ServletsFilter style request chaining.

This is very simple single file module, but provides a nice structure for webapps allowing you to introduce configurable aspects to each request.

The chain is configured in code, you can externalize it if you need.

Usage:

First load a set of filters

var attributesFilter = 		require("../server/attributes-filter"),
	logRequestFilter = 	require("../server/log-request-filter")
	serverHeaderFilter = 	require("../server/server-header-filter"),
	notModifiedFilter = 	require("../server/not-modified-filter"),
	routerFilter = 		require("../server/router");

Create an ordered array of the filters and pass it to the FilterChain constructor 

var chainModules = [
	attributesFilter, 
	logRequestFilter, 
	serverHeaderFilter,
	notModifiedFilter,
	routerFilter
];

var chain = new FilterChain(chainModules);


Then, in a server start, the chain with it's execute() method, passing the request and response.


http.createServer(function(request, response) {
	// N.B a typical router should be in the chain
	//router.route(request, response);

	chain.execute(request, response);
	
}).listen(8000);


That's it, nothing special, but a usefull design pattern.


Filters look identical to Java Servlets filters.

var parse = require('url').parse;

filter = function(request, response, chain) {
	
	var url = parse(request.url);
	console.log(request.method + " " + url.pathname);
	
	chain.doFilter(request, response);
	
};

exports.filter = filter;

You must export a function called "filter", but the module can do any thing else as well.