While trying to deploy my node app using modulus, I encounter the error message
ReferenceError: app is not defined
at Object.<anonymous> (/mnt/app/index.js:1:63)
at Module._compile (module.js:541:32)
at Object.Module._extensions..js (module.js:550:10)
at Module.load (module.js:458:32)
at tryModuleLoad (module.js:417:12)
at Function.Module._load (module.js:409:3)
at Module.runMain (module.js:575:10)
at run (node.js:348:7)
at startup (node.js:140:9)
at node.js:463:3
index.js:
var express = require('express');
var app = express();
app.get('/hello', function(req, res) {
console.log("World!!");
})
Express.js has been installed and added to "dependencies" in package.json
"dependencies": {
"express": "^4.14.0"
}
What could be the probable cause for the Error.
app.listen(process.env.PORT || 3000);
Missed out on listening to the environment variable PORT that is causing the issue.
Related
I am trying to use socket.io on one of a simple project but when I run the same on my local machine I am getting this bug. I am not able to figure out what is going wrong my index.js is as follows
const app = require("express")();
const http = require("http").Server(app);
const io = require("socket.io")(http);
const port = process.env.PORT || 8080;
app.get("/", function(req, res) {
res.render("index.ejs");
});
http.listen(port, function() {
console.log("Listening on *:" + port);
});
The full log is here
Desktop/chat/node_modules/ws/lib/websocket.js:347
...options
^^^
SyntaxError: Unexpected token ...
at createScript (vm.js:74:10)
at Object.runInThisContext (vm.js:116:10)
at Module._compile (module.js:533:28)
at Object.Module._extensions..js (module.js:580:10)
at Module.load (module.js:503:32)
at tryModuleLoad (module.js:466:12)
at Function.Module._load (module.js:458:3)
at Module.require (module.js:513:17)
at require (internal/module.js:11:18)
at Object.<anonymous> (Desktop/chat/node_modules/ws/index.js:3:19)
My node version is 8.0
This looks like it's probably the object spread operator. If you showed the actual line of code that causes the error, we could see for sure.
You will need at least node v8.6 to get support for the object spread operator by default. Starting with node v8.21, it could be enabled via command line flags.
Im following the Getting Started Tutorial on socket.io but when i came to the point of including socket.io itself, im getting an error while running the server in the console.
What am I missing?
var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);
app.get('/', function(req, res){
res.sendFile(__dirname + '/index.html');
});
io.on('connection', function(socket){
console.log('a user connected');
});
http.listen(3000, function(){
console.log('listening on *:3000');
});
Error:
/usr/share/nginx/html/server/node_modules/socket.io/lib/index.js:177
const keysIterator = this.parentNsps.keys();
^^^^^
SyntaxError: Use of const in strict mode.
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 Module.require (module.js:364:17)
at require (module.js:380:17)
at Object.<anonymous> (/usr/share/nginx/html/server/index.js:3:10)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
I'm trying to make a connection to MongoDB using Mongoose. But it does neither throw a error nor connect to the database. Following is my code.
const express = require('express');
const app = express();
const port = process.env.PORT || 8080;
const mongoose = require('mongoose');
console.log('Hi, there!!');
mongoose.connect('mongodb://localhost:27017/db_name', (err) => {
console.log('Callback called');
if(err) throw err;
console.log('Connected to database');
})
In the above code none of the console.log inside the callback do happen. But any place outside the mongoose.connect do work like console.log('Hi, there!!')
Versions Used
express: 4.0.0
mongoose: 3.8.40
node: 7.7.3
mongodb: 3.4.0
Using mongoose: 3.8.40 I got this in the console :
{ Error: Cannot find module '../build/Release/bson'
at Function.Module._resolveFilename (module.js:470:15)
at Function.Module._load (module.js:418:25)
at Module.require (module.js:498:17)
at require (internal/module.js:20:19)
at Object.<anonymous> (/Users/kevin/nemeacreation/sites/test/stackoverflow/node_modules/bson/ext/index.js:15:10)
at Module._compile (module.js:571:32)
at Object.Module._extensions..js (module.js:580:10)
at Module.load (module.js:488:32)
at tryModuleLoad (module.js:447:12)
at Function.Module._load (module.js:439:3) code: 'MODULE_NOT_FOUND' }
js-bson: Failed to load c++ bson extension, using pure JS version
Hi, there!!
upgrading to "mongoose": "~4.4" fixed it for me. I got the answer here : https://stackoverflow.com/a/35516644/2829540
For info the latest release of mongoose is 4.10.4
I want to implement an API with POST method, But when i am starting my server then Error occured:
3450:~/Desktop/koa/ctx$ node koa2.js
/home/358/Desktop/koa/ctx/koa2.js:9
router.post('/locations', async (ctx, next) =>{
^
SyntaxError: Unexpected token (
at Object.exports.runInThisContext (vm.js:76:16)
at Module._compile (module.js:542:28)
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:394:7)
at startup (bootstrap_node.js:149:9)
at bootstrap_node.js:509:3
358#daffolap358-Latitude-3450:~/Desktop/koa/ctx$
Can anyone tell me where I am doing wrong ?
My code is :
server.js:
var Koa =require('koa');
var middleware =require('koa-router');
var logger =require('koa-logger');
var parser =require('koa-bodyparser');
const router = middleware();
const app = new Koa();
router.post('/locations', async (ctx, next) =>{
console.log("ctx");
});
app
.use(logger()) // Logs information.
.use(parser()) // Parses json body requests.
.use(router.routes()) // Assigns routes.
.use(router.allowedMethods())
app.listen(5050, () => console.log('Listening on port 5050.'));
export default app;
You are getting this error because your node version is less than 7.6.0.
It should be greater than 7.6 also Async/await support in Node 7.6 comes from updating V8, Chromium’s JavaScript engine, to version 5.5.
Check your Node version. It should be >= 7.6.0. Otherwise koa-2 and async-await pattern will not work.
I have node.js successfully installed. I have created the file
var http = require('http');
var url=require('url');
var fs=require('fs');
var io = require('socket.io');
http.createServer(function (req, res) {
fs.readFile('/var/www/nodeJS/client.html' ,
function ( err, data ) {
if ( err ) {
console.log( err );
res.writeHead(500);
return res.end( 'Error loading client.html' );
}
res.writeHead( 200 );
res.end( data );
});
}).listen(8124, '127.0.0.1');
io.listen(http);
io.sockets.on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});
The error occurs whenever I use the io object. Without io it works fine.
Error: Cannot find module 'zeparser'
at Function.Module._resolveFilename (module.js:338:15)
at Function.Module._load (module.js:280:25)
at Module.require (module.js:364:17)
at require (module.js:380:17)
at Object.<anonymous> (/var/www/nodeJS/node_modules/socket.io/node_modules/socket.io-client/node_modules/active-x-obfuscator/index.js:1:78)
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 Module.require (module.js:364:17)
After this I have also separately installed module zeparser. My default npm installation directory seems to be /usr/local/lib/node_modules.
I have set NODE_PATH as
export NODE_PATH="/usr/local/lib/node_modules"
but get the same error.
Then I tried to copy zeparser module to /var/www/nodeJS/node_modules. Then the error changes to
/var/www/nodeJS/node_modules/socket.io/lib/manager.js:104
server.on('error', function(err) {
^
TypeError: Object #<Object> has no method 'on'
at new Manager (/var/www/nodeJS/node_modules/socket.io/lib/manager.js:104:10)
at Object.exports.listen (/var/www/nodeJS/node_modules/socket.io/lib/socket.io.js:78:10)
at Object.<anonymous> (/var/www/nodeJS/app.js:35:4)
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:903:3
On your root project, do:
$ sudo npm install zeparser
It resolved the problem for me.