(JSON.stringify(response));
}).catch((response) => {
res.end(JSON.stringify(response));
});
})
// Finally, initialize the server then print welcome message
.listen(port, () => {
try { printWelcomeMessage(); } catch (e) { printWarning('Dashy is Starting...'); }
});
} catch (error) {
printWarning('Sorry, a critical error occurred ', error);
}