<?php
namespace GuzzleHttp;
use GuzzleHttp\Exception\BadResponseException;
use GuzzleHttp\Exception\TooManyRedirectsException;
use GuzzleHttp\Promise\PromiseInterface;
use GuzzleHttp\Psr7;
use Psr\Http\Message\RequestInterface;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\UriInterface;
/**
* Request redirect middleware.
*
* Apply this middleware like other middleware using
* {@see GuzzleHttp\Middleware::redirect()}.
*/
class RedirectMiddleware
{
const HISTORY_HEADER = 'X-Guzzle-Redirect-History';
const STATUS_HISTORY_HEADER = 'X-Guzzle-Redirect-Status-History';
public static $defaultSettings = [
'max' => 5,
'protocols' => ['http', 'https'],
'strict' => false,
'referer' => false,
'track_redirects' => false,
];
/** @var callable */
private $nextHandler;
/**
* @param callable $nextHandler Next handler to invoke.
*/
public function __construct(callable $nextHandler)
{
$this->nextHandler = $nextHandler;
}
/**
* @param RequestInterface $request
* @param array $options
*
* @return PromiseInterface
*/
public function __invoke(RequestInterface $request, array $options)
{
$fn = $this->nextHandler;
if (empty($options['allow_redirects'])) {
return $fn($request, $options);
}
if ($options['allow_redirects'] === true) {
$options['allow_redirects'] = self::$defaultSettings;
} elseif (!is_array($options['allow_redirects'])) {
throw new \InvalidArgumentException('allow_redirects must be true, false, or array');
} else {
// Merge the default settings with the provided settings
$options['allow_redirects'] += self::$defaultSettings;
}
if (empty($options['allow_redirects']['max'])) {
return $fn($request, $options);
}
return $fn($request, $options)
->then(function (ResponseInterface $response) use ($request, $options) {
return $this->checkRedirect($request, $options, $response);
});
}
/**
* @param RequestInterface $request
* @param array $options
* @param ResponseInterface|PromiseInterface $response
*
* @return ResponseInterface|PromiseInterface
*/
public function checkRedirect(
RequestInterface $request,
array $options,
ResponseInterface $response
) {
if (substr($response->getStatusCode(), 0, 1) != '3'
|| !$response->hasHeader('Location')
) {
return $response;
}
$this->guardMax($request, $options);
$nextRequest = $this->modifyRequest($request, $options, $response);
if (isset($options['allow_redirects']['on_redirect'])) {
call_user_func(
$options['allow_redirects']['on_redirect'],
$request,
$response,
$nextRequest->getUri()
);
}
/** @var PromiseInterface|ResponseInterface $promise */
$promise = $this($nextRequest, $options);
// Add headers to be able to track history of redirects.
if (!empty($options['allow_redirects']['track_redirects'])) {
return $this->withTracking(
$promise,
(string) $nextRequest->getUri(),
$response->getStatusCode()
);
}
return $promise;
}
private function withTracking(PromiseInterface $promise, $uri, $statusCode)
{
return $promise->then(
function (ResponseInterface $response) use ($uri, $statusCode) {
// Note that we are pushing to the front of the list as this
// would be an earlier response than what is currently present
// in the history header.
$historyHeader = $response->getHeader(self::HISTORY_HEADER);
$statusHeader = $response->getHeader(self::STATUS_HISTORY_HEADER);
array_unshift($historyHeader, $uri);
array_unshift($statusHeader, $statusCode);
return $response->withHeader(self::HISTORY_HEADER, $historyHeader)
->withHeader(self::STATUS_HISTORY_HEADER, $statusHeader);
}
);
}
private function guardMax(RequestInterface $request, array &$options)
{
$current = isset($options['__redirect_count'])
? $options['__redirect_count']
: 0;
$options['__redirect_count'] = $current + 1;
$max = $options['allow_redirects']['max'];
if ($options['__redirect_count'] > $max) {
throw new TooManyRedirectsException(
"Will not follow more than {$max} redirects",
$request
);
}
}
/**
* @param RequestInterface $request
* @param array $options
* @param ResponseInterface $response
*
* @return RequestInterface
*/
public function modifyRequest(
RequestInterface $request,
array $options,
ResponseInterface $response
) {
// Request modifications to apply.
$modify = [];
$protocols = $options['allow_redirects']['protocols'];
// Use a GET request if this is an entity enclosing request and we are
// not forcing RFC compliance, but rather emulating what all browsers
// would do.
$statusCode = $response->getStatusCode();
if ($statusCode == 303 ||
($statusCode <= 302 && $request->getBody() && !$options['allow_redirects']['strict'])
) {
$modify['method'] = 'GET';
$modify['body'] = '';
}
$modify['uri'] = $this->redirectUri($request, $response, $protocols);
Psr7\rewind_body($request);
// Add the Referer header if it is told to do so and only
// add the header if we are not redirecting from https to http.
if ($options['allow_redirects']['referer']
&& $modify['uri']->getScheme() === $request->getUri()->getScheme()
) {
$uri = $request->getUri()->withUserInfo('', '');
$modify['set_headers']['Referer'] = (string) $uri;
} else {
$modify['remove_headers'][] = 'Referer';
}
// Remove Authorization header if host is different.
if ($request->getUri()->getHost() !== $modify['uri']->getHost()) {
$modify['remove_headers'][] = 'Authorization';
}
return Psr7\modify_request($request, $modify);
}
/**
* Set the appropriate URL on the request based on the location header
*
* @param RequestInterface $request
* @param ResponseInterface $response
* @param array $protocols
*
* @return UriInterface
*/
private function redirectUri(
RequestInterface $request,
ResponseInterface $response,
array $protocols
) {
$location = Psr7\UriResolver::resolve(
$request->getUri(),
new Psr7\Uri($response->getHeaderLine('Location'))
);
// Ensure that the redirect URI is allowed based on the protocols.
if (!in_array($location->getScheme(), $protocols)) {
throw new BadResponseException(
sprintf(
'Redirect URI, %s, does not use one of the allowed redirect protocols: %s',
$location,
implode(', ', $protocols)
),
$request,
$response
);
}
return $location;
}
}