Question

我知道我可以使用其他类，但我想使用LWP。这里接受的答案（How do I make parallel HTTP requests in Perl, and receive them back in order?）符合我的要求，但我需要“标记”线程，以便我可以将请求与响应相匹配。我已将代码修改为以下内容：

#Setup and query the DB:

#hold all response\id pairs
my @response_bundles; 
while (my @row = $query->fetchrow_array()) {
                my $id = $row[0];
                my $url = $row[1];

                push @threads, async {
                        my @container_hash;
                        $container_hash[0] = @row;
                        $container_hash[1] = $ua->get($url); 

                        push @response_bundles, @container_hash;
                };
}       

#Once this loop terminates all threads are done
for my $thread (@threads) {
                $thread->join;
}

#Since all threads are completed we can now sort through the response bundles
for my $response_bundle (@response_bundles) {
                print "test\n";
}

我的目标是启动一堆HTTP请求并将其（$ id，$ response）对存储在一个数组中。我将它们全部推入异步进程，async {}中的sub应该这样做（但事实并非如此）。我遍历线程数组，一旦完成，所有线程都应该完成。然后，我通过我的捆绑并做一些事情然而“打印测试”从未开始。我在考虑这个错误吗？

编辑：

根据评论我尝试返回值，但这不起作用

while (my @row = $query->fetchrow_array()) {
                my $id = $row[0];
                my $url = $row[1];

                push @threads, async {
                        my @container_hash;
                        $container_hash[0] = @row;
                        $container_hash[1] = $ua->get($url); 

                        return @container_hash;
                };
}       

#Once this loop terminates all threads are done
for my $thread (@threads) {
                my @container;
                @container = $thread->join;
                print $container[1];
}

Answer 1

您需要return线程中所需的数据，以便主程序可以处理它：

while (my @row = $query->fetchrow_array()) {
                my $id = $row[0];
                my $url = $row[1];

                push @threads, async {
                        my @container_hash;
                        $container_hash[0] = \@row; #I think you need this
                        $container_hash[1] = $ua->get($url); 

                        return \@container_hash; #and here we return reference to our data
                };
}       

#Once this loop terminates all threads are done
for my $thread (@threads) {

                my $container = $thread->join;
                print $container->[1], "\n"; #this is a reference that's why we use ->
}

Perl中的线程“标记”用于异步HTTP请求

1 个答案: