Questions tagged [node.js]
Node.js is an event-based, non-blocking, asynchronous I/O runtime that uses Google's V8 JavaScript engine and libuv library. It is used for developing applications that make heavy use of the ability to run JavaScript both on the client as well as on the server side and therefore benefit from the re-usability of code and the lack of context switching.
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Determine project root from a running node.js application
Is there a different way, other than process.cwd(), to get the pathname of the current project's root-directory. Does Node implement something like ruby's property, Rails.root,. I'm looking for ...
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CORS: Cannot use wildcard in Access-Control-Allow-Origin when credentials flag is true
I have a setup involving
Frontend server (Node.js, domain: localhost:3000) <---> Backend (Django, Ajax, domain: localhost:8000)
Browser <-- webapp <-- Node.js (Serve the app)
Browser (...
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How to solve npm error "npm ERR! code ELIFECYCLE"
I'm trying to learn react, so I have this sample code for the full-stack react voting app, and I am trying to get it to work but after running npm install followed by npm start I receive the following ...
user7037425
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11
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What does body-parser do with express?
I don't understand why we need body-parser in an Express application, as we can get data without using body-parser.
And what does it do actually and how?
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14
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node.js hash string?
I have a string that I want to hash. What's the easiest way to generate the hash in node.js?
The hash is for versioning, not security.
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6
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How can I get npm start at a different directory?
I usually cd into the app directory and then run npm start.
It is my feeling that there ought to be some way to run npm start with a path parameter. But, the npm start documentation contains no such ...
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How can I mock an ES6 module import using Jest?
I want to test that one of my ES6 modules calls another ES6 module in a particular way. With Jasmine this is super easy --
The application code:
// myModule.js
import dependency from './dependency';
...
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485
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7
answers
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Understanding passport serialize deserialize
How would you explain the workflow of Passport's serialize and deserialize methods to a layman.
Where does user.id go after passport.serializeUser has been called?
We are calling passport....
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6
answers
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How to change bower's default components folder?
I'm making a new project that uses bower from twitter. I created a component.json to maintain all my dependency like jquery. Then I run bower install that installs everything in a folder named ...
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32
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Can't run my Node.js Typescript project TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts" for /app/src/App.ts
When I try to start my app on Heroku I got the following stack trace.
It is just a basic ts.app like you see with ts-node and nodemon.
I am really interested in what the answer is going to be.
2020-05-...
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How to completely remove node.js from Windows
I uninstalled my previous version of node.js (0.8.11) and downloaded the latest, 0.10.24 from the node.js website and installed it. However, after running node --version, it still indicates that I'm ...
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How to specify local modules as npm package dependencies
I have an application which has the usual set of dependencies on third party modules (e.g. "express") specified in the package.json file under dependencies. E.g.
"express" : "...
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How can I set NODE_ENV=production on Windows?
In Ubuntu it's quite simple; I can run the application using:
$ NODE_ENV=production node myapp/app.js
However, this doesn't work on Windows. Is there a configuration file where I can set the ...
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votes
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answers
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How do I measure the execution time of JavaScript code with callbacks?
I have a piece of JavaScript code that I am executing using the node.js interpreter.
for(var i = 1; i < LIMIT; i++) {
var user = {
id: i,
name: "MongoUser [" + i + "]"
};
db.users....
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Get file name from absolute path in Nodejs?
How can I get the file name from an absolute path in Nodejs?
e.g. "foo.txt" from "/var/www/foo.txt"
I know it works with a string operation, like fullpath.replace(/.+\//, ''),
but ...
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12
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Difference between "process.stdout.write" and "console.log" in node.js?
What is the difference between "process.stdout.write" and "console.log" in node.js?
EDIT: Using console.log for a variable showed a lot of unreadable characters while using process.stdout.write ...
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467
votes
31
answers
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Command to remove all npm modules globally
Is there a command to remove all global npm modules? If not, what do you suggest?
- 20.4k
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13
answers
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How to properly upgrade node using nvm
Is it possible to upgrade node right in place, instead of manually installing the latest stable version?
I have installed node.js version 5.0 with nvm, but now I want to update it to 5.4. I'm trying ...
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Can an AWS Lambda function call another
I have 2 Lambda functions - one that produces a quote and one that turns a quote into an order.
I'd like the Order lambda function to call the Quote function to regenerate the quote, rather than just ...
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NodeJS / Express: what is "app.use"?
In the docs for the NodeJS express module, the example code has app.use(...).
What is the use function and where is it defined?
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votes
33
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NodeJS - What does "socket hang up" actually mean?
I'm building a web scraper with Node and Cheerio, and for a certain website I'm getting the following error (it only happens on this one website, no others that I try to scrape.
It happens at a ...
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npm ERR cb() never called
I have a Node.js app hosted on Heroku. Every time I do a git push heroku I get the following error:
Counting objects: 14, done.
Delta compression using up to 6 threads.
Compressing objects: 100% (12/...
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13
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Doing a cleanup action just before Node.js exits
I want to tell Node.js to always do something just before it exits, for whatever reason — Ctrl+C, an exception, or any other reason.
I tried this:
process.on('exit', function (){
console.log('...
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455
votes
3
answers
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views
What is the difference between .js and .mjs files?
I have started working on an existing project based on Node.js. I was just trying to understand the flow of execution, where I encountered with some *.mjs files. I have searched the web where I found ...
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6
answers
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How do I URl encode something in Node.js?
I want to URL encode this:
SELECT name FROM user WHERE uid = me()
Do I have to download a module for this? I already have the request module.
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votes
3
answers
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Which websocket library to use with Node.js? [closed]
Currently there is a plethora of websocket libraries for node.js, the most popular seem to be:
https://github.com/Worlize/WebSocket-Node
https://github.com/einaros/ws
https://github.com/LearnBoost/...
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13
answers
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Is there a way to automatically build the package.json file for Node.js projects
Is package.json supposed to be manually edited? Couldn't a program like npm just look through the files, see the "require" statements, and then use that to put the necessary entries in the package....
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Download a file from NodeJS Server using Express
How can I download a file that is in my server to my machine accessing a page in a nodeJS server?
I'm using the ExpressJS and I've been trying this:
app.get('/download', function(req, res){
var ...
448
votes
38
answers
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Node.js: Python not found exception due to node-sass and node-gyp
Suddenly in one of my jenkins environment build has started failing, while in local machine it seems to be working fine as i have python installed,
From the logs i was able to detect that the problem ...
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answers
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How do I debug error ECONNRESET in Node.js?
I'm running an Express.js application using Socket.io for a chat webapp
and I get the following error randomly around 5 times during 24h.
The node process is wrapped in forever and it restarts itself ...
447
votes
21
answers
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Declare multiple module.exports in Node.js
What I'm trying to achieve is to create one module that contains multiple functions in it.
module.js:
module.exports = function(firstParam) { console.log("You did it"); },
module.exports = function(...
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JavaScript, Node.js: is Array.forEach asynchronous?
I have a question regarding the native Array.forEach implementation of JavaScript: Does it behave asynchronously?
For example, if I call:
[many many elements].forEach(function () {lots of work to do})...
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How to get a URL parameter in Express?
I am facing an issue on getting the value of tagid from my URL: localhost:8888/p?tagid=1234.
Help me out to correct my controller code. I am not able to get the tagid value.
My code is as follows:
...
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answers
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What's the difference between process.cwd() vs __dirname?
What's the difference between
console.log(process.cwd())
and
console.log(__dirname);
I've seen both used in similar contexts.
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13
answers
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Node.js throws "btoa is not defined" error
In my node.js application I did an npm install btoa-atob so that I could use the btoa() and atob() functions which are native in client-side javascript but for some reason weren't included in node. ...
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votes
45
answers
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Get local IP address in Node.js
I have a simple Node.js program running on my machine and I want to get the local IP address of a PC on which my program is running. How do I get it with Node.js?
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votes
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answers
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req.body empty on posts
All of a sudden this has been happening to all my projects.
Whenever I make a post in nodejs using express and body-parser req.body is an empty object.
var express = require('express')
var ...
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votes
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answers
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views
What is the "__v" field in Mongoose
I'm using Mongoose version 3 with MongoDB version 2.2. I've noticed a __v field has started appearing in my MongoDB documents. Is it something to do with versioning? How is it used?
- 8,862
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Start script missing error when running npm start
I'm receiving this error when trying to debug my node application using the npm start command.
Error:
npm ERR! Windows_NT 6.3.9600
npm ERR! argv "C:\\Program Files\\nodejs\\\\node.exe" "...
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npm - how to show the latest version of a package
How do I use npm to show the latest version of a module? I am expecting something like npm --latest express to print out v3.0.0.
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How to set NODE_ENV to production/development in OS X
For use in express.js environments. Any suggestions?
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votes
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answers
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Mongoose: findOneAndUpdate doesn't return updated document
Below is my code
var mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/test');
var Cat = mongoose.model('Cat', {
name: String,
age: {type: Number, default: 20},
...
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Node update a specific package
I want to update my Browser-sync without updating all my node packages. How can I achieve this? My current version of Browser-sync does not have the Browser-sync GUI :(
├─┬ [email protected]
│ ├── ...
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Can pm2 run an 'npm start' script
Is there a way for pm2 to run an npm start script or do you just have to run pm2 start app.js
So in development
npm start
Then in production with pm2 you would run something like
pm2 start 'npm start'...
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426
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Ignore invalid self-signed ssl certificate in node.js with https.request?
I'm working on a little app that logs into my local wireless router (Linksys) but I'm running into a problem with the router's self-signed ssl certificate.
I ran wget 192.168.1.1 and get:
ERROR: ...
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17
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Why does npm install say I have unmet dependencies?
I have a node package. When I run npm install from the package root, it installs a bunch of things, but then prints several error messages that look like this:
npm WARN unmet dependency /Users/...
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How do I consume the JSON POST data in an Express application
I'm sending the following JSON string to my server.
(
{
id = 1;
name = foo;
},
{
id = 2;
name = bar;
}
)
On the server I have this.
app.post('...
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votes
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answers
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Async/Await Class Constructor
At the moment, I'm attempting to use async/await within a class constructor function. This is so that I can get a custom e-mail tag for an Electron project I'm working on.
customElements.define('e-...
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How to Polyfill node core modules in webpack 5
webpack 5 no longer do auto-polyfilling for node core modules.
How to fix it please?
BREAKING CHANGE: webpack < 5 used to include polyfills for node.js core modules by default.
This is no longer ...
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votes
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receiving error: 'Error: SSL Error: SELF_SIGNED_CERT_IN_CHAIN' while using npm
I am using npm v1.0.104/node 0.6.12 on ubuntu - I am receiving the error copied below while attempting to install any new modules via npm (I tested socket.io earlier using http, not https though & ...
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