<?php
namespace extend\database;
use think\facade\Db;
class Database
{
/**
* 文件指针
* @var resource
*/
private $fp;
/**
* 备份文件信息 part - 卷号，name - 文件名
* @var array
*/
private $file;
/**
* 当前打开文件大小
* @var integer
*/
private $size = 0;
/**
* 备份配置
* @var integer
*/
private $config;
/**
* 数据库备份构造方法
* @param array $file 备份或还原的文件信息
* @param array $config 备份配置信息
* @param string $type 执行类型，export - 备份数据， import - 还原数据
*/
public function __construct($file = [], $config = [], $type = 'export')
{
$this->file = $file;
$this->config = $config;
}
/**
* 查询所有表
*/
public function getTableList()
{
$table_list = Db::query("SHOW TABLE STATUS");
return success([ 'list' => $table_list ]);
}
/**
* 修复表
*/
public function repair($tables)
{
if ($tables) {
Db::startTrans();
try {
if (is_array($tables)) {
$tables = implode('`,`', $tables);
Db::query("REPAIR TABLE `{$tables}`");
} else {
Db::query("REPAIR TABLE `{$tables}`");
}
Db::commit();
return success([], "数据表修复完成");
} catch (\Exception $e) {
// 回滚事务
Db::rollback();
return error([], "数据表修复失败");
}
} else {
return error([], "请指定要修复的表");
}
}
/**
* 打开一个卷，用于写入数据
* @param integer $size 写入数据的大小
*/
private function open($size)
{
if ($this->fp) {
$this->size += $size;
if ($this->size > $this->config[ 'part' ]) {
$this->config[ 'compress' ] ? @gzclose($this->fp) : @fclose($this->fp);
$this->fp = null;
$this->file[ 'part' ]++;
session('backup_file', $this->file);
$this->create();
}
} else {
$backuppath = $this->config[ 'path' ];
$filename = "{$backuppath}{$this->file['name']}-{$this->file['part']}.sql";
if ($this->config[ 'compress' ]) {
$filename = "{$filename}.gz";
$this->fp = @gzopen($filename, "a{$this->config['level']}");
} else {
$this->fp = @fopen($filename, 'a');
}
$this->size = filesize($filename) + $size;
}
}
/**
* 写入初始数据
* @return boolean true - 写入成功，false - 写入失败
*/
public function create()
{
$config = config('database');
$sql = "-- -----------------------------\n";
$sql .= "-- Niucloud MySQL Data Transfer \n";
$sql .= "-- author niuteam \n";
$sql .= "-- \n";
$sql .= "-- Host : " . $config[ 'connections' ][ 'mysql' ][ 'hostname' ] . "\n";
$sql .= "-- Port : " . $config[ 'connections' ][ 'mysql' ][ 'hostport' ] . "\n";
$sql .= "-- Database : " . $config[ 'connections' ][ 'mysql' ][ 'database' ] . "\n";
$sql .= "-- \n";
$sql .= "-- Part : #{$this->file['part']}\n";
$sql .= "-- Date : " . date("Y-m-d H:i:s") . "\n";
$sql .= "-- -----------------------------\n\n";
$sql .= "SET FOREIGN_KEY_CHECKS = 0;\n\n";
return $this->write($sql);
}
/**
* 写入SQL语句
* @param string $sql 要写入的SQL语句
* @return boolean true - 写入成功，false - 写入失败！
*/
private function write($sql)
{
$size = strlen($sql);
//由于压缩原因，无法计算出压缩后的长度，这里假设压缩率为50%，
//一般情况压缩率都会高于50%；
$size = $this->config[ 'compress' ] ? $size / 2 : $size;
$this->open($size);
return $this->config[ 'compress' ] ? @gzwrite($this->fp, $sql) : @fwrite($this->fp, $sql);
}
/**
* 备份表结构
* @param string $table 表名
* @param integer $start 起始行数
* @return boolean false - 备份失败
*/
public function backup($table, $start)
{
//备份表结构
if (0 == $start) {
$result = Db::query("SHOW CREATE TABLE `{$table}`");
$sql = "\n";
$sql .= "-- -----------------------------\n";
$sql .= "-- Table structure for `{$table}`\n";
$sql .= "-- -----------------------------\n";
$sql .= "DROP TABLE IF EXISTS `{$table}`;\n";
$sql .= trim($result[ 0 ][ 'Create Table' ]) . ";\n\n";
if (false === $this->write($sql)) {
return false;
}
}
//数据总数
$result = Db::query("SELECT COUNT(*) AS count FROM `{$table}`");
$count = $result[ '0' ][ 'count' ];
//备份表数据
if ($count) {
//写入数据注释
if (0 == $start) {
$sql = "-- -----------------------------\n";
$sql .= "-- Records of `{$table}`\n";
$sql .= "-- -----------------------------\n";
$this->write($sql);
}
//备份数据记录
$result = Db::query("SELECT * FROM `{$table}`");
foreach ($result as $row) {
$row = array_map(
function($item) {
if (is_json($item)) {
return json_encode(json_decode($item, true), JSON_UNESCAPED_UNICODE);
} else {
return $item;
}
},
$row
);
$sql = "INSERT INTO `{$table}` VALUES ('" . implode("', '", $row) . "');\n";
if (false === $this->write($sql)) {
return false;
}
}
}
//备份下一表
return 0;
}
/**
* 还原表数据
* @param unknown $start
*/
public function import($start)
{
//还原数据
if ($this->config[ 'compress' ]) {
$gz = gzopen($this->file[ 1 ], 'r');
$size = 0;
} else {
$size = filesize($this->file[ 1 ]);
$gz = fopen($this->file[ 1 ], 'r');
}
$sql = '';
if ($start) {
$this->config[ 'compress' ] ? gzseek($gz, $start) : fseek($gz, $start);
}
for ($i = 0; $i < 1000; $i++) {
$sql .= $this->config[ 'compress' ] ? gzgets($gz) : fgets($gz);
if (preg_match('/.*;$/', trim($sql))) {
// Log::write('恢复sql'.$sql);
if (false !== Db::execute($sql)) {
$start += strlen($sql);
} else {
return false;
}
$sql = '';
} elseif ($this->config[ 'compress' ] ? gzeof($gz) : feof($gz)) {
return 0;
}
}
return array ( $start, $size );
}
/**
* 析构方法，用于关闭文件资源
*/
public function __destruct()
{
$this->config[ 'compress' ] ? @gzclose($this->fp) : @fclose($this->fp);
}
}