[PATCH 3/4] watch: switch IMAP and NNTP fetch loops to NetReader

[Eric Wong <e@80x24.org>]

NetReader::<imap|nntp>_each were based on the -watch
code they now replace.
---
 lib/PublicInbox/NetReader.pm |  15 ++-
 lib/PublicInbox/Watch.pm     | 249 +++++++----------------------------
 t/imapd.t                    |   2 +-
 t/nntpd.t                    |   2 +-
 4 files changed, 63 insertions(+), 205 deletions(-)

diff --git a/lib/PublicInbox/NetReader.pm b/lib/PublicInbox/NetReader.pm
index 2a453217..f3988f15 100644
--- a/lib/PublicInbox/NetReader.pm
+++ b/lib/PublicInbox/NetReader.pm
@@ -366,6 +366,13 @@ sub _imap_do_msg ($$$$$) {
 	$eml_cb->($uri, $uid, $kw, PublicInbox::Eml->new($raw), @args);
 }
 
+sub run_commit_cb ($) {
+	my ($self) = @_;
+	my $cmt_cb_args = $self->{on_commit} or return;
+	my ($cb, @args) = @$cmt_cb_args;
+	$cb->(@args);
+}
+
 sub _imap_fetch_all ($$$) {
 	my ($self, $mic, $uri) = @_;
 	my $sec = uri_section($uri);
@@ -451,6 +458,7 @@ sub _imap_fetch_all ($$$) {
 			}
 			last if $self->{quit};
 		}
+		run_commit_cb($self);
 		$itrk->update_last($r_uidval, $last_uid) if $itrk;
 	} until ($err || $self->{quit});
 	$err;
@@ -490,7 +498,7 @@ sub imap_each {
 		local $self->{eml_each} = [ $eml_cb, @args ];
 		$err = _imap_fetch_all($self, $mic, $uri);
 	} else {
-		$err = "E: not connected: $!";
+		$err = "E: <$uri> not connected: $!";
 	}
 	warn $err if $err;
 	$mic;
@@ -555,6 +563,7 @@ sub _nntp_fetch_all ($$$) {
 		last if $self->{quit};
 		$art = $_;
 		if (--$n < 0) {
+			run_commit_cb($self);
 			$itrk->update_last(0, $last_art) if $itrk;
 			$n = $self->{max_batch};
 		}
@@ -575,6 +584,7 @@ sub _nntp_fetch_all ($$$) {
 		$eml_cb->($uri, $art, [], PublicInbox::Eml->new(\$raw), @args);
 		$last_art = $art;
 	}
+	run_commit_cb($self);
 	$itrk->update_last(0, $last_art) if $itrk;
 	$err;
 }
@@ -585,12 +595,13 @@ sub nntp_each {
 	my $sec = uri_section($uri);
 	local $0 = $uri->group ." $sec";
 	my $nn = nn_get($self, $uri);
+	return if $self->{quit};
 	my $err;
 	if ($nn) {
 		local $self->{eml_each} = [ $eml_cb, @args ];
 		$err = _nntp_fetch_all($self, $nn, $uri);
 	} else {
-		$err = "E: not connected: $!";
+		$err = "E: <$uri> not connected: $!";
 	}
 	warn $err if $err;
 	$nn;
diff --git a/lib/PublicInbox/Watch.pm b/lib/PublicInbox/Watch.pm
index 4b009a28..0b72bd16 100644
--- a/lib/PublicInbox/Watch.pm
+++ b/lib/PublicInbox/Watch.pm
@@ -309,102 +309,38 @@ sub imap_import_msg ($$$$$) {
 	}
 }
 
-sub imap_fetch_all ($$$) {
-	my ($self, $mic, $uri) = @_;
-	my $sec = uri_section($uri);
-	my $mbx = $uri->mailbox;
-	$mic->Clear(1); # trim results history
-	$mic->examine($mbx) or return "E: EXAMINE $mbx ($sec) failed: $!";
-	my ($r_uidval, $r_uidnext);
-	for ($mic->Results) {
-		/^\* OK \[UIDVALIDITY ([0-9]+)\].*/ and $r_uidval = $1;
-		/^\* OK \[UIDNEXT ([0-9]+)\].*/ and $r_uidnext = $1;
-		last if $r_uidval && $r_uidnext;
-	}
-	$r_uidval //= $mic->uidvalidity($mbx) //
-		return "E: $uri cannot get UIDVALIDITY";
-	$r_uidnext //= $mic->uidnext($mbx) //
-		return "E: $uri cannot get UIDNEXT";
-	my $itrk = PublicInbox::IMAPTracker->new($$uri);
-	my ($l_uidval, $l_uid) = $itrk->get_last;
-	$l_uidval //= $r_uidval; # first time
-	$l_uid //= 1;
-	if ($l_uidval != $r_uidval) {
-		return "E: $uri UIDVALIDITY mismatch\n".
-			"E: local=$l_uidval != remote=$r_uidval";
-	}
-	my $r_uid = $r_uidnext - 1;
-	if ($l_uid != 1 && $l_uid > $r_uid) {
-		return "E: $uri local UID exceeds remote ($l_uid > $r_uid)\n".
-			"E: $uri strangely, UIDVALIDLITY matches ($l_uidval)\n";
-	}
-	return if $l_uid >= $r_uid; # nothing to do
-
-	warn "I: $uri fetching UID $l_uid:$r_uid\n";
-	$mic->Uid(1); # the default, we hope
-	my $bs = $self->{imap_opt}->{$sec}->{batch_size} // 1;
-	my $req = $mic->imap4rev1 ? 'BODY.PEEK[]' : 'RFC822.PEEK';
-
-	# TODO: FLAGS may be useful for personal use
-	my $key = $req;
-	$key =~ s/\.PEEK//;
-	my ($uids, $batch);
+sub net_cb { # NetReader::(nntp|imap)_each callback
+	my ($uri, $art, $kw, $eml, $self, $inboxes) = @_;
+	local $self->{cur_uid} = $art; # IMAP UID or NNTP article
+	if (ref($inboxes)) {
+		my @ibx = @$inboxes;
+		my $last = pop @ibx;
+		for my $ibx (@ibx) {
+			my $tmp = PublicInbox::Eml->new(\($eml->as_string));
+			import_eml($self, $ibx, $tmp);
+		}
+		import_eml($self, $last, $eml);
+	} elsif ($inboxes eq 'watchspam') {
+		$self->{pi_cfg}->each_inbox(\&remove_eml_i,
+				$self, $eml, "$uri #$art");
+	} else {
+		die "BUG: destination unknown $inboxes";
+	}
+}
+
+sub imap_fetch_all ($$) {
+	my ($self, $uri) = @_;
 	my $warn_cb = $SIG{__WARN__} || \&CORE::warn;
+	$self->{incremental} = 1;
+	$self->{on_commit} = [ \&_done_for_now, $self ];
+	local $self->{cur_uid};
 	local $SIG{__WARN__} = sub {
-		my $pfx = ($_[0] // '') =~ /^([A-Z]: )/g ? $1 : '';
-		$batch //= '?';
-		$warn_cb->("$pfx$uri UID:$batch\n", @_);
+		my $pfx = ($_[0] // '') =~ /^([A-Z]: |# )/g ? $1 : '';
+		my $uid = $self->{cur_uid};
+		$warn_cb->("$pfx$uri", $uid ? ("UID:$uid") : (), "\n", @_);
 	};
-	my $err;
-	do {
-		# I wish "UID FETCH $START:*" could work, but:
-		# 1) servers do not need to return results in any order
-		# 2) Mail::IMAPClient doesn't offer a streaming API
-		$uids = $mic->search("UID $l_uid:*") or
-			return "E: $uri UID SEARCH $l_uid:* error: $!";
-		return if scalar(@$uids) == 0;
-
-		# RFC 3501 doesn't seem to indicate order of UID SEARCH
-		# responses, so sort it ourselves.  Order matters so
-		# IMAPTracker can store the newest UID.
-		@$uids = sort { $a <=> $b } @$uids;
-
-		# Did we actually get new messages?
-		return if $uids->[0] < $l_uid;
-
-		$l_uid = $uids->[-1] + 1; # for next search
-		my $last_uid;
-		my $n = $self->{max_batch};
-
-		while (scalar @$uids) {
-			if (--$n < 0) {
-				_done_for_now($self);
-				$itrk->update_last($r_uidval, $last_uid);
-				$n = $self->{max_batch};
-			}
-			my @batch = splice(@$uids, 0, $bs);
-			$batch = join(',', @batch);
-			local $0 = "UID:$batch $mbx $sec";
-			my $r = $mic->fetch_hash($batch, $req, 'FLAGS');
-			unless ($r) { # network error?
-				$err = "E: $uri UID FETCH $batch error: $!";
-				last;
-			}
-			for my $uid (@batch) {
-				# messages get deleted, so holes appear
-				my $per_uid = delete $r->{$uid} // next;
-				my $raw = delete($per_uid->{$key}) // next;
-				my $fl = $per_uid->{FLAGS} // '';
-				imap_import_msg($self, $uri, $uid, \$raw, $fl);
-				$last_uid = $uid;
-				last if $self->{quit};
-			}
-			last if $self->{quit};
-		}
-		_done_for_now($self);
-		$itrk->update_last($r_uidval, $last_uid);
-	} until ($err || $self->{quit});
-	$err;
+	PublicInbox::NetReader::imap_each($self, $uri, \&net_cb, $self,
+					$self->{imap}->{$$uri});
 }
 
 sub imap_idle_once ($$$$) {
@@ -444,8 +380,11 @@ sub watch_imap_idle_1 ($$$) {
 		$mic //= PublicInbox::IMAPClient->new(%$mic_arg);
 		my $err;
 		if ($mic && $mic->IsConnected) {
-			$err = imap_fetch_all($self, $mic, $uri);
-			$err //= imap_idle_once($self, $mic, $intvl, $uri);
+			local $self->{mics_cached}->{$sec} = $mic;
+			my $m = imap_fetch_all($self, $uri);
+			$m == $mic or die "BUG: wrong mic";
+			$mic->IsConnected and
+				$err = imap_idle_once($self, $mic, $intvl, $uri)
 		} else {
 			$err = "E: not connected: $!";
 		}
@@ -540,43 +479,27 @@ sub event_step {
 sub watch_imap_fetch_all ($$) {
 	my ($self, $uris) = @_;
 	for my $uri (@$uris) {
-		my $sec = uri_section($uri);
-		my $mic_arg = $self->{mic_arg}->{$sec} or
-			die "BUG: no Mail::IMAPClient->new arg for $sec";
-		my $mic = PublicInbox::IMAPClient->new(%$mic_arg) or next;
-		my $err = imap_fetch_all($self, $mic, $uri);
+		imap_fetch_all($self, $uri);
 		last if $self->{quit};
-		warn $err, "\n" if $err;
 	}
 }
 
 sub watch_nntp_fetch_all ($$) {
 	my ($self, $uris) = @_;
-	for my $uri (@$uris) {
-		my $sec = uri_section($uri);
-		my $nn_arg = $self->{nn_arg}->{$sec} or
-			die "BUG: no Net::NNTP->new arg for $sec";
-		my $nntp_opt = $self->{nntp_opt}->{$sec};
-		my $nn = nn_new($nn_arg, $nntp_opt, $uri);
-		unless ($nn) {
-			warn "E: $uri: \$!=$!\n";
-			next;
-		}
-		last if $self->{quit};
-		if (my $postconn = $nntp_opt->{-postconn}) {
-			for my $m_arg (@$postconn) {
-				my ($method, @args) = @$m_arg;
-				$nn->$method(@args) and next;
-				warn "E: <$uri> $method failed\n";
-				$nn = undef;
-				last;
-			}
-		}
+	$self->{incremental} = 1;
+	$self->{on_commit} = [ \&_done_for_now, $self ];
+	my $warn_cb = $SIG{__WARN__} || \&CORE::warn;
+	local $self->{cur_uid};
+	my $uri = '';
+	local $SIG{__WARN__} = sub {
+		my $pfx = ($_[0] // '') =~ /^([A-Z]: |# )/g ? $1 : '';
+		my $art = $self->{cur_uid};
+		$warn_cb->("$pfx$uri", $art ? ("ARTICLE $art") : (), "\n", @_);
+	};
+	for $uri (@$uris) {
+		PublicInbox::NetReader::nntp_each($self, $uri, \&net_cb, $self,
+					$self->{nntp}->{$$uri});
 		last if $self->{quit};
-		if ($nn) {
-			my $err = nntp_fetch_all($self, $nn, $uri);
-			warn $err, "\n" if $err;
-		}
 	}
 }
 
@@ -640,82 +563,6 @@ sub watch_imap_init ($$) {
 	}
 }
 
-sub nntp_fetch_all ($$$) {
-	my ($self, $nn, $uri) = @_;
-	my ($group, $num_a, $num_b) = $uri->group;
-	my $sec = uri_section($uri);
-	my ($nr, $beg, $end) = $nn->group($group);
-	unless (defined($nr)) {
-		chomp(my $msg = $nn->message);
-		return "E: GROUP $group <$sec> $msg";
-	}
-
-	# IMAPTracker is also used for tracking NNTP, UID == article number
-	# LIST.ACTIVE can get the equivalent of UIDVALIDITY, but that's
-	# expensive.  So we assume newsgroups don't change:
-	my $itrk = PublicInbox::IMAPTracker->new($$uri);
-	my (undef, $l_art) = $itrk->get_last;
-	$l_art //= $beg; # initial import
-
-	# allow users to specify articles to refetch
-	# cf. https://tools.ietf.org/id/draft-gilman-news-url-01.txt
-	# nntp://example.com/inbox.foo/$num_a-$num_b
-	$l_art = $num_a if defined($num_a) && $num_a < $l_art;
-	$end = $num_b if defined($num_b) && $num_b < $end;
-
-	return if $l_art >= $end; # nothing to do
-	$beg = $l_art + 1;
-
-	warn "I: $uri fetching ARTICLE $beg..$end\n";
-	my $warn_cb = $SIG{__WARN__} || \&CORE::warn;
-	my ($err, $art);
-	local $SIG{__WARN__} = sub {
-		my $pfx = ($_[0] // '') =~ /^([A-Z]: )/g ? $1 : '';
-		$warn_cb->("$pfx$uri ", $art ? ("ARTICLE $art") : (), "\n", @_);
-	};
-	my $inboxes = $self->{nntp}->{$$uri};
-	my $last_art;
-	my $n = $self->{max_batch};
-	for ($beg..$end) {
-		last if $self->{quit};
-		$art = $_;
-		if (--$n < 0) {
-			_done_for_now($self);
-			$itrk->update_last(0, $last_art);
-			$n = $self->{max_batch};
-		}
-		my $raw = $nn->article($art);
-		unless (defined($raw)) {
-			my $msg = $nn->message;
-			if ($nn->code == 421) { # pseudo response from Net::Cmd
-				$err = "E: $msg";
-				last;
-			} else { # probably just a deleted message (spam)
-				warn "W: $msg";
-				next;
-			}
-		}
-		s/\r\n/\n/ for @$raw;
-		$raw = join('', @$raw);
-		if (ref($inboxes)) {
-			for my $ibx (@$inboxes) {
-				my $eml = PublicInbox::Eml->new($raw);
-				import_eml($self, $ibx, $eml);
-			}
-		} elsif ($inboxes eq 'watchspam') {
-			my $eml = PublicInbox::Eml->new(\$raw);
-			$self->{pi_cfg}->each_inbox(\&remove_eml_i,
-					$self, $eml, "$uri ARTICLE $art");
-		} else {
-			die "BUG: destination unknown $inboxes";
-		}
-		$last_art = $art;
-	}
-	_done_for_now($self);
-	$itrk->update_last(0, $last_art);
-	$err;
-}
-
 sub watch_nntp_init ($$) {
 	my ($self, $poll) = @_;
 	nntp_common_init($self); # read args from config
diff --git a/t/imapd.t b/t/imapd.t
index 0583dfdd..f1b498a7 100644
--- a/t/imapd.t
+++ b/t/imapd.t
@@ -507,7 +507,7 @@ SKIP: {
 	$ii->close;
 	PublicInbox::DS->Reset;
 	seek($err, 0, 0);
-	my @err = grep(!/^I:/, <$err>);
+	my @err = grep(!/^(?:I:|#)/, <$err>);
 	is(@err, 0, 'no warnings/errors from -watch'.join(' ', @err));
 
 	if ($ENV{TEST_KILL_IMAPD}) { # not sure how reliable this test can be
diff --git a/t/nntpd.t b/t/nntpd.t
index 18aaccbe..16a2ab76 100644
--- a/t/nntpd.t
+++ b/t/nntpd.t
@@ -459,7 +459,7 @@ sub test_watch {
 	$cfg->each_inbox(sub { shift->unsubscribe_unlock('ident') });
 	$ii->close;
 	PublicInbox::DS->Reset;
-	my @err = grep(!/^I:/, <$err>);
+	my @err = grep(!/^(?:I:|#)/, <$err>);
 	is(@err, 0, 'no warnings/errors from -watch'.join(' ', @err));
 	my @ls = xqx(['git', "--git-dir=$inboxdir", qw(ls-tree -r HEAD)]);
 	isnt(scalar(@ls), 0, 'imported something');