use Data::Dumper;
use Storable qw(nfreeze thaw);

my $request = { TYPE => 'UPLOAD', DATA => { file1 => 'content1', file2 => 'content2' } };
my $serialized = nfreeze $request;  # send this binary string

my $deserialized = thaw $serialized;  # round trip!
print Dumper $deserialized;