fix errors for api to be json

lib/App/Netdisco/Util/Web.pm

@@ -37,7 +37,7 @@ Whether the request should be interpreted as an API call.
 sub request_is_api {
   return (setting('api_token_lifetime')
     and request->accept =~ m/(?:json|javascript)/
-    and index(request->path, uri_for('/api')->path) == 0);
+    and index(var('orig_path'), uri_for('/api')->path) == 0);
 }
 
 =head2 sql_match( $value, $exact? )

lib/App/Netdisco/Web.pm

@@ -123,6 +123,11 @@ hook after_error_render => sub { setting('layout' => 'main') };
     for @port_columns;
 }
 
+# support for checking if this is an api request even after forward
+hook 'before' => sub {
+  vars->{'orig_path'} = request->path unless request->is_forward;
+};
+
 hook 'before' => sub {
   my $key = request->path;
   if (param('tab') and ($key !~ m/ajax/)) {

lib/App/Netdisco/Web/Plugin.pm

@@ -4,7 +4,6 @@ use Dancer ':syntax';
 use Dancer::Plugin;
 
 use App::Netdisco::Util::Web 'request_is_api';
-use Dancer::Plugin::REST 'status_bad_request';
 use Path::Class 'dir';
 
 set(
@@ -28,7 +27,9 @@ config->{engines}->{netdisco_template_toolkit}->{INCLUDE_PATH} ||= [ setting('vi
 register 'bang' => sub {
   if (request_is_api()) {
       content_type('application/json');
-      status_bad_request(@_);
+      set serializer => 'JSON';
+      status $_[1];
+      { error => $_[0] };
   }
   else { send_error(@_)  }
 };