From 4f4264f7ac384b02442bdf7c5cc6e838feb86c93 Mon Sep 17 00:00:00 2001
From: Eric Wong <e@80x24.org>
Date: Sat, 22 Aug 2015 11:41:19 +0000
Subject: search: split search indexing to a separate file

This makes organization easier and reduces the amount of code
loaded for a PSGI, mod_perl or CGI instance.
---
 lib/PublicInbox/SearchIdx.pm | 363 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 363 insertions(+)
 create mode 100644 lib/PublicInbox/SearchIdx.pm

(limited to 'lib/PublicInbox/SearchIdx.pm')

diff --git a/lib/PublicInbox/SearchIdx.pm b/lib/PublicInbox/SearchIdx.pm
new file mode 100644
index 00000000..408b21fd
--- /dev/null
+++ b/lib/PublicInbox/SearchIdx.pm
@@ -0,0 +1,363 @@
+# Copyright (C) 2015, all contributors <meta@public-inbox.org>
+# License: AGPLv3 or later (https://www.gnu.org/licenses/agpl-3.0.txt)
+# based on notmuch, but with no concept of folders, files or flags
+package PublicInbox::SearchIdx;
+use strict;
+use warnings;
+use base qw(PublicInbox::Search);
+use PublicInbox::MID qw/mid_clean mid_compressed/;
+*xpfx = *PublicInbox::Search::xpfx;
+
+sub new {
+	my ($class, $git_dir, $writable) = @_;
+	my $dir = $class->xdir($git_dir);
+	require Search::Xapian::WritableDatabase;
+	my $flag = Search::Xapian::DB_OPEN;
+	if ($writable == 1) {
+		require File::Path;
+		File::Path::mkpath($dir);
+		$flag = Search::Xapian::DB_CREATE_OR_OPEN;
+	}
+	my $db = Search::Xapian::WritableDatabase->new($dir, $flag);
+	bless { xdb => $db, git_dir => $git_dir }, $class;
+}
+
+sub add_message {
+	my ($self, $mime) = @_; # mime = Email::MIME object
+	my $db = $self->{xdb};
+
+	my $doc_id;
+	my $mid_orig = mid_clean($mime->header_obj->header('Message-ID'));
+	my $mid = mid_compressed($mid_orig);
+	my $was_ghost = 0;
+	my $ct_msg = $mime->header('Content-Type') || 'text/plain';
+
+	eval {
+		my $smsg = $self->lookup_message($mid);
+		my $doc;
+
+		if ($smsg) {
+			$smsg->ensure_metadata;
+			# convert a ghost to a regular message
+			# it will also clobber any existing regular message
+			$smsg->mime($mime);
+			$doc = $smsg->{doc};
+
+			my $type = xpfx('type');
+			eval {
+				$doc->remove_term($type . 'ghost');
+				$was_ghost = 1;
+			};
+
+			# probably does not exist:
+			eval { $doc->remove_term($type . 'mail') };
+			$doc->add_term($type . 'mail');
+		}  else {
+			$smsg = PublicInbox::SearchMsg->new($mime);
+			$doc = $smsg->{doc};
+			$doc->add_term(xpfx('mid') . $mid);
+		}
+
+		my $subj = $smsg->subject;
+
+		if (length $subj) {
+			$doc->add_term(xpfx('subject') . $subj);
+
+			my $path = $self->subject_path($subj);
+			$doc->add_term(xpfx('path') . mid_compressed($path));
+		}
+
+		my $from = $smsg->from_name;
+		my $date = $smsg->date;
+		my $ts = Search::Xapian::sortable_serialise($smsg->ts);
+		$doc->add_value(PublicInbox::Search::TS, $ts);
+
+		my $tg = $self->term_generator;
+
+		$tg->set_document($doc);
+		$tg->index_text($subj, 1, 'S') if $subj;
+		$tg->increase_termpos;
+		$tg->index_text($subj) if $subj;
+		$tg->increase_termpos;
+
+		$tg->index_text($smsg->from->format);
+		$tg->increase_termpos;
+
+		$mime->walk_parts(sub {
+			my ($part) = @_;
+			return if $part->subparts; # walk_parts already recurses
+			my $ct = $part->content_type || $ct_msg;
+
+			# account for filter bugs...
+			$ct =~ m!\btext/plain\b!i or return;
+
+			my (@orig, @quot);
+			my $body = $part->body;
+			$part->body_set('');
+			my @lines = split(/\n/, $body);
+			while (defined(my $l = shift @lines)) {
+				if ($l =~ /^\s*>/) {
+					push @quot, $l;
+				} else {
+					push @orig, $l;
+				}
+			}
+			if (@quot) {
+				$tg->index_text(join("\n", @quot), 0);
+				@quot = ();
+				$tg->increase_termpos;
+			}
+			if (@orig) {
+				$tg->index_text(join("\n", @orig));
+				@orig = ();
+				$tg->increase_termpos;
+			}
+		});
+
+		if ($was_ghost) {
+			$doc_id = $smsg->doc_id;
+			$self->link_message($smsg, 0);
+			$doc->set_data($smsg->to_doc_data);
+			$db->replace_document($doc_id, $doc);
+		} else {
+			$self->link_message($smsg, 0);
+			$doc->set_data($smsg->to_doc_data);
+			$doc_id = $db->add_document($doc);
+		}
+	};
+
+	if ($@) {
+		warn "failed to index message <$mid_orig>: $@\n";
+		return undef;
+	}
+	$doc_id;
+}
+
+# returns deleted doc_id on success, undef on missing
+sub remove_message {
+	my ($self, $mid_orig) = @_;
+	my $db = $self->{xdb};
+	my $doc_id;
+	$mid_orig = mid_clean($mid_orig);
+	my $mid = mid_compressed($mid_orig);
+
+	eval {
+		$doc_id = $self->find_unique_doc_id('mid', $mid);
+		$db->delete_document($doc_id) if defined $doc_id;
+	};
+
+	if ($@) {
+		warn "failed to remove message <$mid_orig>: $@\n";
+		return undef;
+	}
+	$doc_id;
+}
+
+sub term_generator { # write-only
+	my ($self) = @_;
+
+	my $tg = $self->{term_generator};
+	return $tg if $tg;
+
+	$tg = Search::Xapian::TermGenerator->new;
+	$tg->set_stemmer($self->stemmer);
+
+	$self->{term_generator} = $tg;
+}
+
+sub next_doc_id { $_[0]->{xdb}->get_lastdocid + 1 }
+
+# increments last_thread_id counter
+# returns a 64-bit integer represented as a hex string
+sub next_thread_id {
+	my ($self) = @_;
+	my $db = $self->{xdb};
+	my $last_thread_id = int($db->get_metadata('last_thread_id') || 0);
+
+	$db->set_metadata('last_thread_id', ++$last_thread_id);
+
+	$last_thread_id;
+}
+
+sub link_message {
+	my ($self, $smsg, $is_ghost) = @_;
+
+	if ($is_ghost) {
+		$smsg->ensure_metadata;
+	} else {
+		$self->link_message_to_parents($smsg);
+	}
+}
+
+sub link_message_to_parents {
+	my ($self, $smsg) = @_;
+	my $doc = $smsg->{doc};
+	my $mid = mid_compressed($smsg->mid);
+	my $mime = $smsg->mime;
+	my $refs = $mime->header_obj->header('References');
+	my @refs = $refs ? ($refs =~ /<([^>]+)>/g) : ();
+	my $irt = $mime->header_obj->header('In-Reply-To');
+	if ($irt) {
+		$irt = mid_compressed(mid_clean($irt));
+
+		# maybe some crazies will try to make a circular reference:
+		if ($irt eq $mid) {
+			$irt = undef;
+		} else {
+			# last References should be $irt
+			# we will de-dupe later
+			push @refs, $irt;
+		}
+	}
+
+	my $tid;
+	if (@refs) {
+		my @crefs = map { mid_compressed($_) } @refs;
+		my %uniq = ($mid => 1);
+
+		# prevent circular references via References: here:
+		@refs = ();
+		foreach my $ref (@crefs) {
+			next if $uniq{$ref};
+			$uniq{$ref} = 1;
+			push @refs, $ref;
+		}
+	}
+	if (@refs) {
+		$doc->add_term(xpfx('inreplyto') . $irt) if defined $irt;
+		$smsg->{references_sorted} = '<'.join('><', @refs).'>';
+
+		my $ref_pfx = xpfx('references');
+
+		# first ref *should* be the thread root,
+		# but we can never trust clients to do the right thing
+		my $ref = shift @refs;
+		$doc->add_term($ref_pfx . $ref);
+		$tid = $self->_resolve_mid_to_tid($ref);
+
+		# the rest of the refs should point to this tid:
+		foreach $ref (@refs) {
+			$doc->add_term($ref_pfx . $ref);
+			my $ptid = $self->_resolve_mid_to_tid($ref);
+			if ($tid ne $ptid) {
+				$self->merge_threads($tid, $ptid);
+			}
+		}
+	} else {
+		$tid = $self->next_thread_id;
+	}
+	$doc->add_term(xpfx('thread') . $tid);
+}
+
+sub index_blob {
+	my ($self, $git, $blob) = @_;
+	my $mime = do_cat_mail($git, $blob) or return;
+	eval { $self->add_message($mime) };
+	warn "W: index_blob $blob: $@\n" if $@;
+}
+
+sub unindex_blob {
+	my ($self, $git, $blob) = @_;
+	my $mime = do_cat_mail($git, $blob) or return;
+	my $mid = $mime->header_obj->header('Message-ID');
+	eval { $self->remove_message($mid) } if defined $mid;
+	warn "W: unindex_blob $blob: $@\n" if $@;
+}
+
+sub do_cat_mail {
+	my ($git, $blob) = @_;
+	my $mime = eval {
+		my $str = $git->cat_file($blob);
+		Email::MIME->new($str);
+	};
+	$@ ? undef : $mime;
+}
+
+# indexes all unindexed messages
+sub index_sync {
+	my ($self, $head) = @_;
+	require PublicInbox::GitCatFile;
+	my $db = $self->{xdb};
+	my $hex = '[a-f0-9]';
+	my $h40 = $hex .'{40}';
+	my $addmsg = qr!^:000000 100644 \S+ ($h40) A\t${hex}{2}/${hex}{38}$!;
+	my $delmsg = qr!^:100644 000000 ($h40) \S+ D\t${hex}{2}/${hex}{38}$!;
+	$head ||= 'HEAD';
+
+	$db->begin_transaction;
+	eval {
+		my $git = PublicInbox::GitCatFile->new($self->{git_dir});
+
+		my $latest = $db->get_metadata('last_commit');
+		my $range = length $latest ? "$latest..$head" : $head;
+		$latest = undef;
+
+		# get indexed messages
+		my @cmd = ('git', "--git-dir=$self->{git_dir}", "log",
+			    qw/--reverse --no-notes --no-color --raw -r
+			       --no-abbrev/, $range);
+		my $pid = open(my $log, '-|', @cmd) or
+			die('open` '.join(' ', @cmd) . " pipe failed: $!\n");
+
+		while (my $line = <$log>) {
+			if ($line =~ /$addmsg/o) {
+				$self->index_blob($git, $1);
+			} elsif ($line =~ /$delmsg/o) {
+				$self->unindex_blob($git, $1);
+			} elsif ($line =~ /^commit ($h40)/o) {
+				$latest = $1;
+			}
+		}
+		close $log;
+		$db->set_metadata('last_commit', $latest) if defined $latest;
+	};
+	if ($@) {
+		warn "indexing failed: $@\n";
+		$db->cancel_transaction;
+	} else {
+		$db->commit_transaction;
+	}
+}
+
+# this will create a ghost as necessary
+sub _resolve_mid_to_tid {
+	my ($self, $mid) = @_;
+
+	my $smsg = $self->lookup_message($mid) || $self->create_ghost($mid);
+	$smsg->thread_id;
+}
+
+sub create_ghost {
+	my ($self, $mid, $tid) = @_;
+
+	$mid = mid_compressed($mid);
+	$tid = $self->next_thread_id unless defined $tid;
+
+	my $doc = Search::Xapian::Document->new;
+	$doc->add_term(xpfx('mid') . $mid);
+	$doc->add_term(xpfx('thread') . $tid);
+	$doc->add_term(xpfx('type') . 'ghost');
+
+	my $smsg = PublicInbox::SearchMsg->wrap($doc, $mid);
+	$self->link_message($smsg, 1);
+	$self->{xdb}->add_document($doc);
+
+	$smsg;
+}
+
+sub merge_threads {
+	my ($self, $winner_tid, $loser_tid) = @_;
+	my ($head, $tail) = $self->find_doc_ids('thread', $loser_tid);
+	my $thread_pfx = xpfx('thread');
+	my $db = $self->{xdb};
+
+	for (; $head != $tail; $head->inc) {
+		my $docid = $head->get_docid;
+		my $doc = $db->get_document($docid);
+		$doc->remove_term($thread_pfx . $loser_tid);
+		$doc->add_term($thread_pfx . $winner_tid);
+		$db->replace_document($docid, $doc);
+	}
+}
+
+1;
-- 
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