X-Git-Url: http://git.vanrenterghem.biz/git.ikiwiki.info.git/blobdiff_plain/38affb0c1c4e2b89beb63d6f8dc3f172eee7bd02..34115a34e0593e999b7a279e07293b090012082a:/IkiWiki/Plugin/aggregate.pm

diff --git a/IkiWiki/Plugin/aggregate.pm b/IkiWiki/Plugin/aggregate.pm
index cfc4ec955..ba40ee6bc 100644
--- a/IkiWiki/Plugin/aggregate.pm
+++ b/IkiWiki/Plugin/aggregate.pm
@@ -33,33 +33,62 @@ sub getopt () { #{{{
 sub checkconfig () { #{{{
 	if ($config{aggregate} && ! ($config{post_commit} && 
 	                             IkiWiki::commit_hook_enabled())) {
-		if (! IkiWiki::lockwiki(0)) {
-			debug("wiki is locked by another process, not aggregating");
-			exit 1;
-		}
-	
+		# See if any feeds need aggregation.
 		loadstate();
-		IkiWiki::loadindex();
-		aggregate();
-		expire();
-		savestate();
-		clearstate();
+		my @feeds=needsaggregate();
+		return unless @feeds;
+		if (! lockaggregate()) {
+			debug("an aggregation process is already running");
+			return;
+		}
+		# force a later rebuild of source pages
+		$IkiWiki::forcerebuild{$_->{sourcepage}}=1
+			foreach @feeds;
+
+		# Fork a child process to handle the aggregation.
+		# The parent process will then handle building the
+		# result. This avoids messy code to clear state
+		# accumulated while aggregating.
+		defined(my $pid = fork) or error("Can't fork: $!");
+		if (! $pid) {
+			IkiWiki::loadindex();
+
+			# Aggregation happens without the main wiki lock
+			# being held. This allows editing pages etc while
+			# aggregation is running.
+			aggregate(@feeds);
+
+			IkiWiki::lockwiki;
+			# Merge changes, since aggregation state may have
+			# changed on disk while the aggregation was happening.
+			mergestate();
+			expire();
+			savestate();
+			IkiWiki::unlockwiki;
+			exit 0;
+		}
+		waitpid($pid,0);
+		if ($?) {
+			error "aggregation failed with code $?";
+		}
 
-		IkiWiki::unlockwiki();
+		clearstate();
+		unlockaggregate();
 	}
 } #}}}
 
 sub needsbuild (@) { #{{{
 	my $needsbuild=shift;
 	
-	loadstate(); # if not already loaded
+	loadstate();
 
 	foreach my $feed (values %feeds) {
 		if (exists $pagesources{$feed->{sourcepage}} && 
 		    grep { $_ eq $pagesources{$feed->{sourcepage}} } @$needsbuild) {
-			# Mark all feeds originating on this page as removable;
-			# preprocess will unmark those that still exist.
-			remove_feeds($feed->{sourcepage});
+			# Mark all feeds originating on this page as 
+			# not yet seen; preprocess will unmark those that
+			# still exist.
+			markunseen($feed->{sourcepage});
 		}
 	}
 } # }}}
@@ -92,8 +121,7 @@ sub preprocess (@) { #{{{
 	$feed->{updateinterval}=defined $params{updateinterval} ? $params{updateinterval} * 60 : 15 * 60;
 	$feed->{expireage}=defined $params{expireage} ? $params{expireage} : 0;
 	$feed->{expirecount}=defined $params{expirecount} ? $params{expirecount} : 0;
-	delete $feed->{remove};
-	delete $feed->{expired};
+	delete $feed->{unseen};
 	$feed->{lastupdate}=0 unless defined $feed->{lastupdate};
 	$feed->{numposts}=0 unless defined $feed->{numposts};
 	$feed->{newposts}=0 unless defined $feed->{newposts};
@@ -123,16 +151,27 @@ sub delete (@) { #{{{
 	# Remove feed data for removed pages.
 	foreach my $file (@files) {
 		my $page=pagename($file);
-		remove_feeds($page);
+		markunseen($page);
+	}
+} #}}}
+
+sub markunseen ($) { #{{{
+	my $page=shift;
+
+	foreach my $id (keys %feeds) {
+		if ($feeds{$id}->{sourcepage} eq $page) {
+			$feeds{$id}->{unseen}=1;
+		}
 	}
 } #}}}
 
 my $state_loaded=0;
+
 sub loadstate () { #{{{
 	return if $state_loaded;
 	$state_loaded=1;
 	if (-e "$config{wikistatedir}/aggregate") {
-		open(IN, "<", "$config{wikistatedir}/aggregate") ||
+		open(IN, "$config{wikistatedir}/aggregate") ||
 			die "$config{wikistatedir}/aggregate: $!";
 		while (<IN>) {
 			$_=IkiWiki::possibly_foolish_untaint($_);
@@ -166,32 +205,13 @@ sub loadstate () { #{{{
 
 sub savestate () { #{{{
 	return unless $state_loaded;
+	garbage_collect();
 	eval q{use HTML::Entities};
 	error($@) if $@;
 	my $newfile="$config{wikistatedir}/aggregate.new";
 	my $cleanup = sub { unlink($newfile) };
-	open (OUT, ">", $newfile) || error("open $newfile: $!", $cleanup);
+	open (OUT, ">$newfile") || error("open $newfile: $!", $cleanup);
 	foreach my $data (values %feeds, values %guids) {
-		if ($data->{remove}) {
-			if ($data->{name}) {
-				foreach my $guid (values %guids) {
-					if ($guid->{feed} eq $data->{name}) {
-						$guid->{remove}=1;
-					}
-				}
-			}
-			else {
-				unlink pagefile($data->{page})
-					if exists $data->{page};
-			}
-			next;
-		}
-		elsif ($data->{expired} && exists $data->{page}) {
-			unlink pagefile($data->{page});
-			delete $data->{page};
-			delete $data->{md5};
-		}
-
 		my @line;
 		foreach my $field (keys %$data) {
 			if ($field eq "name" || $field eq "feed" ||
@@ -212,6 +232,63 @@ sub savestate () { #{{{
 		error("rename $newfile: $!", $cleanup);
 } #}}}
 
+sub garbage_collect () { #{{{
+	foreach my $name (keys %feeds) {
+		# remove any feeds that were not seen while building the pages
+		# that used to contain them
+		if ($feeds{$name}->{unseen}) {
+			delete $feeds{$name};
+		}
+	}
+
+	foreach my $guid (values %guids) {
+		# any guid whose feed is gone should be removed
+		if (! exists $feeds{$guid->{feed}}) {
+			unlink pagefile($guid->{page})
+				if exists $guid->{page};
+			delete $guids{$guid->{guid}};
+		}
+		# handle expired guids
+		elsif ($guid->{expired} && exists $guid->{page}) {
+			unlink pagefile($guid->{page});
+			delete $guid->{page};
+			delete $guid->{md5};
+		}
+	}
+} #}}}
+
+sub mergestate () { #{{{
+	# Load the current state in from disk, and merge into it
+	# values from the state in memory that might have changed
+	# during aggregation.
+	my %myfeeds=%feeds;
+	my %myguids=%guids;
+	clearstate();
+	loadstate();
+
+	# All that can change in feed state during aggregation is a few
+	# fields.
+	foreach my $name (keys %myfeeds) {
+		if (exists $feeds{$name}) {
+			foreach my $field (qw{message lastupdate numposts
+			                      newposts error}) {
+				$feeds{$name}->{$field}=$myfeeds{$name}->{$field};
+			}
+		}
+	}
+
+	# New guids can be created during aggregation.
+	# It's also possible that guids were removed from the on-disk state
+	# while the aggregation was in process. That would only happen if
+	# their feed was also removed, so any removed guids added back here
+	# will be garbage collected later.
+	foreach my $guid (keys %myguids) {
+		if (! exists $guids{$guid}) {
+			$guids{$guid}=$myguids{$guid};
+		}
+	}
+} #}}}
+
 sub clearstate () { #{{{
 	%feeds=();
 	%guids=();
@@ -249,7 +326,12 @@ sub expire () { #{{{
 	}
 } #}}}
 
-sub aggregate () { #{{{
+sub needsaggregate () { #{{{
+	return values %feeds if $config{rebuild};
+	return grep { time - $_->{lastupdate} >= $_->{updateinterval} } values %feeds;
+} #}}}
+
+sub aggregate (@) { #{{{
 	eval q{use XML::Feed};
 	error($@) if $@;
 	eval q{use URI::Fetch};
@@ -257,15 +339,12 @@ sub aggregate () { #{{{
 	eval q{use HTML::Entities};
 	error($@) if $@;
 
-	foreach my $feed (values %feeds) {
-		next unless $config{rebuild} || 
-			time - $feed->{lastupdate} >= $feed->{updateinterval};
+	foreach my $feed (@_) {
 		$feed->{lastupdate}=time;
 		$feed->{newposts}=0;
 		$feed->{message}=sprintf(gettext("processed ok at %s"),
 			displaytime($feed->{lastupdate}));
 		$feed->{error}=0;
-		$IkiWiki::forcerebuild{$feed->{sourcepage}}=1;
 
 		debug(sprintf(gettext("checking feed %s ..."), $feed->{name}));
 
@@ -473,18 +552,6 @@ sub htmlabs ($$) { #{{{
 	return $ret;
 } #}}}
 
-sub remove_feeds () { #{{{
-	my $page=shift;
-
-	my %removed;
-	foreach my $id (keys %feeds) {
-		if ($feeds{$id}->{sourcepage} eq $page) {
-			$feeds{$id}->{remove}=1;
-			$removed{$id}=1;
-		}
-	}
-} #}}}
-
 sub pagefile ($) { #{{{
 	my $page=shift;