perl - 如何取消来自 Mojo::UserAgent 的正在进行的请求？

Question

假设我想取消一个正在运行的请求 Mojo::UserAgent ？我该怎么做？

Answer 1

演示如何取消 promise

在此示例中，我们创建了一个随机 Timer promise 和一个 HTTP Get promise 。第一个获胜的rejects另一个 promise 。

use Mojo::UserAgent;
use v5.30;
use experimental 'signatures';

my $ua = Mojo::UserAgent->new;
my $p1 = Mojo::Promise->timer(rand('0.4') , 'Timeout');
my $p2 = $ua->get_p('https://www.cpanel.net/is_hiring_message_evan_carroll_on_linkedin');

$p1
  ->then(sub ($res) {$p2->reject("\t> reject \$p2"); say $res})
  ->catch(sub ($msg) {say $msg});
$p2
  ->then(sub ($res) {$p1->reject("\t> reject \$p1"); say $res})
  ->catch(sub ($msg) {say $msg});

Mojo::Promise->new->all( $p1, $p2 )->catch(sub{})->wait;

请注意，如果超时成功，您可能会收到一个错误事件，因为 Premature connection close 这正是您所期望的。你可以在这里看到我们正在使用 Mojo::Promise's all ,

Returns a new Mojo::Promise object that either fulfills when all of the passed Mojo::Promise objects have fulfilled or rejects as soon as one of them rejects. If the returned promise fulfills, it is fulfilled with the values from the fulfilled promises in the same order as the passed promises.

请注意，在本例中为 race可能更适用。我们不必手动拒绝其他 promise ，但我想通过手动 reject 来抽象地演示拒绝。