My Node.js modules these days

example.js

// Short module explanation             // Something to gather my thoughts
//                                      // I think this looks cool.
                                        //
module.exports = the_exported_function  // Modules are a function. Always.
                                        //
module.exports.extra = extra            // Additional API entry points if
module.exports.other = other            // desired.
                                        //
var util = require('util')              // Other packages from npm or core
var assert = require('assert')          // No comma-first due to lots of
var whatever = require('whatever')      // churn in Git.
                                        //
var foo = require('./foo')              // Modules within this package
var bar = require('./bar')              //
                                        //
var ENABLE_BUGS = false                 // Globals in the module, upper-case
  , MODE = 'production'                 // I like comman-first. YMMV.
                                        // (Two blank lines)
                                        //
function the_exported_function() {      // The primary API entry point, either
}                                       // a function or constructor.
                                        //
function extra() {                      // Some other optional API function
}                                       //
                                        //
function other() {                      // Some other optional API function
}                                       //
                                        // (Two blank lines)
                                        //
function main() {                       // Optional main function for CLI
}                                       // execution.
                                        //
if(require.main === module)             // Run main() if this module is
  main()                                // executed rather than required.

@jhs Can you say a bit about why modules should always be functions? How might you structure, for instance, Underscore.js to work under that suggestion?

also, you can leverage that last line like this:

// IF RUN DIRECTLY via node <filename>.js
if(require.main === module) {
  // do stuff here 
}
// otherwise its a module
else {
  module.exports = the_exported_function
}

@jugglinmike underscore is a function. For example, you could do either _(arr).find(predicate) or _.find(arr, predicate) interchangeably

i sometimes come up with this pattern:

module.exports = function(confs, deps){
  var dep1 = deps.dep1 || require('dep1')
     , dep2 =  //and so on
  var conf1 = //same with confs
  return function theFunctionThatDoTheJob(/*args*/){ /*fancy code here*/}
}

//some static stuff here
var MYCONST = 'foo'
function fancyHelperStuff(){}

this way i'm ready for dependency injection. i don't do DI for all dependencies, but if i want to, i can. so i.e. the user can provide mikeals request as http client module or i just fall back to native one. same here for different EventEmitter implementations and so on.

@greelgorke Yes, for that I use my package, Defaultable: https://github.com/nodejitsu/defaultable