implement port properties table and error disable gathering to it

lib/App/Netdisco/Worker/Plugin/Discover/PortProperties.pm

@@ -0,0 +1,48 @@
+package App::Netdisco::Worker::Plugin::Discover::PortProperties;
+
+use Dancer ':syntax';
+use App::Netdisco::Worker::Plugin;
+use aliased 'App::Netdisco::Worker::Status';
+
+use App::Netdisco::Transport::SNMP ();
+use Dancer::Plugin::DBIC 'schema';
+
+register_worker({ phase => 'main', driver => 'snmp' }, sub {
+  my ($job, $workerconf) = @_;
+
+  my $device = $job->device;
+  return unless $device->in_storage;
+  my $snmp = App::Netdisco::Transport::SNMP->reader_for($device)
+    or return Status->defer("discover failed: could not SNMP connect to $device");
+
+  my $interfaces = $snmp->interfaces;
+  my $err_cause = $snmp->i_err_disable_cause;
+
+  if (!defined $err_cause or !defined $interfaces) {
+      return Status->info(sprintf ' [%s] props - 0 errored ports', $device->ip);
+  }
+
+  # build device port properties info suitable for DBIC
+  my @portproperties;
+  foreach my $entry (keys %$err_cause) {
+      my $port = $interfaces->{$entry};
+      next unless $port;
+
+      push @portproperties, {
+          port => $port,
+          error_disable_cause => $err_cause->{$entry},
+      };
+  }
+
+  schema('netdisco')->txn_do(sub {
+    my $gone = $device->properties_ports->delete;
+    debug sprintf ' [%s] props - removed %d ports with properties',
+      $device->ip, $gone;
+    $device->properties_ports->populate(\@portproperties);
+
+    return Status->info(sprintf ' [%s] props - added %d new port properties',
+      $device->ip, scalar @portproperties);
+  });
+});
+
+true;