Loopback: How to stop a console command? - loopbackjs

Question

I am running a loopback command through the command line.
the script is as follows:
const app = require('../../server/server');
let acquireToken = function() {
app.stop();
};
acquireToken();
However this does not seem to work as stop() is not a function. So I have added this in the server.js file:
'use strict';
let loopback = require('loopback');
let boot = require('loopback-boot');
let app = module.exports = loopback();
let winston = require('./winston');
app.start = function() {
// start the web server
return app.listen(function() {
app.emit('started');
let baseUrl = app.get('url').replace(/\/$/, '');
winston.info('Web server listening at: %s', baseUrl);
if (app.get('loopback-component-explorer')) {
let explorerPath = app.get('loopback-component-explorer').mountPath;
winston.info('Browse your REST API at %s%s', baseUrl, explorerPath);
}
});
};
let server;
app.stop = () => {
server.close();
}
// Bootstrap the application, configure models, datasources and middleware.
// Sub-apps like REST API are mounted via boot scripts.
boot(app, __dirname, function(err) {
if (err) throw err;
// start the server if `$ node server.js`
if (require.main === module)
server = app.start();
});
module.exports = app;
But require.main == module is preventing this from working as this gives me the following:
TypeError: Cannot read property 'close' of undefined
What is the recommended way of making this work?

Answer 1

Your question is a bit misleading because you're trying to stop an express object returned from a require call, so a more accurate question is
How do I start and stop a listening loopback app from another script?
In server.js change app.start = function() to app.start = function(cb) and add if (cb) {cb()}; to the end.
'use strict';
let loopback = require('loopback');
let boot = require('loopback-boot');
let app = module.exports = loopback();
let winston = require('./winston');
app.start = function(cb) {
// start the web server
return app.listen(function() {
app.emit('started');
let baseUrl = app.get('url').replace(/\/$/, '');
winston.info('Web server listening at: %s', baseUrl);
if (app.get('loopback-component-explorer')) {
let explorerPath = app.get('loopback-component-explorer').mountPath;
winston.info('Browse your REST API at %s%s', baseUrl, explorerPath);
}
if (cb) cb();
});
};
let server;
app.stop = () => {
server.close();
}
// Bootstrap the application, configure models, datasources and middleware.
// Sub-apps like REST API are mounted via boot scripts.
boot(app, __dirname, function(err) {
if (err) throw err;
// start the server if `$ node server.js`
if (require.main === module)
server = app.start();
});
module.exports = app;
And for your file which starts and stops loopback
// Setup loopback, but don't start the server
const app = require('./server');
// Define our callback function
let acquireToken = function() {
app.server.close();
console.log('closed');
};
// Hold onto the listener object so we can stop it later and start the server with the callback which executes after startup.
app.server = app.start(acquireToken);