Mastering JavaScript

Chapter 5
The Node.js server will have something as follows:
var nodeServer = new BasicServer();
nodeServer = nodeServer.decorate('serveNode');
nodeServer = nodeServer.decorate('3000');
nodeServer.init();
There are several ways in which the decorator pattern is implemented in JavaScript.
We will discuss a method where the pattern is implemented by a list and does not
rely on inheritance or method call chain:
//Implement BasicServer that does the bare minimum
function BasicServer() {
this.pid = 1;
console.log("Initializing basic Server");
this.decorators_list = []; //Empty list of decorators
}
//List of all decorators
BasicServer.decorators = {};
//Add each decorator to the list of BasicServer's decorators
//Each decorator in this list will be applied on the BasicServer
instance
BasicServer.decorators.reverseProxy = {
init: function(pid) {
console.log("Started Reverse Proxy");
return pid + 1;
}
};
BasicServer.decorators.servePHP = {
init: function(pid) {
console.log("Started serving PHP");
return pid + 1;
}
};
BasicServer.decorators.serveNode = {
init: function(pid) {
console.log("Started serving Node");
return pid + 1;
}
};
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