[lib] Split Bridge/Cache/Format into one file per class

The files have grown to a size where it is necessary to search
for a class in a file. This commit splits the content into one
file per class. RSS-Bridge will require implementations and
the implementations will require (once) the interfaces.

12 files changed, 796 insertions, 793 deletions

diff --git a/lib/Bridge.php b/lib/Bridge.php
index 72734df1..bacb77a0 100644
--- a/lib/Bridge.php
+++ b/lib/Bridge.php
@@ -1,4 +1,5 @@
 <?php
+require_once(__DIR__ . '/BridgeInterface.php');
 class Bridge {
 
     static protected $dirBridge;
@@ -101,658 +102,3 @@ EOD;
         }
     }
 }
-
-interface BridgeInterface {
-    public function collectData();
-    public function getCacheDuration();
-    public function getName();
-    public function getURI();
-}
-
-abstract class BridgeAbstract implements BridgeInterface {
-
-    const NAME = 'Unnamed bridge';
-    const URI = '';
-    const DESCRIPTION = 'No description provided';
-    const MAINTAINER = 'No maintainer';
-    const PARAMETERS = array();
-
-    public $useProxy = true;
-
-    protected $cache;
-    protected $items = array();
-    protected $inputs = array();
-    protected $queriedContext = '';
-
-    protected function returnError($message, $code){
-        throw new \HttpException($message, $code);
-    }
-
-    protected function returnClientError($message){
-        $this->returnError($message, 400);
-    }
-
-    protected function returnServerError($message){
-        $this->returnError($message, 500);
-    }
-
-    /**
-    * Return items stored in the bridge
-    * @return mixed
-    */
-    public function getItems(){
-        return $this->items;
-    }
-
-    protected function validateTextValue($value, $pattern = null){
-        if(!is_null($pattern)){
-            $filteredValue = filter_var($value, FILTER_VALIDATE_REGEXP,
-                array('options' => array(
-                    'regexp' => '/^' . $pattern . '$/'
-                ))
-            );
-        } else {
-            $filteredValue = filter_var($value);
-        }
-
-        if($filteredValue === false)
-            return null;
-
-        return $filteredValue;
-    }
-
-    protected function validateNumberValue($value){
-        $filteredValue = filter_var($value, FILTER_VALIDATE_INT);
-
-        if($filteredValue === false && !empty($value))
-            return null;
-
-        return $filteredValue;
-    }
-
-    protected function validateCheckboxValue($value){
-        $filteredValue = filter_var($value, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
-
-        if(is_null($filteredValue))
-            return null;
-
-        return $filteredValue;
-    }
-
-    protected function validateListValue($value, $expectedValues){
-        $filteredValue = filter_var($value);
-
-        if($filteredValue === false)
-            return null;
-
-        if(!in_array($filteredValue, $expectedValues)){ // Check sub-values?
-            foreach($expectedValues as $subName => $subValue){
-                if(is_array($subValue) && in_array($filteredValue, $subValue))
-                    return $filteredValue;
-            }
-            return null;
-        }
-
-        return $filteredValue;
-    }
-
-    protected function validateData(&$data){
-        if(!is_array($data))
-            return false;
-
-        foreach($data as $name=>$value){
-            $registered = false;
-            foreach(static::PARAMETERS as $context=>$set){
-                if(array_key_exists($name,$set)){
-                    $registered = true;
-                    if(!isset($set[$name]['type'])){
-                        $set[$name]['type']='text';
-                    }
-
-                    switch($set[$name]['type']){
-                    case 'number':
-                        $data[$name] = $this->validateNumberValue($value);
-                        break;
-                    case 'checkbox':
-                        $data[$name] = $this->validateCheckboxValue($value);
-                        break;
-                    case 'list':
-                        $data[$name] = $this->validateListValue($value, $set[$name]['values']);
-                        break;
-                    default:
-                    case 'text':
-                        if(isset($set[$name]['pattern'])){
-                            $data[$name] = $this->validateTextValue($value, $set[$name]['pattern']);
-                        } else {
-                            $data[$name] = $this->validateTextValue($value);
-                        }
-                        break;
-                    }
-
-                    if(is_null($data[$name])){
-                        echo 'Parameter \'' . $name . '\' is invalid!' . PHP_EOL;
-                        return false;
-                    }
-                }
-            }
-
-            if(!$registered)
-                return false;
-        }
-
-        return true;
-    }
-
-    protected function setInputs(array $inputs, $queriedContext){
-        // Import and assign all inputs to their context
-        foreach($inputs as $name => $value){
-            foreach(static::PARAMETERS as $context => $set){
-                if(array_key_exists($name, static::PARAMETERS[$context])){
-                    $this->inputs[$context][$name]['value'] = $value;
-                }
-            }
-        }
-
-        // Apply default values to missing data
-        $contexts = array($queriedContext);
-        if(array_key_exists('global', static::PARAMETERS)){
-            $contexts[] = 'global';
-        }
-
-        foreach($contexts as $context){
-            foreach(static::PARAMETERS[$context] as $name => $properties){
-                if(isset($this->inputs[$context][$name]['value'])){
-                    continue;
-                }
-
-                $type = isset($properties['type']) ? $properties['type'] : 'text';
-
-                switch($type){
-                case 'checkbox':
-                    if(!isset($properties['defaultValue'])){
-                        $this->inputs[$context][$name]['value'] = false;
-                    } else {
-                        $this->inputs[$context][$name]['value'] = $properties['defaultValue'];
-                    }
-                    break;
-                case 'list':
-                    if(!isset($properties['defaultValue'])){
-                        $firstItem = reset($properties['values']);
-                        if(is_array($firstItem)){
-                            $firstItem = reset($firstItem);
-                        }
-                        $this->inputs[$context][$name]['value'] = $firstItem;
-                    } else {
-                        $this->inputs[$context][$name]['value'] = $properties['defaultValue'];
-                    }
-                    break;
-                default:
-                    if(isset($properties['defaultValue'])){
-                        $this->inputs[$context][$name]['value'] = $properties['defaultValue'];
-                    }
-                    break;
-                }
-            }
-        }
-
-        // Copy global parameter values to the guessed context
-        if(array_key_exists('global', static::PARAMETERS)){
-            foreach(static::PARAMETERS['global'] as $name => $properties){
-                if(isset($inputs[$name])){
-                    $value = $inputs[$name];
-                } elseif (isset($properties['value'])){
-                    $value = $properties['value'];
-                } else {
-                    continue;
-                }
-                $this->inputs[$queriedContext][$name]['value'] = $value;
-            }
-        }
-
-        // Only keep guessed context parameters values
-        if(isset($this->inputs[$queriedContext])){
-            $this->inputs = array($queriedContext => $this->inputs[$queriedContext]);
-        } else {
-            $this->inputs = array();
-        }
-    }
-
-    protected function getQueriedContext(array $inputs){
-        $queriedContexts=array();
-        foreach(static::PARAMETERS as $context=>$set){
-            $queriedContexts[$context]=null;
-            foreach($set as $id=>$properties){
-                if(isset($inputs[$id]) && !empty($inputs[$id])){
-                    $queriedContexts[$context]=true;
-                }elseif(isset($properties['required']) &&
-                    $properties['required']===true){
-                    $queriedContexts[$context]=false;
-                    break;
-                }
-            }
-        }
-
-        if(array_key_exists('global',static::PARAMETERS) &&
-            $queriedContexts['global']===false){
-            return null;
-        }
-        unset($queriedContexts['global']);
-
-        switch(array_sum($queriedContexts)){
-        case 0:
-            foreach($queriedContexts as $context=>$queried){
-                if (is_null($queried)){
-                    return $context;
-                }
-            }
-            return null;
-        case 1: return array_search(true,$queriedContexts);
-        default: return false;
-        }
-    }
-
-    /**
-    * Defined datas with parameters depending choose bridge
-    * Note : you can define a cache with "setCache"
-    * @param array array with expected bridge paramters
-    */
-    public function setDatas(array $inputs){
-        if(!is_null($this->cache)){
-            $this->cache->prepare($inputs);
-            $time = $this->cache->getTime();
-            if($time !== false && (time() - $this->getCacheDuration() < $time)){
-                $this->items = $this->cache->loadData();
-                return;
-            }
-        }
-
-        if(empty(static::PARAMETERS)){
-            if(!empty($inputs)){
-                $this->returnClientError('Invalid parameters value(s)');
-            }
-
-            $this->collectData();
-            if(!is_null($this->cache)){
-                $this->cache->saveData($this->getItems());
-            }
-            return;
-        }
-
-        if(!$this->validateData($inputs)){
-            $this->returnClientError('Invalid parameters value(s)');
-        }
-
-        // Guess the paramter context from input data
-        $this->queriedContext = $this->getQueriedContext($inputs);
-        if(is_null($this->queriedContext)){
-            $this->returnClientError('Required parameter(s) missing');
-        } elseif($this->queriedContext === false){
-            $this->returnClientError('Mixed context parameters');
-        }
-
-        $this->setInputs($inputs, $this->queriedContext);
-
-        $this->collectData();
-
-        if(!is_null($this->cache)){
-            $this->cache->saveData($this->getItems());
-        }
-    }
-
-    function getInput($input){
-        if(!isset($this->inputs[$this->queriedContext][$input]['value'])){
-            return null;
-        }
-        return $this->inputs[$this->queriedContext][$input]['value'];
-    }
-
-    public function getName(){
-        return static::NAME;
-    }
-
-    public function getURI(){
-        return static::URI;
-    }
-
-    public function getCacheDuration(){
-        return 3600;
-    }
-
-    public function setCache(\CacheAbstract $cache){
-        $this->cache = $cache;
-    }
-
-    public function debugMessage($text){
-        if(!file_exists('DEBUG')) {
-            return;
-        }
-
-        $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 3);
-        $calling = $backtrace[2];
-        $message = $calling['file'] . ':'
-        . $calling['line'] . ' class '
-        . get_class($this) . '->'
-        . $calling['function'] . ' - '
-        . $text;
-
-        error_log($message);
-    }
-
-    protected function getContents($url
-    , $use_include_path = false
-    , $context = null
-    , $offset = 0
-    , $maxlen = null){
-        $contextOptions = array(
-            'http' => array(
-                'user_agent' => ini_get('user_agent')
-            ),
-        );
-
-        if(defined('PROXY_URL') && $this->useProxy){
-            $contextOptions['http']['proxy'] = PROXY_URL;
-            $contextOptions['http']['request_fulluri'] = true;
-
-            if(is_null($context)){
-                $context = stream_context_create($contextOptions);
-            } else {
-                $prevContext=$context;
-                if(!stream_context_set_option($context, $contextOptions)){
-                    $context = $prevContext;
-                }
-            }
-        }
-
-        if(is_null($maxlen)){
-            $content = @file_get_contents($url, $use_include_path, $context, $offset);
-        } else {
-            $content = @file_get_contents($url, $use_include_path, $context, $offset, $maxlen);
-        }
-
-        if($content === false)
-            $this->debugMessage('Cant\'t download ' . $url);
-
-        return $content;
-    }
-
-    protected function getSimpleHTMLDOM($url
-    , $use_include_path = false
-    , $context = null
-    , $offset = 0
-    , $maxLen = null
-    , $lowercase = true
-    , $forceTagsClosed = true
-    , $target_charset = DEFAULT_TARGET_CHARSET
-    , $stripRN = true
-    , $defaultBRText = DEFAULT_BR_TEXT
-    , $defaultSpanText = DEFAULT_SPAN_TEXT){
-      $content = $this->getContents($url, $use_include_path, $context, $offset, $maxLen);
-      return str_get_html($content
-      , $lowercase
-      , $forceTagsClosed
-      , $target_charset
-      , $stripRN
-      , $defaultBRText
-      , $defaultSpanText);
-    }
-}
-
-/**
- * Extension of BridgeAbstract allowing caching of files downloaded over http.
- * TODO allow file cache invalidation by touching files on access, and removing
- * files/directories which have not been touched since ... a long time
- */
-abstract class HttpCachingBridgeAbstract extends BridgeAbstract {
-
-    /**
-     * Maintain locally cached versions of pages to download, to avoid multiple downloads.
-     * @param url url to cache
-     * @return content of the file as string
-     */
-    public function get_cached($url){
-        // TODO build this from the variable given to Cache
-        $cacheDir = __DIR__ . '/../cache/pages/';
-        $filepath = $this->buildCacheFilePath($url, $cacheDir);
-
-        if(file_exists($filepath)){
-            $this->debugMessage('loading cached file from ' . $filepath . ' for page at url ' . $url);
-            // TODO touch file and its parent, and try to do neighbour deletion
-            $this->refresh_in_cache($cacheDir, $filepath);
-            $content = file_get_contents($filepath);
-        } else {
-            $this->debugMessage('we have no local copy of ' . $url . ' Downloading to ' . $filepath);
-            $dir = substr($filepath, 0, strrpos($filepath, '/'));
-
-            if(!is_dir($dir)){
-                $this->debugMessage('creating directories for ' . $dir);
-                mkdir($dir, 0777, true);
-            }
-
-            $content = $this->getContents($url);
-            if($content !== false){
-                file_put_contents($filepath, $content);
-            }
-        }
-
-        return str_get_html($content);
-    }
-
-     public function get_cached_time($url){
-        // TODO build this from the variable given to Cache
-        $cacheDir = __DIR__ . '/../cache/pages/';
-        $filepath = $this->buildCacheFilePath($url, $cacheDir);
-
-        if(!file_exists($filepath)){
-            $this->get_cached($url);
-        }
-
-        return filectime($filepath);
-    }
-
-    private function refresh_in_cache($cacheDir, $filepath){
-        $currentPath = $filepath;
-        while(!$cacheDir == $currentPath){
-            touch($currentPath);
-            $currentPath = dirname($currentPath);
-        }
-    }
-
-    private function buildCacheFilePath($url, $cacheDir){
-        $simplified_url = str_replace(
-            ['http://', 'https://', '?', '&', '='],
-            ['', '', '/', '/', '/'],
-            $url);
-
-        if(substr($cacheDir, -1) !== '/'){
-            $cacheDir .= '/';
-        }
-
-        $filepath = $cacheDir . $simplified_url;
-
-        if(substr($filepath, -1) === '/'){
-            $filepath .= 'index.html';
-        }
-
-        return $filepath;
-    }
-
-    public function remove_from_cache($url){
-        // TODO build this from the variable given to Cache
-        $cacheDir = __DIR__ . '/../cache/pages/';
-        $filepath = $this->buildCacheFilePath($url, $cacheDir);
-        $this->debugMessage('removing from cache \'' . $filepath . '\'');
-        unlink($filepath);
-    }
-}
-
-abstract class FeedExpander extends HttpCachingBridgeAbstract {
-
-  private $name;
-  private $uri;
-  private $description;
-
-    public function collectExpandableDatas($url){
-        if(empty($url)){
-            $this->returnServerError('There is no $url for this RSS expander');
-        }
-
-        $this->debugMessage('Loading from ' . $url);
-
-        /* Notice we do not use cache here on purpose:
-         * we want a fresh view of the RSS stream each time
-         */
-        $content = $this->getContents($url) 
-            or $this->returnServerError('Could not request ' . $url);
-        $rssContent = simplexml_load_string($content);
-
-        $this->debugMessage('Detecting feed format/version');
-        if(isset($rssContent->channel[0])){
-            $this->debugMessage('Detected RSS format');
-            if(isset($rssContent->item[0])){
-                $this->debugMessage('Detected RSS 1.0 format');
-                $this->collect_RSS_1_0_data($rssContent);
-            } else {
-                $this->debugMessage('Detected RSS 0.9x or 2.0 format');
-                $this->collect_RSS_2_0_data($rssContent);
-            }
-        } elseif(isset($rssContent->entry[0])){
-            $this->debugMessage('Detected ATOM format');
-            $this->collect_ATOM_data($rssContent);
-        } else {
-            $this->debugMessage('Unknown feed format/version');
-            $this->returnServerError('The feed format is unknown!');
-        }
-    }
-
-    protected function collect_RSS_1_0_data($rssContent){
-        $this->load_RSS_2_0_feed_data($rssContent->channel[0]);
-        foreach($rssContent->item as $item){
-            $this->debugMessage('parsing item ' . var_export($item, true));
-            $this->items[] = $this->parseItem($item);
-        }
-    }
-
-    protected function collect_RSS_2_0_data($rssContent){
-        $rssContent = $rssContent->channel[0];
-        $this->debugMessage('RSS content is ===========\n' . var_export($rssContent, true) . '===========');
-        $this->load_RSS_2_0_feed_data($rssContent);
-        foreach($rssContent->item as $item){
-            $this->debugMessage('parsing item ' . var_export($item, true));
-            $this->items[] = $this->parseItem($item);
-        }
-    }
-
-    protected function collect_ATOM_data($content){
-        $this->load_ATOM_feed_data($content);
-        foreach($content->entry as $item){
-            $this->debugMessage('parsing item ' . var_export($item, true));
-            $this->items[] = $this->parseItem($item);
-        }
-    }
-
-    protected function RSS_2_0_time_to_timestamp($item){
-        return DateTime::createFromFormat('D, d M Y H:i:s e', $item->pubDate)->getTimestamp();
-    }
-
-    // TODO set title, link, description, language, and so on
-    protected function load_RSS_2_0_feed_data($rssContent){
-        $this->name = trim($rssContent->title);
-        $this->uri = trim($rssContent->link);
-        $this->description = trim($rssContent->description);
-    }
-
-    protected function load_ATOM_feed_data($content){
-        $this->name = $content->title;
-
-        // Find best link (only one, or first of 'alternate')
-        if(!isset($content->link)){
-            $this->uri = '';
-        } elseif (count($content->link) === 1){
-            $this->uri = $content->link[0]['href'];
-        } else {
-            $this->uri = '';
-            foreach($content->link as $link){
-                if(strtolower($link['rel']) === 'alternate'){
-                    $this->uri = $link['href'];
-                    break;
-                }
-            }
-        }
-
-        if(isset($content->subtitle))
-            $this->description = $content->subtitle;
-    }
-
-    protected function parseATOMItem($feedItem){
-        $item = array();
-        if(isset($feedItem->id)) $item['uri'] = $feedItem->id;
-        if(isset($feedItem->title)) $item['title'] = $feedItem->title;
-        if(isset($feedItem->updated)) $item['timestamp'] = strtotime($feedItem->updated);
-        if(isset($feedItem->author)) $item['author'] = $feedItem->author->name;
-        if(isset($feedItem->content)) $item['content'] = $feedItem->content;
-        return $item;
-    }
-
-    protected function parseRSS_0_9_1_Item($feedItem){
-        $item = array();
-        if(isset($feedItem->link)) $item['uri'] = $feedItem->link;
-        if(isset($feedItem->title)) $item['title'] = $feedItem->title;
-        // rss 0.91 doesn't support timestamps
-        // rss 0.91 doesn't support authors
-        if(isset($feedItem->description)) $item['content'] = $feedItem->description;
-        return $item;
-    }
-
-    protected function parseRSS_1_0_Item($feedItem){
-        // 1.0 adds optional elements around the 0.91 standard
-        $item = $this->parseRSS_0_9_1_Item($feedItem);
-
-        $namespaces = $feedItem->getNamespaces(true);
-        if(isset($namespaces['dc'])){
-            $dc = $feedItem->children($namespaces['dc']);
-            if(isset($dc->date)) $item['timestamp'] = strtotime($dc->date);
-            if(isset($dc->creator)) $item['author'] = $dc->creator;
-        }
-
-        return $item;
-    }
-
-    protected function parseRSS_2_0_Item($feedItem){
-        // Primary data is compatible to 0.91 with some additional data
-        $item = $this->parseRSS_0_9_1_Item($feedItem);
-
-        $namespaces = $feedItem->getNamespaces(true);
-        if(isset($namespaces['dc'])) $dc = $feedItem->children($namespaces['dc']);
-
-        if(isset($feedItem->pubDate)){
-            $item['timestamp'] = strtotime($feedItem->pubDate);
-        } elseif(isset($dc->date)){
-            $item['timestamp'] = strtotime($dc->date);
-        }
-        if(isset($feedItem->author)){
-            $item['author'] = $feedItem->author;
-        } elseif(isset($dc->creator)){
-            $item['author'] = $dc->creator;
-        }
-        return $item;
-    }
-
-    /**
-     * Method should return, from a source RSS item given by lastRSS, one of our Items objects
-     * @param $item the input rss item
-     * @return a RSS-Bridge Item, with (hopefully) the whole content)
-     */
-    abstract protected function parseItem($item);
-
-    public function getURI(){
-      return $this->uri;
-    }
-
-    public function getName(){
-      return $this->name;
-    }
-
-    public function getDescription(){
-        return $this->description;
-    }
-}
diff --git a/lib/BridgeAbstract.php b/lib/BridgeAbstract.php
new file mode 100644
index 00000000..f58e0566
--- /dev/null
+++ b/lib/BridgeAbstract.php
@@ -0,0 +1,389 @@
+<?php
+require_once(__DIR__ . '/BridgeInterface.php');
+abstract class BridgeAbstract implements BridgeInterface {
+
+    const NAME = 'Unnamed bridge';
+    const URI = '';
+    const DESCRIPTION = 'No description provided';
+    const MAINTAINER = 'No maintainer';
+    const PARAMETERS = array();
+
+    public $useProxy = true;
+
+    protected $cache;
+    protected $items = array();
+    protected $inputs = array();
+    protected $queriedContext = '';
+
+    protected function returnError($message, $code){
+        throw new \HttpException($message, $code);
+    }
+
+    protected function returnClientError($message){
+        $this->returnError($message, 400);
+    }
+
+    protected function returnServerError($message){
+        $this->returnError($message, 500);
+    }
+
+    /**
+    * Return items stored in the bridge
+    * @return mixed
+    */
+    public function getItems(){
+        return $this->items;
+    }
+
+    protected function validateTextValue($value, $pattern = null){
+        if(!is_null($pattern)){
+            $filteredValue = filter_var($value, FILTER_VALIDATE_REGEXP,
+                array('options' => array(
+                    'regexp' => '/^' . $pattern . '$/'
+                ))
+            );
+        } else {
+            $filteredValue = filter_var($value);
+        }
+
+        if($filteredValue === false)
+            return null;
+
+        return $filteredValue;
+    }
+
+    protected function validateNumberValue($value){
+        $filteredValue = filter_var($value, FILTER_VALIDATE_INT);
+
+        if($filteredValue === false && !empty($value))
+            return null;
+
+        return $filteredValue;
+    }
+
+    protected function validateCheckboxValue($value){
+        $filteredValue = filter_var($value, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
+
+        if(is_null($filteredValue))
+            return null;
+
+        return $filteredValue;
+    }
+
+    protected function validateListValue($value, $expectedValues){
+        $filteredValue = filter_var($value);
+
+        if($filteredValue === false)
+            return null;
+
+        if(!in_array($filteredValue, $expectedValues)){ // Check sub-values?
+            foreach($expectedValues as $subName => $subValue){
+                if(is_array($subValue) && in_array($filteredValue, $subValue))
+                    return $filteredValue;
+            }
+            return null;
+        }
+
+        return $filteredValue;
+    }
+
+    protected function validateData(&$data){
+        if(!is_array($data))
+            return false;
+
+        foreach($data as $name=>$value){
+            $registered = false;
+            foreach(static::PARAMETERS as $context=>$set){
+                if(array_key_exists($name,$set)){
+                    $registered = true;
+                    if(!isset($set[$name]['type'])){
+                        $set[$name]['type']='text';
+                    }
+
+                    switch($set[$name]['type']){
+                    case 'number':
+                        $data[$name] = $this->validateNumberValue($value);
+                        break;
+                    case 'checkbox':
+                        $data[$name] = $this->validateCheckboxValue($value);
+                        break;
+                    case 'list':
+                        $data[$name] = $this->validateListValue($value, $set[$name]['values']);
+                        break;
+                    default:
+                    case 'text':
+                        if(isset($set[$name]['pattern'])){
+                            $data[$name] = $this->validateTextValue($value, $set[$name]['pattern']);
+                        } else {
+                            $data[$name] = $this->validateTextValue($value);
+                        }
+                        break;
+                    }
+
+                    if(is_null($data[$name])){
+                        echo 'Parameter \'' . $name . '\' is invalid!' . PHP_EOL;
+                        return false;
+                    }
+                }
+            }
+
+            if(!$registered)
+                return false;
+        }
+
+        return true;
+    }
+
+    protected function setInputs(array $inputs, $queriedContext){
+        // Import and assign all inputs to their context
+        foreach($inputs as $name => $value){
+            foreach(static::PARAMETERS as $context => $set){
+                if(array_key_exists($name, static::PARAMETERS[$context])){
+                    $this->inputs[$context][$name]['value'] = $value;
+                }
+            }
+        }
+
+        // Apply default values to missing data
+        $contexts = array($queriedContext);
+        if(array_key_exists('global', static::PARAMETERS)){
+            $contexts[] = 'global';
+        }
+
+        foreach($contexts as $context){
+            foreach(static::PARAMETERS[$context] as $name => $properties){
+                if(isset($this->inputs[$context][$name]['value'])){
+                    continue;
+                }
+
+                $type = isset($properties['type']) ? $properties['type'] : 'text';
+
+                switch($type){
+                case 'checkbox':
+                    if(!isset($properties['defaultValue'])){
+                        $this->inputs[$context][$name]['value'] = false;
+                    } else {
+                        $this->inputs[$context][$name]['value'] = $properties['defaultValue'];
+                    }
+                    break;
+                case 'list':
+                    if(!isset($properties['defaultValue'])){
+                        $firstItem = reset($properties['values']);
+                        if(is_array($firstItem)){
+                            $firstItem = reset($firstItem);
+                        }
+                        $this->inputs[$context][$name]['value'] = $firstItem;
+                    } else {
+                        $this->inputs[$context][$name]['value'] = $properties['defaultValue'];
+                    }
+                    break;
+                default:
+                    if(isset($properties['defaultValue'])){
+                        $this->inputs[$context][$name]['value'] = $properties['defaultValue'];
+                    }
+                    break;
+                }
+            }
+        }
+
+        // Copy global parameter values to the guessed context
+        if(array_key_exists('global', static::PARAMETERS)){
+            foreach(static::PARAMETERS['global'] as $name => $properties){
+                if(isset($inputs[$name])){
+                    $value = $inputs[$name];
+                } elseif (isset($properties['value'])){
+                    $value = $properties['value'];
+                } else {
+                    continue;
+                }
+                $this->inputs[$queriedContext][$name]['value'] = $value;
+            }
+        }
+
+        // Only keep guessed context parameters values
+        if(isset($this->inputs[$queriedContext])){
+            $this->inputs = array($queriedContext => $this->inputs[$queriedContext]);
+        } else {
+            $this->inputs = array();
+        }
+    }
+
+    protected function getQueriedContext(array $inputs){
+        $queriedContexts=array();
+        foreach(static::PARAMETERS as $context=>$set){
+            $queriedContexts[$context]=null;
+            foreach($set as $id=>$properties){
+                if(isset($inputs[$id]) && !empty($inputs[$id])){
+                    $queriedContexts[$context]=true;
+                }elseif(isset($properties['required']) &&
+                    $properties['required']===true){
+                    $queriedContexts[$context]=false;
+                    break;
+                }
+            }
+        }
+
+        if(array_key_exists('global',static::PARAMETERS) &&
+            $queriedContexts['global']===false){
+            return null;
+        }
+        unset($queriedContexts['global']);
+
+        switch(array_sum($queriedContexts)){
+        case 0:
+            foreach($queriedContexts as $context=>$queried){
+                if (is_null($queried)){
+                    return $context;
+                }
+            }
+            return null;
+        case 1: return array_search(true,$queriedContexts);
+        default: return false;
+        }
+    }
+
+    /**
+    * Defined datas with parameters depending choose bridge
+    * Note : you can define a cache with "setCache"
+    * @param array array with expected bridge paramters
+    */
+    public function setDatas(array $inputs){
+        if(!is_null($this->cache)){
+            $this->cache->prepare($inputs);
+            $time = $this->cache->getTime();
+            if($time !== false && (time() - $this->getCacheDuration() < $time)){
+                $this->items = $this->cache->loadData();
+                return;
+            }
+        }
+
+        if(empty(static::PARAMETERS)){
+            if(!empty($inputs)){
+                $this->returnClientError('Invalid parameters value(s)');
+            }
+
+            $this->collectData();
+            if(!is_null($this->cache)){
+                $this->cache->saveData($this->getItems());
+            }
+            return;
+        }
+
+        if(!$this->validateData($inputs)){
+            $this->returnClientError('Invalid parameters value(s)');
+        }
+
+        // Guess the paramter context from input data
+        $this->queriedContext = $this->getQueriedContext($inputs);
+        if(is_null($this->queriedContext)){
+            $this->returnClientError('Required parameter(s) missing');
+        } elseif($this->queriedContext === false){
+            $this->returnClientError('Mixed context parameters');
+        }
+
+        $this->setInputs($inputs, $this->queriedContext);
+
+        $this->collectData();
+
+        if(!is_null($this->cache)){
+            $this->cache->saveData($this->getItems());
+        }
+    }
+
+    function getInput($input){
+        if(!isset($this->inputs[$this->queriedContext][$input]['value'])){
+            return null;
+        }
+        return $this->inputs[$this->queriedContext][$input]['value'];
+    }
+
+    public function getName(){
+        return static::NAME;
+    }
+
+    public function getURI(){
+        return static::URI;
+    }
+
+    public function getCacheDuration(){
+        return 3600;
+    }
+
+    public function setCache(\CacheAbstract $cache){
+        $this->cache = $cache;
+    }
+
+    public function debugMessage($text){
+        if(!file_exists('DEBUG')) {
+            return;
+        }
+
+        $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 3);
+        $calling = $backtrace[2];
+        $message = $calling['file'] . ':'
+        . $calling['line'] . ' class '
+        . get_class($this) . '->'
+        . $calling['function'] . ' - '
+        . $text;
+
+        error_log($message);
+    }
+
+    protected function getContents($url
+    , $use_include_path = false
+    , $context = null
+    , $offset = 0
+    , $maxlen = null){
+        $contextOptions = array(
+            'http' => array(
+                'user_agent' => ini_get('user_agent')
+            ),
+        );
+
+        if(defined('PROXY_URL') && $this->useProxy){
+            $contextOptions['http']['proxy'] = PROXY_URL;
+            $contextOptions['http']['request_fulluri'] = true;
+
+            if(is_null($context)){
+                $context = stream_context_create($contextOptions);
+            } else {
+                $prevContext=$context;
+                if(!stream_context_set_option($context, $contextOptions)){
+                    $context = $prevContext;
+                }
+            }
+        }
+
+        if(is_null($maxlen)){
+            $content = @file_get_contents($url, $use_include_path, $context, $offset);
+        } else {
+            $content = @file_get_contents($url, $use_include_path, $context, $offset, $maxlen);
+        }
+
+        if($content === false)
+            $this->debugMessage('Cant\'t download ' . $url);
+
+        return $content;
+    }
+
+    protected function getSimpleHTMLDOM($url
+    , $use_include_path = false
+    , $context = null
+    , $offset = 0
+    , $maxLen = null
+    , $lowercase = true
+    , $forceTagsClosed = true
+    , $target_charset = DEFAULT_TARGET_CHARSET
+    , $stripRN = true
+    , $defaultBRText = DEFAULT_BR_TEXT
+    , $defaultSpanText = DEFAULT_SPAN_TEXT){
+      $content = $this->getContents($url, $use_include_path, $context, $offset, $maxLen);
+      return str_get_html($content
+      , $lowercase
+      , $forceTagsClosed
+      , $target_charset
+      , $stripRN
+      , $defaultBRText
+      , $defaultSpanText);
+    }
+}
diff --git a/lib/BridgeInterface.php b/lib/BridgeInterface.php
new file mode 100644
index 00000000..5054d102
--- /dev/null
+++ b/lib/BridgeInterface.php
@@ -0,0 +1,7 @@
+<?php
+interface BridgeInterface {
+    public function collectData();
+    public function getCacheDuration();
+    public function getName();
+    public function getURI();
+}
diff --git a/lib/Cache.php b/lib/Cache.php
index a165148d..572b96dc 100644
--- a/lib/Cache.php
+++ b/lib/Cache.php
@@ -1,25 +1,5 @@
 <?php
-/**
-* All cache logic
-* Note : adapter are store in other place
-*/
-
-interface CacheInterface{
-    public function loadData();
-    public function saveData($datas);
-    public function getTime();
-}
-
-abstract class CacheAbstract implements CacheInterface{
-    protected $param;
-
-    public function prepare(array $param){
-        $this->param = $param;
-
-        return $this;
-    }
-}
-
+require_once(__DIR__ . '/CacheInterface.php');
 class Cache{
 
     static protected $dirCache;
diff --git a/lib/CacheAbstract.php b/lib/CacheAbstract.php
new file mode 100644
index 00000000..98608b25
--- /dev/null
+++ b/lib/CacheAbstract.php
@@ -0,0 +1,11 @@
+<?php
+require_once(__DIR__ . '/CacheInterface.php');
+abstract class CacheAbstract implements CacheInterface{
+    protected $param;
+
+    public function prepare(array $param){
+        $this->param = $param;
+
+        return $this;
+    }
+}
diff --git a/lib/CacheInterface.php b/lib/CacheInterface.php
new file mode 100644
index 00000000..89d78ecc
--- /dev/null
+++ b/lib/CacheInterface.php
@@ -0,0 +1,6 @@
+<?php
+interface CacheInterface{
+    public function loadData();
+    public function saveData($datas);
+    public function getTime();
+}
diff --git a/lib/FeedExpander.php b/lib/FeedExpander.php
new file mode 100644
index 00000000..f164799e
--- /dev/null
+++ b/lib/FeedExpander.php
@@ -0,0 +1,173 @@
+<?php
+require_once(__DIR__ . '/BridgeInterface.php');
+abstract class FeedExpander extends HttpCachingBridgeAbstract {
+
+  private $name;
+  private $uri;
+  private $description;
+
+    public function collectExpandableDatas($url){
+        if(empty($url)){
+            $this->returnServerError('There is no $url for this RSS expander');
+        }
+
+        $this->debugMessage('Loading from ' . $url);
+
+        /* Notice we do not use cache here on purpose:
+         * we want a fresh view of the RSS stream each time
+         */
+        $content = $this->getContents($url) 
+            or $this->returnServerError('Could not request ' . $url);
+        $rssContent = simplexml_load_string($content);
+
+        $this->debugMessage('Detecting feed format/version');
+        if(isset($rssContent->channel[0])){
+            $this->debugMessage('Detected RSS format');
+            if(isset($rssContent->item[0])){
+                $this->debugMessage('Detected RSS 1.0 format');
+                $this->collect_RSS_1_0_data($rssContent);
+            } else {
+                $this->debugMessage('Detected RSS 0.9x or 2.0 format');
+                $this->collect_RSS_2_0_data($rssContent);
+            }
+        } elseif(isset($rssContent->entry[0])){
+            $this->debugMessage('Detected ATOM format');
+            $this->collect_ATOM_data($rssContent);
+        } else {
+            $this->debugMessage('Unknown feed format/version');
+            $this->returnServerError('The feed format is unknown!');
+        }
+    }
+
+    protected function collect_RSS_1_0_data($rssContent){
+        $this->load_RSS_2_0_feed_data($rssContent->channel[0]);
+        foreach($rssContent->item as $item){
+            $this->debugMessage('parsing item ' . var_export($item, true));
+            $this->items[] = $this->parseItem($item);
+        }
+    }
+
+    protected function collect_RSS_2_0_data($rssContent){
+        $rssContent = $rssContent->channel[0];
+        $this->debugMessage('RSS content is ===========\n' . var_export($rssContent, true) . '===========');
+        $this->load_RSS_2_0_feed_data($rssContent);
+        foreach($rssContent->item as $item){
+            $this->debugMessage('parsing item ' . var_export($item, true));
+            $this->items[] = $this->parseItem($item);
+        }
+    }
+
+    protected function collect_ATOM_data($content){
+        $this->load_ATOM_feed_data($content);
+        foreach($content->entry as $item){
+            $this->debugMessage('parsing item ' . var_export($item, true));
+            $this->items[] = $this->parseItem($item);
+        }
+    }
+
+    protected function RSS_2_0_time_to_timestamp($item){
+        return DateTime::createFromFormat('D, d M Y H:i:s e', $item->pubDate)->getTimestamp();
+    }
+
+    // TODO set title, link, description, language, and so on
+    protected function load_RSS_2_0_feed_data($rssContent){
+        $this->name = trim($rssContent->title);
+        $this->uri = trim($rssContent->link);
+        $this->description = trim($rssContent->description);
+    }
+
+    protected function load_ATOM_feed_data($content){
+        $this->name = $content->title;
+
+        // Find best link (only one, or first of 'alternate')
+        if(!isset($content->link)){
+            $this->uri = '';
+        } elseif (count($content->link) === 1){
+            $this->uri = $content->link[0]['href'];
+        } else {
+            $this->uri = '';
+            foreach($content->link as $link){
+                if(strtolower($link['rel']) === 'alternate'){
+                    $this->uri = $link['href'];
+                    break;
+                }
+            }
+        }
+
+        if(isset($content->subtitle))
+            $this->description = $content->subtitle;
+    }
+
+    protected function parseATOMItem($feedItem){
+        $item = array();
+        if(isset($feedItem->id)) $item['uri'] = $feedItem->id;
+        if(isset($feedItem->title)) $item['title'] = $feedItem->title;
+        if(isset($feedItem->updated)) $item['timestamp'] = strtotime($feedItem->updated);
+        if(isset($feedItem->author)) $item['author'] = $feedItem->author->name;
+        if(isset($feedItem->content)) $item['content'] = $feedItem->content;
+        return $item;
+    }
+
+    protected function parseRSS_0_9_1_Item($feedItem){
+        $item = array();
+        if(isset($feedItem->link)) $item['uri'] = $feedItem->link;
+        if(isset($feedItem->title)) $item['title'] = $feedItem->title;
+        // rss 0.91 doesn't support timestamps
+        // rss 0.91 doesn't support authors
+        if(isset($feedItem->description)) $item['content'] = $feedItem->description;
+        return $item;
+    }
+
+    protected function parseRSS_1_0_Item($feedItem){
+        // 1.0 adds optional elements around the 0.91 standard
+        $item = $this->parseRSS_0_9_1_Item($feedItem);
+
+        $namespaces = $feedItem->getNamespaces(true);
+        if(isset($namespaces['dc'])){
+            $dc = $feedItem->children($namespaces['dc']);
+            if(isset($dc->date)) $item['timestamp'] = strtotime($dc->date);
+            if(isset($dc->creator)) $item['author'] = $dc->creator;
+        }
+
+        return $item;
+    }
+
+    protected function parseRSS_2_0_Item($feedItem){
+        // Primary data is compatible to 0.91 with some additional data
+        $item = $this->parseRSS_0_9_1_Item($feedItem);
+
+        $namespaces = $feedItem->getNamespaces(true);
+        if(isset($namespaces['dc'])) $dc = $feedItem->children($namespaces['dc']);
+
+        if(isset($feedItem->pubDate)){
+            $item['timestamp'] = strtotime($feedItem->pubDate);
+        } elseif(isset($dc->date)){
+            $item['timestamp'] = strtotime($dc->date);
+        }
+        if(isset($feedItem->author)){
+            $item['author'] = $feedItem->author;
+        } elseif(isset($dc->creator)){
+            $item['author'] = $dc->creator;
+        }
+        return $item;
+    }
+
+    /**
+     * Method should return, from a source RSS item given by lastRSS, one of our Items objects
+     * @param $item the input rss item
+     * @return a RSS-Bridge Item, with (hopefully) the whole content)
+     */
+    abstract protected function parseItem($item);
+
+    public function getURI(){
+      return $this->uri;
+    }
+
+    public function getName(){
+      return $this->name;
+    }
+
+    public function getDescription(){
+        return $this->description;
+    }
+}
diff --git a/lib/Format.php b/lib/Format.php
index 8053d36d..618c0a30 100644
--- a/lib/Format.php
+++ b/lib/Format.php
@@ -1,121 +1,5 @@
 <?php
-/**
-* All format logic
-* Note : adapter are store in other place
-*/
-
-interface FormatInterface{
-    public function stringify();
-    public function display();
-    public function setItems(array $bridges);
-}
-
-abstract class FormatAbstract implements FormatInterface{
-    const DEFAULT_CHARSET = 'UTF-8';
-
-    protected 
-        $contentType,
-        $charset,
-        $items,
-        $extraInfos
-    ;
-
-    public function setCharset($charset){
-        $this->charset = $charset;
-
-        return $this;
-    }
-
-    public function getCharset(){
-        $charset = $this->charset;
-
-        return is_null($charset) ? self::DEFAULT_CHARSET : $charset;
-    }
-
-    protected function setContentType($contentType){
-        $this->contentType = $contentType;
-
-        return $this;
-    }
-
-    protected function callContentType(){
-        header('Content-Type: ' . $this->contentType);
-    }
-
-    public function display(){
-        echo $this->stringify();
-
-        return $this;
-    }
-
-    public function setItems(array $items){
-        $this->items = array_map(array($this, 'array_trim'), $items);
-
-        return $this;
-    }
-
-    public function getItems(){
-        if(!is_array($this->items))
-            throw new \LogicException('Feed the ' . get_class($this) . ' with "setItems" method before !');
-
-        return $this->items;
-    }
-
-    /**
-    * Define common informations can be required by formats and set default value for unknow values
-    * @param array $extraInfos array with know informations (there isn't merge !!!)
-    * @return this
-    */
-    public function setExtraInfos(array $extraInfos = array()){    
-        foreach(array('name', 'uri') as $infoName){
-            if( !isset($extraInfos[$infoName]) ){
-                $extraInfos[$infoName] = '';
-            }
-        }
-
-        $this->extraInfos = $extraInfos;
-
-        return $this;
-    }
-
-    /**
-    * Return extra infos
-    * @return array See "setExtraInfos" detail method to know what extra are disponibles
-    */
-    public function getExtraInfos(){
-        if( is_null($this->extraInfos) ){ // No extra info ?
-            $this->setExtraInfos(); // Define with default value
-        }
-
-        return $this->extraInfos;
-    }
-    
-    /**
-     * Sanitized html while leaving it functionnal.
-     * The aim is to keep html as-is (with clickable hyperlinks)
-     * while reducing annoying and potentially dangerous things.
-     * Yes, I know sanitizing HTML 100% is an impossible task.
-     * Maybe we'll switch to http://htmlpurifier.org/
-     * or http://www.bioinformatics.org/phplabware/internal_utilities/htmLawed/index.php
-     */
-    protected function sanitizeHtml($html)
-    {
-        $html = str_replace('<script','<&zwnj;script',$html); // Disable scripts, but leave them visible.
-        $html = str_replace('<iframe','<&zwnj;iframe',$html);
-        $html = str_replace('<link','<&zwnj;link',$html);
-        // We leave alone object and embed so that videos can play in RSS readers.
-        return $html;
-    }
-
-    protected function array_trim($elements){
-        foreach($elements as $key => $value){
-            if(is_string($value))
-                $elements[$key] = trim($value);
-        }
-        return $elements;
-    }
-}
-
+require_once(__DIR__ . '/FormatInterface.php');
 class Format{
 
     static protected $dirFormat;
diff --git a/lib/FormatAbstract.php b/lib/FormatAbstract.php
new file mode 100644
index 00000000..e4a911c1
--- /dev/null
+++ b/lib/FormatAbstract.php
@@ -0,0 +1,107 @@
+<?php
+require_once(__DIR__ . '/FormatInterface.php');
+abstract class FormatAbstract implements FormatInterface{
+    const DEFAULT_CHARSET = 'UTF-8';
+
+    protected 
+        $contentType,
+        $charset,
+        $items,
+        $extraInfos
+    ;
+
+    public function setCharset($charset){
+        $this->charset = $charset;
+
+        return $this;
+    }
+
+    public function getCharset(){
+        $charset = $this->charset;
+
+        return is_null($charset) ? self::DEFAULT_CHARSET : $charset;
+    }
+
+    protected function setContentType($contentType){
+        $this->contentType = $contentType;
+
+        return $this;
+    }
+
+    protected function callContentType(){
+        header('Content-Type: ' . $this->contentType);
+    }
+
+    public function display(){
+        echo $this->stringify();
+
+        return $this;
+    }
+
+    public function setItems(array $items){
+        $this->items = array_map(array($this, 'array_trim'), $items);
+
+        return $this;
+    }
+
+    public function getItems(){
+        if(!is_array($this->items))
+            throw new \LogicException('Feed the ' . get_class($this) . ' with "setItems" method before !');
+
+        return $this->items;
+    }
+
+    /**
+    * Define common informations can be required by formats and set default value for unknow values
+    * @param array $extraInfos array with know informations (there isn't merge !!!)
+    * @return this
+    */
+    public function setExtraInfos(array $extraInfos = array()){    
+        foreach(array('name', 'uri') as $infoName){
+            if( !isset($extraInfos[$infoName]) ){
+                $extraInfos[$infoName] = '';
+            }
+        }
+
+        $this->extraInfos = $extraInfos;
+
+        return $this;
+    }
+
+    /**
+    * Return extra infos
+    * @return array See "setExtraInfos" detail method to know what extra are disponibles
+    */
+    public function getExtraInfos(){
+        if( is_null($this->extraInfos) ){ // No extra info ?
+            $this->setExtraInfos(); // Define with default value
+        }
+
+        return $this->extraInfos;
+    }
+    
+    /**
+     * Sanitized html while leaving it functionnal.
+     * The aim is to keep html as-is (with clickable hyperlinks)
+     * while reducing annoying and potentially dangerous things.
+     * Yes, I know sanitizing HTML 100% is an impossible task.
+     * Maybe we'll switch to http://htmlpurifier.org/
+     * or http://www.bioinformatics.org/phplabware/internal_utilities/htmLawed/index.php
+     */
+    protected function sanitizeHtml($html)
+    {
+        $html = str_replace('<script','<&zwnj;script',$html); // Disable scripts, but leave them visible.
+        $html = str_replace('<iframe','<&zwnj;iframe',$html);
+        $html = str_replace('<link','<&zwnj;link',$html);
+        // We leave alone object and embed so that videos can play in RSS readers.
+        return $html;
+    }
+
+    protected function array_trim($elements){
+        foreach($elements as $key => $value){
+            if(is_string($value))
+                $elements[$key] = trim($value);
+        }
+        return $elements;
+    }
+}
diff --git a/lib/FormatInterface.php b/lib/FormatInterface.php
new file mode 100644
index 00000000..ea0cf233
--- /dev/null
+++ b/lib/FormatInterface.php
@@ -0,0 +1,6 @@
+<?php
+interface FormatInterface{
+    public function stringify();
+    public function display();
+    public function setItems(array $bridges);
+}
diff --git a/lib/HttpCachingBridgeAbstract.php b/lib/HttpCachingBridgeAbstract.php
new file mode 100644
index 00000000..15cddc5b
--- /dev/null
+++ b/lib/HttpCachingBridgeAbstract.php
@@ -0,0 +1,89 @@
+<?php
+require_once(__DIR__ . '/BridgeInterface.php');
+/**
+ * Extension of BridgeAbstract allowing caching of files downloaded over http.
+ * TODO allow file cache invalidation by touching files on access, and removing
+ * files/directories which have not been touched since ... a long time
+ */
+abstract class HttpCachingBridgeAbstract extends BridgeAbstract {
+
+    /**
+     * Maintain locally cached versions of pages to download, to avoid multiple downloads.
+     * @param url url to cache
+     * @return content of the file as string
+     */
+    public function get_cached($url){
+        // TODO build this from the variable given to Cache
+        $cacheDir = __DIR__ . '/../cache/pages/';
+        $filepath = $this->buildCacheFilePath($url, $cacheDir);
+
+        if(file_exists($filepath)){
+            $this->debugMessage('loading cached file from ' . $filepath . ' for page at url ' . $url);
+            // TODO touch file and its parent, and try to do neighbour deletion
+            $this->refresh_in_cache($cacheDir, $filepath);
+            $content = file_get_contents($filepath);
+        } else {
+            $this->debugMessage('we have no local copy of ' . $url . ' Downloading to ' . $filepath);
+            $dir = substr($filepath, 0, strrpos($filepath, '/'));
+
+            if(!is_dir($dir)){
+                $this->debugMessage('creating directories for ' . $dir);
+                mkdir($dir, 0777, true);
+            }
+
+            $content = $this->getContents($url);
+            if($content !== false){
+                file_put_contents($filepath, $content);
+            }
+        }
+
+        return str_get_html($content);
+    }
+
+     public function get_cached_time($url){
+        // TODO build this from the variable given to Cache
+        $cacheDir = __DIR__ . '/../cache/pages/';
+        $filepath = $this->buildCacheFilePath($url, $cacheDir);
+
+        if(!file_exists($filepath)){
+            $this->get_cached($url);
+        }
+
+        return filectime($filepath);
+    }
+
+    private function refresh_in_cache($cacheDir, $filepath){
+        $currentPath = $filepath;
+        while(!$cacheDir == $currentPath){
+            touch($currentPath);
+            $currentPath = dirname($currentPath);
+        }
+    }
+
+    private function buildCacheFilePath($url, $cacheDir){
+        $simplified_url = str_replace(
+            ['http://', 'https://', '?', '&', '='],
+            ['', '', '/', '/', '/'],
+            $url);
+
+        if(substr($cacheDir, -1) !== '/'){
+            $cacheDir .= '/';
+        }
+
+        $filepath = $cacheDir . $simplified_url;
+
+        if(substr($filepath, -1) === '/'){
+            $filepath .= 'index.html';
+        }
+
+        return $filepath;
+    }
+
+    public function remove_from_cache($url){
+        // TODO build this from the variable given to Cache
+        $cacheDir = __DIR__ . '/../cache/pages/';
+        $filepath = $this->buildCacheFilePath($url, $cacheDir);
+        $this->debugMessage('removing from cache \'' . $filepath . '\'');
+        unlink($filepath);
+    }
+}
diff --git a/lib/RssBridge.php b/lib/RssBridge.php
index 4b0aab52..6dd26631 100644
--- a/lib/RssBridge.php
+++ b/lib/RssBridge.php
@@ -9,8 +9,13 @@ define('PATH_VENDOR', '/../vendor');
 
 require __DIR__ . '/Exceptions.php';
 require __DIR__ . '/Format.php';
+require __DIR__ . '/FormatAbstract.php';
 require __DIR__ . '/Bridge.php';
+require __DIR__ . '/BridgeAbstract.php';
+require __DIR__ . '/HttpCachingBridgeAbstract.php';
+require __DIR__ . '/FeedExpander.php';
 require __DIR__ . '/Cache.php';
+require __DIR__ . '/CacheAbstract.php';
 require __DIR__ . '/HTMLUtils.php';
 
 $vendorLibSimpleHtmlDom = __DIR__ . PATH_VENDOR . '/simplehtmldom/simple_html_dom.php';