extindex: various --watch signal handling fixes

We need to clobber the SIGUSR1 resync queue on SIGHUP to
invalidate old inbox objects.  Furthermore, the lengthy
initial scan needs to ignore signals intended for the
event loop to avoid unexpected behavior.  Finally, add
some progress output to inform users on the terminal
to inform users' of progress.

diff --git a/lib/PublicInbox/ExtSearchIdx.pm b/lib/PublicInbox/ExtSearchIdx.pm
index 53ff2ca183656e5fd1a6dd72b58db9e46096691d..778154a564b20433cf841adcd596ae121bb63ac7 100644 (file)
--- a/lib/PublicInbox/ExtSearchIdx.pm
+++ b/lib/PublicInbox/ExtSearchIdx.pm
@@ -1008,6 +1008,7 @@ sub eidx_reload { # -extindex --watch SIGHUP handler
        if ($self->{cfg}) {
                my $pr = $self->{-watch_sync}->{-opt}->{-progress};
                $pr->('reloading ...') if $pr;
+               delete $self->{-resync_queue};
                @{$self->{ibx_list}} = ();
                %{$self->{ibx_map}} = ();
                delete $self->{-watch_sync}->{id2pos};
@@ -1043,6 +1044,10 @@ sub event_step { # PublicInbox::DS::requeue callback
 
 sub eidx_watch { # public-inbox-extindex --watch main loop
        my ($self, $opt) = @_;
+       local %SIG = %SIG;
+       for my $sig (qw(HUP USR1 TSTP QUIT INT TERM)) {
+               $SIG{$sig} = sub { warn "SIG$sig ignored while scanning\n" };
+       }
        require PublicInbox::InboxIdle;
        require PublicInbox::DS;
        require PublicInbox::Syscall;
@@ -1052,6 +1057,8 @@ sub eidx_watch { # public-inbox-extindex --watch main loop
                $idler->watch_inbox($_) for @{$self->{ibx_list}};
        }
        $_->subscribe_unlock(__PACKAGE__, $self) for @{$self->{ibx_list}};
+       my $pr = $opt->{-progress};
+       $pr->("performing initial scan ...\n") if $pr;
        my $sync = eidx_sync($self, $opt); # initial sync
        return if $sync->{quit};
        my $oldset = PublicInbox::Sigfd::block_signals();
@@ -1067,7 +1074,7 @@ sub eidx_watch { # public-inbox-extindex --watch main loop
        $sig->{QUIT} = $sig->{INT} = $sig->{TERM} = $quit;
        my $sigfd = PublicInbox::Sigfd->new($sig,
                                        $PublicInbox::Syscall::SFD_NONBLOCK);
-       local %SIG = (%SIG, %$sig) if !$sigfd;
+       %SIG = (%SIG, %$sig) if !$sigfd;
        local $self->{-watch_sync} = $sync; # for ->on_inbox_unlock
        if (!$sigfd) {
                # wake up every second to accept signals if we don't
@@ -1076,6 +1083,7 @@ sub eidx_watch { # public-inbox-extindex --watch main loop
                PublicInbox::DS->SetLoopTimeout(1000);
        }
        PublicInbox::DS->SetPostLoopCallback(sub { !$sync->{quit} });
+       $pr->("initial scan complete, entering event loop\n") if $pr;
        PublicInbox::DS->EventLoop; # calls InboxIdle->event_step
        done($self);
 }