为什么 Perl 的 RabbitMQ 使用者会收到 404 错误？

Question

RabbitMQ 已设置，我可以使用示例脚本：

use Net::RabbitMQ;
my $mq = Net::RabbitMQ->new();
$mq->connect("localhost", { user => "guest", password => "guest" });
$mq->channel_open(1);
$mq->publish(1, "queuename", "Hi there!");
$mq->disconnect();

它发布消息（我假设）。我尝试了以下方法来简单地从队列中获取消息，但得到了 404：

my $mq = Net::RabbitMQ->new();
$mq->connect("localhost", { user => "guest", password => "guest" });
$mq->channel_open(1);
print $mq->get(1, "queuename");

Answer 1

错误消息全文为：

basic_get: server channel error 404, message: NOT_FOUND - no queue 'queuename' in vhost '/' ...

You need to create the queue with auto_delete =>; 0 - 否则当第一个进程终止时它将消失。看一下 queue_declare 方法。

Answer 2

我查看了 queue_declare 并将其添加到侦听器中，并更改了一些代码，如下所示：

#!/usr/bin/perl

use strict;
use Data::Dumper;
use Net::RabbitMQ;
my $channel = 1;
my $queue = "MyQueue.q";
my $exchange = "MyExchange.x";
my $routing_key = "foobar";
my $mq = Net::RabbitMQ->new();
$mq->connect("localhost", { user => "guest", password => "guest" });
$mq->channel_open($channel);
$mq->exchange_declare( $channel, $exchange, { auto_delete => 0, });
$mq->queue_declare( $channel, $queue, { auto_delete => 0, });
$mq->queue_bind( $channel, $queue, $exchange, $routing_key);

while(1){
    my $hashref = $mq->get($channel, $queue);
    next if (! defined($hashref));
    print Dumper($hashref);
}

我关闭侦听器脚本，然后，当我执行以下命令时，它会发布消息：

#!/usr/bin/perl
my $channel = 1;
my $queue = "MyQueue.q";
my $exchange = "MyExchange.x";
my $routing_key = "foobar";
use Net::RabbitMQ;
my $mq = Net::RabbitMQ->new();
$mq->connect("localhost", { user => "guest", password => "guest" });
$mq->channel_open(1);
$mq->publish($channel, $queue, "Message Here");
$mq->disconnect();