/[webpac2]/trunk/lib/WebPAC/Input.pm
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Revision 1306 - (show annotations)
Mon Sep 21 15:48:52 2009 UTC (14 years, 7 months ago) by dpavlin
File size: 17621 byte(s)
extract size from ll_db if supported
1 package WebPAC::Input;
2
3 use warnings;
4 use strict;
5
6 use lib 'lib';
7
8 use WebPAC::Common;
9 use base qw/WebPAC::Common/;
10 use Data::Dump qw/dump/;
11 use Encode qw/decode from_to/;
12 use YAML;
13
14 =head1 NAME
15
16 WebPAC::Input - read different file formats into WebPAC
17
18 =cut
19
20 our $VERSION = '0.19';
21
22 =head1 SYNOPSIS
23
24 This module implements input as database which have fixed and known
25 I<size> while indexing and single unique numeric identifier for database
26 position ranging from 1 to I<size>.
27
28 Simply, something that is indexed by unmber from 1 .. I<size>.
29
30 Examples of such databases are CDS/ISIS files, MARC files, lines in
31 text file, and so on.
32
33 Specific file formats are implemented using low-level interface modules,
34 located in C<WebPAC::Input::*> namespace which export C<open_db>,
35 C<fetch_rec> and optional C<init> functions.
36
37 Perhaps a little code snippet.
38
39 use WebPAC::Input;
40
41 my $db = WebPAC::Input->new(
42 module => 'WebPAC::Input::ISIS',
43 );
44
45 $db->open( path => '/path/to/database' );
46 print "database size: ",$db->size,"\n";
47 while (my $rec = $db->fetch) {
48 # do something with $rec
49 }
50
51
52
53 =head1 FUNCTIONS
54
55 =head2 new
56
57 Create new input database object.
58
59 my $db = new WebPAC::Input(
60 module => 'WebPAC::Input::MARC',
61 recode => 'char pairs',
62 no_progress_bar => 1,
63 input_config => {
64 mapping => [ 'foo', 'bar', 'baz' ],
65 },
66 );
67
68 C<module> is low-level file format module. See L<WebPAC::Input::ISIS> and
69 L<WebPAC::Input::MARC>.
70
71 C<recode> is optional string constisting of character or words pairs that
72 should be replaced in input stream.
73
74 C<no_progress_bar> disables progress bar output on C<STDOUT>
75
76 This function will also call low-level C<init> if it exists with same
77 parametars.
78
79 =cut
80
81 sub new {
82 my $class = shift;
83 my $self = {@_};
84 bless($self, $class);
85
86 my $log = $self->_get_logger;
87
88 $log->logconfess("code_page argument is not suppored any more.") if $self->{code_page};
89 $log->logconfess("encoding argument is not suppored any more.") if $self->{encoding};
90 $log->logconfess("lookup argument is not suppored any more. rewrite call to lookup_ref") if $self->{lookup};
91 $log->logconfess("low_mem argument is not suppored any more. rewrite it to load_row and save_row") if $self->{low_mem};
92
93 $log->logconfess("specify low-level file format module") unless ($self->{module});
94 my $module_path = $self->{module};
95 $module_path =~ s#::#/#g;
96 $module_path .= '.pm';
97 $log->debug("require low-level module $self->{module} from $module_path");
98
99 require $module_path;
100
101 $self ? return $self : return undef;
102 }
103
104 =head2 open
105
106 This function will read whole database in memory and produce lookups.
107
108 my $store; # simple in-memory hash
109
110 $input->open(
111 path => '/path/to/database/file',
112 input_encoding => 'cp852',
113 strict_encoding => 0,
114 limit => 500,
115 offset => 6000,
116 stats => 1,
117 lookup_coderef => sub {
118 my $rec = shift;
119 # store lookups
120 },
121 modify_records => {
122 900 => { '^a' => { ' : ' => '^b' } },
123 901 => { '*' => { '^b' => ' ; ' } },
124 },
125 modify_file => 'conf/modify/mapping.map',
126 save_row => sub {
127 my $a = shift;
128 $store->{ $a->{id} } = $a->{row};
129 },
130 load_row => sub {
131 my $a = shift;
132 return defined($store->{ $a->{id} }) &&
133 $store->{ $a->{id} };
134 },
135
136 );
137
138 By default, C<input_encoding> is assumed to be C<cp852>.
139
140 C<offset> is optional parametar to skip records at beginning.
141
142 C<limit> is optional parametar to read just C<limit> records from database
143
144 C<stats> create optional report about usage of fields and subfields
145
146 C<lookup_coderef> is closure to called to save data into lookups
147
148 C<modify_records> specify mapping from subfields to delimiters or from
149 delimiters to subfields, as well as oprations on fields (if subfield is
150 defined as C<*>.
151
152 C<modify_file> is alternative for C<modify_records> above which preserves order and offers
153 (hopefully) simplier sintax than YAML or perl (see L</modify_file_regex>). This option
154 overrides C<modify_records> if both exists for same input.
155
156 C<save_row> and C<load_row> are low-level implementation of store engine. Calling convention
157 is documented in example above.
158
159 C<strict_encoding> should really default to 1, but it doesn't for now.
160
161 Returns size of database, regardless of C<offset> and C<limit>
162 parametars, see also C<size>.
163
164 =cut
165
166 sub open {
167 my $self = shift;
168 my $arg = {@_};
169
170 my $log = $self->_get_logger();
171 $log->debug( "arguments: ",dump( $arg ));
172
173 $log->logconfess("encoding argument is not suppored any more.") if $self->{encoding};
174 $log->logconfess("code_page argument is not suppored any more.") if $self->{code_page};
175 $log->logconfess("lookup argument is not suppored any more. rewrite call to lookup_coderef") if ($arg->{lookup});
176 $log->logconfess("lookup_coderef must be CODE, not ",ref($arg->{lookup_coderef}))
177 if ($arg->{lookup_coderef} && ref($arg->{lookup_coderef}) ne 'CODE');
178
179 $log->debug( $arg->{lookup_coderef} ? '' : 'not ', "using lookup_coderef");
180
181 $log->logcroak("need path") if (! $arg->{'path'});
182 my $input_encoding = $arg->{'input_encoding'} || $self->{'input_encoding'} || 'cp852';
183
184 # store data in object
185 foreach my $v (qw/path offset limit/) {
186 $self->{$v} = $arg->{$v} if defined $arg->{$v};
187 }
188
189 if ($arg->{load_row} || $arg->{save_row}) {
190 $log->logconfess("save_row and load_row must be defined in pair and be CODE") unless (
191 ref($arg->{load_row}) eq 'CODE' &&
192 ref($arg->{save_row}) eq 'CODE'
193 );
194 $self->{load_row} = $arg->{load_row};
195 $self->{save_row} = $arg->{save_row};
196 $log->debug("using load_row and save_row instead of in-memory hash");
197 }
198
199 my $filter_ref;
200 my $recode_regex;
201 my $recode_map;
202
203 if ($self->{recode}) {
204 my @r = split(/\s/, $self->{recode});
205 if ($#r % 2 != 1) {
206 $log->logwarn("recode needs even number of elements (some number of valid pairs)");
207 } else {
208 while (@r) {
209 my $from = shift @r;
210 my $to = shift @r;
211 $recode_map->{$from} = $to;
212 }
213
214 $recode_regex = join '|' => keys %{ $recode_map };
215
216 $log->debug("using recode regex: $recode_regex");
217 }
218
219 }
220
221 my $rec_regex;
222 if (my $p = $arg->{modify_file}) {
223 $log->debug("using modify_file $p");
224 $rec_regex = $self->modify_file_regexps( $p );
225 } elsif (my $h = $arg->{modify_records}) {
226 $log->debug("using modify_records ", sub { dump( $h ) });
227 $rec_regex = $self->modify_record_regexps(%{ $h });
228 }
229 $log->debug("rec_regex: ", sub { dump($rec_regex) }) if ($rec_regex);
230
231 my $class = $self->{module} || $log->logconfess("can't get low-level module name!");
232
233 $arg->{$_} = $self->{$_} foreach qw(offset limit);
234
235 my $ll_db = $class->new(
236 path => $arg->{path},
237 input_config => $arg->{input_config} || $self->{input_config},
238 # filter => sub {
239 # my ($l,$f_nr) = @_;
240 # return unless defined($l);
241 # $l = decode($input_encoding, $l);
242 # $l =~ s/($recode_regex)/$recode_map->{$1}/g if ($recode_regex && $recode_map);
243 # return $l;
244 # },
245 %{ $arg },
246 );
247
248 # save for dump and input_module
249 $self->{ll_db} = $ll_db;
250
251 unless (defined($ll_db)) {
252 $log->logwarn("can't open database $arg->{path}, skipping...");
253 return;
254 }
255
256 my $size = $ll_db->size;
257
258 unless ($size) {
259 $log->logwarn("no records in database $arg->{path}, skipping...");
260 return;
261 }
262
263 my $from_rec = 1;
264 my $to_rec = $size;
265
266 if (my $s = $self->{offset}) {
267 $log->debug("offset $s records");
268 $from_rec = $s + 1;
269 } else {
270 $self->{offset} = $from_rec - 1;
271 }
272
273 if ($self->{limit}) {
274 $log->debug("limiting to ",$self->{limit}," records");
275 $to_rec = $from_rec + $self->{limit} - 1;
276 $to_rec = $size if ($to_rec > $size);
277 }
278
279 # store size for later
280 $self->{size} = $to_rec - $from_rec + 1;
281
282 my $strict_encoding = $arg->{strict_encoding} || $self->{strict_encoding}; ## FIXME should be 1 really
283
284 $log->info("processing $self->{size}/$size records [$from_rec-$to_rec]",
285 " encoding $input_encoding ", $strict_encoding ? ' [strict]' : '',
286 $self->{stats} ? ' [stats]' : '',
287 );
288
289 # read database
290 for (my $pos = $from_rec; $pos <= $to_rec; $pos++) {
291
292 $log->debug("position: $pos\n");
293
294 my $rec = $ll_db->fetch_rec($pos, sub {
295 my ($l,$f_nr,$debug) = @_;
296 # return unless defined($l);
297 # return $l unless ($rec_regex && $f_nr);
298
299 return unless ( defined($l) && defined($f_nr) );
300
301 warn "-=> $f_nr ## |$l|\n" if ($debug);
302 $log->debug("-=> $f_nr ## $l");
303
304 # codepage conversion and recode_regex
305 $l = decode($input_encoding, $l, 1);
306 $l =~ s/($recode_regex)/$recode_map->{$1}/g if ($recode_regex && $recode_map);
307
308 # apply regexps
309 if ($rec_regex && defined($rec_regex->{$f_nr})) {
310 $log->logconfess("regexps->{$f_nr} must be ARRAY") if (ref($rec_regex->{$f_nr}) ne 'ARRAY');
311 my $c = 0;
312 foreach my $r (@{ $rec_regex->{$f_nr} }) {
313 my $old_l = $l;
314 $log->logconfess("expected regex in ", dump( $r )) unless defined($r->{regex});
315 eval '$l =~ ' . $r->{regex};
316 if ($old_l ne $l) {
317 my $d = "|$old_l| -> |$l| "; # . $r->{regex};
318 $d .= ' +' . $r->{line} . ' ' . $r->{file} if defined($r->{line});
319 $d .= ' ' . $r->{debug} if defined($r->{debug});
320 $log->debug("MODIFY $d");
321 warn "*** $d\n" if ($debug);
322
323 }
324 $log->error("error applying regex: ",dump($r), $@) if $@;
325 }
326 }
327
328 $log->debug("<=- $f_nr ## |$l|");
329 warn "<=- $f_nr ## $l\n" if ($debug);
330 return $l;
331 });
332
333 $log->debug(sub { dump($rec) });
334
335 if (! $rec) {
336 $log->warn("record $pos empty? skipping...");
337 next;
338 }
339
340 # store
341 if ($self->{save_row}) {
342 $self->{save_row}->({
343 id => $pos,
344 row => $rec,
345 });
346 } else {
347 $self->{data}->{$pos} = $rec;
348 }
349
350 # create lookup
351 $arg->{'lookup_coderef'}->( $rec ) if ($rec && $arg->{'lookup_coderef'});
352
353 # update counters for statistics
354 if ($self->{stats}) {
355
356 # fetch clean record with regexpes applied for statistics
357 my $rec = $ll_db->fetch_rec($pos);
358
359 foreach my $fld (keys %{ $rec }) {
360 $self->{_stats}->{fld}->{ $fld }++;
361
362 #$log->logdie("invalid record fild $fld, not ARRAY")
363 next unless (ref($rec->{ $fld }) eq 'ARRAY');
364
365 foreach my $row (@{ $rec->{$fld} }) {
366
367 if (ref($row) eq 'HASH') {
368
369 foreach my $sf (keys %{ $row }) {
370 next if ($sf eq 'subfields');
371 $self->{_stats}->{sf}->{ $fld }->{ $sf }->{count}++;
372 $self->{_stats}->{sf}->{ $fld }->{ $sf }->{repeatable}++
373 if (ref($row->{$sf}) eq 'ARRAY');
374 }
375
376 } else {
377 $self->{_stats}->{repeatable}->{ $fld }++;
378 }
379 }
380 }
381 }
382
383 $self->progress_bar($pos,$to_rec) unless ($self->{no_progress_bar});
384
385 }
386
387 $self->{pos} = -1;
388 $self->{last_pcnt} = 0;
389
390 # store max mfn and return it.
391 $self->{max_pos} = $to_rec;
392 $log->debug("max_pos: $to_rec");
393
394 return $size;
395 }
396
397 sub input_module { $_[0]->{ll_db} }
398
399 =head2 fetch
400
401 Fetch next record from database. It will also displays progress bar.
402
403 my $rec = $isis->fetch;
404
405 Record from this function should probably go to C<data_structure> for
406 normalisation.
407
408 =cut
409
410 sub fetch {
411 my $self = shift;
412
413 my $log = $self->_get_logger();
414
415 $log->logconfess("it seems that you didn't load database!") unless ($self->{pos});
416
417 if ($self->{pos} == -1) {
418 $self->{pos} = $self->{offset} + 1;
419 } else {
420 $self->{pos}++;
421 }
422
423 my $mfn = $self->{pos};
424
425 if ($mfn > $self->{max_pos}) {
426 $self->{pos} = $self->{max_pos};
427 $log->debug("at EOF");
428 return;
429 }
430
431 $self->progress_bar($mfn,$self->{max_pos}) unless ($self->{no_progress_bar});
432
433 my $rec;
434
435 if ($self->{load_row}) {
436 $rec = $self->{load_row}->({ id => $mfn });
437 } else {
438 $rec = $self->{data}->{$mfn};
439 }
440
441 $rec ||= 0E0;
442 }
443
444 =head2 pos
445
446 Returns current record number (MFN).
447
448 print $isis->pos;
449
450 First record in database has position 1.
451
452 =cut
453
454 sub pos {
455 my $self = shift;
456 return $self->{pos};
457 }
458
459
460 =head2 size
461
462 Returns number of records in database
463
464 print $isis->size;
465
466 Result from this function can be used to loop through all records
467
468 foreach my $mfn ( 1 ... $isis->size ) { ... }
469
470 because it takes into account C<offset> and C<limit>.
471
472 =cut
473
474 sub size {
475 my $self = shift;
476 $self->{ll_db}->size if $self->{ll_db}->can('size');
477 return $self->{size}; # FIXME this is buggy if open is called multiple times!
478 }
479
480 =head2 seek
481
482 Seek to specified MFN in file.
483
484 $isis->seek(42);
485
486 First record in database has position 1.
487
488 =cut
489
490 sub seek {
491 my $self = shift;
492 my $pos = shift;
493
494 my $log = $self->_get_logger();
495
496 $log->logconfess("called without pos") unless defined($pos);
497
498 if ($pos < 1) {
499 $log->warn("seek before first record");
500 $pos = 1;
501 } elsif ($pos > $self->{max_pos}) {
502 $log->warn("seek beyond last record");
503 $pos = $self->{max_pos};
504 }
505
506 return $self->{pos} = (($pos - 1) || -1);
507 }
508
509 =head2 stats
510
511 Dump statistics about field and subfield usage
512
513 print $input->stats;
514
515 =cut
516
517 sub stats {
518 my $self = shift;
519
520 my $log = $self->_get_logger();
521
522 my $s = $self->{_stats};
523 if (! $s) {
524 $log->warn("called stats, but there is no statistics collected");
525 return;
526 }
527
528 my $max_fld = 0;
529
530 my $out = join("\n",
531 map {
532 my $f = $_;
533 die "no field in ", dump( $s->{fld} ) unless defined( $f );
534 my $v = $s->{fld}->{$f} || die "no s->{fld}->{$f}";
535 $max_fld = $v if ($v > $max_fld);
536
537 my $o = sprintf("%4s %d ~", $f, $v);
538
539 if (defined($s->{sf}->{$f})) {
540 my @subfields = keys %{ $s->{sf}->{$f} };
541 map {
542 $o .= sprintf(" %s:%d%s", $_,
543 $s->{sf}->{$f}->{$_}->{count},
544 $s->{sf}->{$f}->{$_}->{repeatable} ? '*' : '',
545 );
546 } (
547 # first indicators and other special subfields
548 sort( grep { length($_) > 1 } @subfields ),
549 # then subfileds (single char)
550 sort( grep { length($_) == 1 } @subfields ),
551 );
552 }
553
554 if (my $v_r = $s->{repeatable}->{$f}) {
555 $o .= " ($v_r)" if ($v_r != $v);
556 }
557
558 $o;
559 } sort {
560 if ( $a =~ m/^\d+$/ && $b =~ m/^\d+$/ ) {
561 $a <=> $b
562 } else {
563 $a cmp $b
564 }
565 } keys %{ $s->{fld} }
566 );
567
568 $log->debug( sub { dump($s) } );
569
570 my $path = 'var/stats.yml';
571 YAML::DumpFile( $path, $s );
572 $log->info( 'created ', $path, ' with ', -s $path, ' bytes' );
573
574 return $out;
575 }
576
577 =head2 dump_ascii
578
579 Display humanly readable dump of record
580
581 =cut
582
583 sub dump_ascii {
584 my $self = shift;
585
586 return unless $self->{ll_db};
587
588 if ($self->{ll_db}->can('dump_ascii')) {
589 return $self->{ll_db}->dump_ascii( $self->{pos} );
590 } else {
591 return dump( $self->{ll_db}->fetch_rec( $self->{pos} ) );
592 }
593 }
594
595 =head2 _get_regex
596
597 Helper function called which create regexps to be execute on code.
598
599 _get_regex( 900, 'regex:[0-9]+' ,'numbers' );
600 _get_regex( 900, '^b', ' : ^b' );
601
602 It supports perl regexps with C<regex:> prefix to from value and has
603 additional logic to skip empty subfields.
604
605 =cut
606
607 sub _get_regex {
608 my ($sf,$from,$to) = @_;
609
610 # protect /
611 $from =~ s!/!\\/!gs;
612 $to =~ s!/!\\/!gs;
613
614 if ($from =~ m/^regex:(.+)$/) {
615 $from = $1;
616 } else {
617 $from = '\Q' . $from . '\E';
618 }
619 if ($sf =~ /^\^/) {
620 my $need_subfield_data = '*'; # no
621 # if from is also subfield, require some data in between
622 # to correctly skip empty subfields
623 $need_subfield_data = '+' if ($from =~ m/^\\Q\^/);
624 return
625 's/\Q'. $sf .'\E([^\^]' . $need_subfield_data . '?)'. $from .'([^\^]*?)/'. $sf .'$1'. $to .'$2/';
626 } else {
627 return
628 's/'. $from .'/'. $to .'/g';
629 }
630 }
631
632
633 =head2 modify_record_regexps
634
635 Generate hash with regexpes to be applied using L<filter>.
636
637 my $regexpes = $input->modify_record_regexps(
638 900 => { '^a' => { ' : ' => '^b' } },
639 901 => { '*' => { '^b' => ' ; ' } },
640 );
641
642 =cut
643
644 sub modify_record_regexps {
645 my $self = shift;
646 my $modify_record = {@_};
647
648 my $regexpes;
649
650 my $log = $self->_get_logger();
651
652 foreach my $f (keys %$modify_record) {
653 $log->debug("field: $f");
654
655 foreach my $sf (keys %{ $modify_record->{$f} }) {
656 $log->debug("subfield: $sf");
657
658 foreach my $from (keys %{ $modify_record->{$f}->{$sf} }) {
659 my $to = $modify_record->{$f}->{$sf}->{$from};
660 #die "no field?" unless defined($to);
661 my $d = "|$from| -> |$to|";
662 $log->debug("transform: $d");
663
664 my $regex = _get_regex($sf,$from,$to);
665 push @{ $regexpes->{$f} }, { regex => $regex, debug => $d };
666 $log->debug("regex: $regex");
667 }
668 }
669 }
670
671 return $regexpes;
672 }
673
674 =head2 modify_file_regexps
675
676 Generate hash with regexpes to be applied using L<filter> from
677 pseudo hash/yaml format for regex mappings.
678
679 It should be obvious:
680
681 200
682 '^a'
683 ' : ' => '^e'
684 ' = ' => '^d'
685
686 In field I<200> find C<'^a'> and then C<' : '>, and replace it with C<'^e'>.
687 In field I<200> find C<'^a'> and then C<' = '>, and replace it with C<'^d'>.
688
689 my $regexpes = $input->modify_file_regexps( 'conf/modify/common.pl' );
690
691 On undef path it will just return.
692
693 =cut
694
695 sub modify_file_regexps {
696 my $self = shift;
697
698 my $modify_path = shift || return;
699
700 my $log = $self->_get_logger();
701
702 my $regexpes;
703
704 CORE::open(my $fh, $modify_path) || $log->logdie("can't open modify file $modify_path: $!");
705
706 my ($f,$sf);
707
708 while(<$fh>) {
709 chomp;
710 next if (/^#/ || /^\s*$/);
711
712 if (/^\s*(\d+)\s*$/) {
713 $f = $1;
714 $log->debug("field: $f");
715 next;
716 } elsif (/^\s*'([^']*)'\s*$/) {
717 $sf = $1;
718 $log->die("can't define subfiled before field in: $_") unless ($f);
719 $log->debug("subfield: $sf");
720 } elsif (/^\s*'([^']*)'\s*=>\s*'([^']*)'\s*$/) {
721 my ($from,$to) = ($1, $2);
722
723 $log->debug("transform: |$from| -> |$to|");
724
725 my $regex = _get_regex($sf,$from,$to);
726 push @{ $regexpes->{$f} }, {
727 regex => $regex,
728 file => $modify_path,
729 line => $.,
730 };
731 $log->debug("regex: $regex");
732 } else {
733 die "can't parse: $_";
734 }
735 }
736
737 return $regexpes;
738 }
739
740 =head1 AUTHOR
741
742 Dobrica Pavlinusic, C<< <dpavlin@rot13.org> >>
743
744 =head1 COPYRIGHT & LICENSE
745
746 Copyright 2005-2006 Dobrica Pavlinusic, All Rights Reserved.
747
748 This program is free software; you can redistribute it and/or modify it
749 under the same terms as Perl itself.
750
751 =cut
752
753 1; # End of WebPAC::Input

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