ありがちな処理を Exception::Tiny と Try::Lite で

arigachi.pl

#!/usr/bin/env perl
use strict;
use warnings;
use feature qw/say/;
use utf8;
use Exception::Tiny;

package MyException;
use parent 'Exception::Tiny';
use Class::Accessor::Lite (
    ro => [qw/ error_code /],
);

package Controller;
use Try::Lite;
use Log::Minimal;
use Data::Dumper;

sub index {
    my $params = shift;

    my $result = try {
        Validator->validate($params);
        Model->create_foo($params);
    }
        'MyException' => sub { $@ },
        '*' => sub {
            critf('unknown error:%s', $@);
            render('500.tt');
        };

    if ( MyException->caught($result) ) {
        warnf('error_code:%s', $result->error_code);
        return render('error.tt', +{
            error_code => $result->error_code,
        });
    }
}

sub render {
    say 'tmpl:', shift;
    say Dumper shift;
}

package Validator;
sub validate {
    MyException->throw(
        message    => 'Error occured: validate params',
        error_code => 'validate_error',
    );
}

package Model;
sub prepare {
    MyException->throw(
        message    => 'Error occured: prepare to create',
        error_code => 'prepare_error',
    );
}
sub create_foo {
    prepare();
    DataSource->create;
}

package DataSource;
use Try::Lite;
use Log::Minimal;

sub create {
    dbi_do();
}
sub dbi_do { die 'DB error' }


package main;
use Test::Mock::Guard qw/mock_guard/;

my $g1 = mock_guard(Validator => +{
    validate => +{},
});
my $g2 = mock_guard(Model => +{
    prepare => +{},
});
# my $g3 = mock_guard(Model => +{
#     create => sub {
#         MyException->throw(
#             message    => 'Error occured: create',
#             error_code => 'create_error',
#         );
#     },
# });

Controller->index;