IkiWiki/Plugin/aggregate.pm

   1 #!/usr/bin/perl
   2 # Blog aggregation plugin.
   3 package IkiWiki::Plugin::aggregate;
   4
   5 use warnings;
   6 use strict;
   7 use IkiWiki 2.00;
   8 use HTML::Entities;
   9 use HTML::Parser;
  10 use HTML::Tagset;
  11 use URI;
  12 use open qw{:utf8 :std};
  13
  14 my %feeds;
  15 my %guids;
  16
  17 sub import { #{{{
  18         hook(type => "getopt", id => "aggregate", call => \&getopt);
  19         hook(type => "checkconfig", id => "aggregate", call => \&checkconfig);
  20         hook(type => "needsbuild", id => "aggregate", call => \&needsbuild);
  21         hook(type => "preprocess", id => "aggregate", call => \&preprocess);
  22         hook(type => "delete", id => "aggregate", call => \&delete);
  23         hook(type => "savestate", id => "aggregate", call => \&savestate);
  24 } # }}}
  25
  26 sub getopt () { #{{{
  27         eval q{use Getopt::Long};
  28         error($@) if $@;
  29         Getopt::Long::Configure('pass_through');
  30         GetOptions("aggregate" => \$config{aggregate});
  31 } #}}}
  32
  33 sub checkconfig () { #{{{
  34         if ($config{aggregate} && ! ($config{post_commit} &&
  35                                      IkiWiki::commit_hook_enabled())) {
  36                 # See if any feeds need aggregation.
  37                 loadstate();
  38                 my @feeds=needsaggregate();
  39                 return unless @feeds;
  40                 if (! lockaggregate()) {
  41                         debug("an aggregation process is already running");
  42                         return;
  43                 }
  44                 # force a later rebuild of source pages
  45                 $IkiWiki::forcerebuild{$_->{sourcepage}}=1
  46                         foreach @feeds;
  47
  48                 # Fork a child process to handle the aggregation.
  49                 # The parent process will then handle building the
  50                 # result. This avoids messy code to clear state
  51                 # accumulated while aggregating.
  52                 defined(my $pid = fork) or error("Can't fork: $!");
  53                 if (! $pid) {
  54                         IkiWiki::loadindex();
  55
  56                         # Aggregation happens without the main wiki lock
  57                         # being held. This allows editing pages etc while
  58                         # aggregation is running.
  59                         aggregate(@feeds);
  60
  61                         IkiWiki::lockwiki;
  62                         # Merge changes, since aggregation state may have
  63                         # changed on disk while the aggregation was happening.
  64                         mergestate();
  65                         expire();
  66                         savestate();
  67                         IkiWiki::unlockwiki;
  68                         exit 0;
  69                 }
  70                 waitpid($pid,0);
  71                 if ($?) {
  72                         error "aggregation failed with code $?";
  73                 }
  74
  75                 clearstate();
  76                 unlockaggregate();
  77         }
  78 } #}}}
  79
  80 sub needsbuild (@) { #{{{
  81         my $needsbuild=shift;
  82
  83         loadstate();
  84
  85         foreach my $feed (values %feeds) {
  86                 if (exists $pagesources{$feed->{sourcepage}} &&
  87                     grep { $_ eq $pagesources{$feed->{sourcepage}} } @$needsbuild) {
  88                         # Mark all feeds originating on this page as
  89                         # not yet seen; preprocess will unmark those that
  90                         # still exist.
  91                         markunseen($feed->{sourcepage});
  92                 }
  93         }
  94 } # }}}
  95
  96 sub preprocess (@) { #{{{
  97         my %params=@_;
  98
  99         foreach my $required (qw{name url}) {
 100                 if (! exists $params{$required}) {
 101                         return "[[aggregate ".sprintf(gettext("missing %s parameter"), $required)."]]";
 102                 }
 103         }
 104
 105         my $feed={};
 106         my $name=$params{name};
 107         if (exists $feeds{$name}) {
 108                 $feed=$feeds{$name};
 109         }
 110         else {
 111                 $feeds{$name}=$feed;
 112         }
 113         $feed->{name}=$name;
 114         $feed->{sourcepage}=$params{page};
 115         $feed->{url}=$params{url};
 116         my $dir=exists $params{dir} ? $params{dir} : $params{page}."/".IkiWiki::titlepage($params{name});
 117         $dir=~s/^\/+//;
 118         ($dir)=$dir=~/$config{wiki_file_regexp}/;
 119         $feed->{dir}=$dir;
 120         $feed->{feedurl}=defined $params{feedurl} ? $params{feedurl} : "";
 121         $feed->{updateinterval}=defined $params{updateinterval} ? $params{updateinterval} * 60 : 15 * 60;
 122         $feed->{expireage}=defined $params{expireage} ? $params{expireage} : 0;
 123         $feed->{expirecount}=defined $params{expirecount} ? $params{expirecount} : 0;
 124         delete $feed->{unseen};
 125         $feed->{lastupdate}=0 unless defined $feed->{lastupdate};
 126         $feed->{numposts}=0 unless defined $feed->{numposts};
 127         $feed->{newposts}=0 unless defined $feed->{newposts};
 128         $feed->{message}=gettext("new feed") unless defined $feed->{message};
 129         $feed->{error}=0 unless defined $feed->{error};
 130         $feed->{tags}=[];
 131         while (@_) {
 132                 my $key=shift;
 133                 my $value=shift;
 134                 if ($key eq 'tag') {
 135                         push @{$feed->{tags}}, $value;
 136                 }
 137         }
 138
 139         return "<a href=\"".$feed->{url}."\">".$feed->{name}."</a>: ".
 140                ($feed->{error} ? "<em>" : "").$feed->{message}.
 141                ($feed->{error} ? "</em>" : "").
 142                " (".$feed->{numposts}." ".gettext("posts").
 143                ($feed->{newposts} ? "; ".$feed->{newposts}.
 144                                     " ".gettext("new") : "").
 145                ")";
 146 } # }}}
 147
 148 sub delete (@) { #{{{
 149         my @files=@_;
 150
 151         # Remove feed data for removed pages.
 152         foreach my $file (@files) {
 153                 my $page=pagename($file);
 154                 markunseen($page);
 155         }
 156 } #}}}
 157
 158 sub markunseen ($) { #{{{
 159         my $page=shift;
 160
 161         foreach my $id (keys %feeds) {
 162                 if ($feeds{$id}->{sourcepage} eq $page) {
 163                         $feeds{$id}->{unseen}=1;
 164                 }
 165         }
 166 } #}}}
 167
 168 my $state_loaded=0;
 169
 170 sub loadstate () { #{{{
 171         return if $state_loaded;
 172         $state_loaded=1;
 173         if (-e "$config{wikistatedir}/aggregate") {
 174                 open(IN, "$config{wikistatedir}/aggregate") ||
 175                         die "$config{wikistatedir}/aggregate: $!";
 176                 while (<IN>) {
 177                         $_=IkiWiki::possibly_foolish_untaint($_);
 178                         chomp;
 179                         my $data={};
 180                         foreach my $i (split(/ /, $_)) {
 181                                 my ($field, $val)=split(/=/, $i, 2);
 182                                 if ($field eq "name" || $field eq "feed" ||
 183                                     $field eq "guid" || $field eq "message") {
 184                                         $data->{$field}=decode_entities($val, " \t\n");
 185                                 }
 186                                 elsif ($field eq "tag") {
 187                                         push @{$data->{tags}}, $val;
 188                                 }
 189                                 else {
 190                                         $data->{$field}=$val;
 191                                 }
 192                         }
 193
 194                         if (exists $data->{name}) {
 195                                 $feeds{$data->{name}}=$data;
 196                         }
 197                         elsif (exists $data->{guid}) {
 198                                 $guids{$data->{guid}}=$data;
 199                         }
 200                 }
 201
 202                 close IN;
 203         }
 204 } #}}}
 205
 206 sub savestate () { #{{{
 207         return unless $state_loaded;
 208         garbage_collect();
 209         eval q{use HTML::Entities};
 210         error($@) if $@;
 211         my $newfile="$config{wikistatedir}/aggregate.new";
 212         my $cleanup = sub { unlink($newfile) };
 213         open (OUT, ">$newfile") || error("open $newfile: $!", $cleanup);
 214         foreach my $data (values %feeds, values %guids) {
 215                 my @line;
 216                 foreach my $field (keys %$data) {
 217                         if ($field eq "name" || $field eq "feed" ||
 218                             $field eq "guid" || $field eq "message") {
 219                                 push @line, "$field=".encode_entities($data->{$field}, " \t\n");
 220                         }
 221                         elsif ($field eq "tags") {
 222                                 push @line, "tag=$_" foreach @{$data->{tags}};
 223                         }
 224                         else {
 225                                 push @line, "$field=".$data->{$field};
 226                         }
 227                 }
 228                 print OUT join(" ", @line)."\n" || error("write $newfile: $!", $cleanup);
 229         }
 230         close OUT || error("save $newfile: $!", $cleanup);
 231         rename($newfile, "$config{wikistatedir}/aggregate") ||
 232                 error("rename $newfile: $!", $cleanup);
 233 } #}}}
 234
 235 sub garbage_collect () { #{{{
 236         foreach my $name (keys %feeds) {
 237                 # remove any feeds that were not seen while building the pages
 238                 # that used to contain them
 239                 if ($feeds{$name}->{unseen}) {
 240                         delete $feeds{$name};
 241                 }
 242         }
 243
 244         foreach my $guid (values %guids) {
 245                 # any guid whose feed is gone should be removed
 246                 if (! exists $feeds{$guid->{feed}}) {
 247                         unlink pagefile($guid->{page})
 248                                 if exists $guid->{page};
 249                         delete $guids{$guid->{guid}};
 250                 }
 251                 # handle expired guids
 252                 elsif ($guid->{expired} && exists $guid->{page}) {
 253                         unlink pagefile($guid->{page});
 254                         delete $guid->{page};
 255                         delete $guid->{md5};
 256                 }
 257         }
 258 } #}}}
 259
 260 sub mergestate () { #{{{
 261         # Load the current state in from disk, and merge into it
 262         # values from the state in memory that might have changed
 263         # during aggregation.
 264         my %myfeeds=%feeds;
 265         my %myguids=%guids;
 266         clearstate();
 267         loadstate();
 268
 269         # All that can change in feed state during aggregation is a few
 270         # fields.
 271         foreach my $name (keys %myfeeds) {
 272                 if (exists $feeds{$name}) {
 273                         foreach my $field (qw{message lastupdate numposts
 274                                               newposts error}) {
 275                                 $feeds{$name}->{$field}=$myfeeds{$name}->{$field};
 276                         }
 277                 }
 278         }
 279
 280         # New guids can be created during aggregation.
 281         # It's also possible that guids were removed from the on-disk state
 282         # while the aggregation was in process. That would only happen if
 283         # their feed was also removed, so any removed guids added back here
 284         # will be garbage collected later.
 285         foreach my $guid (keys %myguids) {
 286                 if (! exists $guids{$guid}) {
 287                         $guids{$guid}=$myguids{$guid};
 288                 }
 289         }
 290 } #}}}
 291
 292 sub clearstate () { #{{{
 293         %feeds=();
 294         %guids=();
 295         $state_loaded=0;
 296 } #}}}
 297
 298 sub expire () { #{{{
 299         foreach my $feed (values %feeds) {
 300                 next unless $feed->{expireage} || $feed->{expirecount};
 301                 my $count=0;
 302                 my %seen;
 303                 foreach my $item (sort { $IkiWiki::pagectime{$b->{page}} <=> $IkiWiki::pagectime{$a->{page}} }
 304                                   grep { exists $_->{page} && $_->{feed} eq $feed->{name} && $IkiWiki::pagectime{$_->{page}} }
 305                                   values %guids) {
 306                         if ($feed->{expireage}) {
 307                                 my $days_old = (time - $IkiWiki::pagectime{$item->{page}}) / 60 / 60 / 24;
 308                                 if ($days_old > $feed->{expireage}) {
 309                                         debug(sprintf(gettext("expiring %s (%s days old)"),
 310                                                 $item->{page}, int($days_old)));
 311                                         $item->{expired}=1;
 312                                 }
 313                         }
 314                         elsif ($feed->{expirecount} &&
 315                                $count >= $feed->{expirecount}) {
 316                                 debug(sprintf(gettext("expiring %s"), $item->{page}));
 317                                 $item->{expired}=1;
 318                         }
 319                         else {
 320                                 if (! $seen{$item->{page}}) {
 321                                         $seen{$item->{page}}=1;
 322                                         $count++;
 323                                 }
 324                         }
 325                 }
 326         }
 327 } #}}}
 328
 329 sub needsaggregate () { #{{{
 330         return values %feeds if $config{rebuild};
 331         return grep { time - $_->{lastupdate} >= $_->{updateinterval} } values %feeds;
 332 } #}}}
 333
 334 sub aggregate (@) { #{{{
 335         eval q{use XML::Feed};
 336         error($@) if $@;
 337         eval q{use URI::Fetch};
 338         error($@) if $@;
 339         eval q{use HTML::Entities};
 340         error($@) if $@;
 341
 342         foreach my $feed (@_) {
 343                 $feed->{lastupdate}=time;
 344                 $feed->{newposts}=0;
 345                 $feed->{message}=sprintf(gettext("processed ok at %s"),
 346                         displaytime($feed->{lastupdate}));
 347                 $feed->{error}=0;
 348
 349                 debug(sprintf(gettext("checking feed %s ..."), $feed->{name}));
 350
 351                 if (! length $feed->{feedurl}) {
 352                         my @urls=XML::Feed->find_feeds($feed->{url});
 353                         if (! @urls) {
 354                                 $feed->{message}=sprintf(gettext("could not find feed at %s"), $feed->{url});
 355                                 $feed->{error}=1;
 356                                 debug($feed->{message});
 357                                 next;
 358                         }
 359                         $feed->{feedurl}=pop @urls;
 360                 }
 361                 my $res=URI::Fetch->fetch($feed->{feedurl});
 362                 if (! $res) {
 363                         $feed->{message}=URI::Fetch->errstr;
 364                         $feed->{error}=1;
 365                         debug($feed->{message});
 366                         next;
 367                 }
 368                 if ($res->status == URI::Fetch::URI_GONE()) {
 369                         $feed->{message}=gettext("feed not found");
 370                         $feed->{error}=1;
 371                         debug($feed->{message});
 372                         next;
 373                 }
 374                 my $content=$res->content;
 375                 my $f=eval{XML::Feed->parse(\$content)};
 376                 if ($@) {
 377                         # One common cause of XML::Feed crashing is a feed
 378                         # that contains invalid UTF-8 sequences. Convert
 379                         # feed to ascii to try to work around.
 380                         $feed->{message}.=" ".sprintf(gettext("(invalid UTF-8 stripped from feed)"));
 381                         $content=Encode::decode_utf8($content);
 382                         $f=eval{XML::Feed->parse(\$content)};
 383                 }
 384                 if ($@) {
 385                         # Another possibility is badly escaped entities.
 386                         $feed->{message}.=" ".sprintf(gettext("(feed entities escaped)"));
 387                         $content=~s/\&(?!amp)(\w+);/&amp;$1;/g;
 388                         $content=Encode::decode_utf8($content);
 389                         $f=eval{XML::Feed->parse(\$content)};
 390                 }
 391                 if ($@) {
 392                         $feed->{message}=gettext("feed crashed XML::Feed!")." ($@)";
 393                         $feed->{error}=1;
 394                         debug($feed->{message});
 395                         next;
 396                 }
 397                 if (! $f) {
 398                         $feed->{message}=XML::Feed->errstr;
 399                         $feed->{error}=1;
 400                         debug($feed->{message});
 401                         next;
 402                 }
 403
 404                 foreach my $entry ($f->entries) {
 405                         add_page(
 406                                 feed => $feed,
 407                                 copyright => $f->copyright,
 408                                 title => defined $entry->title ? decode_entities($entry->title) : "untitled",
 409                                 link => $entry->link,
 410                                 content => defined $entry->content->body ? $entry->content->body : "",
 411                                 guid => defined $entry->id ? $entry->id : time."_".$feed->name,
 412                                 ctime => $entry->issued ? ($entry->issued->epoch || time) : time,
 413                         );
 414                 }
 415         }
 416 } #}}}
 417
 418 sub add_page (@) { #{{{
 419         my %params=@_;
 420
 421         my $feed=$params{feed};
 422         my $guid={};
 423         my $mtime;
 424         if (exists $guids{$params{guid}}) {
 425                 # updating an existing post
 426                 $guid=$guids{$params{guid}};
 427                 return if $guid->{expired};
 428         }
 429         else {
 430                 # new post
 431                 $guid->{guid}=$params{guid};
 432                 $guids{$params{guid}}=$guid;
 433                 $mtime=$params{ctime};
 434                 $feed->{numposts}++;
 435                 $feed->{newposts}++;
 436
 437                 # assign it an unused page
 438                 my $page=IkiWiki::titlepage($params{title});
 439                 # escape slashes and periods in title so it doesn't specify
 440                 # directory name or trigger ".." disallowing code.
 441                 $page=~s!([/.])!"__".ord($1)."__"!eg;
 442                 $page=$feed->{dir}."/".$page;
 443                 ($page)=$page=~/$config{wiki_file_regexp}/;
 444                 if (! defined $page || ! length $page) {
 445                         $page=$feed->{dir}."/item";
 446                 }
 447                 my $c="";
 448                 while (exists $IkiWiki::pagecase{lc $page.$c} ||
 449                        -e pagefile($page.$c)) {
 450                         $c++
 451                 }
 452
 453                 # Make sure that the file name isn't too long.
 454                 # NB: This doesn't check for path length limits.
 455                 my $max=POSIX::pathconf($config{srcdir}, &POSIX::_PC_NAME_MAX);
 456                 if (defined $max && length(htmlfn($page)) >= $max) {
 457                         $c="";
 458                         $page=$feed->{dir}."/item";
 459                         while (exists $IkiWiki::pagecase{lc $page.$c} ||
 460                                -e pagefile($page.$c)) {
 461                                 $c++
 462                         }
 463                 }
 464
 465                 $guid->{page}=$page;
 466                 debug(sprintf(gettext("creating new page %s"), $page));
 467         }
 468         $guid->{feed}=$feed->{name};
 469
 470         # To write or not to write? Need to avoid writing unchanged pages
 471         # to avoid unneccessary rebuilding. The mtime from rss cannot be
 472         # trusted; let's use a digest.
 473         eval q{use Digest::MD5 'md5_hex'};
 474         error($@) if $@;
 475         require Encode;
 476         my $digest=md5_hex(Encode::encode_utf8($params{content}));
 477         return unless ! exists $guid->{md5} || $guid->{md5} ne $digest || $config{rebuild};
 478         $guid->{md5}=$digest;
 479
 480         # Create the page.
 481         my $template=template("aggregatepost.tmpl", blind_cache => 1);
 482         $template->param(title => $params{title})
 483                 if defined $params{title} && length($params{title});
 484         $template->param(content => htmlescape(htmlabs($params{content}, $feed->{feedurl})));
 485         $template->param(name => $feed->{name});
 486         $template->param(url => $feed->{url});
 487         $template->param(copyright => $params{copyright})
 488                 if defined $params{copyright} && length $params{copyright};
 489         $template->param(permalink => urlabs($params{link}, $feed->{feedurl}))
 490                 if defined $params{link};
 491         if (ref $feed->{tags}) {
 492                 $template->param(tags => [map { tag => $_ }, @{$feed->{tags}}]);
 493         }
 494         writefile(htmlfn($guid->{page}), $config{srcdir},
 495                 $template->output);
 496
 497         # Set the mtime, this lets the build process get the right creation
 498         # time on record for the new page.
 499         utime $mtime, $mtime, pagefile($guid->{page})
 500                 if defined $mtime && $mtime <= time;
 501 } #}}}
 502
 503 sub htmlescape ($) { #{{{
 504         # escape accidental wikilinks and preprocessor stuff
 505         my $html=shift;
 506         $html=~s/(?<!\\)\[\[/\\\[\[/g;
 507         return $html;
 508 } #}}}
 509
 510 sub urlabs ($$) { #{{{
 511         my $url=shift;
 512         my $urlbase=shift;
 513
 514         URI->new_abs($url, $urlbase)->as_string;
 515 } #}}}
 516
 517 sub htmlabs ($$) { #{{{
 518         # Convert links in html from relative to absolute.
 519         # Note that this is a heuristic, which is not specified by the rss
 520         # spec and may not be right for all feeds. Also, see Debian
 521         # bug #381359.
 522         my $html=shift;
 523         my $urlbase=shift;
 524
 525         my $ret="";
 526         my $p = HTML::Parser->new(api_version => 3);
 527         $p->handler(default => sub { $ret.=join("", @_) }, "text");
 528         $p->handler(start => sub {
 529                 my ($tagname, $pos, $text) = @_;
 530                 if (ref $HTML::Tagset::linkElements{$tagname}) {
 531                         while (4 <= @$pos) {
 532                                 # use attribute sets from right to left
 533                                 # to avoid invalidating the offsets
 534                                 # when replacing the values
 535                                 my($k_offset, $k_len, $v_offset, $v_len) =
 536                                         splice(@$pos, -4);
 537                                 my $attrname = lc(substr($text, $k_offset, $k_len));
 538                                 next unless grep { $_ eq $attrname } @{$HTML::Tagset::linkElements{$tagname}};
 539                                 next unless $v_offset; # 0 v_offset means no value
 540                                 my $v = substr($text, $v_offset, $v_len);
 541                                 $v =~ s/^([\'\"])(.*)\1$/$2/;
 542                                 my $new_v=urlabs($v, $urlbase);
 543                                 $new_v =~ s/\"/&quot;/g; # since we quote with ""
 544                                 substr($text, $v_offset, $v_len) = qq("$new_v");
 545                         }
 546                 }
 547                 $ret.=$text;
 548         }, "tagname, tokenpos, text");
 549         $p->parse($html);
 550         $p->eof;
 551
 552         return $ret;
 553 } #}}}
 554
 555 sub pagefile ($) { #{{{
 556         my $page=shift;
 557
 558         return "$config{srcdir}/".htmlfn($page);
 559 } #}}}
 560
 561 sub htmlfn ($) { #{{{
 562         return shift().".".$config{htmlext};
 563 } #}}}
 564
 565 my $aggregatelock;
 566
 567 sub lockaggregate () { #{{{
 568         # Take an exclusive lock to prevent multiple concurrent aggregators.
 569         # Returns true if the lock was aquired.
 570         if (! -d $config{wikistatedir}) {
 571                 mkdir($config{wikistatedir});
 572         }
 573         open($aggregatelock, '>', "$config{wikistatedir}/aggregatelock") ||
 574                 error ("cannot open to $config{wikistatedir}/aggregatelock: $!");
 575         if (! flock($aggregatelock, 2 | 4)) { # LOCK_EX | LOCK_NB
 576                 close($aggregatelock) || error("failed closing aggregatelock: $!");
 577                 return 0;
 578         }
 579         return 1;
 580 } #}}}
 581
 582 sub unlockaggregate () { #{{{
 583         return close($aggregatelock) if $aggregatelock;
 584         return;
 585 } #}}}
 586
 587 1