Proyectos de Subversion Moodle

Rev

| Ultima modificación | Ver Log |

Rev Autor Línea Nro. Línea
1 efrain 1 
<?php
2 
 
3 
namespace GuzzleHttp;
4 
 
5 
use GuzzleHttp\Promise as P;
6 
use GuzzleHttp\Promise\PromiseInterface;
7 
use Psr\Http\Message\RequestInterface;
8 
use Psr\Http\Message\ResponseInterface;
9 
 
10 
/**
11 
 * Middleware that retries requests based on the boolean result of
12 
 * invoking the provided "decider" function.
13 
 *
14 
 * @final
15 
 */
16 
class RetryMiddleware
17 
{
18 
    /**
19 
     * @var callable(RequestInterface, array): PromiseInterface
20 
     */
21 
    private $nextHandler;
22 
 
23 
    /**
24 
     * @var callable
25 
     */
26 
    private $decider;
27 
 
28 
    /**
29 
     * @var callable(int)
30 
     */
31 
    private $delay;
32 
 
33 
    /**
34 
     * @param callable                                            $decider     Function that accepts the number of retries,
35 
     *                                                                         a request, [response], and [exception] and
36 
     *                                                                         returns true if the request is to be
37 
     *                                                                         retried.
38 
     * @param callable(RequestInterface, array): PromiseInterface $nextHandler Next handler to invoke.
39 
     * @param (callable(int): int)|null                           $delay       Function that accepts the number of retries
40 
     *                                                                         and returns the number of
41 
     *                                                                         milliseconds to delay.
42 
     */
43 
    public function __construct(callable $decider, callable $nextHandler, callable $delay = null)
44 
    {
45 
        $this->decider = $decider;
46 
        $this->nextHandler = $nextHandler;
47 
        $this->delay = $delay ?: __CLASS__ . '::exponentialDelay';
48 
    }
49 
 
50 
    /**
51 
     * Default exponential backoff delay function.
52 
     *
53 
     * @return int milliseconds.
54 
     */
55 
    public static function exponentialDelay(int $retries): int
56 
    {
57 
        return (int) \pow(2, $retries - 1) * 1000;
58 
    }
59 
 
60 
    public function __invoke(RequestInterface $request, array $options): PromiseInterface
61 
    {
62 
        if (!isset($options['retries'])) {
63 
            $options['retries'] = 0;
64 
        }
65 
 
66 
        $fn = $this->nextHandler;
67 
        return $fn($request, $options)
68 
            ->then(
69 
                $this->onFulfilled($request, $options),
70 
                $this->onRejected($request, $options)
71 
            );
72 
    }
73 
 
74 
    /**
75 
     * Execute fulfilled closure
76 
     */
77 
    private function onFulfilled(RequestInterface $request, array $options): callable
78 
    {
79 
        return function ($value) use ($request, $options) {
80 
            if (!($this->decider)(
81 
                $options['retries'],
82 
                $request,
83 
                $value,
84 
                null
85 
            )) {
86 
                return $value;
87 
            }
88 
            return $this->doRetry($request, $options, $value);
89 
        };
90 
    }
91 
 
92 
    /**
93 
     * Execute rejected closure
94 
     */
95 
    private function onRejected(RequestInterface $req, array $options): callable
96 
    {
97 
        return function ($reason) use ($req, $options) {
98 
            if (!($this->decider)(
99 
                $options['retries'],
100 
                $req,
101 
                null,
102 
                $reason
103 
            )) {
104 
                return P\Create::rejectionFor($reason);
105 
            }
106 
            return $this->doRetry($req, $options);
107 
        };
108 
    }
109 
 
110 
    private function doRetry(RequestInterface $request, array $options, ResponseInterface $response = null): PromiseInterface
111 
    {
112 
        $options['delay'] = ($this->delay)(++$options['retries'], $response, $request);
113 
 
114 
        return $this($request, $options);
115 
    }
116 
}