在一个Mojolicous的完整应用程序中，我有一个模型帮助器，它返回一个哈希值。我想定期更新这个哈希的内容（从下载的CSV）。

我的问题：如何使users成为状态变量（和/或使用Mojo::Base has？）这样我就不会每次通话时都从文件中读取？也就是说，在调用update、delete的过程中，users哈希值并重新创建它，如果下载成功？

我举了一个Lite示例来演示我想要实现的目标：

• GET /update-下载更新的CSV，并将其存储为${epoch}.json（如果下载成功，我需要它来更新哈希值）
• GET /-通过阅读最新的${epoch}.json文件并返回所需的散列来列出用户。（这应该只返回哈希值，而不是每次调用时读取文件。

use Mojolicious::Lite -signatures;

helper users => sub($self) {
    my $users;
    my $newest;
    foreach my $filename (sort {$b cmp $a} glob("1*.csv")) {
        $newest = $filename;
        last;
    }
    open my $fh, "<:encoding(utf8)", $newest or die $!;
    while (<$fh>) {
        next if $. == 1; # ignore CSV header
        my ($name,$email,$phone) = split(',');
        $users->{$email} = $name;
    }
    close($fh);
    $users;
};

helper update => sub ($self) {
    my $tx = $self->ua->get( 'https://test-backend.lambdatest.com/api/dev-tools/csv-generator' );
    my $res = eval { $tx->result };
    return $@ if $@;
    my $epoch = Mojo::Date->new()->epoch;
    Mojo::File->new( "${epoch}.csv" )->spurt( $res->text );
    return 'ok';
};

get '/' => sub ($self) {
    my @names = sort values %{ $self->users };
    $self->render(json => {emails=>[@names]} );
    
};

get '/update' => sub ($self) {
    $self->render(text => $self->update );
};

app->start;

字符串
在我的完整应用程序中，我的代码看起来像：

$self->helper(users => sub {state $data = MyApp::Model::Users->new(app => $self)});

型
然后在Users.pm中：

package MyApp::Model::Users;
use Mojo::Base -base, -signatures;
use Text::CSV_XS;

has 'app';
has 'users' => sub($self) {
  my $users;
    open my $fh, "<:encoding(utf8)", $self->app->config->{'filename'} or die $!;
    my $csv = Text::CSV_XS->new ({ diag_verbose=>1, auto_diag=>1, binary=>1, sep_char=>";" });
    $csv->getline($fh); # Ignore Header
    while (my $row = $csv->getline ($fh)) {        
        $users->{ $row->[0] } = $row->[1];
    }
    close($fh);
    $users;
};

型
我对这段代码的问题是，我不知道如何在初始设置后更新users。

编辑

我知道如何在一个完整的应用程序中实现它，但我不知道如何访问$self->users。在一个完整的应用程序中，我会这样做：$self->helper(users => sub {state $data = MyApp::Model::Users->new(app => $self)});

use Mojolicious::Lite -base, -signatures;

has 'users' => sub($self) {
    my $users = {};
    my $newest;
    foreach my $filename (sort {$b cmp $a} glob("1*.csv")) {
        $newest = $filename;
        last;
    }
    $self->updateUsers($newest, $users);
    $users;
};

helper updateUsers => sub($self, $filename, $users=undef) {
    say STDERR "### updateUsers($filename)";
    $users //= $self->users;
    delete @$users{keys %$users}; # delete existing hash
    open my $fh, "<:encoding(utf8)", $filename or die $!;
    while (<$fh>) {
        next if $. == 1; # ignore CSV header
        my ($name,$email,$phone) = split(',');
        $users->{$email} = $name;
    }
    close($fh);
    $users;
};

helper update => sub ($self) {
    my $tx = $self->ua->get( 'https://test-backend.lambdatest.com/api/dev-tools/csv-generator' );
    my $res = eval { $tx->result };
    return $@ if $@;
    my $epoch = Mojo::Date->new()->epoch;
    my $file = Mojo::File->new( "${epoch}.csv" )->spurt( $res->text );
    $self->update( $file->to_string );    
    return 'ok';
};

get '/' => sub ($self) {
    my @names = sort values %{ $self->users };
    $self->render(json => {emails=>[@names]} );
    
};

get '/update' => sub ($self) {
    $self->render(text => $self->update );
};

app->start;

型