Calculate running time
create a middleware
var uuid = require('uuid'),
common = require('../../lib/common');
/**
* @TODO:
* - move middleware to ignition?
*/
module.exports = function logRequest(req, res, next) {
var startTime = Date.now(),
requestId = req.get('X-Request-ID') || uuid.v1();
function logResponse() {
res.responseTime = (Date.now() - startTime) + 'ms';
req.requestId = requestId;
req.userId = req.user ? (req.user.id ? req.user.id : req.user) : null;
if (req.err && req.err.statusCode !== 404) {
common.logging.error({req: req, res: res, err: req.err});
} else {
common.logging.info({req: req, res: res});
}
res.removeListener('finish', logResponse);
res.removeListener('close', logResponse);
}
res.on('finish', logResponse);
res.on('close', logResponse);
next();
};
Error Handling
use middleware
use next() to pass error to error handler. If want to end the process, need return next().
Error-handling middleware always takes four arguments. You must provide four arguments to identify it as an error-handling middleware function. Even if you don’t need to use the next object, you must specify it to maintain the signature.
const app = require('express')();
app.get('*', function(req, res, next) {
// Reporting async errors *must* go through `next()`
setImmediate(() => { next(new Error('woops')); });
});
app.use(function(error, req, res, next) {
// Will get here
res.json({ message: error.message });
});
app.listen(3000);
Application
Keystone: cms
Ghost: web editor
Feathers.js: real-time application