lychee/php/Modules/Database.php
2016-05-02 19:51:21 +02:00

421 lines
11 KiB
PHP
Executable File

<?php
namespace Lychee\Modules;
use Mysqli;
final class Database {
private $connection = null;
private static $instance = null;
private static $versions = array(
'020700', // 2.7.0
'030000', // 3.0.0
'030001', // 3.0.1
'030003', // 3.0.3
'030100', // 3.1.0
'030102' // 3.1.2
);
/**
* @return object Returns a new or cached connection.
*/
public static function get() {
if (!self::$instance) {
$credentials = Config::get();
self::$instance = new self(
$credentials['host'],
$credentials['user'],
$credentials['password'],
$credentials['name'],
$credentials['prefix']
);
}
return self::$instance->connection;
}
/**
* Exits on error.
* @return boolean Returns true when successful.
*/
private function __construct($host, $user, $password, $name = 'lychee', $dbTablePrefix) {
// Check dependencies
Validator::required(isset($host, $user, $password, $name), __METHOD__);
// Define the table prefix
defineTablePrefix($dbTablePrefix);
// Open a new connection to the MySQL server
$connection = self::connect($host, $user, $password);
// Check if the connection was successful
if ($connection===false) Response::error(self::connect_error());
if (self::setCharset($connection)===false) Response::error('Could not set database charset!');
// Create database
if (self::createDatabase($connection, $name)===false) Response::error('Could not create database!');
// Create tables
if (self::createTables($connection)===false) Response::error('Could not create tables!');
// Update database
if (self::update($connection, $name)===false) Response::error('Could not update database and tables!');
$this->connection = $connection;
return true;
}
/**
* @return object|false Returns the connection when successful.
*/
public static function connect($host = 'localhost', $user, $password) {
// Open a new connection to the MySQL server
$connection = @new Mysqli($host, $user, $password);
// Check if the connection was successful
if ($connection->connect_errno) return false;
return $connection;
}
/**
* @return string Returns the string description of the last connect error
*/
private static function connect_error() {
return mysqli_connect_error();
}
/**
* @return boolean Returns true when successful.
*/
private static function setCharset($connection) {
// Check dependencies
Validator::required(isset($connection), __METHOD__);
// Avoid sql injection on older MySQL versions by using GBK
if ($connection->server_version<50500) @$connection->set_charset('GBK');
else @$connection->set_charset('utf8');
// Set unicode
$query = 'SET NAMES utf8';
$result = self::execute($connection, $query, null, null);
if ($result===false) return false;
return true;
}
/**
* @return boolean Returns true when successful.
*/
public static function createDatabase($connection, $name = 'lychee') {
// Check dependencies
Validator::required(isset($connection), __METHOD__);
// Check if database exists
if ($connection->select_db($name)===true) return true;
// Create database
$query = self::prepare($connection, 'CREATE DATABASE IF NOT EXISTS ?', array($name));
$result = self::execute($connection, $query, null, null);
if ($result===false) return false;
if ($connection->select_db($name)===false) return false;
return true;
}
/**
* @return boolean Returns true when successful.
*/
private static function createTables($connection) {
// Check dependencies
Validator::required(isset($connection), __METHOD__);
// Check if tables exist
$query = self::prepare($connection, 'SELECT * FROM ?, ?, ?, ? LIMIT 0', array(LYCHEE_TABLE_PHOTOS, LYCHEE_TABLE_ALBUMS, LYCHEE_TABLE_SETTINGS, LYCHEE_TABLE_LOG));
$result = self::execute($connection, $query, null, null);
if ($result!==false) return true;
// Check if log table exists
$exist = self::prepare($connection, 'SELECT * FROM ? LIMIT 0', array(LYCHEE_TABLE_LOG));
$result = self::execute($connection, $exist, null, null);
if ($result===false) {
// Read file
$file = __DIR__ . '/../database/log_table.sql';
$query = @file_get_contents($file);
if ($query===false) return false;
// Create table
$query = self::prepare($connection, $query, array(LYCHEE_TABLE_LOG));
$result = self::execute($connection, $query, null, null);
if ($result===false) return false;
}
// Check if settings table exists
$exist = self::prepare($connection, 'SELECT * FROM ? LIMIT 0', array(LYCHEE_TABLE_SETTINGS));
$result = self::execute($connection, $exist, __METHOD__, __LINE__);
if ($result===false) {
// Read file
$file = __DIR__ . '/../database/settings_table.sql';
$query = @file_get_contents($file);
if ($query===false) {
Log::error($connection, __METHOD__, __LINE__, 'Could not load query for lychee_settings');
return false;
}
// Create table
$query = self::prepare($connection, $query, array(LYCHEE_TABLE_SETTINGS));
$result = self::execute($connection, $query, __METHOD__, __LINE__);
if ($result===false) return false;
// Read file
$file = __DIR__ . '/../database/settings_content.sql';
$query = @file_get_contents($file);
if ($query===false) {
Log::error($connection, __METHOD__, __LINE__, 'Could not load content-query for lychee_settings');
return false;
}
// Add content
$query = self::prepare($connection, $query, array(LYCHEE_TABLE_SETTINGS));
$result = self::execute($connection, $query, __METHOD__, __LINE__);
if ($result===false) return false;
// Generate identifier
$identifier = md5(microtime(true));
$query = self::prepare($connection, "UPDATE `?` SET `value` = '?' WHERE `key` = 'identifier' LIMIT 1", array(LYCHEE_TABLE_SETTINGS, $identifier));
$result = self::execute($connection, $query, __METHOD__, __LINE__);
if ($result===false) return false;
}
// Check if albums table exists
$exist = self::prepare($connection, 'SELECT * FROM ? LIMIT 0', array(LYCHEE_TABLE_ALBUMS));
$result = self::execute($connection, $exist, __METHOD__, __LINE__);
if ($result===false) {
// Read file
$file = __DIR__ . '/../database/albums_table.sql';
$query = @file_get_contents($file);
if ($query===false) {
Log::error($connection, __METHOD__, __LINE__, 'Could not load query for lychee_albums');
return false;
}
// Create table
$query = self::prepare($connection, $query, array(LYCHEE_TABLE_ALBUMS));
$result = self::execute($connection, $query, __METHOD__, __LINE__);
if ($result===false) return false;
}
// Check if photos table exists
$exist = self::prepare($connection, 'SELECT * FROM ? LIMIT 0', array(LYCHEE_TABLE_PHOTOS));
$result = self::execute($connection, $exist, __METHOD__, __LINE__);
if ($result===false) {
// Read file
$file = __DIR__ . '/../database/photos_table.sql';
$query = @file_get_contents($file);
if ($query===false) {
Log::error($connection, __METHOD__, __LINE__, 'Could not load query for lychee_photos');
return false;
}
// Create table
$query = self::prepare($connection, $query, array(LYCHEE_TABLE_PHOTOS));
$result = self::execute($connection, $query, __METHOD__, __LINE__);
if ($result===false) return false;
}
return true;
}
/**
* Exits when an update fails.
* @return boolean Returns true when successful.
*/
private static function update($connection, $dbName) {
// Check dependencies
Validator::required(isset($connection, $dbName), __METHOD__);
// Get current version
$query = self::prepare($connection, "SELECT * FROM ? WHERE `key` = 'version'", array(LYCHEE_TABLE_SETTINGS));
$result = self::execute($connection, $query, __METHOD__, __LINE__);
if ($result===false) return false;
// Extract current version
$current = $result->fetch_object()->value;
// For each update
foreach (self::$versions as $version) {
// Only update when newer version available
if ($version<=$current) continue;
// Load update
include(__DIR__ . '/../database/update_' . $version . '.php');
}
return true;
}
/**
* @return boolean Returns true when successful.
*/
public static function setVersion($connection, $version) {
// Check dependencies
Validator::required(isset($connection), __METHOD__);
$query = self::prepare($connection, "UPDATE ? SET value = '?' WHERE `key` = 'version'", array(LYCHEE_TABLE_SETTINGS, $version));
$result = self::execute($connection, $query, __METHOD__, __LINE__);
if ($result===false) return false;
return true;
}
/**
* @return string Returns a escaped query.
*/
public static function prepare($connection, $query, array $data) {
// Check dependencies
Validator::required(isset($connection, $query), __METHOD__);
// Count the number of placeholders and compare it with the number of arguments
// If it doesn't match, calculate the difference and skip this number of placeholders before starting the replacement
// This avoids problems with placeholders in user-input
// $skip = Number of placeholders which need to be skipped
$skip = 0;
$temp = '';
$num = array(
'placeholder' => substr_count($query, '?'),
'data' => count($data)
);
if (($num['data']-$num['placeholder'])<0) Log::notice($connection, __METHOD__, __LINE__, 'Could not completely prepare query. Query has more placeholders than values.');
foreach ($data as $value) {
// Escape
$value = mysqli_real_escape_string($connection, $value);
// Recalculate number of placeholders
$num['placeholder'] = substr_count($query, '?');
// Calculate number of skips
if ($num['placeholder']>$num['data']) $skip = $num['placeholder'] - $num['data'];
if ($skip>0) {
// Need to skip $skip placeholders, because the user input contained placeholders
// Calculate a substring which does not contain the user placeholders
// 1 or -1 is the length of the placeholder (placeholder = ?)
$pos = -1;
for ($i=$skip; $i>0; $i--) $pos = strpos($query, '?', $pos + 1);
$pos++;
$temp = substr($query, 0, $pos); // First part of $query
$query = substr($query, $pos); // Last part of $query
}
// Put a backslash in front of every character that is part of the regular
// expression syntax. Avoids a backreference when using preg_replace.
$value = preg_quote($value);
// Replace
$query = preg_replace('/\?/', $value, $query, 1);
if ($skip>0) {
// Reassemble the parts of $query
$query = $temp . $query;
}
// Reset skip
$skip = 0;
// Decrease number of data elements
$num['data']--;
}
return $query;
}
/**
* @return object|false Returns the results on success.
*/
public static function execute($connection, $query, $function, $line) {
// Check dependencies
Validator::required(isset($connection, $query), __METHOD__);
// Only activate logging when $function and $line is set
$logging = ($function===null||$line===null ? false : true);
// Execute query
$result = $connection->query($query);
// Check if execution failed
if ($result===false) {
if ($logging===true) Log::error($connection, $function, $line, $connection->error);
return false;
}
return $result;
}
}
?>