--- trunk/lib/WebPAC/Input.pm 2005/06/25 20:23:23 1 +++ trunk/lib/WebPAC/Input.pm 2006/08/26 12:00:36 625 @@ -3,67 +3,618 @@ use warnings; use strict; +use blib; + +use WebPAC::Common; +use base qw/WebPAC::Common/; +use Data::Dumper; +use Encode qw/from_to/; + =head1 NAME -WebPAC::Input - The great new WebPAC::Input! +WebPAC::Input - read different file formats into WebPAC =head1 VERSION -Version 0.01 +Version 0.11 =cut -our $VERSION = '0.01'; +our $VERSION = '0.11'; =head1 SYNOPSIS -Quick summary of what the module does. +This module implements input as database which have fixed and known +I while indexing and single unique numeric identifier for database +position ranging from 1 to I. + +Simply, something that is indexed by unmber from 1 .. I. + +Examples of such databases are CDS/ISIS files, MARC files, lines in +text file, and so on. + +Specific file formats are implemented using low-level interface modules, +located in C namespace which export C, +C and optional C functions. Perhaps a little code snippet. - use WebPAC::Input; + use WebPAC::Input; - my $foo = WebPAC::Input->new(); - ... + my $db = WebPAC::Input->new( + module => 'WebPAC::Input::ISIS', + low_mem => 1, + ); + + $db->open( path => '/path/to/database' ); + print "database size: ",$db->size,"\n"; + while (my $rec = $db->fetch) { + # do something with $rec + } -=head1 EXPORT -A list of functions that can be exported. You can delete this section -if you don't export anything, such as for a purely object-oriented module. =head1 FUNCTIONS -=head2 function1 +=head2 new + +Create new input database object. + + my $db = new WebPAC::Input( + module => 'WebPAC::Input::MARC', + encoding => 'ISO-8859-2', + low_mem => 1, + recode => 'char pairs', + no_progress_bar => 1, + ); + +C is low-level file format module. See L and +L. + +Optional parametar C specify application code page (which will be +used internally). This should probably be your terminal encoding, and by +default, it C. + +Default is not to use C options (see L below). + +C is optional string constisting of character or words pairs that +should be replaced in input stream. + +C disables progress bar output on C + +This function will also call low-level C if it exists with same +parametars. =cut -sub function1 { +sub new { + my $class = shift; + my $self = {@_}; + bless($self, $class); + + my $log = $self->_get_logger; + + $log->logconfess("code_page argument is not suppored any more. change it to encoding") if ($self->{lookup}); + $log->logconfess("lookup argument is not suppored any more. rewrite call to lookup_ref") if ($self->{lookup}); + + $log->logconfess("specify low-level file format module") unless ($self->{module}); + my $module = $self->{module}; + $module =~ s#::#/#g; + $module .= '.pm'; + $log->debug("require low-level module $self->{module} from $module"); + + require $module; + #eval $self->{module} .'->import'; + + # check if required subclasses are implemented + foreach my $subclass (qw/open_db fetch_rec init/) { + my $n = $self->{module} . '::' . $subclass; + if (! defined &{ $n }) { + my $missing = "missing $subclass in $self->{module}"; + $self->{$subclass} = sub { $log->logwarn($missing) }; + } else { + $self->{$subclass} = \&{ $n }; + } + } + + if ($self->{init}) { + $log->debug("calling init"); + $self->{init}->($self, @_); + } + + $self->{'encoding'} ||= 'ISO-8859-2'; + + # running with low_mem flag? well, use DBM::Deep then. + if ($self->{'low_mem'}) { + $log->info("running with low_mem which impacts performance (<32 Mb memory usage)"); + + my $db_file = "data.db"; + + if (-e $db_file) { + unlink $db_file or $log->logdie("can't remove '$db_file' from last run"); + $log->debug("removed '$db_file' from last run"); + } + + require DBM::Deep; + + my $db = new DBM::Deep $db_file; + + $log->logdie("DBM::Deep error: $!") unless ($db); + + if ($db->error()) { + $log->logdie("can't open '$db_file' under low_mem: ",$db->error()); + } else { + $log->debug("using file '$db_file' for DBM::Deep"); + } + + $self->{'db'} = $db; + } + + $self ? return $self : return undef; } -=head2 function2 +=head2 open + +This function will read whole database in memory and produce lookups. + + $input->open( + path => '/path/to/database/file', + code_page => 'cp852', + limit => 500, + offset => 6000, + lookup => $lookup_obj, + stats => 1, + lookup_ref => sub { + my ($k,$v) = @_; + # store lookup $k => $v + }, + modify_records => { + 900 => { '^a' => { ' : ' => '^b' } }, + 901 => { '*' => { '^b' => ' ; ' } }, + }, + ); + +By default, C is assumed to be C. + +C is optional parametar to position at some offset before reading from database. + +C is optional parametar to read just C records from database + +C create optional report about usage of fields and subfields + +C is closure to call when adding C<< key => 'value' >> combinations to +lookup. + +C specify mapping from subfields to delimiters or from +delimiters to subfields, as well as oprations on fields (if subfield is +defined as C<*>. + +Returns size of database, regardless of C and C +parametars, see also C. =cut -sub function2 { +sub open { + my $self = shift; + my $arg = {@_}; + + my $log = $self->_get_logger(); + + $log->logconfess("lookup argument is not suppored any more. rewrite call to lookup_coderef") if ($arg->{lookup}); + $log->logconfess("lookup_coderef must be CODE, not ",ref($arg->{lookup_coderef})) + if ($arg->{lookup_coderef} && ref($arg->{lookup_coderef}) ne 'CODE'); + + $log->logcroak("need path") if (! $arg->{'path'}); + my $code_page = $arg->{'code_page'} || 'cp852'; + + # store data in object + $self->{'input_code_page'} = $code_page; + foreach my $v (qw/path offset limit/) { + $self->{$v} = $arg->{$v} if ($arg->{$v}); + } + + my $filter_ref; + my $recode_regex; + my $recode_map; + + if ($self->{recode}) { + my @r = split(/\s/, $self->{recode}); + if ($#r % 2 != 1) { + $log->logwarn("recode needs even number of elements (some number of valid pairs)"); + } else { + while (@r) { + my $from = shift @r; + my $to = shift @r; + $recode_map->{$from} = $to; + } + + $recode_regex = join '|' => keys %{ $recode_map }; + + $log->debug("using recode regex: $recode_regex"); + } + + } + + my $rec_regex = $self->modify_record_regexps(%{ $arg->{modify_records} }); + $log->debug("rec_regex: ", Dumper($rec_regex)); + + my ($db, $size) = $self->{open_db}->( $self, + path => $arg->{path}, +# filter => sub { +# my ($l,$f_nr) = @_; +# return unless defined($l); +# from_to($l, $code_page, $self->{'encoding'}); +# $l =~ s/($recode_regex)/$recode_map->{$1}/g if ($recode_regex && $recode_map); +# return $l; +# }, + %{ $arg }, + ); + + unless (defined($db)) { + $log->logwarn("can't open database $arg->{path}, skipping..."); + return; + } + + unless ($size) { + $log->logwarn("no records in database $arg->{path}, skipping..."); + return; + } + + my $from_rec = 1; + my $to_rec = $size; + + if (my $s = $self->{offset}) { + $log->debug("skipping to MFN $s"); + $from_rec = $s; + } else { + $self->{offset} = $from_rec; + } + + if ($self->{limit}) { + $log->debug("limiting to ",$self->{limit}," records"); + $to_rec = $from_rec + $self->{limit} - 1; + $to_rec = $size if ($to_rec > $size); + } + + # store size for later + $self->{size} = ($to_rec - $from_rec) ? ($to_rec - $from_rec + 1) : 0; + + $log->info("processing $self->{size}/$size records [$from_rec-$to_rec] convert $code_page -> $self->{encoding}", $self->{stats} ? ' [stats]' : ''); + + # read database + for (my $pos = $from_rec; $pos <= $to_rec; $pos++) { + + $log->debug("position: $pos\n"); + + my $rec = $self->{fetch_rec}->($self, $db, $pos, sub { + my ($l,$f_nr) = @_; +# return unless defined($l); +# return $l unless ($rec_regex && $f_nr); + + $log->debug("-=> $f_nr ## $l"); + + # codepage conversion and recode_regex +# from_to($l, $code_page, $self->{'encoding'}); + from_to($l, $code_page, 'utf-8'); + $l =~ s/($recode_regex)/$recode_map->{$1}/g if ($recode_regex && $recode_map); + + # apply regexps + if ($rec_regex && defined($rec_regex->{$f_nr})) { + $log->logconfess("regexps->{$f_nr} must be ARRAY") if (ref($rec_regex->{$f_nr}) ne 'ARRAY'); + my $c = 0; + foreach my $r (@{ $rec_regex->{$f_nr} }) { + #$log->debug("\$l = $l\neval \$l =~ $r"); + eval '$l =~ ' . $r; + $log->error("error applying regex: $r") if ($@); + } + } + + $log->debug("<=- $f_nr ## $l"); + return $l; + }); + + $log->debug(sub { Dumper($rec) }); + + if (! $rec) { + $log->warn("record $pos empty? skipping..."); + next; + } + + # store + if ($self->{low_mem}) { + $self->{db}->put($pos, $rec); + } else { + $self->{data}->{$pos} = $rec; + } + + # create lookup + $arg->{'lookup_coderef'}->( $rec ) if ($rec && $arg->{'lookup_coderef'}); + + # update counters for statistics + if ($self->{stats}) { + + # fetch clean record with regexpes applied for statistics + my $rec = $self->{fetch_rec}->($self, $db, $pos); + + foreach my $fld (keys %{ $rec }) { + $self->{_stats}->{fld}->{ $fld }++; + + $log->logdie("invalid record fild $fld, not ARRAY") + unless (ref($rec->{ $fld }) eq 'ARRAY'); + + foreach my $row (@{ $rec->{$fld} }) { + + if (ref($row) eq 'HASH') { + + foreach my $sf (keys %{ $row }) { + next if ($sf eq 'subfields'); + $self->{_stats}->{sf}->{ $fld }->{ $sf }->{count}++; + $self->{_stats}->{sf}->{ $fld }->{ $sf }->{repeatable}++ + if (ref($row->{$sf}) eq 'ARRAY'); + } + + } else { + $self->{_stats}->{repeatable}->{ $fld }++; + } + } + } + } + + $self->progress_bar($pos,$to_rec) unless ($self->{no_progress_bar}); + + } + + $self->{pos} = -1; + $self->{last_pcnt} = 0; + + # store max mfn and return it. + $self->{max_pos} = $to_rec; + $log->debug("max_pos: $to_rec"); + + return $size; } -=head1 AUTHOR +=head2 fetch + +Fetch next record from database. It will also displays progress bar. + + my $rec = $isis->fetch; + +Record from this function should probably go to C for +normalisation. + +=cut + +sub fetch { + my $self = shift; + + my $log = $self->_get_logger(); + + $log->logconfess("it seems that you didn't load database!") unless ($self->{pos}); + + if ($self->{pos} == -1) { + $self->{pos} = $self->{offset}; + } else { + $self->{pos}++; + } + + my $mfn = $self->{pos}; + + if ($mfn > $self->{max_pos}) { + $self->{pos} = $self->{max_pos}; + $log->debug("at EOF"); + return; + } + + $self->progress_bar($mfn,$self->{max_pos}) unless ($self->{no_progress_bar}); + + my $rec; + + if ($self->{low_mem}) { + $rec = $self->{db}->get($mfn); + } else { + $rec = $self->{data}->{$mfn}; + } + + $rec ||= 0E0; +} + +=head2 pos + +Returns current record number (MFN). + + print $isis->pos; + +First record in database has position 1. + +=cut + +sub pos { + my $self = shift; + return $self->{pos}; +} -Dobrica Pavlinusic, C<< >> -=head1 BUGS +=head2 size -Please report any bugs or feature requests to -C, or through the web interface at -L. -I will be notified, and then you'll automatically be notified of progress on -your bug as I make changes. +Returns number of records in database -=head1 ACKNOWLEDGEMENTS + print $isis->size; + +Result from this function can be used to loop through all records + + foreach my $mfn ( 1 ... $isis->size ) { ... } + +because it takes into account C and C. + +=cut + +sub size { + my $self = shift; + return $self->{size}; +} + +=head2 seek + +Seek to specified MFN in file. + + $isis->seek(42); + +First record in database has position 1. + +=cut + +sub seek { + my $self = shift; + my $pos = shift || return; + + my $log = $self->_get_logger(); + + if ($pos < 1) { + $log->warn("seek before first record"); + $pos = 1; + } elsif ($pos > $self->{max_pos}) { + $log->warn("seek beyond last record"); + $pos = $self->{max_pos}; + } + + return $self->{pos} = (($pos - 1) || -1); +} + +=head2 stats + +Dump statistics about field and subfield usage + + print $input->stats; + +=cut + +sub stats { + my $self = shift; + + my $log = $self->_get_logger(); + + my $s = $self->{_stats}; + if (! $s) { + $log->warn("called stats, but there is no statistics collected"); + return; + } + + my $max_fld = 0; + + my $out = join("\n", + map { + my $f = $_ || die "no field"; + my $v = $s->{fld}->{$f} || die "no s->{fld}->{$f}"; + $max_fld = $v if ($v > $max_fld); + + my $o = sprintf("%4s %d ~", $f, $v); + + if (defined($s->{sf}->{$f})) { + map { + $o .= sprintf(" %s:%d%s", $_, + $s->{sf}->{$f}->{$_}->{count}, + $s->{sf}->{$f}->{$_}->{repeatable} ? '*' : '', + ); + } sort keys %{ $s->{sf}->{$f} }; + } + + if (my $v_r = $s->{repeatable}->{$f}) { + $o .= " ($v_r)" if ($v_r != $v); + } + + $o; + } sort { $a cmp $b } keys %{ $s->{fld} } + ); + + $log->debug( sub { Dumper($s) } ); + + return $out; +} + +=head2 modify_record_regexps + +Generate hash with regexpes to be applied using L. + + my $regexpes = $input->modify_record_regexps( + 900 => { '^a' => { ' : ' => '^b' } }, + 901 => { '*' => { '^b' => ' ; ' } }, + ); + +=cut + +sub modify_record_regexps { + my $self = shift; + my $modify_record = {@_}; + + my $regexpes; + + foreach my $f (keys %$modify_record) { +warn "--- f: $f\n"; + foreach my $sf (keys %{ $modify_record->{$f} }) { +warn "---- sf: $sf\n"; + foreach my $from (keys %{ $modify_record->{$f}->{$sf} }) { + my $to = $modify_record->{$f}->{$sf}->{$from}; + #die "no field?" unless defined($to); +warn "----- transform: |$from| -> |$to|\n"; + + if ($sf =~ /^\^/) { + my $regex = + 's/\Q'. $sf .'\E([^\^]+)\Q'. $from .'\E([^\^]+)/'. $sf .'$1'. $to .'$2/g'; + push @{ $regexpes->{$f} }, $regex; +warn ">>>>> $regex [sf]\n"; + } else { + my $regex = + 's/\Q'. $from .'\E/'. $to .'/g'; + push @{ $regexpes->{$f} }, $regex; +warn ">>>>> $regex [global]\n"; + } + + } + } + } + + return $regexpes; +} + +=head1 MEMORY USAGE + +C options is double-edged sword. If enabled, WebPAC +will run on memory constraint machines (which doesn't have enough +physical RAM to create memory structure for whole source database). + +If your machine has 512Mb or more of RAM and database is around 10000 records, +memory shouldn't be an issue. If you don't have enough physical RAM, you +might consider using virtual memory (if your operating system is handling it +well, like on FreeBSD or Linux) instead of dropping to L to handle +parsed structure of ISIS database (this is what C option does). + +Hitting swap at end of reading source database is probably o.k. However, +hitting swap before 90% will dramatically decrease performance and you will +be better off with C and using rest of availble memory for +operating system disk cache (Linux is particuallary good about this). +However, every access to database record will require disk access, so +generation phase will be slower 10-100 times. + +Parsed structures are essential - you just have option to trade RAM memory +(which is fast) for disk space (which is slow). Be sure to have planty of +disk space if you are using C and thus L. + +However, when WebPAC is running on desktop machines (or laptops :-), it's +highly undesireable for system to start swapping. Using C option can +reduce WecPAC memory usage to around 64Mb for same database with lookup +fields and sorted indexes which stay in RAM. Performance will suffer, but +memory usage will really be minimal. It might be also more confortable to +run WebPAC reniced on those machines. + + +=head1 AUTHOR + +Dobrica Pavlinusic, C<< >> =head1 COPYRIGHT & LICENSE -Copyright 2005 Dobrica Pavlinusic, All Rights Reserved. +Copyright 2005-2006 Dobrica Pavlinusic, All Rights Reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.