| 
<?phpnamespace GuzzleHttp;
 
 use GuzzleHttp\Cookie\CookieJarInterface;
 use GuzzleHttp\Exception\RequestException;
 use GuzzleHttp\Promise\RejectedPromise;
 use GuzzleHttp\Psr7;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Log\LoggerInterface;
 use Psr\Log\LogLevel;
 
 /**
 * Functions used to create and wrap handlers with handler middleware.
 */
 final class Middleware
 {
 /**
 * Middleware that adds cookies to requests.
 *
 * The options array must be set to a CookieJarInterface in order to use
 * cookies. This is typically handled for you by a client.
 *
 * @return callable Returns a function that accepts the next handler.
 */
 public static function cookies()
 {
 return function (callable $handler) {
 return function ($request, array $options) use ($handler) {
 if (empty($options['cookies'])) {
 return $handler($request, $options);
 } elseif (!($options['cookies'] instanceof CookieJarInterface)) {
 throw new \InvalidArgumentException('cookies must be an instance of GuzzleHttp\Cookie\CookieJarInterface');
 }
 $cookieJar = $options['cookies'];
 $request = $cookieJar->withCookieHeader($request);
 return $handler($request, $options)
 ->then(function ($response) use ($cookieJar, $request) {
 $cookieJar->extractCookies($request, $response);
 return $response;
 }
 );
 };
 };
 }
 
 /**
 * Middleware that throws exceptions for 4xx or 5xx responses when the
 * "http_error" request option is set to true.
 *
 * @return callable Returns a function that accepts the next handler.
 */
 public static function httpErrors()
 {
 return function (callable $handler) {
 return function ($request, array $options) use ($handler) {
 if (empty($options['http_errors'])) {
 return $handler($request, $options);
 }
 return $handler($request, $options)->then(
 function (ResponseInterface $response) use ($request, $handler) {
 $code = $response->getStatusCode();
 if ($code < 400) {
 return $response;
 }
 throw RequestException::create($request, $response);
 }
 );
 };
 };
 }
 
 /**
 * Middleware that pushes history data to an ArrayAccess container.
 *
 * @param array $container Container to hold the history (by reference).
 *
 * @return callable Returns a function that accepts the next handler.
 */
 public static function history(array &$container)
 {
 return function (callable $handler) use (&$container) {
 return function ($request, array $options) use ($handler, &$container) {
 return $handler($request, $options)->then(
 function ($value) use ($request, &$container, $options) {
 $container[] = [
 'request'  => $request,
 'response' => $value,
 'error'    => null,
 'options'  => $options
 ];
 return $value;
 },
 function ($reason) use ($request, &$container, $options) {
 $container[] = [
 'request'  => $request,
 'response' => null,
 'error'    => $reason,
 'options'  => $options
 ];
 return new RejectedPromise($reason);
 }
 );
 };
 };
 }
 
 /**
 * Middleware that invokes a callback before and after sending a request.
 *
 * The provided listener cannot modify or alter the response. It simply
 * "taps" into the chain to be notified before returning the promise. The
 * before listener accepts a request and options array, and the after
 * listener accepts a request, options array, and response promise.
 *
 * @param callable $before Function to invoke before forwarding the request.
 * @param callable $after  Function invoked after forwarding.
 *
 * @return callable Returns a function that accepts the next handler.
 */
 public static function tap(callable $before = null, callable $after = null)
 {
 return function (callable $handler) use ($before, $after) {
 return function ($request, array $options) use ($handler, $before, $after) {
 if ($before) {
 $before($request, $options);
 }
 $response = $handler($request, $options);
 if ($after) {
 $after($request, $options, $response);
 }
 return $response;
 };
 };
 }
 
 /**
 * Middleware that handles request redirects.
 *
 * @return callable Returns a function that accepts the next handler.
 */
 public static function redirect()
 {
 return function (callable $handler) {
 return new RedirectMiddleware($handler);
 };
 }
 
 /**
 * Middleware that retries requests based on the boolean result of
 * invoking the provided "decider" function.
 *
 * If no delay function is provided, a simple implementation of exponential
 * backoff will be utilized.
 *
 * @param callable $decider Function that accepts the number of retries,
 *                          a request, [response], and [exception] and
 *                          returns true if the request is to be retried.
 * @param callable $delay   Function that accepts the number of retries and
 *                          returns the number of milliseconds to delay.
 *
 * @return callable Returns a function that accepts the next handler.
 */
 public static function retry(callable $decider, callable $delay = null)
 {
 return function (callable $handler) use ($decider, $delay) {
 return new RetryMiddleware($decider, $handler, $delay);
 };
 }
 
 /**
 * Middleware that logs requests, responses, and errors using a message
 * formatter.
 *
 * @param LoggerInterface  $logger Logs messages.
 * @param MessageFormatter $formatter Formatter used to create message strings.
 * @param string           $logLevel Level at which to log requests.
 *
 * @return callable Returns a function that accepts the next handler.
 */
 public static function log(LoggerInterface $logger, MessageFormatter $formatter, $logLevel = LogLevel::INFO)
 {
 return function (callable $handler) use ($logger, $formatter, $logLevel) {
 return function ($request, array $options) use ($handler, $logger, $formatter, $logLevel) {
 return $handler($request, $options)->then(
 function ($response) use ($logger, $request, $formatter, $logLevel) {
 $message = $formatter->format($request, $response);
 $logger->log($logLevel, $message);
 return $response;
 },
 function ($reason) use ($logger, $request, $formatter) {
 $response = $reason instanceof RequestException
 ? $reason->getResponse()
 : null;
 $message = $formatter->format($request, $response, $reason);
 $logger->notice($message);
 return \GuzzleHttp\Promise\rejection_for($reason);
 }
 );
 };
 };
 }
 
 /**
 * This middleware adds a default content-type if possible, a default
 * content-length or transfer-encoding header, and the expect header.
 *
 * @return callable
 */
 public static function prepareBody()
 {
 return function (callable $handler) {
 return new PrepareBodyMiddleware($handler);
 };
 }
 
 /**
 * Middleware that applies a map function to the request before passing to
 * the next handler.
 *
 * @param callable $fn Function that accepts a RequestInterface and returns
 *                     a RequestInterface.
 * @return callable
 */
 public static function mapRequest(callable $fn)
 {
 return function (callable $handler) use ($fn) {
 return function ($request, array $options) use ($handler, $fn) {
 return $handler($fn($request), $options);
 };
 };
 }
 
 /**
 * Middleware that applies a map function to the resolved promise's
 * response.
 *
 * @param callable $fn Function that accepts a ResponseInterface and
 *                     returns a ResponseInterface.
 * @return callable
 */
 public static function mapResponse(callable $fn)
 {
 return function (callable $handler) use ($fn) {
 return function ($request, array $options) use ($handler, $fn) {
 return $handler($request, $options)->then($fn);
 };
 };
 }
 }
 
 |