Develop Reference

Why can't I use middleware in my express route?

I am creating an API, so I want to add a user system and validate access to the API.
This would be the middleware for validation:
'use strict'
const jwt = require('jwt-simple');
const moment = require('moment');
const config = require('../settings/config');
function isAuth(req, res, next) {
if (!req.headers.authotization) {
return res.status(403).send({
message: `No tiene autorizacion`
})
}
const token = req.headers.authotization.split(" ")[1];
const payload = jwt.decode(token, user, config.token.secret_token);
if (payload.exp <= moment().unix()) {
return res.status(401).send({
message: 'El token ha expirado'
})
req.user = payload.sub;
next();
}
}
module.exports = isAuth;
while this would be the route:
'use strict'
const express = require('express');
const router = express.Router();
const auth = require('../middlewares/auth');
router.get('/', auth.isAuth, (req, res) => {
res.status(200).send({
message: `Tienes acceso`
})
})
on the other hand, this is my main application settings (app.js):
const express = require('express');
const bodyParser = require('body-parser');
const morgan = require('morgan');
const app = express();
const config = require('./config')
// Middleware
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(morgan('dev'));
// Routes variables
const productRouter = require('../routes/product');
const privateRouter = require('../routes/private');
// Routes uses
app.use('/api/product', productRouter);
app.use('/private', privateRouter);
app.listen(config.app.port, err => {
if (err) throw err;
console.log(`Server listening on port ${config.app.port}`)
})
module.exports = app;
I am getting this error:
D:\api-rest-carlos-azaustre\node_modules\express\lib\router\route.js:202
throw new Error(msg);
^
Error: Route.get() requires a callback function but got a [object
Undefined]
at Route. [as get] (D:\api-rest-carlos-azaustre\node_modules\express\lib\router\route.js:202:15)
at Function.proto. [as get] (D:\api-rest-carlos-azaustre\node_modules\express\lib\router\index.js:510:19)
at Object. (D:\api-rest-carlos-azaustre\routes\private.js:6:8)
at Module._compile (internal/modules/cjs/loader.js:959:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:995:10)
at Module.load (internal/modules/cjs/loader.js:815:32)
at Function.Module._load (internal/modules/cjs/loader.js:727:14)
at Module.require (internal/modules/cjs/loader.js:852:19)
at require (internal/modules/cjs/helpers.js:74:18)
at Object. (D:\api-rest-carlos-azaustre\settings\app.js:15:23)
at Module._compile (internal/modules/cjs/loader.js:959:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:995:10)
at Module.load (internal/modules/cjs/loader.js:815:32)
at Function.Module._load (internal/modules/cjs/loader.js:727:14)
at Module.require (internal/modules/cjs/loader.js:852:19)
at require (internal/modules/cjs/helpers.js:74:18) [nodemon] app crashed - waiting for file changes before starting...
And sometimes this line is added at the top of error:
(node:3092) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 exit listeners > added to [Bus]. Use emitter.setMaxListeners() to increase limit
After reading the answers, I edit my question. I have placed only auth and not auth.isAuth and I am getting the following error:
D:\api-rest-carlos-azaustre\node_modules\express\lib\router\index.js:458
throw new TypeError('Router.use() requires a middleware function but got a ' + gettype(fn))
^
TypeError: Router.use() requires a middleware function but got a
Object
at Function.use (D:\api-rest-carlos-azaustre\node_modules\express\lib\router\index.js:458:13)
at Function. (D:\api-rest-carlos-azaustre\node_modules\express\lib\application.js:220:21)
at Array.forEach ()
at Function.use (D:\api-rest-carlos-azaustre\node_modules\express\lib\application.js:217:7)
at Object. (D:\api-rest-carlos-azaustre\settings\app.js:20:5)
at Module._compile (internal/modules/cjs/loader.js:959:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:995:10)
at Module.load (internal/modules/cjs/loader.js:815:32)
at Function.Module._load (internal/modules/cjs/loader.js:727:14)
at Module.require (internal/modules/cjs/loader.js:852:19)
at require (internal/modules/cjs/helpers.js:74:18)
at Object. (D:\api-rest-carlos-azaustre\index.js:3:13)
at Module._compile (internal/modules/cjs/loader.js:959:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:995:10)
at Module.load (internal/modules/cjs/loader.js:815:32)
at Function.Module._load (internal/modules/cjs/loader.js:727:14) [nodemon] app crashed - waiting for file changes before starting...
Does anybody know what is it due to?

module.exports = isAuth; means you're only exporting the function and nothing else. That means when you do const auth = require('../middlewares/auth');, auth is the actual function, not an object containing isAuth as a property.
So, doing router.get('/', auth, (req, res) => { should work, instead of auth.isAuth which is invalid.
Learn more about modules here: https://js.evie.dev/modules

Yes, you export the function with this code: module.exports = isAuth;
But then you call use it like this: auth.isAuth
Assuming you're doing something like const auth = require('./bin/auth.js'); or whatever
auth would be the function itself -- there will be no isAuth property.
So you should try this:
router.get('/', auth, (req, res) => {
You haven't posted your entire code, so this is just a best guess.

Conway's Game of Life Nodejs [duplicate]

Im trying to run this simple code but I m getting error all the time...I really dont know what's the problem. It seems to me very Ok...? Thanks!
var http = require(http);
console.log('Starting');
var host = '127.0.0.1';
var port = 1337;
var server = http.createServer(function(request, response){
console.log('Receive request: '+ request.url);
response.writeHead(200, {"Content-type" : "text/plain"});
response.end("Hello world");
});
server.listen(port, host, function(){
console.log('Listening: ' + host + ':' + port);
});
Console error is this:
assert.js:98
throw new assert.AssertionError({
^
AssertionError: path must be a string: path must be a string
at Module.require (module.js:362:3)
at require (module.js:380:17)
at Object.<anonymous> (/Users/yoniPacheko/PhpstormProjects/angularJS/nodeJS/server.js:9:12)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Function.Module.runMain (module.js:497:10)
at startup (node.js:119:16)
at node.js:901:3

In your first line there are quotes missing around http:
var http = require('http');

In my case, I had
var http = require('http');
var path= require('path');
As soon as I deleted the the http line, it worked for me.So, i did leave only
var path= require('path');
I was working on express,mongodb,socket.io.

Export module correctly with working functions. Node js

I want to export some module to my app.js and use it. But i catch an exception like:
'getUserFromDB isnt defined'
So, that's my app.js:
var api = require('./routes/API')
app.use(api.router)
And API.js:
const router = require('express').Router()
function getUserFromDB(login){
// some actions
}
router.get('/get-db', (req, res) => {
getUserFromDB('abcde123')
})
module.exports = {
router: router,
getUserFromDB: getUserFromDB
}
Full Stack trace:
Trace: Trace before app.use(api.router)
at Object.<anonymous> (\my-project\build\dev-server.js:74:9)
at Module._compile (module.js:570:32)
at Object.Module._extensions..js (module.js:579:10)
at Module.load (module.js:487:32)
at tryModuleLoad (module.js:446:12)
at Function.Module._load (module.js:438:3)
at Module.runMain (module.js:604:10)
at run (bootstrap_node.js:389:7)
at startup (bootstrap_node.js:149:9)
at bootstrap_node.js:502:3
ReferenceError: getUserFromDB is not defined
at NativeConnection.<anonymous> (\my-project\build\dev-server.js:65:5)
at NativeConnection.g (events.js:292:16)
at emitNone (events.js:86:13)
at NativeConnection.emit (events.js:185:7)
at open (\my-project\node_modules\mongoose\lib\connection.js:686:11)
at NativeConnection.Connection.onOpen (\my-project\node_modules\mongoose\lib\connection.js:695:5)
at \my-project\node_modules\mongoose\lib\connection.js:655:11
at \my-project\node_modules\mongoose\lib\drivers\node-mongodb-native\connection.js:71:5
at \my-project\node_modules\mongodb\lib\db.js:238:5
at Server.connectHandler (\my-project\node_modules\mongodb\lib\server.js:324:7)
at Server.g (events.js:292:16)
at emitOne (events.js:96:13)
at Server.emit (events.js:188:7)
at \my-project\node_modules\mongodb-core\lib\topologies\server.js:300:14
at \my-project\node_modules\mongodb-core\lib\connection\pool.js:469:18
at _combinedTickCallback (internal/process/next_tick.js:73:7)
at process._tickCallback (internal/process/next_tick.js:104:9)
\my-project\node_modules\mongodb\lib\server.js:327
process.nextTick(function() { throw err; })
I dont know what to do.

Please try the following
const router = require('express').Router()
function getUserFromDB(login){
// some actions
return login;
}
router.get('/get-db', (req, res) => {
res.send(getUserFromDB('abcde123'));
})
module.exports = {
router: router,
getUserFromDB: getUserFromDB
}
Change to the following in app.js
app.use('/', api.router);

const router = require('express').Router()
const getUserFromDB = function(login){
// some actions
}
router.get('/get-db', (req, res) => {
getUserFromDB('abcde123')
})
module.exports = {
router: router,
getUserFromDB: getUserFromDB
}

SyntaxError: Unexpected token >

I just installed node and tried to write and run some programs.
When I tried this example progra, I get an error.
Maybe node and npm were installed incorrectly?
Maybe some necessary packages should be install?
const http = require('http');
const net = require('net');
const url = require('url');
// Create an HTTP tunneling proxy
var proxy = http.createServer( (req, res) => {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end('okay');
});
proxy.on('connect', (req, cltSocket, head) => {
// connect to an origin server
var srvUrl = url.parse(`http://${req.url}`);
var srvSocket = net.connect(srvUrl.port, srvUrl.hostname, () => {
cltSocket.write('HTTP/1.1 200 Connection Established\r\n' + 'Proxy-agent: Node.js-Proxy\r\n' + '\r\n');
srvSocket.write(head);
srvSocket.pipe(cltSocket);
cltSocket.pipe(srvSocket);
});
});
Why does the below error appear?
var proxy = http.createServer( (req, res) => {
^
SyntaxError: Unexpected token >
at Module._compile (module.js:439:25)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Function.Module.runMain (module.js:497:10)
at startup (node.js:119:16)
at node.js:902:3 ##

Try it like this;
var requestListener = function (req, res) {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end('okay');
}
var proxy = http.createServer(requestListener);

Node Js .get() requires callback functions

This is my server.js code
var express = require('express');
feeds = require('./routes/whatshappeningfeed');
var http = require('http');
var pathname = require('path');
// Test services - to be removed
courses = require('./routes/courses');
auth = require('./routes/auth');
token = require('./routes/token');
var app = express();
app.configure(function () {
app.use(express.logger('dev')); /* 'default', 'short', 'tiny', 'dev' */
app.use(express.bodyParser());
});
app.use(function (error, req, res, next) {
if (!error) {
next();
} else {
console.error(error.stack);
res.send(500);
}
});
app.get('/me/whatshappeningfeed',feeds.getfeeds);
app.get('/courses', courses.findAll);
app.get('/courses/:id', courses.findById);
app.get('/token', token.auth);
app.get('/auth', auth.auth);
app.get('/refresh', auth.refresh);
app.listen(80);
console.log('Listening on port 80...');
this is my error message :
F:\NODE.JS\poc\node_modules\express\lib\router\index.js:291
throw new Error(msg);
^
Error: .get() requires callback functions but got a [object Undefined]
at F:\NODE.JS\poc\node_modules\express\lib\router\index.js:291:11
at Array.forEach (native)
at Router.route (F:\NODE.JS\poc\node_modules\express\lib\router\index.js:287:13)
at Router.(anonymous function) [as get] (F:\NODE.JS\poc\node_modules\express\lib\router\index.js:318:16)
at Function.app.(anonymous function) [as get] (F:\NODE.JS\poc\node_modules\express\lib\application.js:431:26)
at Object.<anonymous> (F:\NODE.JS\poc\server.js:44:5)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
When i run the node server.js file i got above error. it was working earlier. i couldn't sort out the issue. please anyone help me.

The error says it all, app.get() requires a callback function. So it means that one or more of your routes are missing a callback.
ALL of your routes should have a function(req,res), whether explicitely as in the example or in another function (see comments) :
app.get('/me/whatshappeningfeed', function(req,res){ //request, response
//then here you can define what your server should send as a response when queries for /me/whatshappeningfeed
res.send(feeds.getfeeds()); //this will send back to the browser the result of feeds.getfeeds()
});
Also, not sure if it's due to the copypaste you did, but the first semicolon require('express'); should be a comma.