--- /dev/null
+# vim: ft=perl
+# Blosxom Plugin: entries_cache_meta
+# Author(s): Jason Thaxter <sseye@ahab.com>
+# Version: 0.6
+
+package entries_cache_meta;
+
+# --- Configurable variables -----
+
+#
+# Caching variables
+#
+
+# How many minutes delay before entries are re-indexed?
+# (In minutes)
+# default: 15
+# zero means never auto-reindex
+$cache_period;
+
+# reindex password via query string to force re-indexing
+# default: none (re-index by time only)
+$reindex_passwd;
+
+# if true, this will warn when the cachefile can't be locked
+# default: off
+$write_lock_warn;
+
+#
+# Meta-related variables
+#
+
+# What prefix should I expect prepended to each meta tag?
+# default: meta-
+$meta_prefix;
+
+# If set, this meta variable will enable you to set modification times
+# e.g.:
+# meta-last_modified: 2003/01/12 10:33:33
+# see pod docs re: time format
+# default: mtime
+$meta_mtime;
+
+# enabled
+# default: 1
+# set to zero to disable this plugin
+# good for use w/ config plugin
+$enabled;
+
+# --------------------------------
+
+# defaults
+$cache_period = 15 if not defined $cache_period;
+$meta_prefix ||= 'meta-';
+$meta_mtime = 'mtime' unless defined $meta_mtime;
+$enabled = 1 unless defined $enabled;
+
+# standard perl modules
+use Fcntl qw(:DEFAULT :flock);
+use File::stat;
+use File::Find;
+use Data::Dumper;
+
+# standard for blosxom
+use CGI qw/:standard/;
+
+# we'll use Date::Parse if we have it
+$have_date_parse;
+eval { require Date::Parse; };
+if ($@) {
+ use Time::Local;
+}
+else {
+ $have_date_parse = 1;
+}
+
+%cache; # the cache
+%indexes = (); # nothing - we don't do static
+$reindex; # reindex or not
+*CACHE; # for the cache file
+$reindexed; # flag for "save cache"
+
+# the filename where the cache is stored
+$cachefile = "$blosxom::plugin_state_dir/entries_cache_meta";
+# and a temporary one while generating the cache
+$cache_tmp = "$cachefile.TMP";
+
+sub start {
+
+ return 0 if ( not $enabled or param('-all') );
+
+ # Read cache and reindex if failed or otherwise directed
+ (
+ (
+ not( $reindex_passwd and param('reindex') eq $reindex_passwd )
+ and not( $cache_period
+ and -f "$cachefile"
+ and stat($cachefile)->mtime lt( time() - $cache_period * 60 ) )
+ )
+ and ( open( MYCACHE, $cachefile )
+ and $index = join '', <MYCACHE>
+ and $index =~ /\$VAR1 = /
+ and eval($index)
+ and !$@
+ and %cache = %$VAR1
+ and close MYCACHE )
+
+ )
+ or $reindex = &lokkit( \*CACHE );
+
+ return 1;
+}
+
+sub entries {
+
+ # If we haven't flagged a need to re-index,
+ # copy from the cache
+ return sub {
+ my %files;
+ foreach ( keys %cache ) {
+
+ # copy into cache if the file exists
+ $files{$_} = $cache{$_}{mtime} if -f $_;
+ }
+ return ( \%files, \%indexes );
+ }
+ unless $reindex;
+
+ # otherwise, do a full reindex
+ return sub {
+
+ # Check to see if previously indexed files exist, and then rescan
+ # the datadir for any new files, while preserving the old times
+
+ for my $file ( keys %cache ) {
+ -f $file or do { $reindexed++; delete $cache{$file} };
+ }
+
+ find(
+ sub {
+
+ # easier to read.
+ $ffname = $File::Find::name;
+
+ # return if we're out of our depth
+ my $curr_depth = $File::Find::dir =~ tr[/][];
+ if ( $blosxom::depth and $curr_depth > $blosxom::depth ) {
+ $cache{$ffname}
+ and delete $cache{$ffname};
+ return;
+ }
+
+ # only bother for real entries
+ return
+ unless ( $ffname =~
+m!^$blosxom::datadir/(?:(.*)/)?(.+)\.$blosxom::file_extension$!
+ and $2 ne 'index'
+ and $2 !~ /^\./
+ and ( -r "$ffname" )
+ and ++$reindexed );
+
+ # process meta tags
+ if ( -T "$ffname" and open( FF, "<$ffname" ) ) {
+ $meta_title = <FF>;
+ chomp($meta_title);
+ $cache{$ffname}{title} = $meta_title;
+ while (<FF>) {
+
+ # get values
+ my ( $key, $value ) = m/^$meta_prefix(\w+)\s*:\s*(.+)$/;
+ last if not $key;
+
+ # set values
+ if ( $key ne "$meta_mtime" ) {
+ $cache{$ffname}{$key} = $value;
+ }
+
+ # set modification time
+ # with a double negative (hey)
+ else {
+ if ($have_date_parse) {
+ $time = Date::Parse::str2time($value);
+ }
+ elsif (
+ my ( $yr, $mo, $day, $hr, $min, $sec, $tz ) = (
+ $value =~
+m! (\d{4}) [/\:\-] (\d{2}) [/\:\-] (\d{2}) \s+
+ (\d{2}) : (\d{2}) : (\d{2})
+ \s*((UTC|GMT)*)!x
+ )
+ )
+ {
+ if ($tz) {
+ $time =
+ timegm( $sec, $min, $hr, $day, --$mo,
+ $yr );
+ }
+ else {
+ $time =
+ timelocal( $sec, $min, $hr, $day, --$mo,
+ $yr );
+ }
+ }
+ else {
+ warn "unparseable time in $ffname: $value";
+ }
+ $cache{$ffname}{mtime} = $time;
+ }
+ }
+ close FF;
+ }
+ else {
+ warn "couldn't open entry ($ffname): $!";
+ }
+
+ # If we have no meta mtime and no cached time,
+ # stat the file and store it.
+ if ( $cache{$ffname}{mtime} ) {
+ $files{$ffname} = $cache{$ffname}{mtime};
+ }
+ else { # make sure blosxom behaves normally
+ $files{$ffname} = stat($ffname)->mtime;
+ $cache{$ffname}{mtime} = $files{$ffname};
+ }
+
+ # show or not to show future entries
+ if ( not $blosxom::show_future_entries
+ and $files{$ffname} > time() )
+ {
+ delete $files{$ffname} and return;
+ }
+
+ },
+ $blosxom::datadir
+ );
+
+ return ( \%files, \%indexes ); # indexes is bogus: we don't do static
+ }
+}
+
+# put the stuff into $meta:: namespace for story rendering
+# and trim meta tags out of our story
+sub story {
+ my ( $pkg, $path, $filename, $story_ref, $title_ref, $body_ref ) = @_;
+
+ # first, load up our cached meta values
+ foreach my $key ( keys %{ $cache{$filename} } ) {
+ ${"meta::$key"} = $cache{$filename}{$key};
+ }
+
+ # next, remove any meta tags from the body
+ my ( $body, $in_body );
+ foreach ( split /\n/, $$body_ref ) {
+ if ($in_body) {
+ $body .= "$_\n";
+ }
+ elsif (/^$meta_prefix(\w+)\s*:\s*(.+)$/) {
+ ;
+ }
+ else {
+ $in_body = 1;
+ $body .= "$_\n";
+ }
+ }
+
+ $$body_ref = $body;
+
+ return 1;
+}
+
+# save cache - as late as possible
+# this gives other plugins a chance to alter values
+# or, forbid us from caching them!
+sub end {
+ &stuffit( \*CACHE, Dumper \%cache ) if ($reindexed);
+ 1;
+}
+
+#####################################################################
+# Internal subs
+#
+
+# Reserve file for writing
+sub lokkit {
+ local *FH = shift;
+
+ # open it
+ my $umask = umask 002; # group-write is useful
+ sysopen( FH, "$cache_tmp", O_RDWR | O_CREAT )
+ or ( warn "can't open file $cache_tmp: $!" and return );
+ umask $umask; # restore so it doesn't affect other plugins
+
+ # lock file
+ flock( FH, LOCK_EX | LOCK_NB )
+ or ( close FH
+ and ( not $write_lock_warn or warn "can't lock file: $!" )
+ and return );
+
+ return 1;
+}
+
+# Write and release file
+sub stuffit {
+ local *FH = shift;
+ local $contents = shift;
+
+ my $err;
+ print FH $contents or $err = "can't write cache $cache_tmp: $!";
+ flock( FH, LOCK_UN ) or $err = "can't unlock cache $cache_tmp: $!";
+ close FH or $err = "can't close cache $cache_tmp: $!";
+
+ if ( not $err ) {
+ rename "$cache_tmp", $cachefile
+ or warn "Error installing cache $cache_tmp: $!";
+ }
+ else {
+ warn $err;
+ unlink "$cache_tmp";
+ }
+}
+
+1;
+
+__END__
+
+=head1 NAME - entries_cache_meta
+
+Blosxom Plug-in: entries_cache_meta
+
+=head1 DESCRIPTION
+
+The entries_cache_meta plugin is Yet Another Caching Plugin, with some
+additional features, notably meta-tagging.
+
+By combining the meta-tag functionality with the entries cache, it becomes
+possible to write or use plugins that access meta-values outside the C<story>
+hook. For example, you could use this plugin to write another one showing the
+most recent entry for each author defined in meta tags.
+
+Additionally, it makes use of file locking to avoid from re-indexing if another
+request already has re-indexing in progress. Simultaneous re-indexing could
+corrupt the cache file, or bog down the server with redundant, expensive tasks;
+the larger and busier the site, the more likely these problems. For added
+security, you must supply a password if you want to force re-indexing via query
+string; this prevents any Blosxom-savvy user from forcing a re-index on your
+site.
+
+=head1 USAGE
+
+A properly permissioned $plugin_state_dir is required. Configuration is
+optional, but there are a few useful configuration variables.
+
+=over 4
+
+=item $cache_period
+
+How often, in minutes, to reindex automatically. If set to zero, re-indexing will never
+be automatic.
+
+=item $reindex_passwd
+
+What query string password forces reindex. You can force a scan by appending a
+query string, e.g. C<?reindex=mypassword> to the end of the url. This will
+also cause meta tags to be updated. However, for security's sake, you must
+set the password in the configuration to use this.
+
+=item $write_lock_warn
+
+Send a warning to the error log when it can't get a write-lock on the cache
+file. This is mostly useful for verifying that write-locking actually does
+something.
+
+=item $meta_prefix
+
+What prefix marks meta variable names. Defaults to C<meta->. An empty string
+should be permitted, but currently it isn't.
+
+=item $meta_mtime
+
+The name of the meta-property for file modification times. If this property is
+present in a given entry, it will override the modification time of the file as
+the entry's time. The default value is "mtime".
+
+The format of the time is obviously important: it can be either
+
+ meta-mtime: YYYY/MM/DD HH:MM:SS [UTC|GMT]
+
+or, if Date::Parse is present, any format parseable by that module. Either way,
+unparseable dates are simply ignored as if the property was not present. This
+feature may be disabled by setting it to an empty string.
+
+=back
+
+=head1 VERSION
+
+Version 0.6
+
+=head1 AUTHOR
+
+Jason Thaxter <sseye@ahab.com>
+
+This plugin is now maintained by the Blosxom Sourceforge Team,
+<blosxom-devel@lists.sourceforge.net>.
+
+=head1 SEE ALSO
+
+Blosxom Home/Docs/Licensing: http://blosxom.sourceforge.net
+
+Blosxom Plugin Docs: http://blosxom.sourceforge.net/documentation/users/plugins.html
+
+=head1 BUGS
+
+It doesn't currently work in static mode, in part because the premise of static
+mode is to be a performance benefit all on its own. Also because I don't use
+static mode and I'm lazy.
+
+Please send bug reports and feedback to the Blosxom development mailing list
+<blosxom-devel@lists.sourceforge.net>.
+
+=head1 LICENSE
+
+entries_cache_meta plugin
+Copyright 2004, Jason Thaxter
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
projects / matthijs / upstream / blosxom-plugins.git / commitdiff