Mojolicious 数据库插件 - 帮助程序错误

Question

我正在尝试使用Mojolicious database plugin，发现了一些困难。我已经访问了关于此主题的前两页 Google 结果。场景非常简单：连接到数据库 (mysql)，获取一些数据，显示它。这是代码的摘录：

use Mojolicious::Lite;
use Mojolicious::Plugin::Database;

# [...]

sub startup {
    my $self = shift;
    $self->plugin('database', {
            dsn      => 'dbi:MySQL:dbname=y',
            username => $mysql_user,
            password => $mysql_passwd,
            helper   => 'ydb',
            });
};

get '/' => sub {
    my $c = shift;
    my $zz=$c->ydb->prepare("select count(*) from customers");
    my $total=$zz->execute();                                 
    $c->ydb->bind_columns($total);
    $c->ydb->fetch;
    $c->session(customer=>$total);
    $c->render(template => 'index');
};

但我收到错误消息：

Can't locate object method "ydb" via package "Mojolicious::Controller"

我肯定缺少一些基础知识。有人能给我指出正确的方向吗？

Answer 1

我从来没有让插件的助手工作。我结合 Mojo::mysql.

创建了自己的助手

use Mojolicious::Lite;
use Mojo::mysql;

sub startup {
    my $self = shift;
}

helper ydb => sub {
        my $c = shift ;
        return Mojo::mysql->strict_mode('mysql://muziek:muziek@localhost/muziek') 
};

get '/foo' => sub {
  my $c = shift ;

  my $db = $c->ydb->db;
  my $row = $db->query("select count(*) COUNT from TITLE")->hash;
  $c->render(text => "Hello from /foo. count="  . $row->{COUNT} );
};

app->start;

Mojolicious 数据库插件 - 帮助程序错误

Mojolicious database plugin - helper error

mysql

mojolicious-lite