/[webpac2]/trunk/lib/WebPAC/Input.pm
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Revision 909 - (show annotations)
Tue Oct 30 01:46:41 2007 UTC (16 years, 6 months ago) by dpavlin
File size: 16930 byte(s)
 r1362@llin:  dpavlin | 2007-10-30 02:46:05 +0100
 Show indicators (available when using WebPAC::Input::MARC) as
 first two subfileds in statistics insted in alphabetical order

1 package WebPAC::Input;
2
3 use warnings;
4 use strict;
5
6 use blib;
7
8 use WebPAC::Common;
9 use base qw/WebPAC::Common/;
10 use Data::Dump qw/dump/;
11 use Encode qw/from_to/;
12
13 =head1 NAME
14
15 WebPAC::Input - read different file formats into WebPAC
16
17 =head1 VERSION
18
19 Version 0.18
20
21 =cut
22
23 our $VERSION = '0.18';
24
25 =head1 SYNOPSIS
26
27 This module implements input as database which have fixed and known
28 I<size> while indexing and single unique numeric identifier for database
29 position ranging from 1 to I<size>.
30
31 Simply, something that is indexed by unmber from 1 .. I<size>.
32
33 Examples of such databases are CDS/ISIS files, MARC files, lines in
34 text file, and so on.
35
36 Specific file formats are implemented using low-level interface modules,
37 located in C<WebPAC::Input::*> namespace which export C<open_db>,
38 C<fetch_rec> and optional C<init> functions.
39
40 Perhaps a little code snippet.
41
42 use WebPAC::Input;
43
44 my $db = WebPAC::Input->new(
45 module => 'WebPAC::Input::ISIS',
46 );
47
48 $db->open( path => '/path/to/database' );
49 print "database size: ",$db->size,"\n";
50 while (my $rec = $db->fetch) {
51 # do something with $rec
52 }
53
54
55
56 =head1 FUNCTIONS
57
58 =head2 new
59
60 Create new input database object.
61
62 my $db = new WebPAC::Input(
63 module => 'WebPAC::Input::MARC',
64 encoding => 'ISO-8859-2',
65 recode => 'char pairs',
66 no_progress_bar => 1,
67 input_config => {
68 mapping => [ 'foo', 'bar', 'baz' ],
69 },
70 );
71
72 C<module> is low-level file format module. See L<WebPAC::Input::ISIS> and
73 L<WebPAC::Input::MARC>.
74
75 Optional parametar C<encoding> specify application code page (which will be
76 used internally). This should probably be your terminal encoding, and by
77 default, it C<ISO-8859-2>.
78
79 C<recode> is optional string constisting of character or words pairs that
80 should be replaced in input stream.
81
82 C<no_progress_bar> disables progress bar output on C<STDOUT>
83
84 This function will also call low-level C<init> if it exists with same
85 parametars.
86
87 =cut
88
89 sub new {
90 my $class = shift;
91 my $self = {@_};
92 bless($self, $class);
93
94 my $log = $self->_get_logger;
95
96 $log->logconfess("code_page argument is not suppored any more. change it to encoding") if ($self->{lookup});
97 $log->logconfess("lookup argument is not suppored any more. rewrite call to lookup_ref") if ($self->{lookup});
98 $log->logconfess("low_mem argument is not suppored any more. rewrite it to load_row and save_row") if ($self->{low_mem});
99
100 $log->logconfess("specify low-level file format module") unless ($self->{module});
101 my $module_path = $self->{module};
102 $module_path =~ s#::#/#g;
103 $module_path .= '.pm';
104 $log->debug("require low-level module $self->{module} from $module_path");
105
106 require $module_path;
107
108 $self->{'encoding'} ||= 'ISO-8859-2';
109
110 $self ? return $self : return undef;
111 }
112
113 =head2 open
114
115 This function will read whole database in memory and produce lookups.
116
117 my $store; # simple in-memory hash
118
119 $input->open(
120 path => '/path/to/database/file',
121 code_page => 'cp852',
122 limit => 500,
123 offset => 6000,
124 stats => 1,
125 lookup_coderef => sub {
126 my $rec = shift;
127 # store lookups
128 },
129 modify_records => {
130 900 => { '^a' => { ' : ' => '^b' } },
131 901 => { '*' => { '^b' => ' ; ' } },
132 },
133 modify_file => 'conf/modify/mapping.map',
134 save_row => sub {
135 my $a = shift;
136 $store->{ $a->{id} } = $a->{row};
137 },
138 load_row => sub {
139 my $a = shift;
140 return defined($store->{ $a->{id} }) &&
141 $store->{ $a->{id} };
142 },
143
144 );
145
146 By default, C<code_page> is assumed to be C<cp852>.
147
148 C<offset> is optional parametar to position at some offset before reading from database.
149
150 C<limit> is optional parametar to read just C<limit> records from database
151
152 C<stats> create optional report about usage of fields and subfields
153
154 C<lookup_coderef> is closure to called to save data into lookups
155
156 C<modify_records> specify mapping from subfields to delimiters or from
157 delimiters to subfields, as well as oprations on fields (if subfield is
158 defined as C<*>.
159
160 C<modify_file> is alternative for C<modify_records> above which preserves order and offers
161 (hopefully) simplier sintax than YAML or perl (see L</modify_file_regex>). This option
162 overrides C<modify_records> if both exists for same input.
163
164 C<save_row> and C<load_row> are low-level implementation of store engine. Calling convention
165 is documented in example above.
166
167 Returns size of database, regardless of C<offset> and C<limit>
168 parametars, see also C<size>.
169
170 =cut
171
172 sub open {
173 my $self = shift;
174 my $arg = {@_};
175
176 my $log = $self->_get_logger();
177
178 $log->logconfess("lookup argument is not suppored any more. rewrite call to lookup_coderef") if ($arg->{lookup});
179 $log->logconfess("lookup_coderef must be CODE, not ",ref($arg->{lookup_coderef}))
180 if ($arg->{lookup_coderef} && ref($arg->{lookup_coderef}) ne 'CODE');
181
182 $log->debug( $arg->{lookup_coderef} ? '' : 'not ', "using lookup_coderef");
183
184 $log->logcroak("need path") if (! $arg->{'path'});
185 my $code_page = $arg->{'code_page'} || 'cp852';
186
187 # store data in object
188 $self->{'input_code_page'} = $code_page;
189 foreach my $v (qw/path offset limit/) {
190 $self->{$v} = $arg->{$v} if ($arg->{$v});
191 }
192
193 if ($arg->{load_row} || $arg->{save_row}) {
194 $log->logconfess("save_row and load_row must be defined in pair and be CODE") unless (
195 ref($arg->{load_row}) eq 'CODE' &&
196 ref($arg->{save_row}) eq 'CODE'
197 );
198 $self->{load_row} = $arg->{load_row};
199 $self->{save_row} = $arg->{save_row};
200 $log->debug("using load_row and save_row instead of in-memory hash");
201 }
202
203 my $filter_ref;
204 my $recode_regex;
205 my $recode_map;
206
207 if ($self->{recode}) {
208 my @r = split(/\s/, $self->{recode});
209 if ($#r % 2 != 1) {
210 $log->logwarn("recode needs even number of elements (some number of valid pairs)");
211 } else {
212 while (@r) {
213 my $from = shift @r;
214 my $to = shift @r;
215 $recode_map->{$from} = $to;
216 }
217
218 $recode_regex = join '|' => keys %{ $recode_map };
219
220 $log->debug("using recode regex: $recode_regex");
221 }
222
223 }
224
225 my $rec_regex;
226 if (my $p = $arg->{modify_file}) {
227 $log->debug("using modify_file $p");
228 $rec_regex = $self->modify_file_regexps( $p );
229 } elsif (my $h = $arg->{modify_records}) {
230 $log->debug("using modify_records ", sub { dump( $h ) });
231 $rec_regex = $self->modify_record_regexps(%{ $h });
232 }
233 $log->debug("rec_regex: ", sub { dump($rec_regex) }) if ($rec_regex);
234
235 my $class = $self->{module} || $log->logconfess("can't get low-level module name!");
236
237 my $ll_db = $class->new(
238 path => $arg->{path},
239 input_config => $arg->{input_config} || $self->{input_config},
240 # filter => sub {
241 # my ($l,$f_nr) = @_;
242 # return unless defined($l);
243 # from_to($l, $code_page, $self->{'encoding'});
244 # $l =~ s/($recode_regex)/$recode_map->{$1}/g if ($recode_regex && $recode_map);
245 # return $l;
246 # },
247 %{ $arg },
248 );
249
250 unless (defined($ll_db)) {
251 $log->logwarn("can't open database $arg->{path}, skipping...");
252 return;
253 }
254
255 my $size = $ll_db->size;
256
257 unless ($size) {
258 $log->logwarn("no records in database $arg->{path}, skipping...");
259 return;
260 }
261
262 my $from_rec = 1;
263 my $to_rec = $size;
264
265 if (my $s = $self->{offset}) {
266 $log->debug("skipping to MFN $s");
267 $from_rec = $s;
268 } else {
269 $self->{offset} = $from_rec;
270 }
271
272 if ($self->{limit}) {
273 $log->debug("limiting to ",$self->{limit}," records");
274 $to_rec = $from_rec + $self->{limit} - 1;
275 $to_rec = $size if ($to_rec > $size);
276 }
277
278 # store size for later
279 $self->{size} = ($to_rec - $from_rec) ? ($to_rec - $from_rec + 1) : 0;
280
281 $log->info("processing $self->{size}/$size records [$from_rec-$to_rec] convert $code_page -> $self->{encoding}", $self->{stats} ? ' [stats]' : '');
282
283 # read database
284 for (my $pos = $from_rec; $pos <= $to_rec; $pos++) {
285
286 $log->debug("position: $pos\n");
287
288 my $rec = $ll_db->fetch_rec($pos, sub {
289 my ($l,$f_nr,$debug) = @_;
290 # return unless defined($l);
291 # return $l unless ($rec_regex && $f_nr);
292
293 return unless ( defined($l) && defined($f_nr) );
294
295 warn "-=> $f_nr ## |$l|\n" if ($debug);
296 $log->debug("-=> $f_nr ## $l");
297
298 # codepage conversion and recode_regex
299 from_to($l, $code_page, $self->{'encoding'});
300 $l =~ s/($recode_regex)/$recode_map->{$1}/g if ($recode_regex && $recode_map);
301
302 # apply regexps
303 if ($rec_regex && defined($rec_regex->{$f_nr})) {
304 $log->logconfess("regexps->{$f_nr} must be ARRAY") if (ref($rec_regex->{$f_nr}) ne 'ARRAY');
305 my $c = 0;
306 foreach my $r (@{ $rec_regex->{$f_nr} }) {
307 my $old_l = $l;
308 $log->logconfess("expected regex in ", dump( $r )) unless defined($r->{regex});
309 eval '$l =~ ' . $r->{regex};
310 if ($old_l ne $l) {
311 my $d = "|$old_l| -> |$l| "; # . $r->{regex};
312 $d .= ' +' . $r->{line} . ' ' . $r->{file} if defined($r->{line});
313 $d .= ' ' . $r->{debug} if defined($r->{debug});
314 $log->debug("MODIFY $d");
315 warn "*** $d\n" if ($debug);
316
317 }
318 $log->error("error applying regex: $r") if ($@);
319 }
320 }
321
322 $log->debug("<=- $f_nr ## |$l|");
323 warn "<=- $f_nr ## $l\n" if ($debug);
324 return $l;
325 });
326
327 $log->debug(sub { dump($rec) });
328
329 if (! $rec) {
330 $log->warn("record $pos empty? skipping...");
331 next;
332 }
333
334 # store
335 if ($self->{save_row}) {
336 $self->{save_row}->({
337 id => $pos,
338 row => $rec,
339 });
340 } else {
341 $self->{data}->{$pos} = $rec;
342 }
343
344 # create lookup
345 $arg->{'lookup_coderef'}->( $rec ) if ($rec && $arg->{'lookup_coderef'});
346
347 # update counters for statistics
348 if ($self->{stats}) {
349
350 # fetch clean record with regexpes applied for statistics
351 my $rec = $ll_db->fetch_rec($pos);
352
353 foreach my $fld (keys %{ $rec }) {
354 $self->{_stats}->{fld}->{ $fld }++;
355
356 $log->logdie("invalid record fild $fld, not ARRAY")
357 unless (ref($rec->{ $fld }) eq 'ARRAY');
358
359 foreach my $row (@{ $rec->{$fld} }) {
360
361 if (ref($row) eq 'HASH') {
362
363 foreach my $sf (keys %{ $row }) {
364 next if ($sf eq 'subfields');
365 $self->{_stats}->{sf}->{ $fld }->{ $sf }->{count}++;
366 $self->{_stats}->{sf}->{ $fld }->{ $sf }->{repeatable}++
367 if (ref($row->{$sf}) eq 'ARRAY');
368 }
369
370 } else {
371 $self->{_stats}->{repeatable}->{ $fld }++;
372 }
373 }
374 }
375 }
376
377 $self->progress_bar($pos,$to_rec) unless ($self->{no_progress_bar});
378
379 }
380
381 $self->{pos} = -1;
382 $self->{last_pcnt} = 0;
383
384 # store max mfn and return it.
385 $self->{max_pos} = $to_rec;
386 $log->debug("max_pos: $to_rec");
387
388 # save for dump
389 $self->{ll_db} = $ll_db;
390
391 return $size;
392 }
393
394 =head2 fetch
395
396 Fetch next record from database. It will also displays progress bar.
397
398 my $rec = $isis->fetch;
399
400 Record from this function should probably go to C<data_structure> for
401 normalisation.
402
403 =cut
404
405 sub fetch {
406 my $self = shift;
407
408 my $log = $self->_get_logger();
409
410 $log->logconfess("it seems that you didn't load database!") unless ($self->{pos});
411
412 if ($self->{pos} == -1) {
413 $self->{pos} = $self->{offset};
414 } else {
415 $self->{pos}++;
416 }
417
418 my $mfn = $self->{pos};
419
420 if ($mfn > $self->{max_pos}) {
421 $self->{pos} = $self->{max_pos};
422 $log->debug("at EOF");
423 return;
424 }
425
426 $self->progress_bar($mfn,$self->{max_pos}) unless ($self->{no_progress_bar});
427
428 my $rec;
429
430 if ($self->{load_row}) {
431 $rec = $self->{load_row}->({ id => $mfn });
432 } else {
433 $rec = $self->{data}->{$mfn};
434 }
435
436 $rec ||= 0E0;
437 }
438
439 =head2 pos
440
441 Returns current record number (MFN).
442
443 print $isis->pos;
444
445 First record in database has position 1.
446
447 =cut
448
449 sub pos {
450 my $self = shift;
451 return $self->{pos};
452 }
453
454
455 =head2 size
456
457 Returns number of records in database
458
459 print $isis->size;
460
461 Result from this function can be used to loop through all records
462
463 foreach my $mfn ( 1 ... $isis->size ) { ... }
464
465 because it takes into account C<offset> and C<limit>.
466
467 =cut
468
469 sub size {
470 my $self = shift;
471 return $self->{size};
472 }
473
474 =head2 seek
475
476 Seek to specified MFN in file.
477
478 $isis->seek(42);
479
480 First record in database has position 1.
481
482 =cut
483
484 sub seek {
485 my $self = shift;
486 my $pos = shift;
487
488 my $log = $self->_get_logger();
489
490 $log->logconfess("called without pos") unless defined($pos);
491
492 if ($pos < 1) {
493 $log->warn("seek before first record");
494 $pos = 1;
495 } elsif ($pos > $self->{max_pos}) {
496 $log->warn("seek beyond last record");
497 $pos = $self->{max_pos};
498 }
499
500 return $self->{pos} = (($pos - 1) || -1);
501 }
502
503 =head2 stats
504
505 Dump statistics about field and subfield usage
506
507 print $input->stats;
508
509 =cut
510
511 sub stats {
512 my $self = shift;
513
514 my $log = $self->_get_logger();
515
516 my $s = $self->{_stats};
517 if (! $s) {
518 $log->warn("called stats, but there is no statistics collected");
519 return;
520 }
521
522 my $max_fld = 0;
523
524 my $out = join("\n",
525 map {
526 my $f = $_;
527 die "no field in ", dump( $s->{fld} ) unless defined( $f );
528 my $v = $s->{fld}->{$f} || die "no s->{fld}->{$f}";
529 $max_fld = $v if ($v > $max_fld);
530
531 my $o = sprintf("%4s %d ~", $f, $v);
532
533 if (defined($s->{sf}->{$f})) {
534 my @subfields = keys %{ $s->{sf}->{$f} };
535 warn "$f has subfields ",dump( @subfields );
536 map {
537 $o .= sprintf(" %s:%d%s", $_,
538 $s->{sf}->{$f}->{$_}->{count},
539 $s->{sf}->{$f}->{$_}->{repeatable} ? '*' : '',
540 );
541 } (
542 # first indicators
543 sort( grep( /^i[12]$/, @subfields ) ),
544 # then subfileds
545 sort( grep( !/^i[12]$/, @subfields ) ),
546 );
547 }
548
549 if (my $v_r = $s->{repeatable}->{$f}) {
550 $o .= " ($v_r)" if ($v_r != $v);
551 }
552
553 $o;
554 } sort { $a <=> $b } keys %{ $s->{fld} }
555 );
556
557 $log->debug( sub { dump($s) } );
558
559 return $out;
560 }
561
562 =head2 dump_ascii
563
564 Display humanly readable dump of record
565
566 =cut
567
568 sub dump_ascii {
569 my $self = shift;
570
571 return unless $self->{ll_db};
572
573 if ($self->{ll_db}->can('dump_ascii')) {
574 return $self->{ll_db}->dump_ascii( $self->{pos} );
575 } else {
576 return dump( $self->{ll_db}->fetch_rec( $self->{pos} ) );
577 }
578 }
579
580 =head2 _get_regex
581
582 Helper function called which create regexps to be execute on code.
583
584 _get_regex( 900, 'regex:[0-9]+' ,'numbers' );
585 _get_regex( 900, '^b', ' : ^b' );
586
587 It supports perl regexps with C<regex:> prefix to from value and has
588 additional logic to skip empty subfields.
589
590 =cut
591
592 sub _get_regex {
593 my ($sf,$from,$to) = @_;
594
595 # protect /
596 $from =~ s!/!\\/!gs;
597 $to =~ s!/!\\/!gs;
598
599 if ($from =~ m/^regex:(.+)$/) {
600 $from = $1;
601 } else {
602 $from = '\Q' . $from . '\E';
603 }
604 if ($sf =~ /^\^/) {
605 my $need_subfield_data = '*'; # no
606 # if from is also subfield, require some data in between
607 # to correctly skip empty subfields
608 $need_subfield_data = '+' if ($from =~ m/^\\Q\^/);
609 return
610 's/\Q'. $sf .'\E([^\^]' . $need_subfield_data . '?)'. $from .'([^\^]*?)/'. $sf .'$1'. $to .'$2/';
611 } else {
612 return
613 's/'. $from .'/'. $to .'/g';
614 }
615 }
616
617
618 =head2 modify_record_regexps
619
620 Generate hash with regexpes to be applied using L<filter>.
621
622 my $regexpes = $input->modify_record_regexps(
623 900 => { '^a' => { ' : ' => '^b' } },
624 901 => { '*' => { '^b' => ' ; ' } },
625 );
626
627 =cut
628
629 sub modify_record_regexps {
630 my $self = shift;
631 my $modify_record = {@_};
632
633 my $regexpes;
634
635 my $log = $self->_get_logger();
636
637 foreach my $f (keys %$modify_record) {
638 $log->debug("field: $f");
639
640 foreach my $sf (keys %{ $modify_record->{$f} }) {
641 $log->debug("subfield: $sf");
642
643 foreach my $from (keys %{ $modify_record->{$f}->{$sf} }) {
644 my $to = $modify_record->{$f}->{$sf}->{$from};
645 #die "no field?" unless defined($to);
646 my $d = "|$from| -> |$to|";
647 $log->debug("transform: $d");
648
649 my $regex = _get_regex($sf,$from,$to);
650 push @{ $regexpes->{$f} }, { regex => $regex, debug => $d };
651 $log->debug("regex: $regex");
652 }
653 }
654 }
655
656 return $regexpes;
657 }
658
659 =head2 modify_file_regexps
660
661 Generate hash with regexpes to be applied using L<filter> from
662 pseudo hash/yaml format for regex mappings.
663
664 It should be obvious:
665
666 200
667 '^a'
668 ' : ' => '^e'
669 ' = ' => '^d'
670
671 In field I<200> find C<'^a'> and then C<' : '>, and replace it with C<'^e'>.
672 In field I<200> find C<'^a'> and then C<' = '>, and replace it with C<'^d'>.
673
674 my $regexpes = $input->modify_file_regexps( 'conf/modify/common.pl' );
675
676 On undef path it will just return.
677
678 =cut
679
680 sub modify_file_regexps {
681 my $self = shift;
682
683 my $modify_path = shift || return;
684
685 my $log = $self->_get_logger();
686
687 my $regexpes;
688
689 CORE::open(my $fh, $modify_path) || $log->logdie("can't open modify file $modify_path: $!");
690
691 my ($f,$sf);
692
693 while(<$fh>) {
694 chomp;
695 next if (/^#/ || /^\s*$/);
696
697 if (/^\s*(\d+)\s*$/) {
698 $f = $1;
699 $log->debug("field: $f");
700 next;
701 } elsif (/^\s*'([^']*)'\s*$/) {
702 $sf = $1;
703 $log->die("can't define subfiled before field in: $_") unless ($f);
704 $log->debug("subfield: $sf");
705 } elsif (/^\s*'([^']*)'\s*=>\s*'([^']*)'\s*$/) {
706 my ($from,$to) = ($1, $2);
707
708 $log->debug("transform: |$from| -> |$to|");
709
710 my $regex = _get_regex($sf,$from,$to);
711 push @{ $regexpes->{$f} }, {
712 regex => $regex,
713 file => $modify_path,
714 line => $.,
715 };
716 $log->debug("regex: $regex");
717 }
718 }
719
720 return $regexpes;
721 }
722
723 =head1 AUTHOR
724
725 Dobrica Pavlinusic, C<< <dpavlin@rot13.org> >>
726
727 =head1 COPYRIGHT & LICENSE
728
729 Copyright 2005-2006 Dobrica Pavlinusic, All Rights Reserved.
730
731 This program is free software; you can redistribute it and/or modify it
732 under the same terms as Perl itself.
733
734 =cut
735
736 1; # End of WebPAC::Input

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