Drupal - What is the equivalent of a call to drupal_http_request()?

Finally i find a code in https://api.drupal.org/api/drupal/core%21includes%21install.core.inc/8 (1375)

and its working for me :)

 try {
    $response = \Drupal::httpClient()->get($uri, array('headers' => array('Accept' => 'text/plain')));
    $data = (string) $response->getBody();
    if (empty($data)) {
      return FALSE;
    }
  }
  catch (RequestException $e) {
    return FALSE;
  }

Hope this will help for some one

HTTP client library added to replace drupal_http_request()

$client = \Drupal::httpClient();
$request = $client->createRequest('GET', $feed->url);
$request->addHeader('If-Modified-Since', gmdate(DATE_RFC1123, $last_fetched));

try {
  $response = $client->get($feed->uri, [
    'headers' => [
      'If-Modified-Since' => gmdate(DATE_RFC1123, $last_fetched),
    ],
  ]);
  // Expected result.
  // getBody() returns an instance of Psr\Http\Message\StreamInterface.
  // @see http://docs.guzzlephp.org/en/latest/psr7.html#body
  $data = $response->getBody();
}
catch (RequestException $e) {
  watchdog_exception('my_module', $e);
}