NodeJS module development
Module
There are a lot of module provided by many people.
Basically, nodejs package are managed by npm.
If you want to develop something in common or additional useful codes, what should we do?
Nodejs provides module development
Simple Example
Add simple module
This is directory structure
yourproject |- my_module.js |- my_module2.js
my_module.js and my_module2.js are module sources
Type1
var myModule = {};
myModule.hello = function() {
console.log('Hello');
};
myModule.double = function(num) {
return num * 2;
};
module.exports = myModule;
Type2
exports.helloworld = function() {
console.log('Hello World!');
};
exports.add = function(a, b) {
return a + b;
};
Test
How to use module?
node test.js
var my_module = require('my_module');
my_module.hello();
console.log(my_module.double(5));
var my_module2 = require('my_module2');
my_module2.helloworld();
console.log(my_module2.add(5, 6));
Run
node test.js
Package like module
Create package.json in your project
|- test.js
|- node_moduels
|- my_module3
|- index.js
|- package.json
|- lib
|- submodule.js
I create module directory whose name is my_module3
my_module3 has main source(index.js), package.json and lib directory.
lib has dependency codes.
module main source code(index.js)
console.log("call index.js");
module.exports = require('./lib/submodule.js');
package.json
package.json is package information
{
"name" : "my_module3",
"version" : "0.0.1",
"description" : "module3",
"main" : "index.js",
"author" : "atmarkplant",
"license" : "MIT"
}
Dependency code(submodule.js)
var submodule = {};
submodule.helloJapan = function() {
console.log("Hello, Japan!");
};
module.exports = submodule;
Test(test.js)
var my_module = require('my_module3');
my_module.helloJapan();
Run!
node test.js