my $json = { 'username' => 'foo',
             'password' => 'bar',
};
my $encoded = to_json($json);
my $escaped = uri_escape($encoded);  #string.
my $query = '&inputparms='.$escaped;
my $url = $rest_url.$query;
print "$url\n";
my $response = $ua->post($rest_url);
my $content = undef;
if ($response->is_success) {
    $content = $response->content;
}