httpClient or Guzzle and Complex or nested query arrays.

Introduction

With the addition of Guzzle HTTP client library added to replace drupal_http_request().

An interesting issue has came up in regards to multidimensional associative arrays being passed to Guzzle as the query parameters.

In Drupal 7

$url = 'http://example.com';

$query = array(
  'user' => array(
    'name' => 'Bob Smith',
    'age'=>47,
  ),
);

drupal_http_request($url, array('query' => $query));

In Drupal 8

$url = 'http://example.com';

$query = array(
  'user' => array(
    'name' => 'Bob Smith',
    'age'=>47,
  ),
);

$client = \Drupal::httpClient();
$request = $client->get($url, array(), $query);
$response = json_decode($request->getBody(), true);

The above will fail.

Solution

The only work around I have is appending the parsed parameters onto the end of the url.

$url = 'http://example.com';

$query = array(
  'user' => array(
    'name' => 'Bob Smith',
    'age'=>47,
  ),
);

$query_str = UrlHelper::buildQuery($query);

$url = $url . '?' . $query_str;

$client = \Drupal::httpClient();
$request = $client->get($url);
$response = json_decode($request->getBody(), true);

The above we are using the UrlHelper that has replaced drupal_http_build_query: URL related functions got moved to a new UrlHelper component. Many of those url helpers were used in drupal_http_request().

https://github.com/guzzle/guzzle/issues/90 > https://github.com/ioseb/uri-template/issues/2

Issue

The use of drupal_http_request is used a lot of places in drupal 7. Views using this functionality a lot for example with multiple taxonomy terms filtering a view. Work around is ugly so documentation is needed.

Hopefully this helps someone, somewhere, some day.