moved route filter to route directory.

system/route/filter.php

@@ -0,0 +1,53 @@
+<?php namespace System\Route;
+
+class Filter {
+
+	/**
+	 * The loaded route filters.
+	 *
+	 * @var array
+	 */
+	public static $filters;
+
+	/**
+	 * Call a set of route filters.
+	 *
+	 * @param  string  $filter
+	 * @param  array   $parameters
+	 * @param  bool    $override
+	 * @return mixed
+	 */
+	public static function call($filters, $parameters = array(), $override = false)
+	{
+		if (is_null(static::$filters))
+		{
+			static::$filters = require APP_PATH.'filters'.EXT;
+		}
+
+		// --------------------------------------------------------------
+		// Filters can be comma-delimited, so spin through each one.
+		// --------------------------------------------------------------
+		foreach (explode(', ', $filters) as $filter)
+		{
+			if ( ! isset(static::$filters[$filter]))
+			{
+				throw new \Exception("Route filter [$filter] is not defined.");						
+			}
+
+			$response = call_user_func_array(static::$filters[$filter], $parameters);
+
+			// --------------------------------------------------------------
+			// If overriding is set to true and the filter returned a
+			// response, return that response. 
+			//
+			// Overriding allows for convenient halting of the request
+			// flow for things like authentication, CSRF protection, etc.
+			// --------------------------------------------------------------
+			if ( ! is_null($response) and $override)
+			{
+				return $response;
+			}
+		}
+	}
+
+}