Category: PHP

What PHP functions file_exists, is_file, is_dir and is_link return for file, directory, hard link and soft link?

<?php

/*
touch file
mkdir dir
ln file file_hard_link
ln -s file file_soft_link
ln -s dir dir_soft_link
touch dir/file_in_dir
echo 1 > file
cat file file_hard_link file_soft_link
*/

$tests = [
    'file',
    'dir',
    'file_hard_link',
    'file_soft_link',
    'dir_soft_link',
    'dir/file_in_dir',
    'dir_soft_link/file_in_dir'
];

foreach ($tests as $test) {
    echo 'name: ', str_pad($test, 25) . ' ';
    echo 'file_exists: ', (int)file_exists($test) . ' ';
    echo 'is_file: ', (int)is_file($test)  . ' ';
    echo 'is_dir: ', (int)is_dir($test) . ' ';
    echo 'is_link: ', (int)is_link($test) . PHP_EOL;
}

Result:

name: file                      file_exists: 1 is_file: 1 is_dir: 0 is_link: 0
name: dir                       file_exists: 1 is_file: 0 is_dir: 1 is_link: 0
name: file_hard_link            file_exists: 1 is_file: 1 is_dir: 0 is_link: 0
name: file_soft_link            file_exists: 1 is_file: 1 is_dir: 0 is_link: 1
name: dir_soft_link             file_exists: 1 is_file: 0 is_dir: 1 is_link: 1
name: dir/file_in_dir           file_exists: 1 is_file: 1 is_dir: 0 is_link: 0
name: dir_soft_link/file_in_dir file_exists: 1 is_file: 1 is_dir: 0 is_link: 0

Simple function to convert numbers from SI notation to float:
– decimal point separator – dot or comma
– thousands separator – space

In this case used to load money value from strings in different formats.

Examples:
##
# ###
# ###, #
# ###.#
#,###
12 -> 12
1 234 -> 1234
1 234,5 -> 1234.5
1 234.5 -> 1234.5
1,234 -> 1.234

<?php
$validTests = [
    '1 234',
    '-1 234',
    '- 1 234',
    '1 234.00',
    '-1 234.00',
    '1 234,00',
    '-1 234,00',
    '1234',
    '-1234',
    '1234.00',
    '-1234.00',
    '1234,00',
    '-1234,00',
    '1 234,00000000000',
    '1234,00000000000',
    '1 234,34545654565',
    '-1 234,34545654565',
    '1234,34545654565',
    '-1234,34545654565',
    '1 234 567',
    '1 234 567.00343',
    '1 234 567,34565',
    '1.234',
];

$invalidTests = [
    '-1 $',
    '1,234.00',
    '1.234,00',
    '-1.234,00',
    '-1.234.567',
    '-1.234.567,00',
    '-1,234,567.00',
];

function getAmountValue($money)
{
    $value = trim($money);
    $value = str_replace(' ', '', $value);

    $invalidCharacters = preg_replace('/([0-9\.,-])/i', '', $value);
    if (!empty($invalidCharacters)) {
        throw new InvalidArgumentException('Money value string "' . $value . '" contains invalid characters: "' . $invalidCharacters . '"!');
    }

    $separatorsCount = mb_substr_count($value, '.') + mb_substr_count($value, ',');
    if ($separatorsCount > 1) {
        throw new InvalidArgumentException('Money value string "' . $value . '" contains more than 1 separator!');
    }
    $value = str_replace(',', '.', $value);

    return (float)$value;
}

foreach ($validTests as $money) {
    try {
        $value = getAmountValue($money);
    } catch (Exception $exception) {
        $value = $exception->getMessage();
    }
    echo var_export($money, true) . ' = ' . var_export($value, true) . PHP_EOL;
}

echo '--- INVALID ---' . PHP_EOL;

foreach ($invalidTests as $money) {
    try {
        $value = getAmountValue($money);
    } catch (Exception $exception) {
        $value = $exception->getMessage();
    }
    echo var_export($money, true) . ' = ' . var_export($value, true) . PHP_EOL;
}

Apache .htaccess (redirect all requests to not existing files/directories to index.php):

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.+)$ index.php [QSA,L]

PHP router file. Check if route is on list of available routes and include file by name of route. Some parts of route can be variables: ‘user/$name’. Variables can have default values: ‘users/$order=id’, default value can be empty string: ‘user/$name=’

<?php
var_dump((string)$_SERVER['REDIRECT_URL']);
$urlParts = explode('/', trim((string)$_SERVER['REDIRECT_URL'], '/'));

$routes = [
    'login',
    'logout',
    'user/$name',
    'users/list/$type=level/$page=2/$vocation=all',
];

function openRoute($pathParts, $vars)
{
    $file = 'pages/' . implode('_', $pathParts) . '.php';

    ob_start();
    extract($vars);
    $main_content = '';
    include($file);
    $main_content .= ob_get_clean();

    return $main_content;
}

$routeFound = false;

foreach ($routes as $route) {
    $routeParts = explode('/', $route);
    $vars = [];
    $pathParts = [];

    if (count($routeParts) >= count($urlParts)) {
        foreach ($routeParts as $partId => $routePart) {
            if ($routePart[0] === '$') {
                $optionalVar = strpos($routePart, '=') !== false;

                if ($optionalVar) {
                    list($varName, $defaultValue) = explode('=', $routePart);
                    $varName = substr($varName, 1);
                } else {
                    $varName = substr($routePart, 1);
                }

                if (isset($urlParts[$partId])) {
                    $vars[$varName] = $urlParts[$partId];
                } elseif ($optionalVar) {
                    $vars[$varName] = $defaultValue;
                } else {
                    continue 2;
                }
            } elseif (isset($urlParts[$partId]) && $routePart === $urlParts[$partId]) {
                $pathParts[] = $routePart;
            } else {
                continue 2;
            }
        }

        var_dump('found: ', $route, $vars, $pathParts);
        $main_content = openRoute($pathParts, $vars);
        $routeFound = true;

        break;
    }
}

if (!$routeFound) {
    http_response_code(404);
    echo '404 Not found';
    exit;
}