my %URLS = (
    upload   => 'https://somewhere.com/api1',
    process  => 'https://somewhere.com/=GUID=/api2',
    );

my $guid = upload_file( $ARGV[0] );
my $rtn  = process_file( $guid );

sub upload_file {
    my $fn = shift;
    # LWP::UserAgent stuff
    my $g = $ua->post( $URLS{ upload } . '?' . $fn );
    return $g;
}

sub process_file {
    my $guid = shift;
    # LWP::UserAgent stuff
    ( my $this_url = $URLS{ process } ) =~ s/=GUID=/$guid/;
    my $result = $ua->post( $this_url );
    return $result || 0;
}