root/main/trunk/greenstone2/perllib/plugins/DirectoryPlugin.pm @ 21315

Revision 21315, 20.6 KB (checked in by kjdon, 11 years ago)

remove_one now returns a value

  • Property svn:executable set to *
  • Property svn:keywords set to Author Date Id Revision
Line 
1###########################################################################
2#
3# DirectoryPlugin.pm --
4# A component of the Greenstone digital library software
5# from the New Zealand Digital Library Project at the
6# University of Waikato, New Zealand.
7#
8# Copyright (C) 1999 New Zealand Digital Library Project
9#
10# This program is free software; you can redistribute it and/or modify
11# it under the terms of the GNU General Public License as published by
12# the Free Software Foundation; either version 2 of the License, or
13# (at your option) any later version.
14#
15# This program is distributed in the hope that it will be useful,
16# but WITHOUT ANY WARRANTY; without even the implied warranty of
17# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18# GNU General Public License for more details.
19#
20# You should have received a copy of the GNU General Public License
21# along with this program; if not, write to the Free Software
22# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23#
24###########################################################################
25
26# DirectoryPlugin is a plugin which recurses through directories processing
27# each file it finds - which basically means passing it down the plugin
28# pipeline
29
30package DirectoryPlugin;
31
32use PrintInfo;
33use plugin;
34use util;
35use metadatautil;
36
37use File::Basename;
38use strict;
39no strict 'refs';
40no strict 'subs';
41
42use Encode;
43
44BEGIN {
45    @DirectoryPlugin::ISA = ('PrintInfo');
46}
47
48my $arguments =
49    [ { 'name' => "block_exp",
50    'desc' => "{BasePlugin.block_exp}",
51    'type' => "regexp",
52    'deft' => &get_default_block_exp(),
53    'reqd' => "no" },
54      # this option has been deprecated. leave it here for now so we can warn people not to use it
55      { 'name' => "use_metadata_files",
56    'desc' => "{DirectoryPlugin.use_metadata_files}",
57    'type' => "flag",
58    'reqd' => "no",
59    'hiddengli' => "yes" },
60      { 'name' => "recheck_directories",
61    'desc' => "{DirectoryPlugin.recheck_directories}",
62    'type' => "flag",
63    'reqd' => "no" } ];
64   
65my $options = { 'name'     => "DirectoryPlugin",
66        'desc'     => "{DirectoryPlugin.desc}",
67        'abstract' => "no",
68        'inherits' => "yes",
69        'args'     => $arguments };
70
71sub new {
72    my ($class) = shift (@_);
73    my ($pluginlist,$inputargs,$hashArgOptLists) = @_;
74    push(@$pluginlist, $class);
75
76    push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});
77    push(@{$hashArgOptLists->{"OptList"}},$options);
78
79    my $self = new PrintInfo($pluginlist, $inputargs, $hashArgOptLists);
80   
81    if ($self->{'info_only'}) {
82    # don't worry about any options or initialisations etc
83    return bless $self, $class;
84    }
85
86    # we have left this option in so we can warn people who are still using it
87    if ($self->{'use_metadata_files'}) {
88    die "ERROR: DirectoryPlugin -use_metadata_files option has been deprecated. Please remove the option and add MetadataXMLPlug to your plugin list instead!\n";
89    }
90   
91    $self->{'num_processed'} = 0;
92    $self->{'num_not_processed'} = 0;
93    $self->{'num_blocked'} = 0;
94    $self->{'num_archives'} = 0;
95
96    $self->{'subdir_extrametakeys'} = {};
97
98    return bless $self, $class;
99}
100
101# called once, at the start of processing
102sub init {
103    my $self = shift (@_);
104    my ($verbosity, $outhandle, $failhandle) = @_;
105
106    # verbosity is passed through from the processor
107    $self->{'verbosity'} = $verbosity;
108
109    # as are the outhandle and failhandle
110    $self->{'outhandle'} = $outhandle if defined $outhandle;
111    $self->{'failhandle'} = $failhandle;
112
113}
114
115# called once, after all passes have finished
116sub deinit {
117    my ($self) = @_;
118
119}
120
121# called at the beginning of each plugin pass (import has one, building has many)
122sub begin {
123    my $self = shift (@_);
124    my ($pluginfo, $base_dir, $processor, $maxdocs) = @_;
125
126    my $proc_package_name = ref $processor;
127
128    if ($proc_package_name !~ /buildproc$/ && $self->{'incremental'} == 1) {
129
130    # Only lookup timestamp info for import.pl, and only if incremental is set
131
132    my $output_dir = $processor->getoutputdir();
133##  my $archives_inf = &util::filename_cat($output_dir,"archives.inf");
134    my $doc_db = "archiveinf-doc.gdb";
135        my $archives_inf = &util::filename_cat($output_dir,$doc_db);
136
137    if ( -e $archives_inf ) {
138        $self->{'inf_timestamp'} = -M $archives_inf;
139    }
140    }
141}
142
143sub remove_all {
144    my $self = shift (@_);
145    my ($pluginfo, $base_dir, $processor, $maxdocs) = @_;
146
147}
148
149
150sub remove_one {
151    my $self = shift (@_);
152    my ($file, $oids, $archivedir) = @_;
153    return undef; # this will never be called for directories (will it??)
154
155}
156
157
158# called at the end of each plugin pass
159sub end {
160    my ($self) = shift (@_);
161
162}
163
164
165
166# return 1 if this class might recurse using $pluginfo
167sub is_recursive {
168    my $self = shift (@_);
169   
170    return 1;
171}
172
173sub get_default_block_exp {
174    my $self = shift (@_);
175   
176    return '(?i)(CVS|\.svn|Thumbs\.db|OIDcount|~)$';
177}
178
179sub check_directory_path {
180
181    my $self = shift(@_);
182    my ($dirname) = @_;
183   
184    return undef unless (-d $dirname);
185
186    return 0 if ($self->{'block_exp'} ne "" && $dirname =~ /$self->{'block_exp'}/);
187
188    my $outhandle = $self->{'outhandle'};
189   
190    # check to make sure we're not reading the archives or index directory
191    my $gsdlhome = quotemeta($ENV{'GSDLHOME'});
192    if ($dirname =~ m/^$gsdlhome\/.*?\/import.*?\/(archives|index)$/) {
193    print $outhandle "DirectoryPlugin: $dirname appears to be a reference to a Greenstone collection, skipping.\n";
194        return 0;
195    }
196   
197    # check to see we haven't got a cyclic path...
198    if ($dirname =~ m%(/.*){,41}%) {
199    print $outhandle "DirectoryPlugin: $dirname is 40 directories deep, is this a recursive path? if not increase constant in DirectoryPlugin.pm.\n";
200    return 0;
201    }
202   
203    # check to see we haven't got a cyclic path...
204    if ($dirname =~ m%.*?import/(.+?)/import/\1.*%) {
205    print $outhandle "DirectoryPlugin: $dirname appears to be in a recursive loop...\n";
206    return 0;
207    }
208
209    return 1;
210}
211
212# this may be called more than once
213sub sort_out_associated_files {
214
215    my $self = shift (@_);
216    my ($block_hash) = @_;
217    if (!scalar (keys %{$block_hash->{'shared_fileroot'}})) {
218    return;
219    }
220
221    $self->{'assocfile_info'} = {} unless defined $self->{'assocfile_info'};
222    my $metadata = $self->{'assocfile_info'};
223    foreach my $prefix (keys %{$block_hash->{'shared_fileroot'}}) {
224    my $record = $block_hash->{'shared_fileroot'}->{$prefix};
225
226    my $tie_to = $record->{'tie_to'};
227    my $exts = $record->{'exts'};
228   
229    if ((defined $tie_to) && (scalar (keys %$exts) > 0)) {
230        # set up fileblocks and assocfile_tobe
231        my $base_file = "$prefix$tie_to";
232        $metadata->{$base_file} = {} unless defined $metadata->{$base_file};
233        my $base_file_metadata = $metadata->{$base_file};
234       
235        $base_file_metadata->{'gsdlassocfile_tobe'} = [] unless defined $base_file_metadata->{'gsdlassocfile_tobe'};
236        my $assoc_tobe = $base_file_metadata->{'gsdlassocfile_tobe'};
237        foreach my $e (keys %$exts) {
238        # block the file
239        $block_hash->{'file_blocks'}->{"$prefix$e"} = 1;
240        # set up as an associatd file
241        print STDERR "  $self->{'plugin_type'}: Associating $prefix$e with $tie_to version\n";
242        my $mime_type = ""; # let system auto detect this
243        push(@$assoc_tobe,"$prefix$e:$mime_type:");
244
245        }
246    }
247    } # foreach record
248
249    $block_hash->{'shared_fileroot'} = undef;
250    $block_hash->{'shared_fileroot'} = {};
251
252}
253
254
255# do block exp OR special blocking ???
256
257sub file_is_blocked {
258    my $self = shift (@_);
259    my ($block_hash, $filename_full_path) = @_;
260
261    if (defined $block_hash->{'file_blocks'}->{$filename_full_path}) {
262    $self->{'num_blocked'} ++;
263    return 1;
264    }
265    # check Directory plugin's own block_exp
266    if ($self->{'block_exp'} ne "" && $filename_full_path =~ /$self->{'block_exp'}/) {
267    $self->{'num_blocked'} ++;
268    return 1; # blocked
269    }
270    return 0;
271}
272
273
274
275sub file_block_read {
276    my $self = shift (@_);
277    my ($pluginfo, $base_dir, $file, $block_hash, $metadata, $gli) = @_;
278
279    my $outhandle = $self->{'outhandle'};
280    my $verbosity = $self->{'verbosity'};
281   
282    # Calculate the directory name and ensure it is a directory and
283    # that it is not explicitly blocked.
284    my $dirname = $file;
285    $dirname = &util::filename_cat ($base_dir, $file) if $base_dir =~ /\w/;
286
287    my $directory_ok = $self->check_directory_path($dirname);
288    return $directory_ok unless (defined $directory_ok && $directory_ok == 1);
289
290    print $outhandle "Global file scan checking directory: $dirname\n";
291
292    $block_hash->{'all_files'} = {} unless defined $block_hash->{'all_files'};
293    $block_hash->{'metadata_files'} = {} unless defined $block_hash->{'metadata_files'};
294
295    $block_hash->{'file_blocks'} = {} unless defined $block_hash->{'file_blocks'};
296    $block_hash->{'shared_fileroot'} = {} unless defined $block_hash->{'shared_fileroot'};
297
298     # Recur over directory contents.
299    my (@dir, $subfile);
300    #my $count = 0;
301   
302    print $outhandle "DirectoryPlugin block: getting directory $dirname\n" if ($verbosity > 2);
303   
304    # find all the files in the directory
305    if (!opendir (DIR, $dirname)) {
306    if ($gli) {
307        print STDERR "<ProcessingError n='$file' r='Could not read directory $dirname'>\n";
308    }
309    print $outhandle "DirectoryPlugin: WARNING - couldn't read directory $dirname\n";
310    return -1; # error in processing
311    }
312    @dir = readdir (DIR);
313    closedir (DIR);
314   
315    for (my $i = 0; $i < scalar(@dir); $i++) {
316    my $subfile = $dir[$i];
317    my $this_file_base_dir = $base_dir;
318    next if ($subfile =~ m/^\.\.?$/);
319
320    # Recursively read each $subfile
321    print $outhandle "DirectoryPlugin block recurring: $subfile\n" if ($verbosity > 2);
322   
323    #$count += &plugin::file_block_read ($pluginfo, $this_file_base_dir,
324    &plugin::file_block_read ($pluginfo, $this_file_base_dir,
325                  &util::filename_cat($file, $subfile),
326                  $block_hash, $metadata, $gli);
327   
328    }
329    $self->sort_out_associated_files($block_hash);
330    #return $count;
331   
332}
333
334# We don't do metadata_read
335sub metadata_read {
336    my $self = shift (@_);
337    my ($pluginfo, $base_dir, $file, $block_hash,
338    $extrametakeys, $extrametadata, $extrametafile,
339    $processor, $maxdocs, $gli) = @_;
340
341    return undef;
342}
343
344
345# return number of files processed, undef if can't process
346# Note that $base_dir might be "" and that $file might
347# include directories
348
349# This function passes around metadata hash structures.  Metadata hash
350# structures are hashes that map from a (scalar) key (the metadata element
351# name) to either a scalar metadata value or a reference to an array of
352# such values.
353
354sub read {
355    my $self = shift (@_);
356    my ($pluginfo, $base_dir, $file, $block_hash, $in_metadata, $processor, $maxdocs, $total_count, $gli) = @_;
357
358    my $outhandle = $self->{'outhandle'};
359    my $verbosity = $self->{'verbosity'};
360   
361    # Calculate the directory name and ensure it is a directory and
362    # that it is not explicitly blocked.
363    my $dirname;
364    if ($file eq "") {
365    $dirname = $base_dir;
366    } else {
367    $dirname = $file;
368    $dirname = &util::filename_cat ($base_dir, $file) if $base_dir =~ /\w/;
369    }
370
371    my $directory_ok = $self->check_directory_path($dirname);
372    return $directory_ok unless (defined $directory_ok && $directory_ok == 1);
373       
374    if (($verbosity > 2) && ((scalar keys %$in_metadata) > 0)) {
375        print $outhandle "DirectoryPlugin: metadata passed in: ",
376    join(", ", keys %$in_metadata), "\n";
377    }
378   
379
380    # Recur over directory contents.
381    my (@dir, $subfile);
382    my $count = 0;
383   
384    print $outhandle "DirectoryPlugin read: getting directory $dirname\n" if ($verbosity > 2);
385   
386    # find all the files in the directory
387    if (!opendir (DIR, $dirname)) {
388    if ($gli) {
389        print STDERR "<ProcessingError n='$file' r='Could not read directory $dirname'>\n";
390    }
391    print $outhandle "DirectoryPlugin: WARNING - couldn't read directory $dirname\n";
392    return -1; # error in processing
393    }
394    @dir = readdir (DIR);
395    closedir (DIR);
396
397    # Re-order the files in the list so any directories ending with .all are moved to the end
398    for (my $i = scalar(@dir) - 1; $i >= 0; $i--) {
399    if (-d &util::filename_cat($dirname, $dir[$i]) && $dir[$i] =~ /\.all$/) {
400        push(@dir, splice(@dir, $i, 1));
401    }
402    }
403
404    # setup the metadata structures. we do a metadata_read pass to see if there is any additional metadata, then pass it to read
405   
406    my $additionalmetadata = 0;      # is there extra metadata available?
407    my %extrametadata;               # maps from filespec to extra metadata keys
408    my %extrametafile;               # maps from filespec to the metadata.xml (or similar) file it came from
409    my @extrametakeys;               # keys of %extrametadata in order read
410
411
412    my $os_dirsep = &util::get_os_dirsep();
413    my $dirsep    = &util::get_dirsep();
414    my $base_dir_regexp = $base_dir;
415    $base_dir_regexp =~ s/\//$os_dirsep/g;
416    my $local_dirname = $dirname;
417    $local_dirname =~ s/^$base_dir_regexp($os_dirsep)//;
418    $local_dirname .= $dirsep;
419   
420    if (defined $self->{'subdir_extrametakeys'}->{$local_dirname}) {
421    my $extrakeys = $self->{'subdir_extrametakeys'}->{$local_dirname};
422    foreach my $ek (@$extrakeys) {
423        my $extrakeys_re  = $ek->{'re'};
424        my $extrakeys_md  = $ek->{'md'};
425        my $extrakeys_mf  = $ek->{'mf'};
426        push(@extrametakeys,$extrakeys_re);
427        $extrametadata{$extrakeys_re} = $extrakeys_md;
428        $extrametafile{$extrakeys_re} = $extrakeys_mf;
429    }
430    delete($self->{'subdir_extrametakeys'}->{$local_dirname});
431    }
432   
433    # apply metadata pass for each of the files in the directory
434    my $num_files = scalar(@dir);
435    for (my $i = 0; $i < scalar(@dir); $i++) {
436    my $subfile = $dir[$i];
437    my $this_file_base_dir = $base_dir;
438    last if ($maxdocs != -1 && $count >= $maxdocs);
439    next if ($subfile =~ m/^\.\.?$/);
440    my $file_subfile = &util::filename_cat($file, $subfile);
441    my $full_filename = &util::filename_cat($this_file_base_dir, $file_subfile);
442    if ($self->file_is_blocked($block_hash,$full_filename)) {
443        print STDERR "DirectoryPlugin: file $full_filename was blocked for metadata_read\n" if ($verbosity > 2);
444        next;
445    }
446   
447    # Recursively read each $subfile
448    print $outhandle "DirectoryPlugin metadata recurring: $subfile\n" if ($verbosity > 2);
449   
450    $count += &plugin::metadata_read ($pluginfo, $this_file_base_dir,
451                      $file_subfile,$block_hash,
452                      \@extrametakeys, \%extrametadata,
453                      \%extrametafile,
454                      $processor, $maxdocs, $gli);
455    $additionalmetadata = 1;
456    }
457
458    # filter out any extrametakeys that mention subdirectories and store
459    # for later use (i.e. when that sub-directory is being processed)
460
461    foreach my $ek (@extrametakeys) {
462    my ($subdir_re,$extrakey_dir) = &File::Basename::fileparse($ek);
463   
464    $extrakey_dir =~ s/\\\./\./g; # remove RE syntax for .
465    $extrakey_dir =~ s/\\\\/\\/g; # remove RE syntax for \
466
467    my $dirsep_re = &util::get_re_dirsep();
468
469    my $ek_non_re = $ek;
470    $ek_non_re =~ s/\\\./\./g; # remove RE syntax for .
471    $ek_non_re =~ s/\\\\/\\/g; # remove RE syntax for \
472    if ($ek_non_re =~ m/$dirsep_re/) { # specifies at least one directory
473        my $md = $extrametadata{$ek};
474        my $mf = $extrametafile{$ek};
475
476        my $subdir_extrametakeys = $self->{'subdir_extrametakeys'};
477
478        my $subdir_rec = { 're' => $subdir_re, 'md' => $md, 'mf' => $mf };
479
480        # when its looked up, it must be relative to the base dir
481        push(@{$subdir_extrametakeys->{"$local_dirname$extrakey_dir"}},$subdir_rec);
482        #push(@{$subdir_extrametakeys->{"$extrakey_dir"}},$subdir_rec);
483    }
484    }
485   
486    # import each of the files in the directory
487    $count=0;
488    for (my $i = 0; $i <= scalar(@dir); $i++) {
489    # When every file in the directory has been done, pause for a moment (figuratively!)
490    # If the -recheck_directories argument hasn't been provided, stop now (default)
491    # Otherwise, re-read the contents of the directory to check for new files
492    #   Any new files are added to the @dir list and are processed as normal
493    #   This is necessary when documents to be indexed are specified in bibliographic DBs
494    #   These files are copied/downloaded and stored in a new folder at import time
495    if ($i == $num_files) {
496        last unless $self->{'recheck_directories'};
497
498        # Re-read the files in the directory to see if there are any new files
499        last if (!opendir (DIR, $dirname));
500        my @dirnow = readdir (DIR);
501        closedir (DIR);
502
503        # We're only interested if there are more files than there were before
504        last if (scalar(@dirnow) <= scalar(@dir));
505
506        # Any new files are added to the end of @dir to get processed by the loop
507        my $j;
508        foreach my $subfilenow (@dirnow) {
509        for ($j = 0; $j < $num_files; $j++) {
510            last if ($subfilenow eq $dir[$j]);
511        }
512        if ($j == $num_files) {
513            # New file
514            push(@dir, $subfilenow);
515        }
516        }
517        # When the new files have been processed, check again
518        $num_files = scalar(@dir);
519    }
520
521    my $subfile = $dir[$i];
522    my $this_file_base_dir = $base_dir;
523    last if ($maxdocs != -1 && ($count + $total_count) >= $maxdocs);
524    next if ($subfile =~ /^\.\.?$/);
525
526    my $file_subfile = &util::filename_cat($file, $subfile);
527    my $full_filename
528        = &util::filename_cat($this_file_base_dir,$file_subfile);
529
530    if ($self->file_is_blocked($block_hash,$full_filename)) {
531        print STDERR "DirectoryPlugin: file $full_filename was blocked for read\n" if ($verbosity > 2);
532        next;
533    }
534    #print STDERR "processing $full_filename\n";
535    # Follow Windows shortcuts
536    if ($subfile =~ /(?i)\.lnk$/ && $ENV{'GSDLOS'} =~ /^windows$/i) {
537        require Win32::Shortcut;
538        my $shortcut = new Win32::Shortcut(&util::filename_cat($dirname, $subfile));
539        if ($shortcut) {
540        # The file to be processed is now the target of the shortcut
541        $this_file_base_dir = "";
542        $file = "";
543        $subfile = $shortcut->Path;
544        }
545    }
546
547    # check for a symlink pointing back to a leading directory
548    if (-d "$dirname/$subfile" && -l "$dirname/$subfile") {
549        # readlink gives a "fatal error" on systems that don't implement
550        # symlinks. This assumes the the -l test above would fail on those.
551        my $linkdest=readlink "$dirname/$subfile";
552        if (!defined ($linkdest)) {
553        # system error - file not found?
554        warn "DirectoryPlugin: symlink problem - $!";
555        } else {
556        # see if link points to current or a parent directory
557        if ($linkdest =~ m@^[\./\\]+$@ ||
558            index($dirname, $linkdest) != -1) {
559            warn "DirectoryPlugin: Ignoring recursive symlink ($dirname/$subfile -> $linkdest)\n";
560            next;
561            ;
562        }
563        }
564    }
565
566    print $outhandle "DirectoryPlugin: preparing metadata for $subfile\n" if ($verbosity > 2);
567
568    # Make a copy of $in_metadata to pass to $subfile
569    my $out_metadata = {};
570    &metadatautil::combine_metadata_structures($out_metadata, $in_metadata);
571
572    # check the assocfile_info
573    if (defined $self->{'assocfile_info'}->{$full_filename}) {
574        &metadatautil::combine_metadata_structures($out_metadata, $self->{'assocfile_info'}->{$full_filename});
575    }
576        ## encode the filename as perl5 doesn't handle unicode filenames   
577       
578        my $tmpfile = Encode::encode_utf8($subfile);
579    # Next add metadata read in XML files (if it is supplied)
580    if ($additionalmetadata == 1) {
581        foreach my $filespec (@extrametakeys) {
582       
583        ## use the utf8 encoded filename to do the filename comparison
584        if ($tmpfile =~ /^$filespec$/) {
585            print $outhandle "File \"$subfile\" matches filespec \"$filespec\"\n"
586            if ($verbosity > 2);
587            my $mdref = $extrametadata{$filespec};
588            my $mfref = $extrametafile{$filespec};
589
590            # Add the list files where the metadata came from
591            # into the metadata table so we can track this
592            # This mechanism is similar to how gsdlassocfile works
593
594            my @metafile_pair = ();
595            foreach my $l (keys %$mfref) {
596            my $f = $mfref->{$l};
597            push (@metafile_pair, "$f : $l");
598            }
599
600            $mdref->{'gsdlmetafile'} = \@metafile_pair;
601
602            &metadatautil::combine_metadata_structures($out_metadata, $mdref);
603        }
604        }
605    }
606
607    if (defined $self->{'inf_timestamp'}) {
608        # Look to see if it's a completely new file
609
610        if (!$block_hash->{'new_files'}->{$full_filename}) {
611        # Not a new file, must be an existing file
612        # Let' see if it's newer than the last import.pl
613
614
615        if (! -d $full_filename) {
616            if (!$block_hash->{'reindex_files'}->{$full_filename}) {
617            # filename has been around for longer than inf_timestamp
618            print $outhandle "**** Skipping $subfile\n" if ($verbosity >3);
619            next;
620            }
621            else {
622            # Remove old folder in archives (might hash to something different)
623            # *** should be doing this on a Del one as well
624            # but leave folder name?? and ensure hashs to
625            # same again??
626
627            # Then let through as new doc??
628
629            # mark to doc-oids that rely on it for re-indexing
630            ## &GDBMUtils::gdbmDatabase();
631            }
632        }
633        }
634    }
635
636    # Recursively read each $subfile
637    print $outhandle "DirectoryPlugin recurring: $subfile\n" if ($verbosity > 2);
638   
639    $count += &plugin::read ($pluginfo, $this_file_base_dir,
640                 $file_subfile, $block_hash,
641                 $out_metadata, $processor, $maxdocs, ($total_count + $count), $gli);
642    }
643
644    return $count;
645}
646
647sub compile_stats {
648    my $self = shift(@_);
649    my ($stats) = @_;
650}
651
6521;
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