PHP absolute path to root

Question

I can't believe PHP doesn't have an easy solution for this simple matter. ASP.NET has a ~ sign that takes care of this issue and starts everything from the root level. Here's my problem:

localhost/MySite
   -->Admin
      -- Edit.php
   -->Class
      -- class.EditInfo.php
   -->Texts
      -- MyInfo.txt
   --ShowInfo.php

Inside class.EditInfo.php I am accessing MyInfo.txt so I defined a relative path "../Texts/MyInfo.txt". Then I created an object of EditInfo in Admin/Edit.php and accessed Texts/MyInfo.txt - it worked fine.

But now I have to create an object of EditInfo in ShowInfo.php and access Texts/MyInfo.txt and here's the problem that occurs. As I am using a relative path in my class, whenever I am creating an objEditInfo and trying to access MyInfo.txt I am getting "File doesn't exist" error.

Now I am looking for something that's equivalent to "~/Texts/MyInfo.txt" from ASP.NET. Is there anything similar to that out there??? Or do I have to set the path with some if/else condition?

---

UPDATE:

I used $_SERVER['DOCUMENT_ROOT']. I was using a subfolder where my actual website was. So I had to use $_SERVER['DOCUMENT_ROOT']."/mySite" & then adding rest of the address ("/Texts/MyInfo.php") to it.

Erminiaerminie

Create a constant with absolute path to the root and use it – Weakness

possible duplicate of PHP how to find application root? – Foldaway

Answer 1

Create a constant with absolute path to the root by using define in ShowInfo.php:

define('ROOTPATH', __DIR__);

Or PHP <= 5.3

define('ROOTPATH', dirname(__FILE__));

Now use it:

if (file_exists(ROOTPATH.'/Texts/MyInfo.txt')) {
  // ...
}

Or use the DOCUMENT_ROOT defined in $_SERVER:

if (file_exists($_SERVER['DOCUMENT_ROOT'].'/Texts/MyInfo.txt')) {
  // ...
}

Quincentenary

Can we use ROOTPATH for href (a tag) ? – Hoffert

@BBeta It's not clear what you mean, but there shouldn't be any difference where you use it. The above code is just storing a path as a string/constant. You can then recall it and use it wherever appropriate. – Sianna

But wouldn't that make it fail when accessing from Admin/Edit.php ? _ _ DIR _ _ will point to /path/to/site/Admin, so it will try to access /path/to/site/Admin/Texts, instead of /path/to/site/texts. – Epergne

Answer 2

In PHP there is a global variable containing various details related to the server. It's called $_SERVER. It contains also the root:

 $_SERVER['DOCUMENT_ROOT']

The only problem is that the entries in this variable are provided by the web server and there is no guarantee that all web servers offer them.

Deering

Answer 3

It always best to start any custom PHP project with a bootstrap file where you define the most commonly used paths as constants, based on values extracted from $_SERVER. It should make migrating your projects or parts of your project to another server or to another directory on the server a hell of a lot easier.

This is how I define my root paths :

define("LOCAL_PATH_ROOT", $_SERVER["DOCUMENT_ROOT"]);
define("HTTP_PATH_ROOT", isset($_SERVER["HTTP_HOST"]) ? $_SERVER["HTTP_HOST"] : (isset($_SERVER["SERVER_NAME"]) ? $_SERVER["SERVER_NAME"] : '_UNKNOWN_'));

The path LOCAL_PATH_ROOT is the document root. The path HTTP_PATH_ROOT is the equivalent when accessing the same path via HTTP.

At that point, converting any local path to an HTTP path can be done with the following code :

str_replace(LOCAL_PATH_ROOT, RELATIVE_PATH_ROOT, $my_path)

If you want to ensure compatibility with Windows based servers, you'll need to replace the directory seperator with a URL seperator as well :

str_replace(LOCAL_PATH_ROOT, RELATIVE_PATH_ROOT, str_replace(DIRECTORY_SEPARATOR, '/', $my_path))

Here's the full bootstrap code that I'm using for the PHP PowerTools boilerplate :

defined('LOCAL_PATH_BOOTSTRAP') || define("LOCAL_PATH_BOOTSTRAP", __DIR__);

// -----------------------------------------------------------------------
// DEFINE SEPERATOR ALIASES
// -----------------------------------------------------------------------
define("URL_SEPARATOR", '/');
define("DS", DIRECTORY_SEPARATOR);
define("PS", PATH_SEPARATOR);
define("US", URL_SEPARATOR);

// -----------------------------------------------------------------------
// DEFINE ROOT PATHS
// -----------------------------------------------------------------------
define("RELATIVE_PATH_ROOT", '');
define("LOCAL_PATH_ROOT", $_SERVER["DOCUMENT_ROOT"]);
define("HTTP_PATH_ROOT",
        isset($_SERVER["HTTP_HOST"]) ?
        $_SERVER["HTTP_HOST"] : (
        isset($_SERVER["SERVER_NAME"]) ?
        $_SERVER["SERVER_NAME"] : '_UNKNOWN_'));

// -----------------------------------------------------------------------
// DEFINE RELATIVE PATHS
// -----------------------------------------------------------------------
define("RELATIVE_PATH_BASE",
        str_replace(LOCAL_PATH_ROOT, RELATIVE_PATH_ROOT, getcwd()));
define("RELATIVE_PATH_APP", dirname(RELATIVE_PATH_BASE));
define("RELATIVE_PATH_LIBRARY", RELATIVE_PATH_APP . DS . 'vendor');
define("RELATIVE_PATH_HELPERS", RELATIVE_PATH_BASE);
define("RELATIVE_PATH_TEMPLATE", RELATIVE_PATH_BASE . DS . 'templates');
define("RELATIVE_PATH_CONFIG", RELATIVE_PATH_BASE . DS . 'config');
define("RELATIVE_PATH_PAGES", RELATIVE_PATH_BASE . DS . 'pages');
define("RELATIVE_PATH_ASSET", RELATIVE_PATH_BASE . DS . 'assets');
define("RELATIVE_PATH_ASSET_IMG", RELATIVE_PATH_ASSET . DS . 'img');
define("RELATIVE_PATH_ASSET_CSS", RELATIVE_PATH_ASSET . DS . 'css');
define("RELATIVE_PATH_ASSET_JS", RELATIVE_PATH_ASSET . DS . 'js');

// -----------------------------------------------------------------------
// DEFINE LOCAL PATHS
// -----------------------------------------------------------------------
define("LOCAL_PATH_BASE", LOCAL_PATH_ROOT . RELATIVE_PATH_BASE);
define("LOCAL_PATH_APP", LOCAL_PATH_ROOT . RELATIVE_PATH_APP);
define("LOCAL_PATH_LIBRARY", LOCAL_PATH_ROOT . RELATIVE_PATH_LIBRARY);
define("LOCAL_PATH_HELPERS", LOCAL_PATH_ROOT . RELATIVE_PATH_HELPERS);
define("LOCAL_PATH_TEMPLATE", LOCAL_PATH_ROOT . RELATIVE_PATH_TEMPLATE);
define("LOCAL_PATH_CONFIG", LOCAL_PATH_ROOT . RELATIVE_PATH_CONFIG);
define("LOCAL_PATH_PAGES", LOCAL_PATH_ROOT . RELATIVE_PATH_PAGES);
define("LOCAL_PATH_ASSET", LOCAL_PATH_ROOT . RELATIVE_PATH_ASSET);
define("LOCAL_PATH_ASSET_IMG", LOCAL_PATH_ROOT . RELATIVE_PATH_ASSET_IMG);
define("LOCAL_PATH_ASSET_CSS", LOCAL_PATH_ROOT . RELATIVE_PATH_ASSET_CSS);
define("LOCAL_PATH_ASSET_JS", LOCAL_PATH_ROOT . RELATIVE_PATH_ASSET_JS);

// -----------------------------------------------------------------------
// DEFINE URL PATHS
// -----------------------------------------------------------------------
if (US === DS) { // needed for compatibility with windows
    define("HTTP_PATH_BASE", HTTP_PATH_ROOT . RELATIVE_PATH_BASE);
    define("HTTP_PATH_APP", HTTP_PATH_ROOT . RELATIVE_PATH_APP);
    define("HTTP_PATH_LIBRARY", false);
    define("HTTP_PATH_HELPERS", false);
    define("HTTP_PATH_TEMPLATE", false);
    define("HTTP_PATH_CONFIG", false);
    define("HTTP_PATH_PAGES", false);
    define("HTTP_PATH_ASSET", HTTP_PATH_ROOT . RELATIVE_PATH_ASSET);
    define("HTTP_PATH_ASSET_IMG", HTTP_PATH_ROOT . RELATIVE_PATH_ASSET_IMG);
    define("HTTP_PATH_ASSET_CSS", HTTP_PATH_ROOT . RELATIVE_PATH_ASSET_CSS);
    define("HTTP_PATH_ASSET_JS", HTTP_PATH_ROOT . RELATIVE_PATH_ASSET_JS);
} else {
    define("HTTP_PATH_BASE", HTTP_PATH_ROOT .
            str_replace(DS, US, RELATIVE_PATH_BASE));
    define("HTTP_PATH_APP", HTTP_PATH_ROOT .
            str_replace(DS, US, RELATIVE_PATH_APP));
    define("HTTP_PATH_LIBRARY", false);
    define("HTTP_PATH_HELPERS", false);
    define("HTTP_PATH_TEMPLATE", false);
    define("HTTP_PATH_CONFIG", false);
    define("HTTP_PATH_PAGES", false);
    define("HTTP_PATH_ASSET", HTTP_PATH_ROOT .
            str_replace(DS, US, RELATIVE_PATH_ASSET));
    define("HTTP_PATH_ASSET_IMG", HTTP_PATH_ROOT .
            str_replace(DS, US, RELATIVE_PATH_ASSET_IMG));
    define("HTTP_PATH_ASSET_CSS", HTTP_PATH_ROOT .
            str_replace(DS, US, RELATIVE_PATH_ASSET_CSS));
    define("HTTP_PATH_ASSET_JS", HTTP_PATH_ROOT .
            str_replace(DS, US, RELATIVE_PATH_ASSET_JS));
}

// -----------------------------------------------------------------------
// DEFINE REQUEST PARAMETERS
// -----------------------------------------------------------------------
define("REQUEST_QUERY",
        isset($_SERVER["QUERY_STRING"]) && $_SERVER["QUERY_STRING"] != '' ?
        $_SERVER["QUERY_STRING"] : false);
define("REQUEST_METHOD",
        isset($_SERVER["REQUEST_METHOD"]) ?
        strtoupper($_SERVER["REQUEST_METHOD"]) : false);
define("REQUEST_STATUS",
        isset($_SERVER["REDIRECT_STATUS"]) ?
        $_SERVER["REDIRECT_STATUS"] : false);
define("REQUEST_PROTOCOL",
        isset($_SERVER["HTTP_ORIGIN"]) ?
        substr($_SERVER["HTTP_ORIGIN"], 0,
        strpos($_SERVER["HTTP_ORIGIN"], '://') + 3) : 'http://');
define("REQUEST_PATH",
        isset($_SERVER["REQUEST_URI"]) ?
        str_replace(RELATIVE_PATH_BASE, '',
        $_SERVER["REQUEST_URI"]) : '_UNKNOWN_');
define("REQUEST_PATH_STRIP_QUERY",
        REQUEST_QUERY ?
        str_replace('?' . REQUEST_QUERY, '', REQUEST_PATH) : REQUEST_PATH);

// -----------------------------------------------------------------------
// DEFINE SITE PARAMETERS
// -----------------------------------------------------------------------
define("PRODUCTION", false);
define("PAGE_PATH_DEFAULT", US . 'index');
define("PAGE_PATH",
        (REQUEST_PATH_STRIP_QUERY === US) ?
        PAGE_PATH_DEFAULT : REQUEST_PATH_STRIP_QUERY);

If you add the above code to your own project, outputting all user constants at this point (which you can do with get_defined_constants(true) should give a result that looks somewhat like this :

array (
  'LOCAL_PATH_BOOTSTRAP' => '/var/www/libraries/backend/Data/examples',
  'URL_SEPARATOR' => '/',
  'DS' => '/',
  'PS' => ':',
  'US' => '/',
  'RELATIVE_PATH_ROOT' => '',
  'LOCAL_PATH_ROOT' => '/var/www',
  'HTTP_PATH_ROOT' => 'localhost:8888',
  'RELATIVE_PATH_BASE' => '/libraries/backend/Data/examples',
  'RELATIVE_PATH_APP' => '/libraries/backend/Data',
  'RELATIVE_PATH_LIBRARY' => '/libraries/backend/Data/vendor',
  'RELATIVE_PATH_HELPERS' => '/libraries/backend/Data/examples',
  'RELATIVE_PATH_TEMPLATE' => '/libraries/backend/Data/examples/templates',
  'RELATIVE_PATH_CONFIG' => '/libraries/backend/Data/examples/config',
  'RELATIVE_PATH_PAGES' => '/libraries/backend/Data/examples/pages',
  'RELATIVE_PATH_ASSET' => '/libraries/backend/Data/examples/assets',
  'RELATIVE_PATH_ASSET_IMG' => '/libraries/backend/Data/examples/assets/img',
  'RELATIVE_PATH_ASSET_CSS' => '/libraries/backend/Data/examples/assets/css',
  'RELATIVE_PATH_ASSET_JS' => '/libraries/backend/Data/examples/assets/js',
  'LOCAL_PATH_BASE' => '/var/www/libraries/backend/Data/examples',
  'LOCAL_PATH_APP' => '/var/www/libraries/backend/Data',
  'LOCAL_PATH_LIBRARY' => '/var/www/libraries/backend/Data/vendor',
  'LOCAL_PATH_HELPERS' => '/var/www/libraries/backend/Data/examples',
  'LOCAL_PATH_TEMPLATE' => '/var/www/libraries/backend/Data/examples/templates',
  'LOCAL_PATH_CONFIG' => '/var/www/libraries/backend/Data/examples/config',
  'LOCAL_PATH_PAGES' => '/var/www/libraries/backend/Data/examples/pages',
  'LOCAL_PATH_ASSET' => '/var/www/libraries/backend/Data/examples/assets',
  'LOCAL_PATH_ASSET_IMG' => '/var/www/libraries/backend/Data/examples/assets/img',
  'LOCAL_PATH_ASSET_CSS' => '/var/www/libraries/backend/Data/examples/assets/css',
  'LOCAL_PATH_ASSET_JS' => '/var/www/libraries/backend/Data/examples/assets/js',
  'HTTP_PATH_BASE' => 'localhost:8888/libraries/backend/Data/examples',
  'HTTP_PATH_APP' => 'localhost:8888/libraries/backend/Data',
  'HTTP_PATH_LIBRARY' => false,
  'HTTP_PATH_HELPERS' => false,
  'HTTP_PATH_TEMPLATE' => false,
  'HTTP_PATH_CONFIG' => false,
  'HTTP_PATH_PAGES' => false,
  'HTTP_PATH_ASSET' => 'localhost:8888/libraries/backend/Data/examples/assets',
  'HTTP_PATH_ASSET_IMG' => 'localhost:8888/libraries/backend/Data/examples/assets/img',
  'HTTP_PATH_ASSET_CSS' => 'localhost:8888/libraries/backend/Data/examples/assets/css',
  'HTTP_PATH_ASSET_JS' => 'localhost:8888/libraries/backend/Data/examples/assets/js',
  'REQUEST_QUERY' => false,
  'REQUEST_METHOD' => 'GET',
  'REQUEST_STATUS' => false,
  'REQUEST_PROTOCOL' => 'http://',
  'REQUEST_PATH' => '/',
  'REQUEST_PATH_STRIP_QUERY' => '/',
  'PRODUCTION' => false,
  'PAGE_PATH_DEFAULT' => '/index',
  'PAGE_PATH' => '/index',
)

Monteria

Answer 4

You can access the $_SERVER['DOCUMENT_ROOT'] variable :

<?php 
   $path = $_SERVER['DOCUMENT_ROOT'];
   $path .= "/subdir1/yourdocument.txt";
?>

Sedda

You're probably better off defining $_SERVER['DOCUMENT_ROOT'] as a constant, then use $path = DOCROOT . '/subdir1/yourdocument.txt'; – Luncheonette

Answer 5

The best way to do this given your setup is to define a constant describing the root path of your site. You can create a file config.php at the root of your application:

<?php

define('SITE_ROOT', dirname(__FILE__));

$file_path = SITE_ROOT . '/Texts/MyInfo.txt';

?>

Then include config.php in each entry point script and reference SITE_ROOT in your code rather than giving a relative path.

Tracay

After reading all these responses I am feeling like a noob. Anyway could you please give an example how can I use that SITE_ROOT in my .php file? Can I just simply write like this: SITE_ROOT . "Texts/Info.txt"?? – Erminiaerminie

Sure, once it's defined. But keep in mind dirname returns a path without a trailing slash, so you'll need to have a leading slash in any strings you concatenate to it: SITE_ROOT . "/Texts/Info.txt". – Tracay

The only problem I have found with this method is that you still need a relative path back to your config file, so you end up using relative paths anyway. – Trigg

Answer 6

use dirname(__FILE__) in a global configuration file.

Marikomaril

Or just DIR if you are using PHP >= 5.3 – Eley

Answer 7

The best way Using dirname(). Because SERVER['DOCUMENT_ROOT'] not working all servers, and also return server running path.

$root = dirname( __FILE__ );

$root = __DIR__;

$filePath = realpath(dirname(__FILE__));

$rootPath = realpath($_SERVER['DOCUMENT_ROOT']);

$htmlPath = str_replace($root, '', $filePath);

Borrell

Answer 8

This is my way to find the rootstart. Create at ROOT start a file with name mainpath.php

<?php 
## DEFINE ROOTPATH
$check_data_exist = ""; 

$i_surf = 0;

// looking for mainpath.php at the aktiv folder or higher folder

while (!file_exists($check_data_exist."mainpath.php")) {
  $check_data_exist .= "../"; 
  $i_surf++;
  // max 7 folder deep
  if ($i_surf == 7) { 
   return false;
  }
}

define("MAINPATH", ($check_data_exist ? $check_data_exist : "")); 
?>

For me is that the best and easiest way to find them. ^^

Brigittebriley