CI framework Session.php source code analysis, ci framework session.php_PHP tutorial

CI framework Session.php source code analysis, ci framework session.php

CI's Session is not a native session, it is exactly all the cookie based sessions I have previously used. In addition, CI can configure whether to store the session in the database according to the user's choice. I like this function very much, and there is also the "flash-out" Data" function, the flashed data is only available for the next server request, and will be automatically cleared afterwards. Common usage methods are:

$this->session->set_userdata('some_name', 'some_value'); //Set session data

$this->session->userdata('item'); //Get session data

$this->session->unset_userdata('some_name'); //Delete session data

$this->session->sess_destroy(); //Destroy session data

$this->session->set_flashdata('item', 'value'); //Set flash data

$this->session->flashdata('item'); //Get flash data

$this->session->keep_flashdata('item'); //Keep flash data

Copy code The code is as follows:

/**
 * CI是 session based cookie
 */
class CI_Session {
var $sess_encrypt_cookie = FALSE; //Whether to encrypt the session
var $sess_use_database = FALSE; //Whether to store the session in the database
var $sess_table_name = ''; //The table name where the session stores data
var $sess_expiration = 7200; //session expiration time
var $sess_expire_on_close = FALSE; //Whether to automatically expire the session when the browser window is closed
var $sess_match_ip = FALSE;//Whether to read session data through the user’s IP address
var $sess_match_useragent = TRUE; //Whether to read session data according to the corresponding User Agent.
var $sess_cookie_name = 'ci_session'; //cookie name
var $cookie_prefix = ''; //cookie prefix
var $cookie_path = ''; //cookie path
var $cookie_domain = ''; //cookie scope
var $cookie_secure = FALSE; //Whether it is valid under the secure https protocol
var $sess_time_to_update = 300; //How often the session cookie is updated
var $encryption_key = ''; //Encryption key
var $flashdata_key = 'flash';
var $time_reference = 'time';
var $gc_probability = 5; //Ability to recycle session
var $userdata = array(); //User session data storage variable
var $CI; //CI super handle
var $now; //Current time
public function __construct($params = array())
{
log_message('debug', "Session Class Initialized");
// Get CI super class
$this->CI =& get_instance();
// Get the configuration data in the config file
foreach (array('sess_encrypt_cookie', 'sess_use_database', 'sess_table_name', 'sess_expiration', 'sess_expire_on_close', 'sess_match_ip', 'sess_match_useragent', 'sess_cookie_name', 'cookie_path', 'cookie_domain', 'cookie_secure', 'sess_time_to_update ', 'time_reference', 'cookie_prefix', 'encryption_key') as $key)
{
$this->$key = (isset($params[$key])) ? $params[$key] : $this->CI->config->item($key);
}
//Encryption_key
must be set if ($this->encryption_key == '')
{
Show_error('In order to use the Session class you are required to set an encryption key in your config file.');
}
//Load string helper function
$this->CI->load->helper('string');
// DIf the cookie is encrypted, introduce the encryption class
if ($this->sess_encrypt_cookie == TRUE)
{
$this->CI->load->library('encrypt');
}
// If the session is included in the database, introduce db
if ($this->sess_use_database === TRUE AND $this->sess_table_name != '')
{
$this->CI->load->database();
}
// Get the current time
$this->now = $this->_get_time();
// If the session validity time is not set, the default is two years
if ($this->sess_expiration == 0)
{
$this->sess_expiration = (60*60*24*365*2);
}
// Get cookie name
$this->sess_cookie_name = $this->cookie_prefix.$this->sess_cookie_name;
// If the session does not exist, create a new session
if ( ! $this->sess_read())
{
$this->sess_create();
}
else
{
$this->sess_update();
}
// Flash out the flash data marked old
$this->_flashdata_sweep();
                             // Mark the new pop-up data as old. The data marked as old will flash out at the next request
$this->_flashdata_mark();
//Recycle/delete expired session
$this->_sess_gc();
  log_message('debug', "Session routines successfully run");
 }
 // --------------------------------------------------------------------
 /**
* Read session data
​*/
 function sess_read()
 {
  // 获取session
  $session = $this->CI->input->cookie($this->sess_cookie_name);
  // 没有session  拜拜
  if ($session === FALSE)
  {
   log_message('debug', 'A session cookie was not found.');
   return FALSE;
  }
  // 如果加密了cookie
  if ($this->sess_encrypt_cookie == TRUE)
  {
   $session = $this->CI->encrypt->decode($session);
  }
  else
  {
   // encryption was not used, so we need to check the md5 hash
   $hash  = substr($session, strlen($session)-32); // get last 32 chars
   $session = substr($session, 0, strlen($session)-32);
   // Does the md5 hash match?  This is to prevent manipulation of session data in userspace
   if ($hash !==  md5($session.$this->encryption_key))
   {
    log_message('error', 'The session cookie data did not match what was expected. This could be a possible hacking attempt.');
    $this->sess_destroy();
    return FALSE;
   }
  }
  // 反序列化存入cookie的session数组
  $session = $this->_unserialize($session);
  // 检测session的数据
  if ( ! is_array($session) OR ! isset($session['session_id']) OR ! isset($session['ip_address']) OR ! isset($session['user_agent']) OR ! isset($session['last_activity']))
  {
   $this->sess_destroy();
   return FALSE;
  }
  // session数据过期了吗
  if (($session['last_activity'] + $this->sess_expiration) < $this->now)
  {
   $this->sess_destroy();
   return FALSE;
  }
  // 是否是根据用户ip来读取session数据
  if ($this->sess_match_ip == TRUE AND $session['ip_address'] != $this->CI->input->ip_address())
  {
   $this->sess_destroy();
   return FALSE;
  }
  // 是否根据ua来匹配session数据
  if ($this->sess_match_useragent == TRUE AND trim($session['user_agent']) != trim(substr($this->CI->input->user_agent(), 0, 120)))
  {
   $this->sess_destroy();
   return FALSE;
  }
  // 如果session入库了，这种方式应该更安全点，当然负载大时，就不建议了，数据库读写压力大
  if ($this->sess_use_database === TRUE)
  {
   $this->CI->db->where('session_id', $session['session_id']);
   if ($this->sess_match_ip == TRUE)
   {
    $this->CI->db->where('ip_address', $session['ip_address']);
   }
   if ($this->sess_match_useragent == TRUE)
   {
    $this->CI->db->where('user_agent', $session['user_agent']);
   }
   $query = $this->CI->db->get($this->sess_table_name);
   // No result?  Kill it!
   if ($query->num_rows() == 0)
   {
    $this->sess_destroy();
    return FALSE;
   }
   // Is there custom data?  If so, add it to the main session array
   $row = $query->row();
   if (isset($row->user_data) AND $row->user_data != '')
   {
    $custom_data = $this->_unserialize($row->user_data);
    if (is_array($custom_data))
    {
     foreach ($custom_data as $key => $val)
     {
      $session[$key] = $val;
     }
    }
   }
  }
  // Session is valid!
  $this->userdata = $session;
  unset($session);
  return TRUE;
 }
 // --------------------------------------------------------------------
 /**
* Write the read session data into
​*/
 function sess_write()
 {
  // 是否写入db
  if ($this->sess_use_database === FALSE)
  {
   $this->_set_cookie();
   return;
  }
  // set the custom userdata, the session data we will set in a second
  $custom_userdata = $this->userdata;
  $cookie_userdata = array();
  // Before continuing, we need to determine if there is any custom data to deal with.
  // Let's determine this by removing the default indexes to see if there's anything left in the array
  // and set the session data while we're at it
  foreach (array('session_id','ip_address','user_agent','last_activity') as $val)
  {
   unset($custom_userdata[$val]);
   $cookie_userdata[$val] = $this->userdata[$val];
  }
  // Did we find any custom data?  If not, we turn the empty array into a string
  // since there's no reason to serialize and store an empty array in the DB
  if (count($custom_userdata) === 0)
  {
   $custom_userdata = '';
  }
  else
  {
   // Serialize the custom data array so we can store it
   $custom_userdata = $this->_serialize($custom_userdata);
  }
  // 更新session记录
  $this->CI->db->where('session_id', $this->userdata['session_id']);
  $this->CI->db->update($this->sess_table_name, array('last_activity' => $this->userdata['last_activity'], 'user_data' => $custom_userdata));
  // Write the cookie.  Notice that we manually pass the cookie data array to the
  // _set_cookie() function. Normally that function will store $this->userdata, but
  // in this case that array contains custom data, which we do not want in the cookie.
  $this->_set_cookie($cookie_userdata);
 }
 // --------------------------------------------------------------------
 /**
* Create a new session
​*/
 function sess_create()
 {
                //保证sessid 安全唯一
  $sessid = '';
  while (strlen($sessid) < 32)
  {
   $sessid .= mt_rand(0, mt_getrandmax());
  }
  $sessid .= $this->CI->input->ip_address();
  $this->userdata = array(
       'session_id' => md5(uniqid($sessid, TRUE)),
       'ip_address' => $this->CI->input->ip_address(),
       'user_agent' => substr($this->CI->input->user_agent(), 0, 120),
       'last_activity' => $this->now,
       'user_data'  => ''
       );
  // Save the data to the DB if needed
  if ($this->sess_use_database === TRUE)
  {
   $this->CI->db->query($this->CI->db->insert_string($this->sess_table_name, $this->userdata));
  }
  // Write the cookie
  $this->_set_cookie();
 }
 // --------------------------------------------------------------------
 /**
* Update session
​*/
 function sess_update()
 {
  // 默认五分钟更新
  if (($this->userdata['last_activity'] + $this->sess_time_to_update) >= $this->now)
  {
   return;
  }
  // Save the old session id so we know which record to
  // update in the database if we need it
  $old_sessid = $this->userdata['session_id'];
  $new_sessid = '';
  while (strlen($new_sessid) < 32)
  {
   $new_sessid .= mt_rand(0, mt_getrandmax());
  }
  // To make the session ID even more secure we'll combine it with the user's IP
  $new_sessid .= $this->CI->input->ip_address();
  // Turn it into a hash
  $new_sessid = md5(uniqid($new_sessid, TRUE));
  // Update the session data in the session data array
  $this->userdata['session_id'] = $new_sessid;
  $this->userdata['last_activity'] = $this->now;
  // _set_cookie() will handle this for us if we aren't using database sessions
  // by pushing all userdata to the cookie.
  $cookie_data = NULL;
  // 更新数据库中几率
  if ($this->sess_use_database === TRUE)
  {
   // set cookie explicitly to only have our session data
   $cookie_data = array();
   foreach (array('session_id','ip_address','user_agent','last_activity') as $val)
   {
    $cookie_data[$val] = $this->userdata[$val];
   }
   $this->CI->db->query($this->CI->db->update_string($this->sess_table_name, array('last_activity' => $this->now, 'session_id' => $new_sessid), array('session_id' => $old_sessid)));
  }
  // 重新写入session
  $this->_set_cookie($cookie_data);
 }
 // --------------------------------------------------------------------
 /**
*Destroy all current session data
​*/
 function sess_destroy()
 {
  // Kill the session DB row
  if ($this->sess_use_database === TRUE && isset($this->userdata['session_id']))
  {
   $this->CI->db->where('session_id', $this->userdata['session_id']);
   $this->CI->db->delete($this->sess_table_name);
  }
  // Kill the cookie
  setcookie(
     $this->sess_cookie_name,
     addslashes(serialize(array())),
     ($this->now - 31500000),
     $this->cookie_path,
     $this->cookie_domain,
     0
    );
  // Kill session data
  $this->userdata = array();
 }
 // --------------------------------------------------------------------
 /**
* Get the value of the specified element in the session array
​*/
 function userdata($item)
 {
  return ( ! isset($this->userdata[$item])) ? FALSE : $this->userdata[$item];
 }
 // --------------------------------------------------------------------
 /**
* Get all session data
​*/
 function all_userdata()
 {
  return $this->userdata;
 }
 // --------------------------------------------------------------------
 /**
* Add and modify custom session data
​*/
 function set_userdata($newdata = array(), $newval = '')
 {
  if (is_string($newdata))
  {
   $newdata = array($newdata => $newval);
  }
                //支持数组组合方式
  if (count($newdata) > 0)
  {
   foreach ($newdata as $key => $val)
   {
    $this->userdata[$key] = $val;
   }
  }
  $this->sess_write();
 }
 // --------------------------------------------------------------------
 /**
* Delete elements in the session array,
​*/
 function unset_userdata($newdata = array())
 {
  if (is_string($newdata))
  {
   $newdata = array($newdata => '');
  }
  if (count($newdata) > 0)
  {
   foreach ($newdata as $key => $val)
   {
    unset($this->userdata[$key]);
   }
  }
  $this->sess_write();
 }
 // ------------------------------------------------------------------------
 /**
  * Add or change flashdata, only available
  * until the next request
  *
  * @access public
  * @param mixed
  * @param string
  * @return void
 */
 function set_flashdata($newdata = array(), $newval = '')
 {
  if (is_string($newdata))
  {
   $newdata = array($newdata => $newval);
  }
  if (count($newdata) > 0)
  {
   foreach ($newdata as $key => $val)
   {
    $flashdata_key = $this->flashdata_key.':new:'.$key;
    $this->set_userdata($flashdata_key, $val);
   }
  }
 }
 // ------------------------------------------------------------------------
 /**
* CI supports flashing data, which means that Session data is only available for the next server request. Sometimes if you still want the request after the next request to be valid. . .
* The keep_flashdata function is to continuously keep flash data so that it will be valid for the next request
​*/
 function keep_flashdata($key)
 {
                //将闪出数据标记成new
  $old_flashdata_key = $this->flashdata_key.':old:'.$key;
  $value = $this->userdata($old_flashdata_key);
  $new_flashdata_key = $this->flashdata_key.':new:'.$key;
  $this->set_userdata($new_flashdata_key, $value);
 }
 // ------------------------------------------------------------------------
 /**
* Get flash data
​*/
 function flashdata($key)
 {
  $flashdata_key = $this->flashdata_key.':old:'.$key;
  return $this->userdata($flashdata_key);
 }
 // ------------------------------------------------------------------------
 /**
* Mark the flash data as old so that _flashdata_sweep can clear the data
​*/
 function _flashdata_mark()
 {
  $userdata = $this->all_userdata();
  foreach ($userdata as $name => $value)
  {
   $parts = explode(':new:', $name);
   if (is_array($parts) && count($parts) === 2)
   {
    $new_name = $this->flashdata_key.':old:'.$parts[1];
    $this->set_userdata($new_name, $value);
    $this->unset_userdata($name);
   }
  }
 }
 // ------------------------------------------------------------------------
 /**
* Flash out the flash data marked as old
​*/
 function _flashdata_sweep()
 {
  $userdata = $this->all_userdata();
  foreach ($userdata as $key => $value)
  {
   if (strpos($key, ':old:'))
   {
    $this->unset_userdata($key);
   }
  }
 }
 //获取当前时间
 function _get_time()
 {
  if (strtolower($this->time_reference) == 'gmt')
  {
   $now = time();
   $time = mktime(gmdate("H", $now), gmdate("i", $now), gmdate("s", $now), gmdate("m", $now), gmdate("d", $now), gmdate("Y", $now));
  }
  else
  {
   $time = time();
  }
  return $time;
 }
 // --------------------------------------------------------------------
 /**
* Write session cookie
*
​*/
 function _set_cookie($cookie_data = NULL)
 {
  if (is_null($cookie_data))
  {
   $cookie_data = $this->userdata;
  }
  // 序列化数组
  $cookie_data = $this->_serialize($cookie_data);
                //加密数据
  if ($this->sess_encrypt_cookie == TRUE)
  {
   $cookie_data = $this->CI->encrypt->encode($cookie_data);
  }
  else
  {
   // if encryption is not used, we provide an md5 hash to prevent userside tampering
   $cookie_data = $cookie_data.md5($cookie_data.$this->encryption_key);
  }
                //sess_expire_on_close为TRUE则，浏览器关闭，session失效
  $expire = ($this->sess_expire_on_close === TRUE) ? 0 : $this->sess_expiration + time();
  // Set the cookie
  setcookie(
     $this->sess_cookie_name,
     $cookie_data,
     $expire,
     $this->cookie_path,
     $this->cookie_domain,
     $this->cookie_secure
    );
 }
 // --------------------------------------------------------------------
 /**
* Serialized array
​*/
 function _serialize($data)
 {
  if (is_array($data))
  {
   foreach ($data as $key => $val)
   {
    if (is_string($val))
    {
     $data[$key] = str_replace('\', '{{slash}}', $val);
    }
   }
  }
  else
  {
   if (is_string($data))
   {
    $data = str_replace('\', '{{slash}}', $data);
   }
  }
  return serialize($data);
 }
 // --------------------------------------------------------------------
 /**
* Deserialize array
​*/
 function _unserialize($data)
 {
  $data = @unserialize(strip_slashes($data));
  if (is_array($data))
  {
   foreach ($data as $key => $val)
   {
    if (is_string($val))
    {
     $data[$key] = str_replace('{{slash}}', '\', $val);
    }
   }
   return $data;
  }
  return (is_string($data)) ? str_replace('{{slash}}', '\', $data) : $data;
 }
 // --------------------------------------------------------------------
 /**
* Recycle/delete invalid session information in the database
​*/
 function _sess_gc()
 {
  if ($this->sess_use_database != TRUE)
  {
   return;
  }
  srand(time());
  if ((rand() % 100) < $this->gc_probability)
  {
   $expire = $this->now - $this->sess_expiration;
   $this->CI->db->where("last_activity < {$expire}");
   $this->CI->db->delete($this->sess_table_name);
   log_message('debug', 'Session garbage collection performed.');
  }
 }
}

php ci 框架中 怎在html页面获取session值？

你说的html页面是模板文件吧，模板文件也是php文件，可以直接
$this->session->userdata('item');
 

拿到一个php源码怎分析它用的是什框架??

If it is a single entry mode, there will be an introduction in index.php
/**
*
**/
If it is your own framework developed by yourself or a team, some It will be marked

http://www.bkjia.com/PHPjc/904912.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/904912.htmlTechArticleCI framework Session.php source code analysis, ci framework session.php CI Session is not a native session, it is All the cookies based on my previous session, in addition, CI can be configured according to user selection...