Given that $thread is a blessed object your code

for ( $thread ) {
        my %data2;
        $data2{author}  = $thread->author;
        $data2{date}    = $thread->date;
        $data2{content} = $thread->content;
        push @d_body, \%data2;
    }
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is equivalent to

push @d_body, {};
$d_body[-1]->{$_} = $thread->$_ for ("author", "date", "content");
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Still I don't see why you need @d_body. I would simply use

my $d_body;
$d_body->{$_} = $thread->$_ for ("author", "date", "content");
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and later in the code

body=> [$d_body],
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