fix poller count and refactor for clarity

Netdisco/bin/netdisco-daemon

@@ -9,19 +9,10 @@ use Net::Domain 'hostfqdn';
 use Role::Tiny;
 use Try::Tiny;
 
-my $pp = Parallel::Prefork->new(
-  max_workers => (setting('daemon_workers') || 5),
-  spawn_interval => 1,
-  before_fork => \&set_next_worker_role,
-  after_fork  => \&register_worker,
-  on_child_reap => \&unregister_worker,
-  trap_signals => {
-    TERM => 'TERM',
-    INT  => 'TERM',
-  },
-);
+# Parallel::Prefork instance
+my $pp = undef;
 
-# tracks worker pids and their roles
+# track worker pids and their roles
 my %workers = ();
 my $next_role = undef;
 
@@ -34,25 +25,15 @@ newdaemon(
 
 sub gd_preconfig {
   my $gd = shift;
-  my $daemon = schema('daemon');
 
   # deploy the daemon's local DB schema
-  try {
-      $daemon->storage->dbh_do(sub {
-        my ($storage, $dbh) = @_;
-        $dbh->selectrow_arrayref("SELECT * FROM admin WHERE 0 = 1");
-      });
-  }
-  catch { $daemon->deploy };
-
-  $daemon->storage->disconnect;
-  if ($daemon->get_db_version < $daemon->schema_version) {
-      $daemon->upgrade;
-  }
+  _deploy_daemon_db();
 
   # used for locking jobs in central Pg queue
   $gd->{nd_host} = hostfqdn;
 
+  _bootstrap_prefork();
+
   # do not remove this line - required by Daemon::Generic
   return ();
 }
@@ -64,20 +45,16 @@ sub gd_run_body {
   $gd->handle_term
     if $pp->signal_received =~ m/^(?:TERM|INT)$/;
 
-  $gd->handle_hup
-    if $pp->signal_received eq 'HUP';
-
-  if ($pp->num_workers < $pp->max_workers) {
-      $pp->start and return;
-      with "Netdisco::Daemon::Worker::$next_role";
-      print STDERR ">>> new $next_role worker started.\n";
-      $gd->worker_body;
-      $pp->finish;
-  }
+  $pp->start(sub {
+    with "Netdisco::Daemon::Worker::$next_role";
+    print STDERR ">>> new $next_role worker started.\n";
+    $gd->worker_body;
+  });
 
   # I don't think Parallel::Prefork ever returns from start()
   # until a child exits. Not sure this is ever reached.
-  $gd->gd_sleep( setting('daemon_sleep_time') || 5 );
+  $gd->gd_sleep( setting('daemon_sleep_time') || 5 )
+    if not $pp->signal_received;
 }
 
 sub register_worker {
@@ -112,8 +89,8 @@ sub _find_next_worker_role {
 
   return 'Manager' if $manager < 1;
 
-  my $need_poller  = $poller < (setting('daemon_pollers') || 2);
-  my $need_inter   = $inter < (setting('daemon_interactives') || 2);
+  my $need_poller = $poller < setting('daemon_pollers');
+  my $need_inter  = $inter < setting('daemon_interactives');
 
   if ($need_poller and $need_inter) {
       return (int(rand(2)) ? 'Interactive' : 'Poller');
@@ -135,6 +112,42 @@ END {
   $pp->wait_all_children;
 }
 
+sub _deploy_daemon_db {
+  my $daemon = schema('daemon');
+
+  try {
+      $daemon->storage->dbh_do(sub {
+        my ($storage, $dbh) = @_;
+        $dbh->selectrow_arrayref("SELECT * FROM admin WHERE 0 = 1");
+      });
+  }
+  catch { $daemon->deploy };
+
+  $daemon->storage->disconnect;
+  if ($daemon->get_db_version < $daemon->schema_version) {
+      $daemon->upgrade;
+  }
+}
+
+sub _bootstrap_prefork {
+  # set defaults
+  set(daemon_pollers => 2) if !defined setting('daemon_pollers');
+  set(daemon_interactives => 2) if !defined setting('daemon_interactives');
+
+  # need to do this after setting defaults
+  $pp = Parallel::Prefork->new(
+    max_workers => (1 + setting('daemon_pollers') + setting('daemon_interactives')),
+    spawn_interval => 2,
+    before_fork => \&set_next_worker_role,
+    after_fork  => \&register_worker,
+    on_child_reap => \&unregister_worker,
+    trap_signals => {
+      TERM => 'TERM',
+      INT  => 'TERM',
+    },
+  );
+}
+
 # nullify this to permit Parallel::Prefork to register handlers instead
 sub gd_setup_signals {}
 

Netdisco/config.yml

@@ -27,8 +27,3 @@ engines:
     end_tag:   '%]'
     PRE_CHOMP: 1
 
-# how many daemon processes
-# NB one worker will always be a Queue Manager
-daemon_workers: 2
-daemon_pollers: 0
-daemon_interactives: 2