Node.js project naming conventions for files & folders

What are the naming conventions for files and folders in a large Node.js project?

Should I capitalize, camelCase, or under-score?

Ie. is this considered valid?

project-name
    app
        controllers
            someThings.js
            users.js
        models
                someThing.js
                user.js
        views
            some-things
                index.jade
            users
                logIn.jade
                signUp.jade
    ...

After some years with node, I can say that there are no conventions for the directory/file structure. However most (professional) express applications use a setup like:

/
  /bin - scripts, helpers, binaries
  /lib - your application
  /config - your configuration
  /public - your public files
  /test - your tests

An example which uses this setup is nodejs-starter.

I personally changed this setup to:

/
  /etc - contains configuration
  /app - front-end javascript files
    /config - loads config
    /models - loads models
  /bin - helper scripts
  /lib - back-end express files
    /config - loads config to app.settings
    /models - loads mongoose models
    /routes - sets up app.get('..')...
  /srv - contains public files
  /usr - contains templates
  /test - contains test files

In my opinion, the latter matches better with the Unix-style directory structure (whereas the former mixes this up a bit).

I also like this pattern to separate files:

lib/index.js

var http = require('http');
var express = require('express');

var app = express();

app.server = http.createServer(app);

require('./config')(app);

require('./models')(app);

require('./routes')(app);

app.server.listen(app.settings.port);

module.exports = app;

lib/static/index.js

var express = require('express');

module.exports = function(app) {

  app.use(express.static(app.settings.static.path));

};

This allows decoupling neatly all source code without having to bother dependencies. A really good solution for fighting nasty Javascript. A real-world example is nearby which uses this setup.

Update (filenames):

Regarding filenames most common are short, lowercase filenames. If your file can only be described with two words most JavaScript projects use an underscore as the delimiter.

Update (variables):

Regarding variables, the same "rules" apply as for filenames. Prototypes or classes, however, should use camelCase.

Update (styleguides):

• https://github.com/feross/standard
• https://github.com/airbnb/javascript

Use kebab-case for all package, folder and file names.

Why?

You should imagine that any folder or file might be extracted to its own package some day. Packages cannot contain uppercase letters.

> New packages must not have uppercase letters in the name. https://docs.npmjs.com/files/package.json#name

Therefore, camelCase should never be used. This leaves snake_case and kebab-case.

kebab-case is by far the most common convention today. The only use of underscores is for internal node packages, and this is simply a convention from the early days.

There are no conventions. There are some logical structure.

The only one thing that I can say: Never use camelCase file and directory names. Why? It works but on Mac and Windows there are no different between someAction and some action. I met this problem, and not once. I require'd a file like this:

var isHidden = require('./lib/isHidden');

But sadly I created a file with full of lowercase: lib/ishidden.js. It worked for me on mac. It worked fine on mac of my co-worker. Tests run without errors. After deploy we got a huge error:

Error: Cannot find module './lib/isHidden'

Oh yeah. It's a linux box. So camelCase directory structure could be dangerous. It's enough for a colleague who is developing on Windows or Mac.

So use underscore (_) or dash (-) separator if you need.

Based on 'Google JavaScript Style Guide'

> File names must be all lowercase and may include underscores (_) or > dashes (-), but no additional punctuation. Follow the convention that > your project uses. Filenames’ extension must be .js.

Node.js doesn't enforce any file naming conventions (except index.js). And the Javascript language in general doesn't either. You can find dozens of threads here which suggest camelCase, hyphens and underscores, any of which work perfectly well. So its up to you. Choose one and stick with it.

According to me: For files, use lower camel case if module.exports is an object, I mean a singleton module. This is also applicable to JSON files as they are also in a way single ton. Use upper camel case if module.exports returns a constructor function where it acts like a class.

For folders use short names. If there is need to have multiple words, let it be completely lower case separated by "-" so that it works across all platforms consistently.

Most people use camelCase in JS. If you want to open-source anything, I suggest you to use this one :-)

Here is my idea

project-name
    app
        controllers
            somethings.controller.js
            user-story.controller.js
            users.controller.js
        models
                something.model.js
                user.model.js
        views
            some-things
                index.view.jade
            users
                login.view.jade
                signup.view.jade