npm i -S yeps-logger debug
const App = require('yeps');
const logger = require('yeps-logger');
const error = require('yeps-error');
const app = new App();
app.all([
error(),
logger(),
]);
You can use any system for logging. By default it's console.
const log4js = require('log4js');
app.all([
logger(log4js),
]);
Try: