PHP cURL Redirect Tanpa Opsi FOLLOWLOCATION

Tidak seperti file_get_contents(), standarnya cURL di PHP tidak mengikuti redirect (pengalihan halaman). Harus mengaktifkan CURLOPT_FOLLOWLOCATION agar bisa mengikuti redirect. Namun tidak semua hosting menggunakan konfigurasi yang mengijinkan fitur ini. Seperti saat safe_mode atau open_basedir diaktifkan karena alasan keamanan. Untuk itu saya mencoba menulis fungsi berikut untuk mengatasi hal ini.

Berikut adalah fungsi untuk PHP >= 5.3.7 karena konstan CURLINFO_REDIRECT_URL tersedia sejak versi tersebut:

function curl_get_contents($url, $headers = array(), $maxredirs = 0) {

```
    static $ch, $redirscount = 0; 
```
```
    $ch or $ch = curl_init(); 
```

    curl_setopt($ch, CURLOPT_URL, $url);

    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

    curl_setopt($ch, CURLOPT_ENCODING, 'gzip, deflate');

    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

    curl_setopt($ch, CURLOPT_TIMEOUT, 10);

```
    $contents = curl_exec($ch); 
```

    $redir    = curl_getinfo($ch, CURLINFO_REDIRECT_URL);

    if ($redir && $redir != $url && ($maxredirs < 0 || $redirscount < $maxredirs)) {

```
        $redirscount++; 
```

        $headers['Referer'] = 'Referer: ' . $url;

        return curl_get_contents($redir, $headers, $maxredirs);

```
    } else { 
```
```
        curl_close($ch); 
```
```
        $ch = $redirscount = 0; 
```
```
        return $contents; 
```
```
    } 
```
```
} 
```

Berikut adalah fungsi kompatibel untuk PHP versi lama. Mungkin PHP >= 4.0.2. Namun hanya saya uji pada PHP 5.2.x:

function curl_get_contents_compat($url, $headers = array(), $maxredirs = 0) {

```
    static $ch, $redirscount = 0; 
```
```
    $ch or $ch = curl_init(); 
```

    curl_setopt($ch, CURLOPT_URL, $url);

    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

    curl_setopt($ch, CURLOPT_ENCODING, 'gzip, deflate');

    curl_setopt($ch, CURLOPT_HEADER, true);

    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

    curl_setopt($ch, CURLOPT_TIMEOUT, 10);

```
    $contents = curl_exec($ch); 
```
```
    $first    = true; 
```
```
    $redir    = $body = null; 
```

    $tok      = strtok($contents, "\n");

```
    while ($tok !== false) { 
```
```
        $tok = rtrim($tok); 
```
```
        if ($first && !$tok) { 
```
```
            $body  = null; 
```
```
            $first = false; 
```

        } elseif ($first && strpos($tok, 'Location: ') === 0) {

            $redir = str_replace('Location: ', null, $tok);

```
            $body  = null; 
```
```
            break; 
```
```
        } else { 
```
```
            $body .= $tok . "\n"; 
```
```
        } 
```
```
        $tok = strtok("\n"); 
```
```
    } 
```

    if ($redir && $redir != $url && ($maxredirs < 0 || $redirscount < $maxredirs)) {

```
        $redirscount++; 
```

        $headers['Referer'] = 'Referer: ' . $url;

        if (strpos($redir, '://') === false) { // relative url

            $path_pos = strpos($url, '/', 8);

```
            if ($redir[0] == '/') { 
```

                $redir = substr($url, 0, $path_pos) . $redir;

```
            } else { 
```

                $path = substr(strtok($url, '?'), $path_pos);

                $url  = substr($url, 0, $path_pos) . '/';

                if (strpos(basename($path), '.') === false) {

                    $url .= ltrim($path, '/');

```
                } else { 
```

                    $url .= ltrim(substr($path, 0, strrpos($path, '/')), '/');

```
                } 
```

                $redir = rtrim($url, '/') . '/' . $redir;

```
            } 
```
```
        } 
```

        return curl_get_contents_compat($redir, $headers, $maxredirs);

```
    } else { 
```
```
        curl_close($ch); 
```
```
        $ch = $redirscount = 0; 
```
```
        return $body; 
```
```
    } 
```
```
} 
```

Berikut adalah fungsi wrapper yang akan otomatis menyesuaikan:

function get_contents($url, $headers = array(), $maxredirs = 0) {

    return defined('CURLINFO_REDIRECT_URL') ? curl_get_contents($url, $headers, $maxredirs)

                                            : curl_get_contents_compat($url, $headers, $maxredirs);

```
} 
```

Penggunaan:
Argumen pertama adalah wajib. Sisanya opsional. $maxredirs standar nilainya -1, berarti redirect tak terbatas.

Contoh:

http://localhost/target.php

```
<?php 
```
```
 
```

header('Location: http://localhost/target1.php');

http://localhost/target1.php

```
<?php 
```
```
 
```

header('Location: http://localhost/target2.php');

http://localhost/target2.php

```
<?php 
```
```
 
```
```
phpinfo(); 
```

http://localhost/test.php

```
<?php 
```
```
 
```
```
// Paste tiga fungsi diatas ke sini 
```
```
 
```

echo get_contents('http://localhost/target.php');

Jika ingin membuat cURL benar-benar terdeteksi seperti browser tertentu, bisa menambahkan opsi $headers yang berupa array:

http://localhost/test.php

```
<?php 
```
```
 
```
```
// Paste tiga fungsi diatas ke sini 
```
```
 
```
```
$headers   = array(); 
```

$headers[] = 'User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0';

$headers[] = 'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8';

$headers[] = 'Accept-Language: en-US,en;q=0.5';

echo get_contents('http://localhost/target.php', $headers);

Selalu cek halaman ini karena selalu diperbaharui.

Update: Silahkan cek github saya: https://github.com/nggit/php-simple-client

1150 views 30 December 2017 at 10:01
Updated: 25 February 2019 at 13:08
Author: Administrator