41 files changed, 885 insertions, 486 deletions
diff --git a/application/ApplicationUtils.php b/application/ApplicationUtils.php
index 911873a0..7fe3cb32 100644
--- a/application/ApplicationUtils.php
+++ b/application/ApplicationUtils.php
@@ -1,4 +1,9 @@
 <?php
+namespace Shaarli;
+use Exception;
+use Shaarli\Config\ConfigManager;
 /**
 * Shaarli (application) utilities
 */
@@ -24,7 +29,7 @@ class ApplicationUtils
     *
     * @return mixed the version code from the repository if available, else 'false'
     */
-    public static function getLatestGitVersionCode($url, $timeout=2)
+    public static function getLatestGitVersionCode($url, $timeout = 2)
    {
        list($headers, $data) = get_http_response($url, $timeout);
@@ -51,7 +56,7 @@ class ApplicationUtils
                return false;
            }
        } else {
-            if (! is_file($remote)) {
+            if (!is_file($remote)) {
                return false;
            }
            $data = file_get_contents($remote);
@@ -86,17 +91,18 @@ class ApplicationUtils
     *
     * @return mixed the new version code if available and greater, else 'false'
     */
-    public static function checkUpdate($currentVersion,
+    public static function checkUpdate(
-                                       $updateFile,
+        $currentVersion,
-                                       $checkInterval,
+        $updateFile,
-                                       $enableCheck,
+        $checkInterval,
-                                       $isLoggedIn,
+        $enableCheck,
-                                       $branch='stable')
+        $isLoggedIn,
-    {
+        $branch = 'stable'
+    ) {
        // Do not check versions for visitors
        // Do not check if the user doesn't want to
        // Do not check with dev version
-        if (! $isLoggedIn || empty($enableCheck) || $currentVersion === 'dev') {
+        if (!$isLoggedIn || empty($enableCheck) || $currentVersion === 'dev') {
            return false;
        }
@@ -110,7 +116,7 @@ class ApplicationUtils
            return false;
        }
-        if (! in_array($branch, self::$GIT_BRANCHES)) {
+        if (!in_array($branch, self::$GIT_BRANCHES)) {
            throw new Exception(
                'Invalid branch selected for updates: "' . $branch . '"'
            );
@@ -122,7 +128,7 @@ class ApplicationUtils
            self::$GIT_URL . '/' . $branch . '/' . self::$VERSION_FILE
        );
-        if (! $latestVersion) {
+        if (!$latestVersion) {
            // Only update the file's modification date
            file_put_contents($updateFile, $currentVersion);
            return false;
@@ -151,9 +157,9 @@ class ApplicationUtils
        if (version_compare($curVersion, $minVersion) < 0) {
            $msg = t(
                'Your PHP version is obsolete!'
-                 . ' Shaarli requires at least PHP %s, and thus cannot run.'
+                . ' Shaarli requires at least PHP %s, and thus cannot run.'
-                 . ' Your PHP version has known security vulnerabilities and should be'
+                . ' Your PHP version has known security vulnerabilities and should be'
-                 . ' updated as soon as possible.'
+                . ' updated as soon as possible.'
            );
            throw new Exception(sprintf($msg, $minVersion));
        }
@@ -173,50 +179,50 @@ class ApplicationUtils
        // Check script and template directories are readable
        foreach (array(
-            'application',
+                     'application',
-            'inc',
+                     'inc',
-            'plugins',
+                     'plugins',
-            $rainTplDir,
+                     $rainTplDir,
-            $rainTplDir.'/'.$conf->get('resource.theme'),
+                     $rainTplDir . '/' . $conf->get('resource.theme'),
-        ) as $path) {
+                 ) as $path) {
-            if (! is_readable(realpath($path))) {
+            if (!is_readable(realpath($path))) {
-                $errors[] = '"'.$path.'" '. t('directory is not readable');
+                $errors[] = '"' . $path . '" ' . t('directory is not readable');
            }
        }
        // Check cache and data directories are readable and writable
        foreach (array(
-            $conf->get('resource.thumbnails_cache'),
+                     $conf->get('resource.thumbnails_cache'),
-            $conf->get('resource.data_dir'),
+                     $conf->get('resource.data_dir'),
-            $conf->get('resource.page_cache'),
+                     $conf->get('resource.page_cache'),
-            $conf->get('resource.raintpl_tmp'),
+                     $conf->get('resource.raintpl_tmp'),
-        ) as $path) {
+                 ) as $path) {
-            if (! is_readable(realpath($path))) {
+            if (!is_readable(realpath($path))) {
-                $errors[] = '"'.$path.'" '. t('directory is not readable');
+                $errors[] = '"' . $path . '" ' . t('directory is not readable');
            }
-            if (! is_writable(realpath($path))) {
+            if (!is_writable(realpath($path))) {
-                $errors[] = '"'.$path.'" '. t('directory is not writable');
+                $errors[] = '"' . $path . '" ' . t('directory is not writable');
            }
        }
        // Check configuration files are readable and writable
        foreach (array(
-            $conf->getConfigFileExt(),
+                     $conf->getConfigFileExt(),
-            $conf->get('resource.datastore'),
+                     $conf->get('resource.datastore'),
-            $conf->get('resource.ban_file'),
+                     $conf->get('resource.ban_file'),
-            $conf->get('resource.log'),
+                     $conf->get('resource.log'),
-            $conf->get('resource.update_check'),
+                     $conf->get('resource.update_check'),
-        ) as $path) {
+                 ) as $path) {
-            if (! is_file(realpath($path))) {
+            if (!is_file(realpath($path))) {
                # the file may not exist yet
                continue;
            }
-            if (! is_readable(realpath($path))) {
+            if (!is_readable(realpath($path))) {
-                $errors[] = '"'.$path.'" '. t('file is not readable');
+                $errors[] = '"' . $path . '" ' . t('file is not readable');
            }
-            if (! is_writable(realpath($path))) {
+            if (!is_writable(realpath($path))) {
-                $errors[] = '"'.$path.'" '. t('file is not writable');
+                $errors[] = '"' . $path . '" ' . t('file is not writable');
            }
        }
diff --git a/application/FileUtils.php b/application/FileUtils.php
index b89ea12b..30560bfc 100644
--- a/application/FileUtils.php
+++ b/application/FileUtils.php
@@ -1,6 +1,8 @@
 <?php
-require_once 'exceptions/IOException.php';
+namespace Shaarli;
+use Shaarli\Exceptions\IOException;
 /**
 * Class FileUtils
@@ -44,7 +46,7 @@ class FileUtils
        return file_put_contents(
            $file,
-            self::$phpPrefix.base64_encode(gzdeflate(serialize($content))).self::$phpSuffix
+            self::$phpPrefix . base64_encode(gzdeflate(serialize($content))) . self::$phpSuffix
        );
    }
@@ -62,7 +64,7 @@ class FileUtils
    {
        // Note that gzinflate is faster than gzuncompress.
        // See: http://www.php.net/manual/en/function.gzdeflate.php#96439
-        if (! is_readable($file)) {
+        if (!is_readable($file)) {
            return $default;
        }
diff --git a/application/History.php b/application/History.php
index 35ec016a..a5846652 100644
--- a/application/History.php
+++ b/application/History.php
@@ -1,4 +1,8 @@
 <?php
+namespace Shaarli;
+use DateTime;
+use Exception;
 /**
 * Class History
@@ -66,7 +70,7 @@ class History
     * History constructor.
     *
     * @param string $historyFilePath History file path.
-     * @param int    $retentionTime   History content rentention time in seconds.
+     * @param int    $retentionTime   History content retention time in seconds.
     *
     * @throws Exception if something goes wrong.
     */
@@ -166,11 +170,11 @@ class History
     */
    protected function check()
    {
-        if (! is_file($this->historyFilePath)) {
+        if (!is_file($this->historyFilePath)) {
            FileUtils::writeFlatDB($this->historyFilePath, []);
        }
-        if (! is_writable($this->historyFilePath)) {
+        if (!is_writable($this->historyFilePath)) {
            throw new Exception(t('History file isn\'t readable or writable'));
        }
    }
@@ -191,7 +195,7 @@ class History
     */
    protected function write()
    {
-        $comparaison = new DateTime('-'. $this->retentionTime . ' seconds');
+        $comparaison = new DateTime('-' . $this->retentionTime . ' seconds');
        foreach ($this->history as $key => $value) {
            if ($value['datetime'] < $comparaison) {
                unset($this->history[$key]);
diff --git a/application/Languages.php b/application/Languages.php
index 4fa32426..5cda802e 100644
--- a/application/Languages.php
+++ b/application/Languages.php
@@ -3,7 +3,6 @@
 namespace Shaarli;
 use Gettext\GettextTranslator;
-use Gettext\Merge;
 use Gettext\Translations;
 use Gettext\Translator;
 use Gettext\TranslatorInterface;
@@ -92,7 +91,7 @@ class Languages
    /**
     * Initialize the translator using php gettext extension (gettext dependency act as a wrapper).
     */
-    protected function initGettextTranslator ()
+    protected function initGettextTranslator()
    {
        $this->translator = new GettextTranslator();
        $this->translator->setLanguage($this->language);
@@ -125,7 +124,8 @@ class Languages
            $translations = $translations->addFromPoFile('inc/languages/'. $this->language .'/LC_MESSAGES/shaarli.po');
            $translations->setDomain('shaarli');
            $this->translator->loadTranslations($translations);
-        } catch (\InvalidArgumentException $e) {}
+        } catch (\InvalidArgumentException $e) {
+        }
        // Default extension translation from the current theme
        $theme = $this->conf->get('theme');
@@ -137,7 +137,8 @@ class Languages
                );
                $translations->setDomain($theme);
                $this->translator->loadTranslations($translations);
-            } catch (\InvalidArgumentException $e) {}
+            } catch (\InvalidArgumentException $e) {
+            }
        }
        // Extension translations (plugins, themes, etc.).
@@ -147,10 +148,13 @@ class Languages
            }
            try {
-                $extension = Translations::fromPoFile($translationPath . $this->language .'/LC_MESSAGES/'. $domain .'.po');
+                $extension = Translations::fromPoFile(
+                    $translationPath . $this->language .'/LC_MESSAGES/'. $domain .'.po'
+                );
                $extension->setDomain($domain);
                $this->translator->loadTranslations($extension);
-            } catch (\InvalidArgumentException $e) {}
+            } catch (\InvalidArgumentException $e) {
+            }
        }
    }
diff --git a/application/Router.php b/application/Router.php
index 4df0387c..05877acd 100644
--- a/application/Router.php
+++ b/application/Router.php
@@ -1,4 +1,5 @@
 <?php
+namespace Shaarli;
 /**
 * Class Router
@@ -7,6 +8,8 @@
 */
 class Router
 {
+    public static $AJAX_THUMB_UPDATE = 'ajax_thumb_update';
    public static $PAGE_LOGIN = 'login';
    public static $PAGE_PICWALL = 'picwall';
@@ -35,6 +38,8 @@ class Router
    public static $PAGE_DELETELINK = 'delete_link';
+    public static $PAGE_PINLINK = 'pin';
    public static $PAGE_EXPORT = 'export';
    public static $PAGE_IMPORT = 'import';
@@ -47,6 +52,8 @@ class Router
    public static $PAGE_SAVE_PLUGINSADMIN = 'save_pluginadmin';
+    public static $PAGE_THUMBS_UPDATE = 'thumbs_update';
    public static $GET_TOKEN = 'token';
    /**
@@ -69,60 +76,68 @@ class Router
            return self::$PAGE_LINKLIST;
        }
-        if (startsWith($query, 'do='. self::$PAGE_LOGIN) && $loggedIn === false) {
+        if (startsWith($query, 'do=' . self::$PAGE_LOGIN) && $loggedIn === false) {
            return self::$PAGE_LOGIN;
        }
-        if (startsWith($query, 'do='. self::$PAGE_PICWALL)) {
+        if (startsWith($query, 'do=' . self::$PAGE_PICWALL)) {
            return self::$PAGE_PICWALL;
        }
-        if (startsWith($query, 'do='. self::$PAGE_TAGCLOUD)) {
+        if (startsWith($query, 'do=' . self::$PAGE_TAGCLOUD)) {
            return self::$PAGE_TAGCLOUD;
        }
-        if (startsWith($query, 'do='. self::$PAGE_TAGLIST)) {
+        if (startsWith($query, 'do=' . self::$PAGE_TAGLIST)) {
            return self::$PAGE_TAGLIST;
        }
-        if (startsWith($query, 'do='. self::$PAGE_OPENSEARCH)) {
+        if (startsWith($query, 'do=' . self::$PAGE_OPENSEARCH)) {
            return self::$PAGE_OPENSEARCH;
        }
-        if (startsWith($query, 'do='. self::$PAGE_DAILY)) {
+        if (startsWith($query, 'do=' . self::$PAGE_DAILY)) {
            return self::$PAGE_DAILY;
        }
-        if (startsWith($query, 'do='. self::$PAGE_FEED_ATOM)) {
+        if (startsWith($query, 'do=' . self::$PAGE_FEED_ATOM)) {
            return self::$PAGE_FEED_ATOM;
        }
-        if (startsWith($query, 'do='. self::$PAGE_FEED_RSS)) {
+        if (startsWith($query, 'do=' . self::$PAGE_FEED_RSS)) {
            return self::$PAGE_FEED_RSS;
        }
+        if (startsWith($query, 'do=' . self::$PAGE_THUMBS_UPDATE)) {
+            return self::$PAGE_THUMBS_UPDATE;
+        }
+        if (startsWith($query, 'do=' . self::$AJAX_THUMB_UPDATE)) {
+            return self::$AJAX_THUMB_UPDATE;
+        }
        // At this point, only loggedin pages.
        if (!$loggedIn) {
            return self::$PAGE_LINKLIST;
        }
-        if (startsWith($query, 'do='. self::$PAGE_TOOLS)) {
+        if (startsWith($query, 'do=' . self::$PAGE_TOOLS)) {
            return self::$PAGE_TOOLS;
        }
-        if (startsWith($query, 'do='. self::$PAGE_CHANGEPASSWORD)) {
+        if (startsWith($query, 'do=' . self::$PAGE_CHANGEPASSWORD)) {
            return self::$PAGE_CHANGEPASSWORD;
        }
-        if (startsWith($query, 'do='. self::$PAGE_CONFIGURE)) {
+        if (startsWith($query, 'do=' . self::$PAGE_CONFIGURE)) {
            return self::$PAGE_CONFIGURE;
        }
-        if (startsWith($query, 'do='. self::$PAGE_CHANGETAG)) {
+        if (startsWith($query, 'do=' . self::$PAGE_CHANGETAG)) {
            return self::$PAGE_CHANGETAG;
        }
-        if (startsWith($query, 'do='. self::$PAGE_ADDLINK)) {
+        if (startsWith($query, 'do=' . self::$PAGE_ADDLINK)) {
            return self::$PAGE_ADDLINK;
        }
@@ -134,23 +149,27 @@ class Router
            return self::$PAGE_DELETELINK;
        }
-        if (startsWith($query, 'do='. self::$PAGE_EXPORT)) {
+        if (startsWith($query, 'do=' . self::$PAGE_PINLINK)) {
+            return self::$PAGE_PINLINK;
+        }
+        if (startsWith($query, 'do=' . self::$PAGE_EXPORT)) {
            return self::$PAGE_EXPORT;
        }
-        if (startsWith($query, 'do='. self::$PAGE_IMPORT)) {
+        if (startsWith($query, 'do=' . self::$PAGE_IMPORT)) {
            return self::$PAGE_IMPORT;
        }
-        if (startsWith($query, 'do='. self::$PAGE_PLUGINSADMIN)) {
+        if (startsWith($query, 'do=' . self::$PAGE_PLUGINSADMIN)) {
            return self::$PAGE_PLUGINSADMIN;
        }
-        if (startsWith($query, 'do='. self::$PAGE_SAVE_PLUGINSADMIN)) {
+        if (startsWith($query, 'do=' . self::$PAGE_SAVE_PLUGINSADMIN)) {
            return self::$PAGE_SAVE_PLUGINSADMIN;
        }
-        if (startsWith($query, 'do='. self::$GET_TOKEN)) {
+        if (startsWith($query, 'do=' . self::$GET_TOKEN)) {
            return self::$GET_TOKEN;
        }
diff --git a/application/Thumbnailer.php b/application/Thumbnailer.php
new file mode 100644
index 00000000..a23f98e9
--- /dev/null
+++ b/application/Thumbnailer.php
@@ -0,0 +1,130 @@
+<?php
+namespace Shaarli;
+use Shaarli\Config\ConfigManager;
+use WebThumbnailer\Application\ConfigManager as WTConfigManager;
+use WebThumbnailer\Exception\WebThumbnailerException;
+use WebThumbnailer\WebThumbnailer;
+/**
+ * Class Thumbnailer
+ *
+ * Utility class used to retrieve thumbnails using web-thumbnailer dependency.
+ */
+class Thumbnailer
+{
+    const COMMON_MEDIA_DOMAINS = [
+        'imgur.com',
+        'flickr.com',
+        'youtube.com',
+        'wikimedia.org',
+        'redd.it',
+        'gfycat.com',
+        'media.giphy.com',
+        'twitter.com',
+        'twimg.com',
+        'instagram.com',
+        'pinterest.com',
+        'pinterest.fr',
+        'tumblr.com',
+        'deviantart.com',
+    ];
+    const MODE_ALL = 'all';
+    const MODE_COMMON = 'common';
+    const MODE_NONE = 'none';
+    /**
+     * @var WebThumbnailer instance.
+     */
+    protected $wt;
+    /**
+     * @var ConfigManager instance.
+     */
+    protected $conf;
+    /**
+     * Thumbnailer constructor.
+     *
+     * @param ConfigManager $conf instance.
+     */
+    public function __construct($conf)
+    {
+        $this->conf = $conf;
+        if (! $this->checkRequirements()) {
+            $this->conf->set('thumbnails.enabled', false);
+            $this->conf->write(true);
+            // TODO: create a proper error handling system able to catch exceptions...
+            die(t(
+                'php-gd extension must be loaded to use thumbnails. '
+                .'Thumbnails are now disabled. Please reload the page.'
+            ));
+        }
+        $this->wt = new WebThumbnailer();
+        WTConfigManager::addFile('inc/web-thumbnailer.json');
+        $this->wt->maxWidth($this->conf->get('thumbnails.width'))
+                 ->maxHeight($this->conf->get('thumbnails.height'))
+                 ->crop(true)
+                 ->debug($this->conf->get('dev.debug', false));
+    }
+    /**
+     * Retrieve a thumbnail for given URL
+     *
+     * @param string $url where to look for a thumbnail.
+     *
+     * @return bool|string The thumbnail relative cache file path, or false if none has been found.
+     */
+    public function get($url)
+    {
+        if ($this->conf->get('thumbnails.mode') === self::MODE_COMMON
+            && ! $this->isCommonMediaOrImage($url)
+        ) {
+            return false;
+        }
+        try {
+            return $this->wt->thumbnail($url);
+        } catch (WebThumbnailerException $e) {
+            // Exceptions are only thrown in debug mode.
+            error_log(get_class($e) . ': ' . $e->getMessage());
+        }
+        return false;
+    }
+    /**
+     * We check weather the given URL is from a common media domain,
+     * or if the file extension is an image.
+     *
+     * @param string $url to check
+     *
+     * @return bool true if it's an image or from a common media domain, false otherwise.
+     */
+    public function isCommonMediaOrImage($url)
+    {
+        foreach (self::COMMON_MEDIA_DOMAINS as $domain) {
+            if (strpos($url, $domain) !== false) {
+                return true;
+            }
+        }
+        if (endsWith($url, '.jpg') || endsWith($url, '.png') || endsWith($url, '.jpeg')) {
+            return true;
+        }
+        return false;
+    }
+    /**
+     * Make sure that requirements are match to use thumbnails:
+     *   - php-gd is loaded
+     */
+    protected function checkRequirements()
+    {
+        return extension_loaded('gd');
+    }
+}
diff --git a/application/Utils.php b/application/Utils.php
index 97b12fcf..925e1a22 100644
--- a/application/Utils.php
+++ b/application/Utils.php
@@ -97,7 +97,7 @@ function escape($input)
    if (is_array($input)) {
        $out = array();
-        foreach($input as $key => $value) {
+        foreach ($input as $key => $value) {
            $out[$key] = escape($value);
        }
        return $out;
@@ -355,10 +355,13 @@ function return_bytes($val)
    $val = trim($val);
    $last = strtolower($val[strlen($val)-1]);
    $val = intval(substr($val, 0, -1));
-    switch($last) {
+    switch ($last) {
-        case 'g': $val *= 1024;
+        case 'g':
-        case 'm': $val *= 1024;
+            $val *= 1024;
-        case 'k': $val *= 1024;
+        case 'm':
+            $val *= 1024;
+        case 'k':
+            $val *= 1024;
    }
    return $val;
 }
@@ -452,6 +455,7 @@ function alphabetical_sort(&$data, $reverse = false, $byKeys = false)
 *
 * @return string Text translated.
 */
-function t($text, $nText = '', $nb = 1, $domain = 'shaarli') {
+function t($text, $nText = '', $nb = 1, $domain = 'shaarli')
+{
    return dn__($domain, $text, $nText, $nb);
 }
diff --git a/application/api/ApiMiddleware.php b/application/api/ApiMiddleware.php
index ff209393..5ffb8c6d 100644
--- a/application/api/ApiMiddleware.php
+++ b/application/api/ApiMiddleware.php
@@ -1,9 +1,8 @@
 <?php
 namespace Shaarli\Api;
-use Shaarli\Api\Exceptions\ApiException;
 use Shaarli\Api\Exceptions\ApiAuthorizationException;
+use Shaarli\Api\Exceptions\ApiException;
 use Shaarli\Config\ConfigManager;
 use Slim\Container;
 use Slim\Http\Request;
@@ -65,7 +64,7 @@ class ApiMiddleware
        try {
            $this->checkRequest($request);
            $response = $next($request, $response);
-        } catch(ApiException $e) {
+        } catch (ApiException $e) {
            $e->setResponse($response);
            $e->setDebug($this->conf->get('dev.debug', false));
            $response = $e->getApiResponse();
@@ -98,7 +97,8 @@ class ApiMiddleware
     *
     * @throws ApiAuthorizationException The token couldn't be validated.
     */
-    protected function checkToken($request) {
+    protected function checkToken($request)
+    {
        if (! $request->hasHeader('Authorization')) {
            throw new ApiAuthorizationException('JWT token not provided');
        }
@@ -126,7 +126,7 @@ class ApiMiddleware
     */
    protected function setLinkDb($conf)
    {
-        $linkDb = new \LinkDB(
+        $linkDb = new \Shaarli\Bookmark\LinkDB(
            $conf->get('resource.datastore'),
            true,
            $conf->get('privacy.hide_public_links'),
diff --git a/application/api/ApiUtils.php b/application/api/ApiUtils.php
index fc5ecaf1..1824b5d0 100644
--- a/application/api/ApiUtils.php
+++ b/application/api/ApiUtils.php
@@ -1,8 +1,8 @@
 <?php
 namespace Shaarli\Api;
-use Shaarli\Base64Url;
 use Shaarli\Api\Exceptions\ApiAuthorizationException;
+use Shaarli\Http\Base64Url;
 /**
 * REST API utilities
@@ -12,7 +12,7 @@ class ApiUtils
    /**
     * Validates a JWT token authenticity.
     *
-     * @param string $token JWT token extracted from the headers.
+     * @param string $token  JWT token extracted from the headers.
     * @param string $secret API secret set in the settings.
     *
     * @throws ApiAuthorizationException the token is not valid.
@@ -50,7 +50,7 @@ class ApiUtils
    /**
     * Format a Link for the REST API.
     *
-     * @param array $link Link data read from the datastore.
+     * @param array  $link     Link data read from the datastore.
     * @param string $indexUrl Shaarli's index URL (used for relative URL).
     *
     * @return array Link data formatted for the REST API.
diff --git a/application/api/controllers/ApiController.php b/application/api/controllers/ApiController.php
index 3be85b98..a6e7cbab 100644
--- a/application/api/controllers/ApiController.php
+++ b/application/api/controllers/ApiController.php
@@ -2,8 +2,9 @@
 namespace Shaarli\Api\Controllers;
+use Shaarli\Bookmark\LinkDB;
 use Shaarli\Config\ConfigManager;
-use \Slim\Container;
+use Slim\Container;
 /**
 * Abstract Class ApiController
@@ -25,12 +26,12 @@ abstract class ApiController
    protected $conf;
    /**
-     * @var \LinkDB
+     * @var LinkDB
     */
    protected $linkDb;
    /**
-     * @var \History
+     * @var HistoryController
     */
    protected $history;
@@ -41,7 +42,7 @@ abstract class ApiController
    /**
     * ApiController constructor.
-     * 
+     *
     * Note: enabling debug mode displays JSON with readable formatting.
     *
     * @param Container $ci Slim container.
diff --git a/application/api/controllers/History.php b/application/api/controllers/HistoryController.php
index 5cc453bf..9afcfa26 100644
--- a/application/api/controllers/History.php
+++ b/application/api/controllers/HistoryController.php
@@ -14,7 +14,7 @@ use Slim\Http\Response;
 *
 * @package Shaarli\Api\Controllers
 */
-class History extends ApiController
+class HistoryController extends ApiController
 {
    /**
     * Service providing operation regarding Shaarli datastore and settings.
@@ -35,8 +35,7 @@ class History extends ApiController
        $offset = $request->getParam('offset');
        if (empty($offset)) {
            $offset = 0;
-        }
+        } elseif (ctype_digit($offset)) {
-        elseif (ctype_digit($offset)) {
            $offset = (int) $offset;
        } else {
            throw new ApiBadParametersException('Invalid offset');
diff --git a/application/api/controllers/Info.php b/application/api/controllers/Info.php
index 25433f72..f37dcae5 100644
--- a/application/api/controllers/Info.php
+++ b/application/api/controllers/Info.php
@@ -7,7 +7,7 @@ use Slim\Http\Response;
 /**
 * Class Info
- * 
+ *
 * REST API Controller: /info
 *
 * @package Api\Controllers
@@ -17,7 +17,7 @@ class Info extends ApiController
 {
    /**
     * Service providing various information about Shaarli instance.
-     * 
+     *
     * @param Request  $request  Slim request.
     * @param Response $response Slim response.
     *
diff --git a/application/api/controllers/Tags.php b/application/api/controllers/Tags.php
index 6dd78750..82f3ef74 100644
--- a/application/api/controllers/Tags.php
+++ b/application/api/controllers/Tags.php
@@ -4,7 +4,6 @@ namespace Shaarli\Api\Controllers;
 use Shaarli\Api\ApiUtils;
 use Shaarli\Api\Exceptions\ApiBadParametersException;
-use Shaarli\Api\Exceptions\ApiLinkNotFoundException;
 use Shaarli\Api\Exceptions\ApiTagNotFoundException;
 use Slim\Http\Request;
 use Slim\Http\Response;
diff --git a/application/api/exceptions/ApiException.php b/application/api/exceptions/ApiException.php
index c8490e0c..d6b66323 100644
--- a/application/api/exceptions/ApiException.php
+++ b/application/api/exceptions/ApiException.php
@@ -10,7 +10,8 @@ use Slim\Http\Response;
 * Parent Exception related to the API, able to generate a valid Response (ResponseInterface).
 * Also can include various information in debug mode.
 */
-abstract class ApiException extends \Exception {
+abstract class ApiException extends \Exception
+{
    /**
     * @var Response instance from Slim.
@@ -27,7 +28,7 @@ abstract class ApiException extends \Exception {
     *
     * @return Response Final response to give.
     */
-    public abstract function getApiResponse();
+    abstract public function getApiResponse();
    /**
     * Creates ApiResponse body.
@@ -36,7 +37,8 @@ abstract class ApiException extends \Exception {
     *
     * @return array|string response body
     */
-    protected function getApiResponseBody() {
+    protected function getApiResponseBody()
+    {
        if ($this->debug !== true) {
            return $this->getMessage();
        }
diff --git a/application/api/exceptions/ApiLinkNotFoundException.php b/application/api/exceptions/ApiLinkNotFoundException.php
index de7e14f5..7c2bb56e 100644
--- a/application/api/exceptions/ApiLinkNotFoundException.php
+++ b/application/api/exceptions/ApiLinkNotFoundException.php
@@ -2,9 +2,6 @@
 namespace Shaarli\Api\Exceptions;
-use Slim\Http\Response;
 /**
 * Class ApiLinkNotFoundException
 *
diff --git a/application/api/exceptions/ApiTagNotFoundException.php b/application/api/exceptions/ApiTagNotFoundException.php
index eed5afa5..66ace8bf 100644
--- a/application/api/exceptions/ApiTagNotFoundException.php
+++ b/application/api/exceptions/ApiTagNotFoundException.php
@@ -2,9 +2,6 @@
 namespace Shaarli\Api\Exceptions;
-use Slim\Http\Response;
 /**
 * Class ApiTagNotFoundException
 *
diff --git a/application/LinkDB.php b/application/bookmark/LinkDB.php
index cd0f2967..c13a1141 100644
--- a/application/LinkDB.php
+++ b/application/bookmark/LinkDB.php
@@ -1,4 +1,15 @@
 <?php
+namespace Shaarli\Bookmark;
+use ArrayAccess;
+use Countable;
+use DateTime;
+use Iterator;
+use Shaarli\Bookmark\Exception\LinkNotFoundException;
+use Shaarli\Exceptions\IOException;
+use Shaarli\FileUtils;
 /**
 * Data storage for links.
 *
@@ -107,8 +118,8 @@ class LinkDB implements Iterator, Countable, ArrayAccess
        $hidePublicLinks,
        $redirector = '',
        $redirectorEncode = true
-    )
+    ) {
-    {
+    
        $this->datastore = $datastore;
        $this->loggedIn = $isLoggedIn;
        $this->hidePublicLinks = $hidePublicLinks;
@@ -138,7 +149,7 @@ class LinkDB implements Iterator, Countable, ArrayAccess
        if (!isset($value['id']) || empty($value['url'])) {
            die(t('Internal Error: A link should always have an id and URL.'));
        }
-        if (($offset !== null && ! is_int($offset)) || ! is_int($value['id'])) {
+        if (($offset !== null && !is_int($offset)) || !is_int($value['id'])) {
            die(t('You must specify an integer as a key.'));
        }
        if ($offset !== null && $offset !== $value['id']) {
@@ -248,28 +259,31 @@ class LinkDB implements Iterator, Countable, ArrayAccess
        $this->links = array();
        $link = array(
            'id' => 1,
-            'title'=> t('The personal, minimalist, super-fast, database free, bookmarking service'),
+            'title' => t('The personal, minimalist, super-fast, database free, bookmarking service'),
-            'url'=>'https://shaarli.readthedocs.io',
+            'url' => 'https://shaarli.readthedocs.io',
-            'description'=>t('Welcome to Shaarli! This is your first public bookmark. To edit or delete me, you must first login.
+            'description' => t(
+                'Welcome to Shaarli! This is your first public bookmark. '
+                . 'To edit or delete me, you must first login.
 To learn how to use Shaarli, consult the link "Documentation" at the bottom of this page.
-You use the community supported version of the original Shaarli project, by Sebastien Sauvage.'),
+You use the community supported version of the original Shaarli project, by Sebastien Sauvage.'
-            'private'=>0,
+            ),
-            'created'=> new DateTime(),
+            'private' => 0,
-            'tags'=>'opensource software'
+            'created' => new DateTime(),
+            'tags' => 'opensource software'
        );
        $link['shorturl'] = link_small_hash($link['created'], $link['id']);
        $this->links[1] = $link;
        $link = array(
            'id' => 0,
-            'title'=> t('My secret stuff... - Pastebin.com'),
+            'title' => t('My secret stuff... - Pastebin.com'),
-            'url'=>'http://sebsauvage.net/paste/?8434b27936c09649#bR7XsXhoTiLcqCpQbmOpBi3rq2zzQUC5hBI7ZT1O3x8=',
+            'url' => 'http://sebsauvage.net/paste/?8434b27936c09649#bR7XsXhoTiLcqCpQbmOpBi3rq2zzQUC5hBI7ZT1O3x8=',
-            'description'=> t('Shhhh! I\'m a private link only YOU can see. You can delete me too.'),
+            'description' => t('Shhhh! I\'m a private link only YOU can see. You can delete me too.'),
-            'private'=>1,
+            'private' => 1,
-            'created'=> new DateTime('1 minute ago'),
+            'created' => new DateTime('1 minute ago'),
-            'tags'=>'secretstuff',
+            'tags' => 'secretstuff',
        );
        $link['shorturl'] = link_small_hash($link['created'], $link['id']);
        $this->links[0] = $link;
@@ -295,7 +309,7 @@ You use the community supported version of the original Shaarli project, by Seba
        $toremove = array();
        foreach ($this->links as $key => &$link) {
-            if (! $this->loggedIn && $link['private'] != 0) {
+            if (!$this->loggedIn && $link['private'] != 0) {
                // Transition for not upgraded databases.
                unset($this->links[$key]);
                continue;
@@ -305,7 +319,7 @@ You use the community supported version of the original Shaarli project, by Seba
            sanitizeLink($link);
            // Remove private tags if the user is not logged in.
-            if (! $this->loggedIn) {
+            if (!$this->loggedIn) {
                $link['tags'] = preg_replace('/(^|\s+)\.[^($|\s)]+\s*/', ' ', $link['tags']);
            }
@@ -317,16 +331,15 @@ You use the community supported version of the original Shaarli project, by Seba
                } else {
                    $link['real_url'] .= $link['url'];
                }
-            }
+            } else {
-            else {
                $link['real_url'] = $link['url'];
            }
            // To be able to load links before running the update, and prepare the update
-            if (! isset($link['created'])) {
+            if (!isset($link['created'])) {
                $link['id'] = $link['linkdate'];
                $link['created'] = DateTime::createFromFormat(self::LINK_DATE_FORMAT, $link['linkdate']);
-                if (! empty($link['updated'])) {
+                if (!empty($link['updated'])) {
                    $link['updated'] = DateTime::createFromFormat(self::LINK_DATE_FORMAT, $link['updated']);
                }
                $link['shorturl'] = smallHash($link['linkdate']);
@@ -403,7 +416,8 @@ You use the community supported version of the original Shaarli project, by Seba
     *
     * @return array list of shaare found.
     */
-    public function filterDay($request) {
+    public function filterDay($request)
+    {
        $linkFilter = new LinkFilter($this->links);
        return $linkFilter->filter(LinkFilter::$FILTER_DAY, $request);
    }
@@ -411,17 +425,22 @@ You use the community supported version of the original Shaarli project, by Seba
    /**
     * Filter links according to search parameters.
     *
-     * @param array  $filterRequest Search request content. Supported keys:
+     * @param array  $filterRequest  Search request content. Supported keys:
     *                                - searchtags: list of tags
     *                                - searchterm: term search
-     * @param bool   $casesensitive Optional: Perform case sensitive filter
+     * @param bool   $casesensitive  Optional: Perform case sensitive filter
-     * @param string $visibility    return only all/private/public links
+     * @param string $visibility     return only all/private/public links
-     * @param string $untaggedonly  return only untagged links
+     * @param bool   $untaggedonly   return only untagged links
     *
     * @return array filtered links, all links if no suitable filter was provided.
     */
-    public function filterSearch($filterRequest = array(), $casesensitive = false, $visibility = 'all', $untaggedonly = false)
+    public function filterSearch(
-    {
+        $filterRequest = array(),
+        $casesensitive = false,
+        $visibility = 'all',
+        $untaggedonly = false
+    ) {
+    
        // Filter link database according to parameters.
        $searchtags = isset($filterRequest['searchtags']) ? escape($filterRequest['searchtags']) : '';
        $searchterm = isset($filterRequest['searchterm']) ? escape($filterRequest['searchterm']) : '';
@@ -437,8 +456,8 @@ You use the community supported version of the original Shaarli project, by Seba
    /**
     * Returns the list tags appearing in the links with the given tags
     *
-     * @param array $filteringTags tags selecting the links to consider
+     * @param array  $filteringTags tags selecting the links to consider
-     * @param string $visibility   process only all/private/public links
+     * @param string $visibility    process only all/private/public links
     *
     * @return array tag => linksCount
     */
@@ -492,8 +511,7 @@ You use the community supported version of the original Shaarli project, by Seba
        $delete = empty($to);
        // True for case-sensitive tag search.
        $linksToAlter = $this->filterSearch(['searchtags' => $from], true);
-        foreach($linksToAlter as $key => &$value)
+        foreach ($linksToAlter as $key => &$value) {
-        {
            $tags = preg_split('/\s+/', trim($value['tags']));
            if (($pos = array_search($from, $tags)) !== false) {
                if ($delete) {
@@ -536,7 +554,10 @@ You use the community supported version of the original Shaarli project, by Seba
    {
        $order = $order === 'ASC' ? -1 : 1;
        // Reorder array by dates.
-        usort($this->links, function($a, $b) use ($order) {
+        usort($this->links, function ($a, $b) use ($order) {
+            if (isset($a['sticky']) && isset($b['sticky']) && $a['sticky'] !== $b['sticky']) {
+                return $a['sticky'] ? -1 : 1;
+            }
            return $a['created'] < $b['created'] ? 1 * $order : -1 * $order;
        });
diff --git a/application/LinkFilter.php b/application/bookmark/LinkFilter.php
index e52239b8..9b966307 100644
--- a/application/LinkFilter.php
+++ b/application/bookmark/LinkFilter.php
@@ -1,5 +1,10 @@
 <?php
+namespace Shaarli\Bookmark;
+use Exception;
+use Shaarli\Bookmark\Exception\LinkNotFoundException;
 /**
 * Class LinkFilter.
 *
@@ -10,22 +15,22 @@ class LinkFilter
    /**
     * @var string permalinks.
     */
-    public static $FILTER_HASH   = 'permalink';
+    public static $FILTER_HASH = 'permalink';
    /**
     * @var string text search.
     */
-    public static $FILTER_TEXT   = 'fulltext';
+    public static $FILTER_TEXT = 'fulltext';
    /**
     * @var string tag filter.
     */
-    public static $FILTER_TAG    = 'tags';
+    public static $FILTER_TAG = 'tags';
    /**
     * @var string filter by day.
     */
-    public static $FILTER_DAY    = 'FILTER_DAY';
+    public static $FILTER_DAY = 'FILTER_DAY';
    /**
     * @var string Allowed characters for hashtags (regex syntax).
@@ -58,11 +63,11 @@ class LinkFilter
     */
    public function filter($type, $request, $casesensitive = false, $visibility = 'all', $untaggedonly = false)
    {
-        if (! in_array($visibility, ['all', 'public', 'private'])) {
+        if (!in_array($visibility, ['all', 'public', 'private'])) {
            $visibility = 'all';
        }
-        switch($type) {
+        switch ($type) {
            case self::$FILTER_HASH:
                return $this->filterSmallHash($request);
            case self::$FILTER_TAG | self::$FILTER_TEXT: // == "vuotext"
@@ -117,7 +122,7 @@ class LinkFilter
        foreach ($this->links as $key => $value) {
            if ($value['private'] && $visibility === 'private') {
                $out[$key] = $value;
-            } elseif (! $value['private'] && $visibility === 'public') {
+            } elseif (!$value['private'] && $visibility === 'public') {
                $out[$key] = $value;
            }
        }
@@ -132,7 +137,7 @@ class LinkFilter
     *
     * @return array $filtered array containing permalink data.
     *
-     * @throws LinkNotFoundException if the smallhash doesn't match any link.
+     * @throws \Shaarli\Bookmark\Exception\LinkNotFoundException if the smallhash doesn't match any link.
     */
    private function filterSmallHash($smallHash)
    {
@@ -169,7 +174,7 @@ class LinkFilter
     *  - see https://github.com/shaarli/Shaarli/issues/75 for examples
     *
     * @param string $searchterms search query.
-     * @param string $visibility Optional: return only all/private/public links.
+     * @param string $visibility  Optional: return only all/private/public links.
     *
     * @return array search results.
     */
@@ -205,10 +210,9 @@ class LinkFilter
        // Iterate over every stored link.
        foreach ($this->links as $id => $link) {
            // ignore non private links when 'privatonly' is on.
            if ($visibility !== 'all') {
-                if (! $link['private'] && $visibility === 'private') {
+                if (!$link['private'] && $visibility === 'private') {
                    continue;
                } elseif ($link['private'] && $visibility === 'public') {
                    continue;
@@ -251,17 +255,19 @@ class LinkFilter
    /**
     * generate a regex fragment out of a tag
+     *
     * @param string $tag to to generate regexs from. may start with '-' to negate, contain '*' as wildcard
+     *
     * @return string generated regex fragment
     */
    private static function tag2regex($tag)
    {
        $len = strlen($tag);
-        if(!$len || $tag === "-" || $tag === "*"){
+        if (!$len || $tag === "-" || $tag === "*") {
            // nothing to search, return empty regex
            return '';
        }
-        if($tag[0] === "-") {
+        if ($tag[0] === "-") {
            // query is negated
            $i = 1; // use offset to start after '-' character
            $regex = '(?!'; // create negative lookahead
@@ -271,14 +277,14 @@ class LinkFilter
        }
        $regex .= '.*(?:^| )'; // before tag may only be a space or the beginning
        // iterate over string, separating it into placeholder and content
-        for(; $i < $len; $i++){
+        for (; $i < $len; $i++) {
-            if($tag[$i] === '*'){
+            if ($tag[$i] === '*') {
                // placeholder found
                $regex .= '[^ ]*?';
            } else {
                // regular characters
                $offset = strpos($tag, '*', $i);
-                if($offset === false){
+                if ($offset === false) {
                    // no placeholder found, set offset to end of string
                    $offset = $len;
                }
@@ -310,19 +316,19 @@ class LinkFilter
    {
        // get single tags (we may get passed an array, even though the docs say different)
        $inputTags = $tags;
-        if(!is_array($tags)) {
+        if (!is_array($tags)) {
            // we got an input string, split tags
            $inputTags = preg_split('/(?:\s+)|,/', $inputTags, -1, PREG_SPLIT_NO_EMPTY);
        }
-        if(!count($inputTags)){
+        if (!count($inputTags)) {
            // no input tags
            return $this->noFilter($visibility);
        }
        // build regex from all tags
        $re = '/^' . implode(array_map("self::tag2regex", $inputTags)) . '.*$/';
-        if(!$casesensitive) {
+        if (!$casesensitive) {
            // make regex case insensitive
            $re .= 'i';
        }
@@ -335,14 +341,14 @@ class LinkFilter
            // check level of visibility
            // ignore non private links when 'privateonly' is on.
            if ($visibility !== 'all') {
-                if (! $link['private'] && $visibility === 'private') {
+                if (!$link['private'] && $visibility === 'private') {
                    continue;
                } elseif ($link['private'] && $visibility === 'public') {
                    continue;
                }
            }
            $search = $link['tags']; // build search string, start with tags of current link
-            if(strlen(trim($link['description'])) && strpos($link['description'], '#') !== false){
+            if (strlen(trim($link['description'])) && strpos($link['description'], '#') !== false) {
                // description given and at least one possible tag found
                $descTags = array();
                // find all tags in the form of #tag in the description
@@ -351,13 +357,13 @@ class LinkFilter
                    $link['description'],
                    $descTags
                );
-                if(count($descTags[1])){
+                if (count($descTags[1])) {
                    // there were some tags in the description, add them to the search string
                    $search .= ' ' . implode(' ', $descTags[1]);
                }
            };
            // match regular expression with search string
-            if(!preg_match($re, $search)){
+            if (!preg_match($re, $search)) {
                // this entry does _not_ match our regex
                continue;
            }
@@ -378,7 +384,7 @@ class LinkFilter
        $filtered = [];
        foreach ($this->links as $key => $link) {
            if ($visibility !== 'all') {
-                if (! $link['private'] && $visibility === 'private') {
+                if (!$link['private'] && $visibility === 'private') {
                    continue;
                } elseif ($link['private'] && $visibility === 'public') {
                    continue;
@@ -407,7 +413,7 @@ class LinkFilter
     */
    public function filterDay($day)
    {
-        if (! checkDateFormat('Ymd', $day)) {
+        if (!checkDateFormat('Ymd', $day)) {
            throw new Exception('Invalid date format');
        }
@@ -441,14 +447,3 @@ class LinkFilter
        return preg_split('/\s+/', $tagsOut, -1, PREG_SPLIT_NO_EMPTY);
    }
 }
-class LinkNotFoundException extends Exception
-{
-    /**
-     * LinkNotFoundException constructor.
-     */
-    public function __construct()
-    {
-        $this->message =  t('The link you are trying to reach does not exist or has been deleted.');
-    }
-}
diff --git a/application/LinkUtils.php b/application/bookmark/LinkUtils.php
index 4df5c0ca..de5b61cb 100644
--- a/application/LinkUtils.php
+++ b/application/bookmark/LinkUtils.php
@@ -1,11 +1,13 @@
 <?php
+use Shaarli\Bookmark\LinkDB;
 /**
 * Get cURL callback function for CURLOPT_WRITEFUNCTION
 *
 * @param string $charset     to extract from the downloaded page (reference)
 * @param string $title       to extract from the downloaded page (reference)
- * @param string $curlGetInfo Optionnaly overrides curl_getinfo function
+ * @param string $curlGetInfo Optionally overrides curl_getinfo function
 *
 * @return Closure
 */
@@ -23,7 +25,7 @@ function get_curl_download_callback(&$charset, &$title, $curlGetInfo = 'curl_get
     *
     * @return int|bool length of $data or false if we need to stop the download
     */
-    return function(&$ch, $data) use ($curlGetInfo, &$charset, &$title, &$isRedirected) {
+    return function (&$ch, $data) use ($curlGetInfo, &$charset, &$title, &$isRedirected) {
        $responseCode = $curlGetInfo($ch, CURLINFO_RESPONSE_CODE);
        if (!empty($responseCode) && in_array($responseCode, [301, 302])) {
            $isRedirected = true;
@@ -196,12 +198,13 @@ function space2nbsp($text)
 *
 * @param string $description shaare's description.
 * @param string $redirector  if a redirector is set, use it to gerenate links.
- * @param bool   $urlEncode  Use `urlencode()` on the URL after the redirector or not.
+ * @param bool   $urlEncode   Use `urlencode()` on the URL after the redirector or not.
 * @param string $indexUrl    URL to Shaarli's index.
 * @return string formatted description.
 */
-function format_description($description, $redirector = '', $urlEncode = true, $indexUrl = '') {
+function format_description($description, $redirector = '', $urlEncode = true, $indexUrl = '')
+{
    return nl2br(space2nbsp(hashtag_autolink(text2clickable($description, $redirector, $urlEncode), $indexUrl)));
 }
diff --git a/application/bookmark/exception/LinkNotFoundException.php b/application/bookmark/exception/LinkNotFoundException.php
new file mode 100644
index 00000000..f9414428
--- /dev/null
+++ b/application/bookmark/exception/LinkNotFoundException.php
@@ -0,0 +1,15 @@
+<?php
+namespace Shaarli\Bookmark\Exception;
+use Exception;
+class LinkNotFoundException extends Exception
+{
+    /**
+     * LinkNotFoundException constructor.
+     */
+    public function __construct()
+    {
+        $this->message = t('The link you are trying to reach does not exist or has been deleted.');
+    }
+}
diff --git a/application/config/ConfigJson.php b/application/config/ConfigJson.php
index 8c8d5610..4509357c 100644
--- a/application/config/ConfigJson.php
+++ b/application/config/ConfigJson.php
@@ -47,7 +47,7 @@ class ConfigJson implements ConfigIO
        $print = defined('JSON_PRETTY_PRINT') ? JSON_PRETTY_PRINT : 0;
        $data = self::getPhpHeaders() . json_encode($conf, $print) . self::getPhpSuffix();
        if (!file_put_contents($filepath, $data)) {
-            throw new \IOException(
+            throw new \Shaarli\Exceptions\IOException(
                $filepath,
                t('Shaarli could not create the config file. '.
                  'Please make sure Shaarli has the right to write in the folder is it installed in.')
diff --git a/application/config/ConfigManager.php b/application/config/ConfigManager.php
index 82f4a368..e6c35073 100644
--- a/application/config/ConfigManager.php
+++ b/application/config/ConfigManager.php
@@ -148,6 +148,33 @@ class ConfigManager
    }
    /**
+     * Remove a config element from the config file.
+     *
+     * @param string $setting    Asked setting, keys separated with dots.
+     * @param bool   $write      Write the new setting in the config file, default false.
+     * @param bool   $isLoggedIn User login state, default false.
+     *
+     * @throws \Exception Invalid
+     */
+    public function remove($setting, $write = false, $isLoggedIn = false)
+    {
+        if (empty($setting) || ! is_string($setting)) {
+            throw new \Exception(t('Invalid setting key parameter. String expected, got: '). gettype($setting));
+        }
+        // During the ConfigIO transition, map legacy settings to the new ones.
+        if ($this->configIO instanceof ConfigPhp && isset(ConfigPhp::$LEGACY_KEYS_MAPPING[$setting])) {
+            $setting = ConfigPhp::$LEGACY_KEYS_MAPPING[$setting];
+        }
+        $settings = explode('.', $setting);
+        self::removeConfig($settings, $this->loadedConfig);
+        if ($write) {
+            $this->write($isLoggedIn);
+        }
+    }
+    /**
     * Check if a settings exists.
     *
     * Supports nested settings with dot separated keys.
@@ -180,7 +207,7 @@ class ConfigManager
     *
     * @throws MissingFieldConfigException: a mandatory field has not been provided in $conf.
     * @throws UnauthorizedConfigException: user is not authorize to change configuration.
-     * @throws \IOException: an error occurred while writing the new config file.
+     * @throws \Shaarli\Exceptions\IOException: an error occurred while writing the new config file.
     */
    public function write($isLoggedIn)
    {
@@ -272,7 +299,7 @@ class ConfigManager
     *
     * @param array $settings Ordered array which contains keys to find.
     * @param mixed $value
-     * @param array $conf   Loaded settings, then sub-array.
+     * @param array $conf     Loaded settings, then sub-array.
     *
     * @return mixed Found setting or NOT_FOUND flag.
     */
@@ -290,6 +317,27 @@ class ConfigManager
    }
    /**
+     * Recursive function which find asked setting in the loaded config and deletes it.
+     *
+     * @param array $settings Ordered array which contains keys to find.
+     * @param array $conf     Loaded settings, then sub-array.
+     *
+     * @return mixed Found setting or NOT_FOUND flag.
+     */
+    protected static function removeConfig($settings, &$conf)
+    {
+        if (!is_array($settings) || count($settings) == 0) {
+            return self::$NOT_FOUND;
+        }
+        $setting = array_shift($settings);
+        if (count($settings) > 0) {
+            return self::removeConfig($settings, $conf[$setting]);
+        }
+        unset($conf[$setting]);
+    }
+    /**
     * Set a bunch of default values allowing Shaarli to start without a config file.
     */
    protected function setDefaultValues()
@@ -333,12 +381,12 @@ class ConfigManager
        // default state of the 'remember me' checkbox of the login form
        $this->setEmpty('privacy.remember_user_default', true);
-        $this->setEmpty('thumbnail.enable_thumbnails', true);
-        $this->setEmpty('thumbnail.enable_localcache', true);
        $this->setEmpty('redirector.url', '');
        $this->setEmpty('redirector.encode_url', true);
+        $this->setEmpty('thumbnails.width', '125');
+        $this->setEmpty('thumbnails.height', '90');
        $this->setEmpty('translation.language', 'auto');
        $this->setEmpty('translation.mode', 'php');
        $this->setEmpty('translation.extensions', []);
diff --git a/application/config/ConfigPhp.php b/application/config/ConfigPhp.php
index 8add8bcd..cad34594 100644
--- a/application/config/ConfigPhp.php
+++ b/application/config/ConfigPhp.php
@@ -27,7 +27,7 @@ class ConfigPhp implements ConfigIO
    /**
     * Map legacy config keys with the new ones.
     * If ConfigPhp is used, getting <newkey> will actually look for <legacykey>.
-     * The Updater will use this array to transform keys when switching to JSON.
+     * The updater will use this array to transform keys when switching to JSON.
     *
     * @var array current key => legacy key.
     */
@@ -104,19 +104,27 @@ class ConfigPhp implements ConfigIO
        // Store all $conf['config']
        foreach ($conf['config'] as $key => $value) {
-            $configStr .= '$GLOBALS[\'config\'][\''. $key .'\'] = '.var_export($conf['config'][$key], true).';'. PHP_EOL;
+            $configStr .= '$GLOBALS[\'config\'][\''
+                . $key
+                .'\'] = '
+                .var_export($conf['config'][$key], true).';'
+                . PHP_EOL;
        }
        if (isset($conf['plugins'])) {
            foreach ($conf['plugins'] as $key => $value) {
-                $configStr .= '$GLOBALS[\'plugins\'][\''. $key .'\'] = '.var_export($conf['plugins'][$key], true).';'. PHP_EOL;
+                $configStr .= '$GLOBALS[\'plugins\'][\''
+                    . $key
+                    .'\'] = '
+                    .var_export($conf['plugins'][$key], true).';'
+                    . PHP_EOL;
            }
        }
        if (!file_put_contents($filepath, $configStr)
            || strcmp(file_get_contents($filepath), $configStr) != 0
        ) {
-            throw new \IOException(
+            throw new \Shaarli\Exceptions\IOException(
                $filepath,
                t('Shaarli could not create the config file. '.
                  'Please make sure Shaarli has the right to write in the folder is it installed in.')
diff --git a/application/config/ConfigPlugin.php b/application/config/ConfigPlugin.php
index b3d9752b..dbb24937 100644
--- a/application/config/ConfigPlugin.php
+++ b/application/config/ConfigPlugin.php
@@ -34,8 +34,7 @@ function save_plugin_config($formData)
        // If there is no order, it means a disabled plugin has been enabled.
        if (isset($formData['order_' . $key])) {
            $plugins[(int) $formData['order_' . $key]] = $key;
-        }
+        } else {
-        else {
            $newEnabledPlugins[] = $key;
        }
    }
diff --git a/application/exceptions/IOException.php b/application/exceptions/IOException.php
index 18e46b77..2aa25e5c 100644
--- a/application/exceptions/IOException.php
+++ b/application/exceptions/IOException.php
@@ -1,4 +1,7 @@
 <?php
+namespace Shaarli\Exceptions;
+use Exception;
 /**
 * Exception class thrown when a filesystem access failure happens
@@ -17,6 +20,6 @@ class IOException extends Exception
    {
        $this->path = $path;
        $this->message = empty($message) ? t('Error accessing') : $message;
-        $this->message .= ' "' . $this->path .'"';
+        $this->message .= ' "' . $this->path . '"';
    }
 }
diff --git a/application/Cache.php b/application/feed/Cache.php
index e5d43e61..e5d43e61 100644
--- a/application/Cache.php
+++ b/application/feed/Cache.php
diff --git a/application/CachedPage.php b/application/feed/CachedPage.php
index e11cc52d..d809bdd9 100644
--- a/application/CachedPage.php
+++ b/application/feed/CachedPage.php
@@ -1,4 +1,7 @@
 <?php
+namespace Shaarli\Feed;
 /**
 * Simple cache system, mainly for the RSS/ATOM feeds
 */
@@ -24,7 +27,7 @@ class CachedPage
    {
        // TODO: check write access to the cache directory
        $this->cacheDir = $cacheDir;
-        $this->filename = $this->cacheDir.'/'.sha1($url).'.cache';
+        $this->filename = $this->cacheDir . '/' . sha1($url) . '.cache';
        $this->shouldBeCached = $shouldBeCached;
    }
diff --git a/application/FeedBuilder.php b/application/feed/FeedBuilder.php
index ebae18b4..b66f2f91 100644
--- a/application/FeedBuilder.php
+++ b/application/feed/FeedBuilder.php
@@ -1,4 +1,7 @@
 <?php
+namespace Shaarli\Feed;
+use DateTime;
 /**
 * FeedBuilder class.
@@ -28,7 +31,7 @@ class FeedBuilder
    public static $DEFAULT_NB_LINKS = 50;
    /**
-     * @var LinkDB instance.
+     * @var \Shaarli\Bookmark\LinkDB instance.
     */
    protected $linkDB;
@@ -38,12 +41,12 @@ class FeedBuilder
    protected $feedType;
    /**
-     * @var array $_SERVER.
+     * @var array $_SERVER
     */
    protected $serverInfo;
    /**
-     * @var array $_GET.
+     * @var array $_GET
     */
    protected $userInput;
@@ -75,11 +78,12 @@ class FeedBuilder
    /**
     * Feed constructor.
     *
-     * @param LinkDB  $linkDB        LinkDB instance.
+     * @param \Shaarli\Bookmark\LinkDB $linkDB     LinkDB instance.
-     * @param string  $feedType      Type of feed.
+     * @param string                   $feedType   Type of feed.
-     * @param array   $serverInfo    $_SERVER.
+     * @param array                    $serverInfo $_SERVER.
-     * @param array   $userInput     $_GET.
+     * @param array                    $userInput  $_GET.
-     * @param boolean $isLoggedIn True if the user is currently logged in, false otherwise.
+     * @param boolean                  $isLoggedIn True if the user is currently logged in,
+     *                                             false otherwise.
     */
    public function __construct($linkDB, $feedType, $serverInfo, $userInput, $isLoggedIn)
    {
@@ -124,7 +128,7 @@ class FeedBuilder
        $data['show_dates'] = !$this->hideDates || $this->isLoggedIn;
        // Remove leading slash from REQUEST_URI.
        $data['self_link'] = escape(server_url($this->serverInfo))
-                           . escape($this->serverInfo['REQUEST_URI']);
+            . escape($this->serverInfo['REQUEST_URI']);
        $data['index_url'] = $pageaddr;
        $data['usepermalinks'] = $this->usePermalinks === true;
        $data['links'] = $linkDisplayed;
@@ -142,18 +146,18 @@ class FeedBuilder
     */
    protected function buildItem($link, $pageaddr)
    {
-        $link['guid'] = $pageaddr .'?'. $link['shorturl'];
+        $link['guid'] = $pageaddr . '?' . $link['shorturl'];
        // Check for both signs of a note: starting with ? and 7 chars long.
        if ($link['url'][0] === '?' && strlen($link['url']) === 7) {
            $link['url'] = $pageaddr . $link['url'];
        }
        if ($this->usePermalinks === true) {
-            $permalink = '<a href="'. $link['url'] .'" title="'. t('Direct link') .'">'. t('Direct link') .'</a>';
+            $permalink = '<a href="' . $link['url'] . '" title="' . t('Direct link') . '">' . t('Direct link') . '</a>';
        } else {
-            $permalink = '<a href="'. $link['guid'] .'" title="'. t('Permalink') .'">'. t('Permalink') .'</a>';
+            $permalink = '<a href="' . $link['guid'] . '" title="' . t('Permalink') . '">' . t('Permalink') . '</a>';
        }
-        $link['description']  = format_description($link['description'], '', false, $pageaddr);
+        $link['description'] = format_description($link['description'], '', false, $pageaddr);
-        $link['description'] .= PHP_EOL .'<br>&#8212; '. $permalink;
+        $link['description'] .= PHP_EOL . '<br>&#8212; ' . $permalink;
        $pubDate = $link['created'];
        $link['pub_iso_date'] = $this->getIsoDate($pubDate);
@@ -163,7 +167,7 @@ class FeedBuilder
            $upDate = $link['updated'];
            $link['up_iso_date'] = $this->getIsoDate($upDate, DateTime::ATOM);
        } else {
-            $link['up_iso_date'] = $this->getIsoDate($pubDate, DateTime::ATOM);;
+            $link['up_iso_date'] = $this->getIsoDate($pubDate, DateTime::ATOM);
        }
        // Save the more recent item.
@@ -222,11 +226,11 @@ class FeedBuilder
    public function getTypeLanguage()
    {
        // Use the locale do define the language, if available.
-        if (! empty($this->locale) && preg_match('/^\w{2}[_\-]\w{2}/', $this->locale)) {
+        if (!empty($this->locale) && preg_match('/^\w{2}[_\-]\w{2}/', $this->locale)) {
-            $length = ($this->feedType == self::$FEED_RSS) ? 5 : 2;
+            $length = ($this->feedType === self::$FEED_RSS) ? 5 : 2;
            return str_replace('_', '-', substr($this->locale, 0, $length));
        }
-        return ($this->feedType == self::$FEED_RSS) ? 'en-en' : 'en';
+        return ($this->feedType === self::$FEED_RSS) ? 'en-en' : 'en';
    }
    /**
@@ -261,7 +265,6 @@ class FeedBuilder
        }
        if ($this->feedType == self::$FEED_RSS) {
            return $date->format(DateTime::RSS);
        }
        return $date->format(DateTime::ATOM);
    }
@@ -287,7 +290,7 @@ class FeedBuilder
        }
        $intNb = intval($this->userInput['nb']);
-        if (! is_int($intNb) || $intNb == 0) {
+        if (!is_int($intNb) || $intNb == 0) {
            return self::$DEFAULT_NB_LINKS;
        }
diff --git a/application/Base64Url.php b/application/http/Base64Url.php
index 61590e43..33fa7c1f 100644
--- a/application/Base64Url.php
+++ b/application/http/Base64Url.php
@@ -1,7 +1,6 @@
 <?php
-namespace Shaarli;
+namespace Shaarli\Http;
 /**
 * URL-safe Base64 operations
@@ -17,7 +16,8 @@ class Base64Url
     *
     * @return string Base64Url-encoded data
     */
-    public static function encode($data) {
+    public static function encode($data)
+    {
        return rtrim(strtr(base64_encode($data), '+/', '-_'), '=');
    }
@@ -28,7 +28,8 @@ class Base64Url
     *
     * @return string Decoded data
     */
-    public static function decode($data) {
+    public static function decode($data)
+    {
        return base64_decode(str_pad(strtr($data, '-_', '+/'), strlen($data) % 4, '=', STR_PAD_RIGHT));
    }
 }
diff --git a/application/HttpUtils.php b/application/http/HttpUtils.php
index e9282506..2ea9195d 100644
--- a/application/HttpUtils.php
+++ b/application/http/HttpUtils.php
@@ -1,4 +1,7 @@
 <?php
+use Shaarli\Http\Url;
 /**
 * GET an HTTP URL to retrieve its content
 * Uses the cURL library or a fallback method
@@ -7,7 +10,8 @@
 * @param int             $timeout           network timeout (in seconds)
 * @param int             $maxBytes          maximum downloaded bytes (default: 4 MiB)
 * @param callable|string $curlWriteFunction Optional callback called during the download (cURL CURLOPT_WRITEFUNCTION).
- *                                           Can be used to add download conditions on the headers (response code, content type, etc.).
+ *                                           Can be used to add download conditions on the
+ *                                           headers (response code, content type, etc.).
 *
 * @return array HTTP response headers, downloaded content
 *
@@ -37,7 +41,7 @@ function get_http_response($url, $timeout = 30, $maxBytes = 4194304, $curlWriteF
    $cleanUrl = $urlObj->idnToAscii();
    if (!filter_var($cleanUrl, FILTER_VALIDATE_URL) || !$urlObj->isHttp()) {
-        return array(array(0 => 'Invalid HTTP Url'), false);
+        return array(array(0 => 'Invalid HTTP UrlUtils'), false);
    }
    $userAgent =
@@ -64,29 +68,30 @@ function get_http_response($url, $timeout = 30, $maxBytes = 4194304, $curlWriteF
    }
    // General cURL settings
-    curl_setopt($ch, CURLOPT_AUTOREFERER,       true);
+    curl_setopt($ch, CURLOPT_AUTOREFERER, true);
-    curl_setopt($ch, CURLOPT_FOLLOWLOCATION,    true);
+    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
-    curl_setopt($ch, CURLOPT_HEADER,            true);
+    curl_setopt($ch, CURLOPT_HEADER, true);
    curl_setopt(
        $ch,
        CURLOPT_HTTPHEADER,
        array('Accept-Language: ' . $acceptLanguage)
    );
-    curl_setopt($ch, CURLOPT_MAXREDIRS,         $maxRedirs);
+    curl_setopt($ch, CURLOPT_MAXREDIRS, $maxRedirs);
-    curl_setopt($ch, CURLOPT_RETURNTRANSFER,    true);
+    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
-    curl_setopt($ch, CURLOPT_TIMEOUT,           $timeout);
+    curl_setopt($ch, CURLOPT_TIMEOUT, $timeout);
-    curl_setopt($ch, CURLOPT_USERAGENT,         $userAgent);
+    curl_setopt($ch, CURLOPT_USERAGENT, $userAgent);
    if (is_callable($curlWriteFunction)) {
        curl_setopt($ch, CURLOPT_WRITEFUNCTION, $curlWriteFunction);
    }
    // Max download size management
-    curl_setopt($ch, CURLOPT_BUFFERSIZE,        1024*16);
+    curl_setopt($ch, CURLOPT_BUFFERSIZE, 1024*16);
-    curl_setopt($ch, CURLOPT_NOPROGRESS,        false);
+    curl_setopt($ch, CURLOPT_NOPROGRESS, false);
-    curl_setopt($ch, CURLOPT_PROGRESSFUNCTION,
+    curl_setopt(
-        function($arg0, $arg1, $arg2, $arg3, $arg4 = 0) use ($maxBytes)
+        $ch,
-        {
+        CURLOPT_PROGRESSFUNCTION,
+        function ($arg0, $arg1, $arg2, $arg3, $arg4 = 0) use ($maxBytes) {
            if (version_compare(phpversion(), '5.5', '<')) {
                // PHP version lower than 5.5
                // Callback has 4 arguments
@@ -232,7 +237,6 @@ function get_redirected_headers($url, $redirectionLimit = 3)
        && !empty($headers)
        && (strpos($headers[0], '301') !== false || strpos($headers[0], '302') !== false)
        && !empty($headers['Location'])) {
        $redirection = is_array($headers['Location']) ? end($headers['Location']) : $headers['Location'];
        if ($redirection != $url) {
            $redirection = getAbsoluteUrl($url, $redirection);
diff --git a/application/Url.php b/application/http/Url.php
index 6b9870f0..90444a2f 100644
--- a/application/Url.php
+++ b/application/http/Url.php
@@ -1,91 +1,6 @@
 <?php
-/**
- * Converts an array-represented URL to a string
- *
- * Source: http://php.net/manual/en/function.parse-url.php#106731
- *
- * @see http://php.net/manual/en/function.parse-url.php
- *
- * @param array $parsedUrl an array-represented URL
- *
- * @return string the string representation of the URL
- */
-function unparse_url($parsedUrl)
-{
-    $scheme   = isset($parsedUrl['scheme']) ? $parsedUrl['scheme'].'://' : '';
-    $host     = isset($parsedUrl['host']) ? $parsedUrl['host'] : '';
-    $port     = isset($parsedUrl['port']) ? ':'.$parsedUrl['port'] : '';
-    $user     = isset($parsedUrl['user']) ? $parsedUrl['user'] : '';
-    $pass     = isset($parsedUrl['pass']) ? ':'.$parsedUrl['pass']  : '';
-    $pass     = ($user || $pass) ? "$pass@" : '';
-    $path     = isset($parsedUrl['path']) ? $parsedUrl['path'] : '';
-    $query    = isset($parsedUrl['query']) ? '?'.$parsedUrl['query'] : '';
-    $fragment = isset($parsedUrl['fragment']) ? '#'.$parsedUrl['fragment'] : '';
-    return "$scheme$user$pass$host$port$path$query$fragment";
-}
-/**
- * Removes undesired query parameters and fragments
- *
- * @param string url Url to be cleaned
- *
- * @return string the string representation of this URL after cleanup
- */
-function cleanup_url($url)
-{
-  $obj_url = new Url($url);
-  return $obj_url->cleanup();
-}
-/**
+namespace Shaarli\Http;
- * Get URL scheme.
- *
- * @param string url Url for which the scheme is requested
- *
- * @return mixed the URL scheme or false if none is provided.
- */
-function get_url_scheme($url)
-{
-  $obj_url = new Url($url);
-  return $obj_url->getScheme();
-}
-/**
- * Adds a trailing slash at the end of URL if necessary.
- *
- * @param string $url URL to check/edit.
- *
- * @return string $url URL with a end trailing slash.
- */
-function add_trailing_slash($url)
-{
-    return $url . (!endsWith($url, '/') ? '/' : '');
-}
-/**
- * Replace not whitelisted protocols by 'http://' from given URL.
- *
- * @param string $url       URL to clean
- * @param array  $protocols List of allowed protocols (aside from http(s)).
- *
- * @return string URL with allowed protocol
- */
-function whitelist_protocols($url, $protocols)
-{
-    if (startsWith($url, '?') || startsWith($url, '/')) {
-        return $url;
-    }
-    $protocols = array_merge(['http', 'https'], $protocols);
-    $protocol = preg_match('#^(\w+):/?/?#', $url, $match);
-    // Protocol not allowed: we remove it and replace it with http
-    if ($protocol === 1 && ! in_array($match[1], $protocols)) {
-        $url = str_replace($match[0], 'http://', $url);
-    } elseif ($protocol !== 1) {
-        $url = 'http://' . $url;
-    }
-    return $url;
-}
 /**
 * URL representation and cleanup utilities
@@ -182,7 +97,7 @@ class Url
        }
        return $input;
    }
-    
    /**
     * Returns a string representation of this URL
     */
@@ -196,7 +111,7 @@ class Url
     */
    protected function cleanupQuery()
    {
-        if (! isset($this->parts['query'])) {
+        if (!isset($this->parts['query'])) {
            return;
        }
@@ -217,14 +132,14 @@ class Url
        }
        $this->parts['query'] = implode('&', $queryParams);
-    }    
+    }
    /**
     * Removes undesired fragments
     */
    protected function cleanupFragment()
    {
-        if (! isset($this->parts['fragment'])) {
+        if (!isset($this->parts['fragment'])) {
            return;
        }
@@ -257,7 +172,7 @@ class Url
    public function idnToAscii()
    {
        $out = $this->cleanup();
-        if (! function_exists('idn_to_ascii') || ! isset($this->parts['host'])) {
+        if (!function_exists('idn_to_ascii') || !isset($this->parts['host'])) {
            return $out;
        }
        $asciiHost = idn_to_ascii($this->parts['host'], 0, INTL_IDNA_VARIANT_UTS46);
@@ -269,7 +184,8 @@ class Url
     *
     * @return string the URL scheme or false if none is provided.
     */
-    public function getScheme() {
+    public function getScheme()
+    {
        if (!isset($this->parts['scheme'])) {
            return false;
        }
@@ -281,7 +197,8 @@ class Url
     *
     * @return string the URL host or false if none is provided.
     */
-    public function getHost() {
+    public function getHost()
+    {
        if (empty($this->parts['host'])) {
            return false;
        }
@@ -289,11 +206,12 @@ class Url
    }
    /**
-     * Test if the Url is an HTTP one.
+     * Test if the UrlUtils is an HTTP one.
     *
     * @return true is HTTP, false otherwise.
     */
-    public function isHttp() {
+    public function isHttp()
+    {
        return strpos(strtolower($this->parts['scheme']), 'http') !== false;
    }
 }
diff --git a/application/http/UrlUtils.php b/application/http/UrlUtils.php
new file mode 100644
index 00000000..4bc84b82
--- /dev/null
+++ b/application/http/UrlUtils.php
@@ -0,0 +1,88 @@
+<?php
+/**
+ * Converts an array-represented URL to a string
+ *
+ * Source: http://php.net/manual/en/function.parse-url.php#106731
+ *
+ * @see http://php.net/manual/en/function.parse-url.php
+ *
+ * @param array $parsedUrl an array-represented URL
+ *
+ * @return string the string representation of the URL
+ */
+function unparse_url($parsedUrl)
+{
+    $scheme   = isset($parsedUrl['scheme']) ? $parsedUrl['scheme'].'://' : '';
+    $host     = isset($parsedUrl['host']) ? $parsedUrl['host'] : '';
+    $port     = isset($parsedUrl['port']) ? ':'.$parsedUrl['port'] : '';
+    $user     = isset($parsedUrl['user']) ? $parsedUrl['user'] : '';
+    $pass     = isset($parsedUrl['pass']) ? ':'.$parsedUrl['pass']  : '';
+    $pass     = ($user || $pass) ? "$pass@" : '';
+    $path     = isset($parsedUrl['path']) ? $parsedUrl['path'] : '';
+    $query    = isset($parsedUrl['query']) ? '?'.$parsedUrl['query'] : '';
+    $fragment = isset($parsedUrl['fragment']) ? '#'.$parsedUrl['fragment'] : '';
+    return "$scheme$user$pass$host$port$path$query$fragment";
+}
+/**
+ * Removes undesired query parameters and fragments
+ *
+ * @param string url UrlUtils to be cleaned
+ *
+ * @return string the string representation of this URL after cleanup
+ */
+function cleanup_url($url)
+{
+    $obj_url = new \Shaarli\Http\Url($url);
+    return $obj_url->cleanup();
+}
+/**
+ * Get URL scheme.
+ *
+ * @param string url UrlUtils for which the scheme is requested
+ *
+ * @return mixed the URL scheme or false if none is provided.
+ */
+function get_url_scheme($url)
+{
+    $obj_url = new \Shaarli\Http\Url($url);
+    return $obj_url->getScheme();
+}
+/**
+ * Adds a trailing slash at the end of URL if necessary.
+ *
+ * @param string $url URL to check/edit.
+ *
+ * @return string $url URL with a end trailing slash.
+ */
+function add_trailing_slash($url)
+{
+    return $url . (!endsWith($url, '/') ? '/' : '');
+}
+/**
+ * Replace not whitelisted protocols by 'http://' from given URL.
+ *
+ * @param string $url       URL to clean
+ * @param array  $protocols List of allowed protocols (aside from http(s)).
+ *
+ * @return string URL with allowed protocol
+ */
+function whitelist_protocols($url, $protocols)
+{
+    if (startsWith($url, '?') || startsWith($url, '/')) {
+        return $url;
+    }
+    $protocols = array_merge(['http', 'https'], $protocols);
+    $protocol = preg_match('#^(\w+):/?/?#', $url, $match);
+    // Protocol not allowed: we remove it and replace it with http
+    if ($protocol === 1 && ! in_array($match[1], $protocols)) {
+        $url = str_replace($match[0], 'http://', $url);
+    } elseif ($protocol !== 1) {
+        $url = 'http://' . $url;
+    }
+    return $url;
+}
diff --git a/application/NetscapeBookmarkUtils.php b/application/netscape/NetscapeBookmarkUtils.php
index b4d16d00..2fb1a4a6 100644
--- a/application/NetscapeBookmarkUtils.php
+++ b/application/netscape/NetscapeBookmarkUtils.php
@@ -1,9 +1,16 @@
 <?php
+namespace Shaarli\Netscape;
+use DateTime;
+use DateTimeZone;
+use Exception;
+use Katzgrau\KLogger\Logger;
 use Psr\Log\LogLevel;
+use Shaarli\Bookmark\LinkDB;
 use Shaarli\Config\ConfigManager;
+use Shaarli\History;
 use Shaarli\NetscapeBookmarkParser\NetscapeBookmarkParser;
-use Katzgrau\KLogger\Logger;
 /**
 * Utilities to import and export bookmarks using the Netscape format
@@ -31,8 +38,8 @@ class NetscapeBookmarkUtils
    public static function filterAndFormat($linkDb, $selection, $prependNoteUrl, $indexUrl)
    {
        // see tpl/export.html for possible values
-        if (! in_array($selection, array('all', 'public', 'private'))) {
+        if (!in_array($selection, array('all', 'public', 'private'))) {
-            throw new Exception(t('Invalid export selection:') .' "'.$selection.'"');
+            throw new Exception(t('Invalid export selection:') . ' "' . $selection . '"');
        }
        $bookmarkLinks = array();
@@ -72,18 +79,20 @@ class NetscapeBookmarkUtils
    private static function importStatus(
        $filename,
        $filesize,
-        $importCount=0,
+        $importCount = 0,
-        $overwriteCount=0,
+        $overwriteCount = 0,
-        $skipCount=0,
+        $skipCount = 0,
-        $duration=0
+        $duration = 0
-    )
+    ) {
-    {
        $status = sprintf(t('File %s (%d bytes) '), $filename, $filesize);
        if ($importCount == 0 && $overwriteCount == 0 && $skipCount == 0) {
            $status .= t('has an unknown file format. Nothing was imported.');
        } else {
            $status .= vsprintf(
-                t('was successfully processed in %d seconds: %d links imported, %d links overwritten, %d links skipped.'),
+                t(
+                    'was successfully processed in %d seconds: '
+                    . '%d links imported, %d links overwritten, %d links skipped.'
+                ),
                [$duration, $importCount, $overwriteCount, $skipCount]
            );
        }
@@ -93,11 +102,11 @@ class NetscapeBookmarkUtils
    /**
     * Imports Web bookmarks from an uploaded Netscape bookmark dump
     *
-     * @param array         $post      Server $_POST parameters
+     * @param array         $post    Server $_POST parameters
-     * @param array         $files     Server $_FILES parameters
+     * @param array         $files   Server $_FILES parameters
-     * @param LinkDB        $linkDb    Loaded LinkDB instance
+     * @param LinkDB        $linkDb  Loaded LinkDB instance
-     * @param ConfigManager $conf      instance
+     * @param ConfigManager $conf    instance
-     * @param History       $history   History instance
+     * @param History       $history History instance
     *
     * @return string Summary of the bookmark import status
     */
@@ -113,7 +122,7 @@ class NetscapeBookmarkUtils
        }
        // Overwrite existing links?
-        $overwrite = ! empty($post['overwrite']);
+        $overwrite = !empty($post['overwrite']);
        // Add tags to all imported links?
        if (empty($post['default_tags'])) {
@@ -136,7 +145,7 @@ class NetscapeBookmarkUtils
        );
        $logger = new Logger(
            $conf->get('resource.data_dir'),
-            ! $conf->get('dev.debug') ? LogLevel::INFO : LogLevel::DEBUG,
+            !$conf->get('dev.debug') ? LogLevel::INFO : LogLevel::DEBUG,
            [
                'prefix' => 'import.',
                'extension' => 'log',
@@ -191,7 +200,7 @@ class NetscapeBookmarkUtils
            }
            // Add a new link - @ used for UNIX timestamps
-            $newLinkDate = new DateTime('@'.strval($bkm['time']));
+            $newLinkDate = new DateTime('@' . strval($bkm['time']));
            $newLinkDate->setTimezone(new DateTimeZone(date_default_timezone_get()));
            $newLink['created'] = $newLinkDate;
            $newLink['id'] = $linkDb->getNextId();
diff --git a/application/PluginManager.php b/application/plugin/PluginManager.php
index cf603845..f7b24a8e 100644
--- a/application/PluginManager.php
+++ b/application/plugin/PluginManager.php
@@ -1,4 +1,8 @@
 <?php
+namespace Shaarli\Plugin;
+use Shaarli\Config\ConfigManager;
+use Shaarli\Plugin\Exception\PluginFileNotFoundException;
 /**
 * Class PluginManager
@@ -9,12 +13,14 @@ class PluginManager
 {
    /**
     * List of authorized plugins from configuration file.
+     *
     * @var array $authorizedPlugins
     */
    private $authorizedPlugins;
    /**
     * List of loaded plugins.
+     *
     * @var array $loadedPlugins
     */
    private $loadedPlugins = array();
@@ -31,12 +37,14 @@ class PluginManager
    /**
     * Plugins subdirectory.
+     *
     * @var string $PLUGINS_PATH
     */
    public static $PLUGINS_PATH = 'plugins';
    /**
     * Plugins meta files extension.
+     *
     * @var string $META_EXT
     */
    public static $META_EXT = 'meta';
@@ -75,8 +83,7 @@ class PluginManager
            try {
                $this->loadPlugin($dirs[$index], $plugin);
-            }
+            } catch (PluginFileNotFoundException $e) {
-            catch (PluginFileNotFoundException $e) {
                error_log($e->getMessage());
            }
        }
@@ -85,9 +92,9 @@ class PluginManager
    /**
     * Execute all plugins registered hook.
     *
-     * @param string        $hook   name of the hook to trigger.
+     * @param string $hook   name of the hook to trigger.
-     * @param array         $data   list of data to manipulate passed by reference.
+     * @param array  $data   list of data to manipulate passed by reference.
-     * @param array         $params additional parameters such as page target.
+     * @param array  $params additional parameters such as page target.
     *
     * @return void
     */
@@ -119,7 +126,7 @@ class PluginManager
     * @param string $pluginName plugin's name.
     *
     * @return void
-     * @throws PluginFileNotFoundException - plugin files not found.
+     * @throws \Shaarli\Plugin\Exception\PluginFileNotFoundException - plugin files not found.
     */
    private function loadPlugin($dir, $pluginName)
    {
@@ -205,8 +212,8 @@ class PluginManager
                $metaData[$plugin]['parameters'][$param]['value'] = '';
                // Optional parameter description in parameter.PARAM_NAME=
-                if (isset($metaData[$plugin]['parameter.'. $param])) {
+                if (isset($metaData[$plugin]['parameter.' . $param])) {
-                    $metaData[$plugin]['parameters'][$param]['desc'] = t($metaData[$plugin]['parameter.'. $param]);
+                    $metaData[$plugin]['parameters'][$param]['desc'] = t($metaData[$plugin]['parameter.' . $param]);
                }
            }
        }
@@ -224,22 +231,3 @@ class PluginManager
        return $this->errors;
    }
 }
-/**
- * Class PluginFileNotFoundException
- *
- * Raise when plugin files can't be found.
- */
-class PluginFileNotFoundException extends Exception
-{
-    /**
-     * Construct exception with plugin name.
-     * Generate message.
-     *
-     * @param string $pluginName name of the plugin not found
-     */
-    public function __construct($pluginName)
-    {
-        $this->message = sprintf(t('Plugin "%s" files not found.'), $pluginName);
-    }
-}
diff --git a/application/plugin/exception/PluginFileNotFoundException.php b/application/plugin/exception/PluginFileNotFoundException.php
new file mode 100644
index 00000000..e5386f02
--- /dev/null
+++ b/application/plugin/exception/PluginFileNotFoundException.php
@@ -0,0 +1,23 @@
+<?php
+namespace Shaarli\Plugin\Exception;
+use Exception;
+/**
+ * Class PluginFileNotFoundException
+ *
+ * Raise when plugin files can't be found.
+ */
+class PluginFileNotFoundException extends Exception
+{
+    /**
+     * Construct exception with plugin name.
+     * Generate message.
+     *
+     * @param string $pluginName name of the plugin not found
+     */
+    public function __construct($pluginName)
+    {
+        $this->message = sprintf(t('Plugin "%s" files not found.'), $pluginName);
+    }
+}
diff --git a/application/PageBuilder.php b/application/render/PageBuilder.php
index a4483870..0569b67f 100644
--- a/application/PageBuilder.php
+++ b/application/render/PageBuilder.php
@@ -1,6 +1,13 @@
 <?php
+namespace Shaarli\Render;
+use Exception;
+use RainTPL;
+use Shaarli\ApplicationUtils;
+use Shaarli\Bookmark\LinkDB;
 use Shaarli\Config\ConfigManager;
+use Shaarli\Thumbnailer;
 /**
 * This class is in charge of building the final page.
@@ -22,25 +29,40 @@ class PageBuilder
    protected $conf;
    /**
+     * @var array $_SESSION
+     */
+    protected $session;
+    /**
     * @var LinkDB $linkDB instance.
     */
    protected $linkDB;
-    
-    /** @var bool $isLoggedIn Whether the user is logged in **/
+    /**
+     * @var null|string XSRF token
+     */
+    protected $token;
+    /**
+     * @var bool $isLoggedIn Whether the user is logged in
+     */
    protected $isLoggedIn = false;
    /**
     * PageBuilder constructor.
     * $tpl is initialized at false for lazy loading.
     *
-     * @param ConfigManager $conf   Configuration Manager instance (reference).
+     * @param ConfigManager $conf       Configuration Manager instance (reference).
-     * @param LinkDB        $linkDB instance.
+     * @param array         $session    $_SESSION array
-     * @param string        $token  Session token
+     * @param LinkDB        $linkDB     instance.
+     * @param string        $token      Session token
+     * @param bool          $isLoggedIn
     */
-    public function __construct(&$conf, $linkDB = null, $token = null, $isLoggedIn = false)
+    public function __construct(&$conf, $session, $linkDB = null, $token = null, $isLoggedIn = false)
    {
        $this->tpl = false;
        $this->conf = $conf;
+        $this->session = $session;
        $this->linkDB = $linkDB;
        $this->token = $token;
        $this->isLoggedIn = $isLoggedIn;
@@ -64,7 +86,6 @@ class PageBuilder
            );
            $this->tpl->assign('newVersion', escape($version));
            $this->tpl->assign('versionError', '');
        } catch (Exception $exc) {
            logm($this->conf->get('resource.log'), $_SERVER['REMOTE_ADDR'], $exc->getMessage());
            $this->tpl->assign('newVersion', '');
@@ -87,8 +108,8 @@ class PageBuilder
            'version_hash',
            ApplicationUtils::getVersionHash(SHAARLI_VERSION, $this->conf->get('credentials.salt'))
        );
-        $this->tpl->assign('scripturl', index_url($_SERVER));
+        $this->tpl->assign('index_url', index_url($_SERVER));
-        $visibility = ! empty($_SESSION['visibility']) ? $_SESSION['visibility'] : '';
+        $visibility = !empty($_SESSION['visibility']) ? $_SESSION['visibility'] : '';
        $this->tpl->assign('visibility', $visibility);
        $this->tpl->assign('untaggedonly', !empty($_SESSION['untaggedonly']));
        $this->tpl->assign('pagetitle', $this->conf->get('general.title', 'Shaarli'));
@@ -105,6 +126,19 @@ class PageBuilder
        if ($this->linkDB !== null) {
            $this->tpl->assign('tags', $this->linkDB->linksCountPerTag());
        }
+        $this->tpl->assign(
+            'thumbnails_enabled',
+            $this->conf->get('thumbnails.mode', Thumbnailer::MODE_NONE) !== Thumbnailer::MODE_NONE
+        );
+        $this->tpl->assign('thumbnails_width', $this->conf->get('thumbnails.width'));
+        $this->tpl->assign('thumbnails_height', $this->conf->get('thumbnails.height'));
+        if (!empty($_SESSION['warnings'])) {
+            $this->tpl->assign('global_warnings', $_SESSION['warnings']);
+            unset($_SESSION['warnings']);
+        }
        // To be removed with a proper theme configuration.
        $this->tpl->assign('conf', $this->conf);
    }
@@ -136,7 +170,7 @@ class PageBuilder
            $this->initialize();
        }
-        if (empty($data) || !is_array($data)){
+        if (empty($data) || !is_array($data)) {
            return false;
        }
@@ -163,16 +197,16 @@ class PageBuilder
    /**
     * Render a 404 page (uses the template : tpl/404.tpl)
-     * usage : $PAGE->render404('The link was deleted')
+     * usage: $PAGE->render404('The link was deleted')
     *
-     * @param string $message A messate to display what is not found
+     * @param string $message A message to display what is not found
     */
    public function render404($message = '')
    {
        if (empty($message)) {
            $message = t('The page you are trying to reach does not exist or has been deleted.');
        }
-        header($_SERVER['SERVER_PROTOCOL'] .' '. t('404 Not Found'));
+        header($_SERVER['SERVER_PROTOCOL'] . ' ' . t('404 Not Found'));
        $this->tpl->assign('error_message', $message);
        $this->renderPage('404');
    }
diff --git a/application/ThemeUtils.php b/application/render/ThemeUtils.php
index 16f2f6a2..86096c64 100644
--- a/application/ThemeUtils.php
+++ b/application/render/ThemeUtils.php
@@ -1,6 +1,6 @@
 <?php
-namespace Shaarli;
+namespace Shaarli\Render;
 /**
 * Class ThemeUtils
diff --git a/application/security/LoginManager.php b/application/security/LoginManager.php
index 5a58926d..1ff3d0be 100644
--- a/application/security/LoginManager.php
+++ b/application/security/LoginManager.php
@@ -98,7 +98,6 @@ class LoginManager
            // The user client has a valid stay-signed-in cookie
            // Session information is updated with the current client information
            $this->sessionManager->storeLoginInfo($clientIpId);
        } elseif ($this->sessionManager->hasSessionExpired()
            || $this->sessionManager->hasClientIpChanged($clientIpId)
        ) {
diff --git a/application/Updater.php b/application/updater/Updater.php
index dece2c02..f12e3516 100644
--- a/application/Updater.php
+++ b/application/updater/Updater.php
@@ -1,10 +1,24 @@
 <?php
+namespace Shaarli\Updater;
+use Exception;
+use RainTPL;
+use ReflectionClass;
+use ReflectionException;
+use ReflectionMethod;
+use Shaarli\ApplicationUtils;
+use Shaarli\Bookmark\LinkDB;
+use Shaarli\Bookmark\LinkFilter;
 use Shaarli\Config\ConfigJson;
-use Shaarli\Config\ConfigPhp;
 use Shaarli\Config\ConfigManager;
+use Shaarli\Config\ConfigPhp;
+use Shaarli\Exceptions\IOException;
+use Shaarli\Thumbnailer;
+use Shaarli\Updater\Exception\UpdaterException;
 /**
- * Class Updater.
+ * Class updater.
 * Used to update stuff when a new Shaarli's version is reached.
 * Update methods are ran only once, and the stored in a JSON file.
 */
@@ -31,6 +45,11 @@ class Updater
    protected $isLoggedIn;
    /**
+     * @var array $_SESSION
+     */
+    protected $session;
+    /**
     * @var ReflectionMethod[] List of current class methods.
     */
    protected $methods;
@@ -42,13 +61,17 @@ class Updater
     * @param LinkDB        $linkDB      LinkDB instance.
     * @param ConfigManager $conf        Configuration Manager instance.
     * @param boolean       $isLoggedIn  True if the user is logged in.
+     * @param array         $session     $_SESSION (by reference)
+     *
+     * @throws ReflectionException
     */
-    public function __construct($doneUpdates, $linkDB, $conf, $isLoggedIn)
+    public function __construct($doneUpdates, $linkDB, $conf, $isLoggedIn, &$session = [])
    {
        $this->doneUpdates = $doneUpdates;
        $this->linkDB = $linkDB;
        $this->conf = $conf;
        $this->isLoggedIn = $isLoggedIn;
+        $this->session = &$session;
        // Retrieve all update methods.
        $class = new ReflectionClass($this);
@@ -73,12 +96,12 @@ class Updater
        }
        if ($this->methods === null) {
-            throw new UpdaterException(t('Couldn\'t retrieve Updater class methods.'));
+            throw new UpdaterException(t('Couldn\'t retrieve updater class methods.'));
        }
        foreach ($this->methods as $method) {
            // Not an update method or already done, pass.
-            if (! startsWith($method->getName(), 'updateMethod')
+            if (!startsWith($method->getName(), 'updateMethod')
                || in_array($method->getName(), $this->doneUpdates)
            ) {
                continue;
@@ -129,7 +152,7 @@ class Updater
                }
            }
            $this->conf->write($this->isLoggedIn);
-            unlink($this->conf->get('resource.data_dir').'/options.php');
+            unlink($this->conf->get('resource.data_dir') . '/options.php');
        }
        return true;
@@ -164,16 +187,16 @@ class Updater
        $subConfig = array('config', 'plugins');
        foreach ($subConfig as $sub) {
            foreach ($oldConfig[$sub] as $key => $value) {
-                if (isset($legacyMap[$sub .'.'. $key])) {
+                if (isset($legacyMap[$sub . '.' . $key])) {
-                    $configKey = $legacyMap[$sub .'.'. $key];
+                    $configKey = $legacyMap[$sub . '.' . $key];
                } else {
-                    $configKey = $sub .'.'. $key;
+                    $configKey = $sub . '.' . $key;
                }
                $this->conf->set($configKey, $value);
            }
        }
-        try{
+        try {
            $this->conf->write($this->isLoggedIn);
            return true;
        } catch (IOException $e) {
@@ -223,7 +246,7 @@ class Updater
            return true;
        }
-        $save = $this->conf->get('resource.data_dir') .'/datastore.'. date('YmdHis') .'.php';
+        $save = $this->conf->get('resource.data_dir') . '/datastore.' . date('YmdHis') . '.php';
        copy($this->conf->get('resource.datastore'), $save);
        $links = array();
@@ -297,7 +320,7 @@ class Updater
        // We run the update only if this folder still contains the template files.
        $tplDir = $this->conf->get('resource.raintpl_tpl');
        $tplFile = $tplDir . '/linklist.html';
-        if (! file_exists($tplFile)) {
+        if (!file_exists($tplFile)) {
            return true;
        }
@@ -321,7 +344,7 @@ class Updater
     */
    public function updateMethodMoveUserCss()
    {
-        if (! is_file('inc/user.css')) {
+        if (!is_file('inc/user.css')) {
            return true;
        }
@@ -357,11 +380,11 @@ class Updater
     */
    public function updateMethodPiwikUrl()
    {
-        if (! $this->conf->exists('plugins.PIWIK_URL') || startsWith($this->conf->get('plugins.PIWIK_URL'), 'http')) {
+        if (!$this->conf->exists('plugins.PIWIK_URL') || startsWith($this->conf->get('plugins.PIWIK_URL'), 'http')) {
            return true;
        }
-        $this->conf->set('plugins.PIWIK_URL', 'http://'. $this->conf->get('plugins.PIWIK_URL'));
+        $this->conf->set('plugins.PIWIK_URL', 'http://' . $this->conf->get('plugins.PIWIK_URL'));
        $this->conf->write($this->isLoggedIn);
        return true;
@@ -471,109 +494,60 @@ class Updater
            return true;
        }
-        if (! $this->conf->exists('general.download_max_size')) {
+        if (!$this->conf->exists('general.download_max_size')) {
-            $this->conf->set('general.download_max_size', 1024*1024*4);
+            $this->conf->set('general.download_max_size', 1024 * 1024 * 4);
        }
-        if (! $this->conf->exists('general.download_timeout')) {
+        if (!$this->conf->exists('general.download_timeout')) {
            $this->conf->set('general.download_timeout', 30);
        }
        $this->conf->write($this->isLoggedIn);
        return true;
    }
-}
-/**
- * Class UpdaterException.
- */
-class UpdaterException extends Exception
-{
-    /**
-     * @var string Method where the error occurred.
-     */
-    protected $method;
-    /**
-     * @var Exception The parent exception.
-     */
-    protected $previous;
-    /**
-     * Constructor.
-     *
-     * @param string         $message  Force the error message if set.
-     * @param string         $method   Method where the error occurred.
-     * @param Exception|bool $previous Parent exception.
-     */
-    public function __construct($message = '', $method = '', $previous = false)
-    {
-        $this->method = $method;
-        $this->previous = $previous;
-        $this->message = $this->buildMessage($message);
-    }
    /**
-     * Build the exception error message.
+     * * Move thumbnails management to WebThumbnailer, coming with new settings.
-     *
-     * @param string $message Optional given error message.
-     *
-     * @return string The built error message.
     */
-    private function buildMessage($message)
+    public function updateMethodWebThumbnailer()
    {
-        $out = '';
+        if ($this->conf->exists('thumbnails.mode')) {
-        if (! empty($message)) {
+            return true;
-            $out .= $message . PHP_EOL;
        }
-        if (! empty($this->method)) {
+        $thumbnailsEnabled = extension_loaded('gd') && $this->conf->get('thumbnail.enable_thumbnails', true);
-            $out .= t('An error occurred while running the update ') . $this->method . PHP_EOL;
+        $this->conf->set('thumbnails.mode', $thumbnailsEnabled ? Thumbnailer::MODE_ALL : Thumbnailer::MODE_NONE);
-        }
+        $this->conf->set('thumbnails.width', 125);
+        $this->conf->set('thumbnails.height', 90);
+        $this->conf->remove('thumbnail');
+        $this->conf->write(true);
-        if (! empty($this->previous)) {
+        if ($thumbnailsEnabled) {
-            $out .= '  '. $this->previous->getMessage();
+            $this->session['warnings'][] = t(
+                'You have enabled or changed thumbnails mode. <a href="?do=thumbs_update">Please synchronize them</a>.'
+            );
        }
-        return $out;
+        return true;
    }
-}
-/**
+    /**
- * Read the updates file, and return already done updates.
+     * Set sticky = false on all links
- *
+     *
- * @param string $updatesFilepath Updates file path.
+     * @return bool true if the update is successful, false otherwise.
- *
+     */
- * @return array Already done update methods.
+    public function updateMethodSetSticky()
- */
+    {
-function read_updates_file($updatesFilepath)
+        foreach ($this->linkDB as $key => $link) {
-{
+            if (isset($link['sticky'])) {
-    if (! empty($updatesFilepath) && is_file($updatesFilepath)) {
+                return true;
-        $content = file_get_contents($updatesFilepath);
+            }
-        if (! empty($content)) {
+            $link['sticky'] = false;
-            return explode(';', $content);
+            $this->linkDB[$key] = $link;
        }
-    }
-    return array();
-}
-/**
+        $this->linkDB->save($this->conf->get('resource.page_cache'));
- * Write updates file.
- *
- * @param string $updatesFilepath Updates file path.
- * @param array  $updates         Updates array to write.
- *
- * @throws Exception Couldn't write version number.
- */
-function write_updates_file($updatesFilepath, $updates)
-{
-    if (empty($updatesFilepath)) {
-        throw new Exception(t('Updates file path is not set, can\'t write updates.'));
-    }
-    $res = file_put_contents($updatesFilepath, implode(';', $updates));
+        return true;
-    if ($res === false) {
-        throw new Exception(t('Unable to write updates in '. $updatesFilepath . '.'));
    }
 }
diff --git a/application/updater/UpdaterUtils.php b/application/updater/UpdaterUtils.php
new file mode 100644
index 00000000..34d4f422
--- /dev/null
+++ b/application/updater/UpdaterUtils.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * Read the updates file, and return already done updates.
+ *
+ * @param string $updatesFilepath Updates file path.
+ *
+ * @return array Already done update methods.
+ */
+function read_updates_file($updatesFilepath)
+{
+    if (! empty($updatesFilepath) && is_file($updatesFilepath)) {
+        $content = file_get_contents($updatesFilepath);
+        if (! empty($content)) {
+            return explode(';', $content);
+        }
+    }
+    return array();
+}
+/**
+ * Write updates file.
+ *
+ * @param string $updatesFilepath Updates file path.
+ * @param array  $updates         Updates array to write.
+ *
+ * @throws Exception Couldn't write version number.
+ */
+function write_updates_file($updatesFilepath, $updates)
+{
+    if (empty($updatesFilepath)) {
+        throw new Exception(t('Updates file path is not set, can\'t write updates.'));
+    }
+    $res = file_put_contents($updatesFilepath, implode(';', $updates));
+    if ($res === false) {
+        throw new Exception(t('Unable to write updates in '. $updatesFilepath . '.'));
+    }
+}
diff --git a/application/updater/exception/UpdaterException.php b/application/updater/exception/UpdaterException.php
new file mode 100644
index 00000000..20aceccf
--- /dev/null
+++ b/application/updater/exception/UpdaterException.php
@@ -0,0 +1,60 @@
+<?php
+namespace Shaarli\Updater\Exception;
+use Exception;
+/**
+ * Class UpdaterException.
+ */
+class UpdaterException extends Exception
+{
+    /**
+     * @var string Method where the error occurred.
+     */
+    protected $method;
+    /**
+     * @var Exception The parent exception.
+     */
+    protected $previous;
+    /**
+     * Constructor.
+     *
+     * @param string         $message  Force the error message if set.
+     * @param string         $method   Method where the error occurred.
+     * @param Exception|bool $previous Parent exception.
+     */
+    public function __construct($message = '', $method = '', $previous = false)
+    {
+        $this->method = $method;
+        $this->previous = $previous;
+        $this->message = $this->buildMessage($message);
+    }
+    /**
+     * Build the exception error message.
+     *
+     * @param string $message Optional given error message.
+     *
+     * @return string The built error message.
+     */
+    private function buildMessage($message)
+    {
+        $out = '';
+        if (!empty($message)) {
+            $out .= $message . PHP_EOL;
+        }
+        if (!empty($this->method)) {
+            $out .= t('An error occurred while running the update ') . $this->method . PHP_EOL;
+        }
+        if (!empty($this->previous)) {
+            $out .= '  ' . $this->previous->getMessage();
+        }
+        return $out;
+    }
+}