How to use Node's debug module (Windows)? - windows

Question

I am trying to figure out what is wrong with my sessions (using express-session), and I found that it uses the debug module. However, I can't seem to enable the debug messages. It says, debugging needs to be enabled through the DEBUG environment variable, but I can't seem to get it to run.
The tutorial in the README has this picture:
Under Windows I get "DEBUG is not a command for the command-line".
So I tried setting the environment variable explicitly using:
process.env.DEBUG = "*";
and still nothing.
What am I doing wrong?

Answer 1

As Traveling Tech Guy suggested in the comment, in a Windows command prompt, the proper syntax is:
set DEBUG=* & npm start
Obviously you can replace npm start with whatever command you need to launch your Node.js app. Just be sure to use the set command and don't forget the & between that command and the one launching your Node.js app!

Answer 2

If you are used to powershell, I recommend this setup in your package.json, then you can just run npm start so you don't type all that out every time.
"scripts": {
"start": "#powershell $env:DEBUG='*,-express:router*' ; node app.js"
},

Answer 3

Install debug package with npm inside the node application
npm install debug
Open a powershell and then
$Env:DEBUG="name_to_call"
node path_to_js_to_execute.js
Inside your pgm
var debug = require('debug')('name_to_call');

Answer 4

Firstly you need to install the debug module using
"npm install debug --save"
you will see that the following lane has been added to you package.json (which has all the npm modules charged to your proyect)
then you need to add this to import the module to the file in which you want to run the debug
var debug = require('debug')('name_to_call');
now we have to just put the message we want to write, for example hello
var debug = require('debug')('name_to_call');
debug('Hello');
(try pasting the code above directly to a file)
Now we just need to start the windows server with DEBUG, to do so we are going to use the npm package cross-env that will make easier to set an ENV variable across any operating system (platform agnostic)
npm install cross-env
Change the package.json and add the following under the scripts section
"start-server": "cross-env DEBUG=name_to_call node server.js"
Now to start the server just run the following in a command line (from the directory in which your project is) and you are good to go
npm run start-server

Answer 5

In Babun a windows shell, I run,
npm
npm install debug --save
babun
DEBUG=http node app
app.js
var app = express();
var debug = require('debug')('http');
var http = require('http').Server(app);
var server = http.listen(app.get('port'), function() {
debug('listening on port ' + server.address().port);
});
works like a charme for me.

Answer 6

Windows Command:
set DEBUG=* & node ./app.js
PowerShell:
$env:DEBUG='*'; node app.js
Terminal/WSL (Ubuntu):
DEBUG=* node ./app.js