diff --git a/API/examples/PHP/ClickMeetingRestClient.php b/API/examples/PHP/ClickMeetingRestClient.php
index 744cd4c..6343ed3 100644
--- a/API/examples/PHP/ClickMeetingRestClient.php
+++ b/API/examples/PHP/ClickMeetingRestClient.php
@@ -1,7 +1,9 @@
 <?php
 
+use \Exception;
+
 /**
- * ClickMeeting REST client
+ * Class ClickMeetingRestClient
  */
 class ClickMeetingRestClient
 {
@@ -25,12 +27,14 @@ class ClickMeetingRestClient
 
     /**
      * Curl options
-     * @var options
+     * @var array
      */
-    protected $curl_options = array(
+    protected $curl_options = [
+        CURLOPT_ENCODING => 'gzip,deflate',
+        CURLOPT_RETURNTRANSFER => 1,
         CURLOPT_CONNECTTIMEOUT => 8,
         CURLOPT_TIMEOUT => 8
-    );
+    ];
 
     /**
      * Error codes
@@ -49,7 +53,7 @@ class ClickMeetingRestClient
 
     /**
      * Allowed formats
-     * @var unknown
+     * @var array
      */
     protected $formats = array('json', 'xml', 'js', 'printr');
 
@@ -58,10 +62,9 @@ class ClickMeetingRestClient
      * @param array $params
      * @throws Exception
      */
-    public function __construct(array $params)
+    public function __construct(array $params = null)
     {
-        if (false === extension_loaded('curl'))
-        {
+        if (false === extension_loaded('curl')) {
             throw new Exception('The curl extension must be loaded for using this class!');
         }
 
@@ -70,16 +73,16 @@ public function __construct(array $params)
         $this->format = isset($params['format']) && in_array(strtolower($params['format']), $this->formats) ? strtolower($params['format']) : $this->format;
     }
 
-
     /**
      * Get response
+     *
      * @param string $method
      * @param string $path
      * @param array $params
      * @param bool $format_response
      * @param bool $is_upload_file
-     * @throws Exception
      * @return string|array
+     * @throws Exception
      */
     protected function sendRequest($method, $path, $params = null, $format_response = true, $is_upload_file = false)
     {
@@ -87,13 +90,13 @@ protected function sendRequest($method, $path, $params = null, $format_response
         $curl = curl_init();
 
         // set URL
-        curl_setopt($curl, CURLOPT_URL, $this->url.$path.'.'.(isset($this->format) ? $this->format : 'json'));
+        curl_setopt($curl, CURLOPT_URL, $this->url . $path . '.' . (isset($this->format) ? $this->format : 'json'));
+
         // set api key
-        $headers = array( 'X-Api-Key:' . $this->api_key);
+        $headers = array('X-Api-Key:' . $this->api_key);
 
         // is uplaoded file
-        if (true == $is_upload_file)
-        {
+        if (true == $is_upload_file) {
             $headers[] = 'Content-type: multipart/form-data';
         }
 
@@ -106,8 +109,7 @@ protected function sendRequest($method, $path, $params = null, $format_response
                 $headers[] = 'Expect:';
                 break;
             case 'PUT':
-                if(empty($params))
-                {
+                if (empty($params)) {
                     $headers[] = 'Content-Length: 0';
                 }
                 curl_setopt($curl, CURLOPT_CUSTOMREQUEST, $method);
@@ -119,13 +121,10 @@ protected function sendRequest($method, $path, $params = null, $format_response
         curl_setopt($curl, CURLOPT_HTTPHEADER, $headers);
 
         // add params
-        if (!empty($params))
-        {
+        if (!empty($params)) {
             curl_setopt($curl, CURLOPT_POSTFIELDS, $is_upload_file ? $params : http_build_query($params));
         }
 
-        curl_setopt($curl, CURLOPT_ENCODING, 'gzip,deflate');
-        curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
         curl_setopt_array($curl, $this->curl_options);
 
         // send the request
@@ -133,54 +132,59 @@ protected function sendRequest($method, $path, $params = null, $format_response
 
         $http_code = curl_getinfo($curl, CURLINFO_HTTP_CODE);
 
-        if (isset($this->http_errors[$http_code]))
-        {
+        if (isset($this->http_errors[$http_code])) {
             throw new Exception($response, $http_code);
-        }
-        elseif (!in_array($http_code, array(200,201)))
-        {
+        } elseif (!in_array($http_code, array(200, 201))) {
             throw new Exception('Response status code: ' . $http_code);
         }
 
         // check for curl error
-        if (0 < curl_errno($curl))
-        {
-            throw new Exception('Unable to connect to '.$this->url . ' Error: ' . curl_error($curl));
+        if (0 < curl_errno($curl)) {
+            throw new Exception('Unable to connect to ' . $this->url . ' Error: ' . curl_error($curl));
         }
 
         // close the connection
         curl_close($curl);
 
         // check return format
-        if (!isset($this->format) && true == $format_response)
-        {
+        if (!isset($this->format) && true == $format_response) {
             $response = json_decode($response);
         }
+
         return $response;
     }
 
     /**
      * Get conferences
+     *
      * @param string $status
      * @param int $page
+     * @return mixed
+     * @throws Exception
      */
     public function conferences($status = 'active', $page = 1)
     {
-        return $this->sendRequest('GET', 'conferences/'.$status . '?page=' . $page);
+        return $this->sendRequest('GET', 'conferences/' . $status . '?page=' . $page);
     }
 
     /**
      * Get conference
-     * @param unknown $room_id
+     *
+     * @param string $room_id
+     * @return mixed
+     * @throws Exception
      */
     public function conference($room_id)
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id);
+        return $this->sendRequest('GET', 'conferences/' . $room_id);
     }
 
     /**
      * Add conference
+     *
      * @param array $params
+     * @return mixed
+     * @throws Exception
      */
     public function addConference(array $params)
     {
@@ -189,51 +193,61 @@ public function addConference(array $params)
 
     /**
      * Edit conference
+     *
      * @param int $room_id
      * @param array $params
+     * @return mixed
+     * @throws Exception
      */
     public function editConference($room_id, array $params)
     {
-        return $this->sendRequest('PUT', 'conferences/'.$room_id, $params);
+        return $this->sendRequest('PUT', 'conferences/' . $room_id, $params);
     }
 
     /**
      * Delete conference
+     *
      * @param int $room_id
+     * @return mixed
+     * @throws Exception
      */
     public function deleteConference($room_id)
     {
-        return $this->sendRequest('DELETE', 'conferences/'.$room_id);
+        return $this->sendRequest('DELETE', 'conferences/' . $room_id);
     }
 
     /**
      * Conference autologin hash
-     * @param unknown $room_id
+     *
+     * @param string $room_id
      * @param array $params
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceAutologinHash($room_id, array $params)
     {
-        return $this->sendRequest('POST', 'conferences/'.$room_id.'/room/autologin_hash', $params);
+        return $this->sendRequest('POST', 'conferences/' . $room_id . '/room/autologin_hash', $params);
     }
 
     /**
      * Send invitation mail
+     *
      * @param int $room_id
      * @param string $lang
      * @param array $params
-     * @return Ambigous <string, multitype:, mixed>
+     * @return mixed
+     * @throws Exception
      */
-    public function sendConferenceEmailInvitations($room_id, $lang = 'en', $params)
+    public function sendConferenceEmailInvitations($room_id, $params, $lang = 'en')
     {
-        return $this->sendRequest('POST', 'conferences/'.$room_id.'/invitation/email/'.$lang, $params);
+        return $this->sendRequest('POST', 'conferences/' . $room_id . '/invitation/email/' . $lang, $params);
     }
 
     /**
      * Conference skins
-     * @param int $room_id
-     * @param string $lang
-     * @param array $params
-     * @return Ambigous <string, multitype:, mixed>
+     *
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceSkins()
     {
@@ -242,66 +256,87 @@ public function conferenceSkins()
 
     /**
      * Conference generate tokens
+     *
      * @param int $room_id
      * @param array $params
+     * @return mixed
+     * @throws Exception
      */
     public function generateConferenceTokens($room_id, array $params)
     {
-        return $this->sendRequest('POST', 'conferences/'.$room_id.'/tokens', $params);
+        return $this->sendRequest('POST', 'conferences/' . $room_id . '/tokens', $params);
     }
 
     /**
      * Get coference tokens
+     *
      * @param int $room_id
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceTokens($room_id)
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id.'/tokens');
+        return $this->sendRequest('GET', 'conferences/' . $room_id . '/tokens');
     }
 
     /**
      * Get conference sessions
-     * @param unknown $room_id
+     *
+     * @param string $room_id
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceSessions($room_id)
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id.'/sessions');
+        return $this->sendRequest('GET', 'conferences/' . $room_id . '/sessions');
     }
 
     /**
      * Get conference session
+     *
      * @param int $room_id
      * @param int $session_id
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceSession($room_id, $session_id)
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id.'/sessions/'.$session_id);
+        return $this->sendRequest('GET', 'conferences/' . $room_id . '/sessions/' . $session_id);
     }
 
     /**
      * Get conference session attendees
+     *
      * @param int $room_id
      * @param int $session_id
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceSessionAttendees($room_id, $session_id)
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id.'/sessions/'.$session_id.'/attendees');
+        return $this->sendRequest('GET', 'conferences/' . $room_id . '/sessions/' . $session_id . '/attendees');
     }
 
     /**
      * Generate pdf report
+     *
      * @param int $room_id
      * @param int $session_id
      * @param string $lang
+     * @return mixed
+     * @throws Exception
      */
     public function generateConferenceSessionPDF($room_id, $session_id, $lang = 'en')
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id.'/sessions/'.$session_id.'/generate-pdf/'.$lang);
+        return $this->sendRequest('GET', 'conferences/' . $room_id . '/sessions/' . $session_id . '/generate-pdf/' . $lang);
     }
 
     /**
      * Add new contact
+     *
      * @param array $params
+     * @return mixed
+     * @throws Exception
      */
     public function addContact($params)
     {
@@ -310,6 +345,9 @@ public function addContact($params)
 
     /**
      * Get timezone list
+     *
+     * @return mixed
+     * @throws Exception
      */
     public function timeZoneList()
     {
@@ -318,15 +356,21 @@ public function timeZoneList()
 
     /**
      * Get timezone by country
+     *
      * @param string $country
+     * @return mixed
+     * @throws Exception
      */
     public function countryTimeZoneList($country)
     {
-        return $this->sendRequest('GET', 'time_zone_list/'.$country);
+        return $this->sendRequest('GET', 'time_zone_list/' . $country);
     }
 
     /**
      * Get phone gateways
+     *
+     * @return mixed
+     * @throws Exception
      */
     public function phoneGatewayList()
     {
@@ -335,37 +379,49 @@ public function phoneGatewayList()
 
     /**
      * Add conference registration
+     *
      * @param int $room_id
      * @param array $params
+     * @return mixed
+     * @throws Exception
      */
     public function addConferenceRegistration($room_id, $params)
     {
-        return $this->sendRequest('POST', 'conferences/'.$room_id.'/registration', $params);
+        return $this->sendRequest('POST', 'conferences/' . $room_id . '/registration', $params);
     }
 
     /**
      * Get conference registrants
+     *
      * @param int $room_id
      * @param string $status
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceRegistrations($room_id, $status)
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id.'/registrations/'.$status);
+        return $this->sendRequest('GET', 'conferences/' . $room_id . '/registrations/' . $status);
     }
 
     /**
-     * Get conference session registants
+     * Get conference session registrants
+     *
      * @param int $room_id
      * @param int $session_id
      * @param string $status
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceSessionRegistrations($room_id, $session_id, $status)
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id.'/sessions'.$session_id.'/registrations/'.$status);
+        return $this->sendRequest('GET', 'conferences/' . $room_id . '/sessions' . $session_id . '/registrations/' . $status);
     }
 
     /**
      * Get files from library
+     *
+     * @return mixed
+     * @throws Exception
      */
     public function fileLibrary()
     {
@@ -373,80 +429,107 @@ public function fileLibrary()
     }
 
     /**
-     * Get coference file library
+     * Get conference file library
+     *
      * @param int $room_id
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceFileLibrary($room_id)
     {
-        return $this->sendRequest('GET', 'file-library/conferences/'.$room_id);
+        return $this->sendRequest('GET', 'file-library/conferences/' . $room_id);
     }
 
     /**
      * Get file details
+     *
      * @param int $file_id
+     * @return mixed
+     * @throws Exception
      */
     public function fileLibraryFile($file_id)
     {
-        return $this->sendRequest('GET', 'file-library/'.$file_id);
+        return $this->sendRequest('GET', 'file-library/' . $file_id);
     }
 
     /**
      * Add file to library
+     *
      * @param string $file_path
+     * @return mixed
+     * @throws Exception
      */
     public function addFileLibraryFile($file_path)
     {
-        return $this->sendRequest('POST', 'file-library', array('uploaded' => '@'.$file_path), true, true);
+        return $this->sendRequest('POST', 'file-library', array('uploaded' => '@' . $file_path), true, true);
     }
 
     /**
      * Download file
+     *
      * @param int $file_id
+     * @return mixed
+     * @throws Exception
      */
     public function fileLibraryContent($file_id)
     {
-        return $this->sendRequest('GET', 'file-library/'.$file_id.'/download', null, false);
+        return $this->sendRequest('GET', 'file-library/' . $file_id . '/download', null, false);
     }
 
     /**
      * Delete file
+     *
      * @param int $file_id
+     * @return mixed
+     * @throws Exception
      */
     public function deleteFileLibraryFile($file_id)
     {
-        return $this->sendRequest('DELETE', 'file-library/'.$file_id);
+        return $this->sendRequest('DELETE', 'file-library/' . $file_id);
     }
 
     /**
      * Get conference recordings
+     *
      * @param int $room_id
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceRecordings($room_id)
     {
-        return $this->sendRequest('GET', 'conferences/'.$room_id.'/recordings');
+        return $this->sendRequest('GET', 'conferences/' . $room_id . '/recordings');
     }
 
     /**
      * Delete conference recordings
+     *
      * @param int $room_id
+     * @return mixed
+     * @throws Exception
      */
     public function deleteConferenceRecordings($room_id)
     {
-        return $this->sendRequest('DELETE', 'conferences/'.$room_id.'/recordings');
+        return $this->sendRequest('DELETE', 'conferences/' . $room_id . '/recordings');
     }
 
     /**
      * Delete conference recording
+     *
      * @param int $room_id
      * @param int $recording_id
+     * @return mixed
+     * @throws Exception
      */
     public function deleteConferenceRecording($room_id, $recording_id)
     {
-        return $this->sendRequest('DELETE', 'conferences/'.$room_id.'/recordings/'.$recording_id);
+        return $this->sendRequest('DELETE', 'conferences/' . $room_id . '/recordings/' . $recording_id);
     }
 
     /**
      * Get chats
+     *
+     * @return mixed
+     * @throws Exception
      */
     public function chats()
     {
@@ -455,10 +538,13 @@ public function chats()
 
     /**
      * Get chat record
+     *
      * @param int $session_id
+     * @return mixed
+     * @throws Exception
      */
     public function conferenceSessionChats($session_id)
     {
-        return $this->sendRequest('GET', 'chats/'.$session_id, null, false);
+        return $this->sendRequest('GET', 'chats/' . $session_id, null, false);
     }
-}
+}
\ No newline at end of file