| 3 |
use warnings; |
use warnings; |
| 4 |
use strict; |
use strict; |
| 5 |
|
|
| 6 |
|
use WebPAC::Common; |
| 7 |
|
use base qw/WebPAC::Common/; |
| 8 |
|
use Text::Iconv; |
| 9 |
|
|
| 10 |
=head1 NAME |
=head1 NAME |
| 11 |
|
|
| 12 |
WebPAC::Input - The great new WebPAC::Input! |
WebPAC::Input - read different file formats into WebPAC |
| 13 |
|
|
| 14 |
=head1 VERSION |
=head1 VERSION |
| 15 |
|
|
| 16 |
Version 0.01 |
Version 0.03 |
| 17 |
|
|
| 18 |
=cut |
=cut |
| 19 |
|
|
| 20 |
our $VERSION = '0.01'; |
our $VERSION = '0.03'; |
| 21 |
|
|
| 22 |
=head1 SYNOPSIS |
=head1 SYNOPSIS |
| 23 |
|
|
| 24 |
Quick summary of what the module does. |
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 |
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|
| 28 |
|
Simply, something that is indexed by unmber from 1 .. I<size>. |
| 29 |
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|
| 30 |
|
Examples of such databases are CDS/ISIS files, MARC files, lines in |
| 31 |
|
text file, and so on. |
| 32 |
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|
| 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. |
Perhaps a little code snippet. |
| 38 |
|
|
| 39 |
use WebPAC::Input; |
use WebPAC::Input; |
| 40 |
|
|
| 41 |
my $foo = WebPAC::Input->new(); |
my $db = WebPAC::Input->new( |
| 42 |
... |
module => 'WebPAC::Input::ISIS', |
| 43 |
|
config => $config, |
| 44 |
|
lookup => $lookup_obj, |
| 45 |
|
low_mem => 1, |
| 46 |
|
); |
| 47 |
|
|
| 48 |
|
$db->open('/path/to/database'); |
| 49 |
|
print "database size: ",$db->size,"\n"; |
| 50 |
|
while (my $rec = $db->fetch) { |
| 51 |
|
} |
| 52 |
|
|
|
=head1 EXPORT |
|
| 53 |
|
|
|
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. |
|
| 54 |
|
|
| 55 |
=head1 FUNCTIONS |
=head1 FUNCTIONS |
| 56 |
|
|
| 57 |
=head2 function1 |
=head2 new |
| 58 |
|
|
| 59 |
|
Create new input database object. |
| 60 |
|
|
| 61 |
|
my $db = new WebPAC::Input( |
| 62 |
|
module => 'WebPAC::Input::MARC', |
| 63 |
|
code_page => 'ISO-8859-2', |
| 64 |
|
low_mem => 1, |
| 65 |
|
); |
| 66 |
|
|
| 67 |
|
C<module> is low-level file format module. See L<WebPAC::Input::Isis> and |
| 68 |
|
L<WebPAC::Input::MARC>. |
| 69 |
|
|
| 70 |
|
Optional parametar C<code_page> specify application code page (which will be |
| 71 |
|
used internally). This should probably be your terminal encoding, and by |
| 72 |
|
default, it C<ISO-8859-2>. |
| 73 |
|
|
| 74 |
|
Default is not to use C<low_mem> options (see L<MEMORY USAGE> below). |
| 75 |
|
|
| 76 |
|
This function will also call low-level C<init> if it exists with same |
| 77 |
|
parametars. |
| 78 |
|
|
| 79 |
=cut |
=cut |
| 80 |
|
|
| 81 |
sub function1 { |
sub new { |
| 82 |
|
my $class = shift; |
| 83 |
|
my $self = {@_}; |
| 84 |
|
bless($self, $class); |
| 85 |
|
|
| 86 |
|
my $log = $self->_get_logger; |
| 87 |
|
|
| 88 |
|
$log->logconfess("specify low-level file format module") unless ($self->{module}); |
| 89 |
|
my $module = $self->{module}; |
| 90 |
|
$module =~ s#::#/#g; |
| 91 |
|
$module .= '.pm'; |
| 92 |
|
$log->debug("require low-level module $self->{module} from $module"); |
| 93 |
|
|
| 94 |
|
require $module; |
| 95 |
|
#eval $self->{module} .'->import'; |
| 96 |
|
|
| 97 |
|
# check if required subclasses are implemented |
| 98 |
|
foreach my $subclass (qw/open_db fetch_rec init/) { |
| 99 |
|
my $n = $self->{module} . '::' . $subclass; |
| 100 |
|
if (! defined &{ $n }) { |
| 101 |
|
my $missing = "missing $subclass in $self->{module}"; |
| 102 |
|
$self->{$subclass} = sub { $log->logwarn($missing) }; |
| 103 |
|
} else { |
| 104 |
|
$self->{$subclass} = \&{ $n }; |
| 105 |
|
} |
| 106 |
|
} |
| 107 |
|
|
| 108 |
|
if ($self->{init}) { |
| 109 |
|
$log->debug("calling init"); |
| 110 |
|
$self->{init}->($self, @_); |
| 111 |
|
} |
| 112 |
|
|
| 113 |
|
$self->{'code_page'} ||= 'ISO-8859-2'; |
| 114 |
|
|
| 115 |
|
# running with low_mem flag? well, use DBM::Deep then. |
| 116 |
|
if ($self->{'low_mem'}) { |
| 117 |
|
$log->info("running with low_mem which impacts performance (<32 Mb memory usage)"); |
| 118 |
|
|
| 119 |
|
my $db_file = "data.db"; |
| 120 |
|
|
| 121 |
|
if (-e $db_file) { |
| 122 |
|
unlink $db_file or $log->logdie("can't remove '$db_file' from last run"); |
| 123 |
|
$log->debug("removed '$db_file' from last run"); |
| 124 |
|
} |
| 125 |
|
|
| 126 |
|
require DBM::Deep; |
| 127 |
|
|
| 128 |
|
my $db = new DBM::Deep $db_file; |
| 129 |
|
|
| 130 |
|
$log->logdie("DBM::Deep error: $!") unless ($db); |
| 131 |
|
|
| 132 |
|
if ($db->error()) { |
| 133 |
|
$log->logdie("can't open '$db_file' under low_mem: ",$db->error()); |
| 134 |
|
} else { |
| 135 |
|
$log->debug("using file '$db_file' for DBM::Deep"); |
| 136 |
|
} |
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|
|
| 138 |
|
$self->{'db'} = $db; |
| 139 |
|
} |
| 140 |
|
|
| 141 |
|
$self ? return $self : return undef; |
| 142 |
} |
} |
| 143 |
|
|
| 144 |
=head2 function2 |
=head2 open |
| 145 |
|
|
| 146 |
|
This function will read whole database in memory and produce lookups. |
| 147 |
|
|
| 148 |
|
$input->open( |
| 149 |
|
path => '/path/to/database/file', |
| 150 |
|
code_page => '852', |
| 151 |
|
limit => 500, |
| 152 |
|
offset => 6000, |
| 153 |
|
lookup => $lookup_obj, |
| 154 |
|
); |
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|
|
| 156 |
|
By default, C<code_page> is assumed to be C<852>. |
| 157 |
|
|
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|
C<offset> is optional parametar to position at some offset before reading from database. |
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|
| 160 |
|
C<limit> is optional parametar to read just C<limit> records from database |
| 161 |
|
|
| 162 |
|
Returns size of database, regardless of C<offset> and C<limit> |
| 163 |
|
parametars, see also C<size>. |
| 164 |
|
|
| 165 |
=cut |
=cut |
| 166 |
|
|
| 167 |
sub function2 { |
sub open { |
| 168 |
|
my $self = shift; |
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|
my $arg = {@_}; |
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|
|
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|
my $log = $self->_get_logger(); |
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|
|
| 173 |
|
$log->logcroak("need path") if (! $arg->{'path'}); |
| 174 |
|
my $code_page = $arg->{'code_page'} || '852'; |
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|
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|
# store data in object |
| 177 |
|
$self->{'input_code_page'} = $code_page; |
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|
foreach my $v (qw/path offset limit/) { |
| 179 |
|
$self->{$v} = $arg->{$v} if ($arg->{$v}); |
| 180 |
|
} |
| 181 |
|
|
| 182 |
|
# create Text::Iconv object |
| 183 |
|
$self->{iconv} = Text::Iconv->new($code_page,$self->{'code_page'}); |
| 184 |
|
|
| 185 |
|
my ($db, $size) = $self->{open_db}->( $self, |
| 186 |
|
path => $arg->{path}, |
| 187 |
|
); |
| 188 |
|
|
| 189 |
|
unless ($db) { |
| 190 |
|
$log->logwarn("can't open database $arg->{path}, skipping..."); |
| 191 |
|
return; |
| 192 |
|
} |
| 193 |
|
|
| 194 |
|
unless ($size) { |
| 195 |
|
$log->logwarn("no records in database $arg->{path}, skipping..."); |
| 196 |
|
return; |
| 197 |
|
} |
| 198 |
|
|
| 199 |
|
my $offset = 1; |
| 200 |
|
my $limit = $size; |
| 201 |
|
|
| 202 |
|
if (my $s = $self->{offset}) { |
| 203 |
|
$log->info("skipping to MFN $s"); |
| 204 |
|
$offset = $s; |
| 205 |
|
} else { |
| 206 |
|
$self->{offset} = $offset; |
| 207 |
|
} |
| 208 |
|
|
| 209 |
|
if ($self->{limit}) { |
| 210 |
|
$log->debug("limiting to ",$self->{limit}," records"); |
| 211 |
|
$limit = $offset + $self->{limit} - 1; |
| 212 |
|
$limit = $size if ($limit > $size); |
| 213 |
|
} |
| 214 |
|
|
| 215 |
|
# store size for later |
| 216 |
|
$self->{size} = ($limit - $offset) ? ($limit - $offset + 1) : 0; |
| 217 |
|
|
| 218 |
|
$log->info("processing $self->{size} records in $code_page, convert to $self->{code_page}"); |
| 219 |
|
|
| 220 |
|
# read database |
| 221 |
|
for (my $pos = $offset; $pos <= $limit; $pos++) { |
| 222 |
|
|
| 223 |
|
$log->debug("position: $pos\n"); |
| 224 |
|
|
| 225 |
|
my $rec = $self->{fetch_rec}->($self, $db, $pos ); |
| 226 |
|
|
| 227 |
|
if (! $rec) { |
| 228 |
|
$log->warn("record $pos empty? skipping..."); |
| 229 |
|
next; |
| 230 |
|
} |
| 231 |
|
|
| 232 |
|
# store |
| 233 |
|
if ($self->{low_mem}) { |
| 234 |
|
$self->{db}->put($pos, $rec); |
| 235 |
|
} else { |
| 236 |
|
$self->{data}->{$pos} = $rec; |
| 237 |
|
} |
| 238 |
|
|
| 239 |
|
# create lookup |
| 240 |
|
$self->{'lookup'}->add( $rec ) if ($rec && $self->{'lookup'}); |
| 241 |
|
|
| 242 |
|
$self->progress_bar($pos,$limit); |
| 243 |
|
|
| 244 |
|
} |
| 245 |
|
|
| 246 |
|
$self->{pos} = -1; |
| 247 |
|
$self->{last_pcnt} = 0; |
| 248 |
|
|
| 249 |
|
# store max mfn and return it. |
| 250 |
|
$self->{max_pos} = $limit; |
| 251 |
|
$log->debug("max_pos: $limit"); |
| 252 |
|
|
| 253 |
|
return $size; |
| 254 |
} |
} |
| 255 |
|
|
| 256 |
=head1 AUTHOR |
=head2 fetch |
| 257 |
|
|
| 258 |
Dobrica Pavlinusic, C<< <dpavlin@rot13.org> >> |
Fetch next record from database. It will also displays progress bar. |
| 259 |
|
|
| 260 |
|
my $rec = $isis->fetch; |
| 261 |
|
|
| 262 |
|
Record from this function should probably go to C<data_structure> for |
| 263 |
|
normalisation. |
| 264 |
|
|
| 265 |
|
=cut |
| 266 |
|
|
| 267 |
=head1 BUGS |
sub fetch { |
| 268 |
|
my $self = shift; |
| 269 |
|
|
| 270 |
Please report any bugs or feature requests to |
my $log = $self->_get_logger(); |
|
C<bug-webpac-input@rt.cpan.org>, or through the web interface at |
|
|
L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=WebPAC>. |
|
|
I will be notified, and then you'll automatically be notified of progress on |
|
|
your bug as I make changes. |
|
| 271 |
|
|
| 272 |
=head1 ACKNOWLEDGEMENTS |
$log->logconfess("it seems that you didn't load database!") unless ($self->{pos}); |
| 273 |
|
|
| 274 |
|
if ($self->{pos} == -1) { |
| 275 |
|
$self->{pos} = $self->{offset}; |
| 276 |
|
} else { |
| 277 |
|
$self->{pos}++; |
| 278 |
|
} |
| 279 |
|
|
| 280 |
|
my $mfn = $self->{pos}; |
| 281 |
|
|
| 282 |
|
if ($mfn > $self->{max_pos}) { |
| 283 |
|
$self->{pos} = $self->{max_pos}; |
| 284 |
|
$log->debug("at EOF"); |
| 285 |
|
return; |
| 286 |
|
} |
| 287 |
|
|
| 288 |
|
$self->progress_bar($mfn,$self->{max_pos}); |
| 289 |
|
|
| 290 |
|
my $rec; |
| 291 |
|
|
| 292 |
|
if ($self->{low_mem}) { |
| 293 |
|
$rec = $self->{db}->get($mfn); |
| 294 |
|
} else { |
| 295 |
|
$rec = $self->{data}->{$mfn}; |
| 296 |
|
} |
| 297 |
|
|
| 298 |
|
$rec ||= 0E0; |
| 299 |
|
} |
| 300 |
|
|
| 301 |
|
=head2 pos |
| 302 |
|
|
| 303 |
|
Returns current record number (MFN). |
| 304 |
|
|
| 305 |
|
print $isis->pos; |
| 306 |
|
|
| 307 |
|
First record in database has position 1. |
| 308 |
|
|
| 309 |
|
=cut |
| 310 |
|
|
| 311 |
|
sub pos { |
| 312 |
|
my $self = shift; |
| 313 |
|
return $self->{pos}; |
| 314 |
|
} |
| 315 |
|
|
| 316 |
|
|
| 317 |
|
=head2 size |
| 318 |
|
|
| 319 |
|
Returns number of records in database |
| 320 |
|
|
| 321 |
|
print $isis->size; |
| 322 |
|
|
| 323 |
|
Result from this function can be used to loop through all records |
| 324 |
|
|
| 325 |
|
foreach my $mfn ( 1 ... $isis->size ) { ... } |
| 326 |
|
|
| 327 |
|
because it takes into account C<offset> and C<limit>. |
| 328 |
|
|
| 329 |
|
=cut |
| 330 |
|
|
| 331 |
|
sub size { |
| 332 |
|
my $self = shift; |
| 333 |
|
return $self->{size}; |
| 334 |
|
} |
| 335 |
|
|
| 336 |
|
=head2 seek |
| 337 |
|
|
| 338 |
|
Seek to specified MFN in file. |
| 339 |
|
|
| 340 |
|
$isis->seek(42); |
| 341 |
|
|
| 342 |
|
First record in database has position 1. |
| 343 |
|
|
| 344 |
|
=cut |
| 345 |
|
|
| 346 |
|
sub seek { |
| 347 |
|
my $self = shift; |
| 348 |
|
my $pos = shift || return; |
| 349 |
|
|
| 350 |
|
my $log = $self->_get_logger(); |
| 351 |
|
|
| 352 |
|
if ($pos < 1) { |
| 353 |
|
$log->warn("seek before first record"); |
| 354 |
|
$pos = 1; |
| 355 |
|
} elsif ($pos > $self->{max_pos}) { |
| 356 |
|
$log->warn("seek beyond last record"); |
| 357 |
|
$pos = $self->{max_pos}; |
| 358 |
|
} |
| 359 |
|
|
| 360 |
|
return $self->{pos} = (($pos - 1) || -1); |
| 361 |
|
} |
| 362 |
|
|
| 363 |
|
|
| 364 |
|
=head1 MEMORY USAGE |
| 365 |
|
|
| 366 |
|
C<low_mem> options is double-edged sword. If enabled, WebPAC |
| 367 |
|
will run on memory constraint machines (which doesn't have enough |
| 368 |
|
physical RAM to create memory structure for whole source database). |
| 369 |
|
|
| 370 |
|
If your machine has 512Mb or more of RAM and database is around 10000 records, |
| 371 |
|
memory shouldn't be an issue. If you don't have enough physical RAM, you |
| 372 |
|
might consider using virtual memory (if your operating system is handling it |
| 373 |
|
well, like on FreeBSD or Linux) instead of dropping to L<DBM::Deep> to handle |
| 374 |
|
parsed structure of ISIS database (this is what C<low_mem> option does). |
| 375 |
|
|
| 376 |
|
Hitting swap at end of reading source database is probably o.k. However, |
| 377 |
|
hitting swap before 90% will dramatically decrease performance and you will |
| 378 |
|
be better off with C<low_mem> and using rest of availble memory for |
| 379 |
|
operating system disk cache (Linux is particuallary good about this). |
| 380 |
|
However, every access to database record will require disk access, so |
| 381 |
|
generation phase will be slower 10-100 times. |
| 382 |
|
|
| 383 |
|
Parsed structures are essential - you just have option to trade RAM memory |
| 384 |
|
(which is fast) for disk space (which is slow). Be sure to have planty of |
| 385 |
|
disk space if you are using C<low_mem> and thus L<DBM::Deep>. |
| 386 |
|
|
| 387 |
|
However, when WebPAC is running on desktop machines (or laptops :-), it's |
| 388 |
|
highly undesireable for system to start swapping. Using C<low_mem> option can |
| 389 |
|
reduce WecPAC memory usage to around 64Mb for same database with lookup |
| 390 |
|
fields and sorted indexes which stay in RAM. Performance will suffer, but |
| 391 |
|
memory usage will really be minimal. It might be also more confortable to |
| 392 |
|
run WebPAC reniced on those machines. |
| 393 |
|
|
| 394 |
|
|
| 395 |
|
=head1 AUTHOR |
| 396 |
|
|
| 397 |
|
Dobrica Pavlinusic, C<< <dpavlin@rot13.org> >> |
| 398 |
|
|
| 399 |
=head1 COPYRIGHT & LICENSE |
=head1 COPYRIGHT & LICENSE |
| 400 |
|
|
Parent Directory
| 
Revision Log
| 
Patch