How can I edit on my server files without restarting nodejs when i want to see the changes?

Question

I\'m trying to setup my own nodejs server, but I\'m having a problem. I can\'t figure out how to see changes to my application without restarting it. Is there a way to edit

Answer 1

if you would like to reload a module without restarting the node process, you can do this by the help of the watchFile function in fs module and cache clearing feature of require:

Lets say you loaded a module with a simple require:

var my_module = require('./my_module');

In order to watch that file and reload when updated add the following to a convenient place in your code.

fs.watchFile(require.resolve('./my_module'), function () {
    console.log("Module changed, reloading...");
    delete require.cache[require.resolve('./my_module')]
    my_module = require('./my_module');
});

If your module is required in multiple files this operation will not affect other assignments, so keeping module in a global variable and using it where it is needed from global rather than requiring several times is an option. So the code above will be like this:

global.my_module = require ('./my_module');
//..
fs.watchFile(require.resolve('./my_module'), function () {
    console.log("Module changed, reloading...");
    delete require.cache[require.resolve('./my_module')]
    global.my_module = require('./my_module');
});

Answer 2

Check out Node-Supervisor. You can give it a collection of files to watch for changes, and it restarts your server if any of them change. It also restarts it if it crashes for some other reason.

"Hot-swapping" code is not enabled in NodeJS because it is so easy to accidentally end up with memory leaks or multiple copies of objects that aren't being garbage collected. Node is about making your programs accidentally fast, not accidentally leaky.

EDIT, 7 years after the fact: Disclaimer, I wrote node-supervisor, but had handed the project off to another maintainer before writing this answer.

Answer 3

You can also use the tool PM2. Which is a advanced production process tool for node js. http://pm2.keymetrics.io/