ecshop改造读写分离的实现方法

<?php
$db_name = "ecshop";
$prefix = "ecs_";
$timezone = "Europe/Berlin";
$cookie_path = "/";
$cookie_domain = "";
$session = "1440";
$_config = array();
//数据库主服务器设置, 支持多组服务器设置, 当设置多组服务器时, 则会随机使用某个服务器
$_config['master'][1]['dbhost'] = "192.168.2.175:3306";
$_config['master'][1]['dbname'] = "ecshop";
$_config['master'][1]['dbuser'] = "dragon";
$_config['master'][1]['dbpw'] = "loong";
/*
*$_config['master'][2]['dbhost'] = "";
*...
*/
//数据库从服务器设置( slave, 只读 ), 支持多组服务器设置, 当设置多组服务器时, 系统每次随机使用
$_config['slave'][1]['dbhost'] = "192.168.2.176:3306";
$_config['slave'][1]['dbname'] = "ecshop";
$_config['slave'][1]['dbuser'] = "ivan";
$_config['slave'][1]['dbpw'] = "loong";
$_config['slave'][2]['dbhost'] = "192.168.2.177:3306";
$_config['slave'][2]['dbname'] = "ecshop";
$_config['slave'][2]['dbuser'] = "ivan";
$_config['slave'][2]['dbpw'] = "loong";
define('EC_CHARSET','utf-8');
define('ADMIN_PATH','admin');
define('AUTH_KEY', 'this is a key');
define('OLD_AUTH_KEY', '');
define('API_TIME', '');
?>

/* 初始化数据库类
* 如果配置了从服务器，则初始化从库类
*/
if(count($_config['slave'])) {
require(ROOT_PATH . 'includes/cls_mysql_slave.php');
$db = new cls_mysql_slave($_config);
}else{
require(ROOT_PATH . 'includes/cls_mysql.php');
$db = new cls_mysql($_config);
}

<?php
require(ROOT_PATH . 'includes/cls_mysql.php');
class cls_mysql_slave extends cls_mysql
{
var $slaveid = null;
function set_config($config){
if(!empty($this->config['slave'])) {
$this->slaveid = array_rand($this->config['slave']);
}
parent::set_config($config);
}
/* 随机分配从库连接 */
function set_slave_config() {
$this->settings = $this->config['slave'][$this->slaveid];
$this->settings['charset'] = $this->config['charset'];
$this->settings['pconnect'] = $this->config['pconnect'];
}
function slave_connect() {
$this->set_slave_config();
$dbhost = $this->settings['dbhost'];
$dbuser = $this->settings['dbuser'];
$dbpw = $this->settings['dbpw'];
$dbname = $this->settings['dbname'];
$this->connect($dbhost, $dbuser, $dbpw, $dbname);
}
function query($sql, $type = '') {
// 如果执行查询操作，则执行从库连接
if($this->slaveid && strtoupper(substr($sql, 0 , 6)) == 'SELECT') {
$this->slave_connect();
}else{
parent::set_config($this->config);
$dbhost = $this->settings['dbhost'];
$dbuser = $this->settings['dbuser'];
$dbpw = $this->settings['dbpw'];
$dbname = $this->settings['dbname'];
$this->connect($dbhost, $dbuser, $dbpw, $dbname);
}
return parent::query($sql, $type);
}
/* 删除失败连接*/
function del_error_link(){
unset($this->config['slave'][$this->slaveid]);
$this->set_config($this->config);
$this->set_slave_config();
$dbhost = $this->settings['dbhost'];
$dbuser = $this->settings['dbuser'];
$dbpw = $this->settings['dbpw'];
$dbname = $this->settings['dbname'];
$this->connect($dbhost, $dbuser, $dbpw, $dbname);
}
}

<?php
if (!defined('IN_ECS'))
{
die('Hacking attempt');
}
class cls_mysql
{
var $link_id = NULL;
var $settings = array();
var $queryCount = 0;
var $linkCount = 0;
var $queryTime = '';
var $queryLog = array();
var $max_cache_time = 300; // 较大的缓存时间，以秒为单位
var $cache_data_dir = 'temp/query_caches/';
var $root_path = '';
var $error_message = array();
var $platform = '';
var $version = '';
var $dbhash = '';
var $starttime = 0;
var $timeline = 0;
var $timezone = 0;
var $mysql_config_cache_file_time = 0;
var $mysql_disable_cache_tables = array(); // 不允许被缓存的表，遇到将不会进行缓存
var $config = array();
function __construct($config, $charset = 'utf8', $pconnect = 0, $quiet = 0)
{
$this->cls_mysql($config, $charset, $pconnect, $quiet);
}
function cls_mysql($config, $charset = 'utf8', $pconnect = 0, $quiet = 0)
{
if(!empty($config)) {
$config['charset'] = $charset;
$config['pconnect'] = $pconnect;
$this->config = $config;
}
if (defined('EC_CHARSET'))
{
$charset = strtolower(str_replace('-', '', EC_CHARSET));
}
if (defined('ROOT_PATH') && !$this->root_path)
{
$this->root_path = ROOT_PATH;
}
$this->set_config($this->config);
if ($quiet)
{
$dbhost = $this->settings['dbhost'];
$dbuser = $this->settings['dbuser'];
$dbpw = $this->settings['dbpw'];
$dbname = $this->settings['dbname'];
$this->connect($dbhost, $dbuser, $dbpw, $dbname, $charset, $pconnect, $quiet);
}
}
//随机分配数据库连接
function set_config($config) {
$sid = array_rand($config['master']);
$settings = $config['master'][$sid];
$settings['sid'] = $sid;
$settings['charset'] = $this->config['charset'];
$settings['pconnect'] = $this->config['pconnect'];
$this->settings = $settings;
}
function connect($dbhost, $dbuser, $dbpw, $dbname = '', $charset = 'utf8', $pconnect = 0, $quiet = 0)
{
if ($pconnect)
{
if (!($this->link_id = @mysql_pconnect($dbhost, $dbuser, $dbpw)))
{
if (!$quiet)
{
$this->ErrorMsg("Can't pConnect MySQL Server!");
}
return false;
}
}
else
{
if (PHP_VERSION >= '4.2')
{
$this->link_id = @mysql_connect($dbhost, $dbuser, $dbpw, true);
}
else
{
$this->link_id = @mysql_connect($dbhost, $dbuser, $dbpw);
mt_srand((double)microtime() * 1000000); // 对 PHP 4.2 以下的版本进行随机数函数的初始化工作
}
if (!$this->link_id)
{
if (!$quiet)
{
//连接超过10次，中断连接，抛出错误
if($this->linkCount>9){
$this->ErrorMsg("Can't Connect MySQL Server!");
}
$this->linkCount++;
$this->del_error_link();
}
return false;
}
}
$this->dbhash = md5($this->root_path . $dbhost . $dbuser . $dbpw . $dbname);
$this->version = mysql_get_server_info($this->link_id);
/* 如果mysql 版本是 4.1+ 以上，需要对字符集进行初始化 */
if ($this->version > '4.1')
{
if ($charset != 'latin1')
{
mysql_query("SET character_set_connection=$charset, character_set_results=$charset, character_set_client=binary", $this->link_id);
}
if ($this->version > '5.0.1')
{
mysql_query("SET sql_mode=''", $this->link_id);
}
}
$sqlcache_config_file = $this->root_path . $this->cache_data_dir . 'sqlcache_config_file_' . $this->dbhash . '.php';
@include($sqlcache_config_file);
$this->starttime = time();
if ($this->max_cache_time && $this->starttime > $this->mysql_config_cache_file_time + $this->max_cache_time)
{
if ($dbhost != '.')
{
$result = mysql_query("SHOW VARIABLES LIKE 'basedir'", $this->link_id);
$row = mysql_fetch_assoc($result);
if (!empty($row['Value']{1}) && $row['Value']{1} == ':' && !empty($row['Value']{2}) && $row['Value']{2} == "\\")
{
$this->platform = 'WINDOWS';
}
else
{
$this->platform = 'OTHER';
}
}
else
{
$this->platform = 'WINDOWS';
}
if ($this->platform == 'OTHER' &&
($dbhost != '.' && strtolower($dbhost) != 'localhost:3306' && $dbhost != '127.0.0.1:3306') ||
(PHP_VERSION >= '5.1' && date_default_timezone_get() == 'UTC'))
{
$result = mysql_query("SELECT UNIX_TIMESTAMP() AS timeline, UNIX_TIMESTAMP('" . date('Y-m-d H:i:s', $this->starttime) . "') AS timezone", $this->link_id);
$row = mysql_fetch_assoc($result);
if ($dbhost != '.' && strtolower($dbhost) != 'localhost:3306' && $dbhost != '127.0.0.1:3306')
{
$this->timeline = $this->starttime - $row['timeline'];
}
if (PHP_VERSION >= '5.1' && date_default_timezone_get() == 'UTC')
{
$this->timezone = $this->starttime - $row['timezone'];
}
}
$content = '<' . "?php\r\n" .
'$this->mysql_config_cache_file_time = ' . $this->starttime . ";\r\n" .
'$this->timeline = ' . $this->timeline . ";\r\n" .
'$this->timezone = ' . $this->timezone . ";\r\n" .
'$this->platform = ' . "'" . $this->platform . "';\r\n?" . '>';
@file_put_contents($sqlcache_config_file, $content);
}
/* 选择数据库 */
if ($dbname)
{
if (mysql_select_db($dbname, $this->link_id) === false )
{
if (!$quiet)
{
$this->ErrorMsg("Can't select MySQL database!");
}
return false;
}
else
{
return true;
}
}
else
{
return true;
}
}
......
/* 删除失败连接*/
function del_error_link(){
unset($this->config['master'][$this->settings['sid']]);
$this->set_config($this->config);
$dbhost = $this->settings['dbhost'];
$dbuser = $this->settings['dbuser'];
$dbpw = $this->settings['dbpw'];
$dbname = $this->settings['dbname'];
$this->connect($dbhost, $dbuser, $dbpw, $dbname);
}
}