<?php
/* μlogger
*
* Copyright(C) 2017 Bartek Fabiszewski (www.fabiszewski.net)
*
* This is free software; you can redistribute it and/or modify it under
* the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
require_once(ROOT_DIR . "/helpers/utils.php");
/**
* PDO wrapper
*/
class uDb extends PDO {
/**
* Singleton instance
*
* @var uDb Object instance
*/
protected static $instance;
/**
* Table names
*
* @var array Array of names
*/
protected static $tables;
/**
* Database driver name
*
* @var string Driver
*/
protected static $driver;
/**
* @var string Database DSN
*/
private static $dbdsn = "";
/**
* @var string Database user
*/
private static $dbuser = "";
/**
* @var string Database pass
*/
private static $dbpass = "";
/**
* @var string Optional table names prefix, eg. "ulogger_"
*/
private static $dbprefix = "";
/**
* PDO constuctor
*
* @param string $dsn
* @param string $user
* @param string $pass
*/
public function __construct($dsn, $user, $pass) {
try {
$options = [
PDO::ATTR_EMULATE_PREPARES => false, // try to use native prepared statements
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION, // throw exceptions
PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC, // return assoc array by default
];
@parent::__construct($dsn, $user, $pass, $options);
self::$driver = $this->getAttribute(PDO::ATTR_DRIVER_NAME);
$this->setCharset("utf8");
$this->initTables();
} catch (PDOException $e) {
header("HTTP/1.1 503 Service Unavailable");
die("Database connection error (" . $e->getMessage() . ")");
}
}
/**
* Initialize table names based on config
*/
private function initTables() {
self::$tables = [];
$prefix = preg_replace('/[^a-z0-9_]/i', '', self::$dbprefix);
self::$tables['positions'] = $prefix . "positions";
self::$tables['tracks'] = $prefix . "tracks";
self::$tables['users'] = $prefix . "users";
self::$tables['config'] = $prefix . "config";
self::$tables['ol_layers'] = $prefix . "ol_layers";
}
/**
* Returns singleton instance
*
* @return uDb Singleton instance
*/
public static function getInstance() {
if (!self::$instance) {
self::getConfig();
self::$instance = new self(self::$dbdsn, self::$dbuser, self::$dbpass);
}
return self::$instance;
}
/**
* Read database setup from config file
* @noinspection IssetArgumentExistenceInspection
* @noinspection PhpIncludeInspection
*/
private static function getConfig() {
$configFile = dirname(__DIR__) . "/config.php";
if (!file_exists($configFile)) {
header("HTTP/1.1 503 Service Unavailable");
die("Missing config.php file!");
}
include($configFile);
if (isset($dbdsn)) {
self::$dbdsn = self::normalizeDsn($dbdsn);
}
if (isset($dbuser)) {
self::$dbuser = $dbuser;
}
if (isset($dbpass)) {
self::$dbpass = $dbpass;
}
if (isset($dbprefix)) {
self::$dbprefix = $dbprefix;
}
}
/**
* Get full table name including prefix
*
* @param string $name Name
* @return string Full table name
*/
public function table($name) {
return self::$tables[$name];
}
/**
* Returns function name for getting date-time column value as unix timestamp
* @param string $column
* @return string
*/
public function unix_timestamp($column) {
switch (self::$driver) {
default:
case "mysql":
return "UNIX_TIMESTAMP($column)";
break;
case "pgsql":
return "EXTRACT(EPOCH FROM $column::TIMESTAMP WITH TIME ZONE)";
break;
case "sqlite":
return "STRFTIME('%s', $column)";
break;
}
}
/**
* Returns placeholder for LOB data types
* @return string
*/
public function lobPlaceholder() {
switch (self::$driver) {
default:
case "mysql":
case "sqlite":
return "?";
break;
case "pgsql":
return "?::bytea";
break;
}
}
/**
* Returns construct for getting LOB as string
* @param string $column Column name
* @return string
*/
public function from_lob($column) {
switch (self::$driver) {
default:
case "mysql":
case "sqlite":
return $column;
break;
case "pgsql":
return "encode($column, 'escape') AS $column";
break;
}
}
/**
* Returns function name for getting date-time column value as 'YYYY-MM-DD hh:mm:ss'
* @param string $column
* @return string
*/
public function from_unixtime($column) {
switch (self::$driver) {
default:
case "mysql":
return "FROM_UNIXTIME($column)";
break;
case "pgsql":
return "TO_TIMESTAMP($column)";
break;
case "sqlite":
return "DATETIME($column, 'unixepoch')";
break;
}
}
/**
* Replace into
* Note: requires PostgreSQL >= 9.5
* @param string $table Table name (without prefix)
* @param string[] $columns Column names
* @param string[][] $values Values [ [ value1, value2 ], ... ]
* @param string $key Unique column
* @param string $update Updated column
* @return string
*/
public function insertOrReplace($table, $columns, $values, $key, $update) {
$cols = implode(", ", $columns);
$rows = [];
foreach ($values as $row) {
$rows[] = "(" . implode(", ", $row) . ")";
}
$vals = implode(", ", $rows);
switch (self::$driver) {
default:
case "mysql":
return "INSERT INTO {$this->table($table)} ($cols)
VALUES $vals
ON DUPLICATE KEY UPDATE $update = VALUES($update)";
break;
case "pgsql":
return "INSERT INTO {$this->table($table)} ($cols)
VALUES $vals
ON CONFLICT ($key) DO UPDATE SET $update = EXCLUDED.$update";
break;
case "sqlite":
return "REPLACE INTO {$this->table($table)} ($cols)
VALUES $vals";
break;
}
}
/**
* Set character set
* @param string $charset
*/
private function setCharset($charset) {
if (self::$driver === "pgsql" || self::$driver === "mysql") {
$this->exec("SET NAMES '$charset'");
}
}
/**
* Extract database name from DSN
* @param string $dsn
* @return string Empty string if not found
*/
public static function getDbName($dsn) {
$name = "";
if ($dsn && strpos($dsn, ":") !== false) {
list($scheme, $dsnWithoutScheme) = explode(":", $dsn, 2);
switch ($scheme) {
case "sqlite":
case "sqlite2":
case "sqlite3":
$pattern = "/(.+)/";
break;
case "pgsql":
$pattern = "/dbname=([^; ]+)/";
break;
default:
$pattern = "/dbname=([^;]+)/";
break;
}
$result = preg_match($pattern, $dsnWithoutScheme, $matches);
if ($result === 1) {
$name = $matches[1];
}
}
return $name;
}
/**
* Normalize DSN.
* Make sure sqlite DSN file path is absolute
* @param string $dsn DSN
* @return string Normalized DSN
*/
public static function normalizeDsn($dsn) {
if (stripos($dsn, "sqlite") !== 0) {
return $dsn;
}
$arr = explode(":", $dsn, 2);
if (count($arr) < 2 || empty($arr[1]) || uUtils::isAbsolutePath($arr[1])) {
return $dsn;
}
$scheme = $arr[0];
$path = dirname(__DIR__) . DIRECTORY_SEPARATOR . $arr[1];
return $scheme . ":" . realpath(dirname($path)) . DIRECTORY_SEPARATOR . basename(($path));
}
}
?>