php parse_url reverse — parsed url

Question

Is there a way to reverse the url from a parsed url?

$url = 'http://www.domain.com/dir/index.php?query=blabla#more_bla';
$parse = parse_url($url);
print_r($parse);
/*
array(
 'scheme'=>'http://',
 etc....
)
*/
$revere = reverse_url($parse); // probably does not exist but u get the point

echo $reverse;
//outputs:// "http://www.domain.com/dir/index.php?query=blabla#more_bla"

Or if there is a way validate a url that is missing part of its recommended urls e.g

www.mydomain.com

mydomain.com

should all return http://www.mydomain.com or with correct sub domain

Answer 1

You should be able to do

http_build_url($parse)

NOTE: http_build_url is only available by installing pecl_http.

According to the docs it's designed specifically to handle the output from parse_url. Both functions handle anchors, query params, etc so there are no "other properties not mentioned on the $url".

To add http:// when it's missing, use a basic check before parsing it:

if (strpos($url, "http://") != 0)
    $url = "http://$url";

Answer 2

These are the two functions I use for decomposing and rebuilding URLs:

function http_parse_query($query) {
    $parameters = array();
    $queryParts = explode('&', $query);
    foreach ($queryParts as $queryPart) {
        $keyValue = explode('=', $queryPart, 2);
        $parameters[$keyValue[0]] = $keyValue[1];
    }
    return $parameters;
}

function build_url(array $parts) {
    return (isset($parts['scheme']) ? "{$parts['scheme']}:" : '') . 
        ((isset($parts['user']) || isset($parts['host'])) ? '//' : '') . 
        (isset($parts['user']) ? "{$parts['user']}" : '') . 
        (isset($parts['pass']) ? ":{$parts['pass']}" : '') . 
        (isset($parts['user']) ? '@' : '') . 
        (isset($parts['host']) ? "{$parts['host']}" : '') . 
        (isset($parts['port']) ? ":{$parts['port']}" : '') . 
        (isset($parts['path']) ? "{$parts['path']}" : '') . 
        (isset($parts['query']) ? "?{$parts['query']}" : '') . 
        (isset($parts['fragment']) ? "#{$parts['fragment']}" : '');
}

// Example
$parts = parse_url($url);

if (isset($parts['query'])) {
    $parameters = http_parse_query($parts['query']);
    foreach ($parameters as $key => $value) {
        $parameters[$key] = $value; // do stuff with $value
    }
    $parts['query'] = http_build_query($parameters);
}

$url = build_url($parts);

Answer 3

This function should do the trick:

/**
 * @param array $parsed
 * @return string
 */
function unparse_url(array $parsed) {
    $get = function ($key) use ($parsed) {
        return isset($parsed[$key]) ? $parsed[$key] : null;
    };

    $pass      = $get('pass');
    $user      = $get('user');
    $userinfo  = $pass !== null ? "$user:$pass" : $user;
    $port      = $get('port');
    $scheme    = $get('scheme');
    $query     = $get('query');
    $fragment  = $get('fragment');
    $authority =
        ($userinfo !== null ? "$userinfo@" : '') .
        $get('host') .
        ($port ? ":$port" : '');

    return
        (strlen($scheme) ? "$scheme:" : '') .
        (strlen($authority) ? "//$authority" : '') .
        $get('path') .
        (strlen($query) ? "?$query" : '') .
        (strlen($fragment) ? "#$fragment" : '');
}

Here is a short test for it:

function unparse_url_test() {
    foreach ([
        '',
        'foo',
        'http://www.google.com/',
        'http://u:p@foo:1/path/path?q#frag',
        'http://u:p@foo:1/path/path?#',
        'ssh://root@host',
        '://:@:1/?#',
        'http://:@foo:1/path/path?#',
        'http://@foo:1/path/path?#',
    ] as $url) {
        $parsed1 = parse_url($url);
        $parsed2 = parse_url(unparse_url($parsed1));

        if ($parsed1 !== $parsed2) {
            print var_export($parsed1, true) . "\n!==\n" . var_export($parsed2, true) . "\n\n";
        }
    }
}

unparse_url_test();

Answer 4

Another implemention:

function build_url(array $elements) {
    $e = $elements;
    return
        (isset($e['host']) ? (
            (isset($e['scheme']) ? "$e[scheme]://" : '//') .
            (isset($e['user']) ? $e['user'] . (isset($e['pass']) ? ":$e[pass]" : '') . '@' : '') .
            $e['host'] .
            (isset($e['port']) ? ":$e[port]" : '')
        ) : '') .
        (isset($e['path']) ? $e['path'] : '/') .
        (isset($e['query']) ? '?' . (is_array($e['query']) ? http_build_query($e['query'], '', '&') : $e['query']) : '') .
        (isset($e['fragment']) ? "#$e[fragment]" : '')
    ;
}

The results should be:

{
    "host": "example.com"
}
/* //example.com/ */

{
    "scheme": "https",
    "host": "example.com"
}
/* https://example.com/ */

{
    "scheme": "http",
    "host": "example.com",
    "port": 8080,
    "path": "/x/y/z"
}
/* http://example.com:8080/x/y/z */

{
    "scheme": "http",
    "host": "example.com",
    "port": 8080,
    "user": "anonymous",
    "query": "a=b&c=d",
    "fragment": "xyz"
}
/* http://anonymous@example.com:8080/?a=b&c=d#xyz */

{
    "scheme": "http",
    "host": "example.com",
    "user": "root",
    "pass": "stupid",
    "path": "/x/y/z",
    "query": {
        "a": "b",
        "c": "d"
    }
}
/* http://root:stupid@example.com/x/y/z?a=b&c=d */

{
    "path": "/x/y/z",
    "query": "a=b&c=d"
}
/* /x/y/z?a=b&c=d */

Answer 5

Get last string from url eg: http://example.com/controllername/functionname and need to get functionname

$referer = explode('/',strrev($_SERVER['HTTP_REFERER']));

$lastString = strrev($referer[0]);