$self->ua vs. Mojo::UserAgent->new

[hussam-qasem]

I'm stating to fall in love with everything Mojolicious. I am converting an old application which uses:

• SOAP::Lite
• REST::Client
• WWW::Mechanize

and I find Mojo::UserAgent is nearly a direct replacement for REST::Client and not-so-complex WWW::Mechanize use cases. Would you agree?

My other question is related to the re-use of ua. In my Controller, I'd like to call an external subroutine, e.g.: MyApp::Network::Cool::getDetails($number).

• Should I pass $self to getDetails($self, $number) so I can re-use the $self->ua?
• Or should I simply do my $ua = Mojo::UserAgent->new; inside getDetails()?

[kraih]

I would probably consider that a model, and store an instance of the class in a helper during startup:

$self->helper(cool => sub { state $cool = MyApp::Network::Cool->new($app->ua) });

[kraih]

implicit return.

[hussam-qasem]

Thank you @kraih. And I'm sorry, I'm still struggling with syntax. In startup (decided to pass the whole $self so I can access $self->config too):

$self->helper(cool => sub { state $cool = MyApp::Network::Cool->new($self) });

In my Model:

package MyApp::Network::Cool;
use Mojo::Base -base, -signatures;

has 'app';
my $url = Mojo::URL->new('https://pie.dev/post');

sub get ($self, $number) {
  $url->query(number => $number);
  my $body = {'secret' => $self->config->{'secrets'};

  my $tx = $ua->post($url => json => $body);
  ...
}

However, $self has no access to config. Would you kindly guide me in the right direction?

Thanks again,

[flash548]

Probably should be something like:
$self->helper(cool => sub { state $cool = MyApp::Network::Cool->new(app => $self) });

then you can do

package MyApp::Network::Cool;
use Mojo::Base -base, -signatures;

has 'app';
has 'url' => sub { Mojo::URL->new('https://pie.dev/post') };

sub get ($self, $number) {
  $self->url->query(number => $number);
  my $body = {'secret' => $self->app->config->{'secrets'};

  my $tx = $self->app->ua->post($self->url => json => $body);
  ...
}

Disclaimer: I did not try the above, just thought would show syntax.

Regardless in your MyApp::Network::Cool->new constructor call, you need to assign $self object to something in your MyApp::Network::Cool class - as in my example I use the app property. Also I converted the url property to the has style so that it can be more of an instance variable type and thus can be accessed with $self->url style. Hope that helps some.

[flash548]

Thank you! And do I need to return $cool;? or is that useless?

To add little more context in case you're newer to perl. A perl sub's return (unless its explicitly returned by a return statement), is the last evaluated expression/statement result, so as @kraih stated, in the example case the last expression was the state variable assignment to $cool so therefore $cool is implicitly returned. But if you wanted to be more verbose - yes return $cool; would also work.

[hussam-qasem]

Thank you @kraih and @flash548. This is starting to make sense, and works as expected too. I wasn't aware of the implicit return.