/usr/lib/x86_64-linux-gnu/perl5/5.26/MongoDB/GridFSBucket/DownloadStream.pm is in libmongodb-perl 1.8.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 | #
# Copyright 2009-2015 MongoDB, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
use strict;
use warnings;
package MongoDB::GridFSBucket::DownloadStream;
# ABSTRACT: File handle abstraction for downloading
use version;
our $VERSION = 'v1.8.1';
use Moo;
use Types::Standard qw(
Str
Bool
Maybe
HashRef
InstanceOf
FileHandle
);
use MongoDB::_Types qw(
NonNegNum
);
use List::Util qw(max min);
use namespace::clean -except => 'meta';
#pod =attr file_doc
#pod
#pod The file document for the file to be downloaded.
#pod
#pod Valid file documents typically include the following fields:
#pod
#pod =for :list
#pod * _id – a unique ID for this document, typically a L<MongoDB::OID> object.
#pod Legacy GridFS files may store this value as a different type.
#pod * length – the length of this stored file, in bytes
#pod * chunkSize – the size, in bytes, of each full data chunk of this file.
#pod * uploadDate – the date and time this file was added to GridFS, stored as a
#pod BSON datetime value and inflated per the bucket's
#pod L<bson_codec|MongoDB::GridFSBucket/bson_codec> attribute.
#pod * md5 – a hash of the contents of the stored file
#pod * filename – the name of this stored file; this does not need to be unique
#pod * metadata – any additional application-specific data
#pod * contentType – DEPRECATED
#pod * aliases – DEPRECATED
#pod
#pod =cut
has file_doc => (
is => 'ro',
isa => HashRef,
required => 1,
);
has _buffer => (
is => 'rwp',
isa => Str,
);
has _chunk_n => (
is => 'rwp',
isa => NonNegNum,
default => 0,
);
has _result => (
is => 'ro',
isa => Maybe [ InstanceOf ['MongoDB::QueryResult'] ],
required => 1,
);
# Currently this is always 0, but may be used to add
# optional rewinding in the future.
has _offset => (
is => 'rwp',
isa => NonNegNum,
default => 0,
);
has _closed => (
is => 'rwp',
isa => Bool,
default => 0,
);
#pod =method fh
#pod
#pod my $fh = $downloadstream->fh;
#pod while ( <$fh> ) {
#pod say($_);
#pod }
#pod
#pod Returns a new Perl file handle tied to this instance of DownloadStream that
#pod can be operated on with the built-in functions C<read>, C<readline>,
#pod C<getc>, C<eof>, C<fileno> and C<close>.
#pod
#pod B<Important notes>:
#pod
#pod Allowing one of these tied filehandles to fall out of scope will NOT cause
#pod close to be called. This is due to the way tied file handles are
#pod implemented in Perl. For close to be called implicitly, all tied
#pod filehandles and the original object must go out of scope.
#pod
#pod Each file handle retrieved this way is tied back to the same object, so
#pod calling close on multiple tied file handles and/or the original object will
#pod have the same effect as calling close on the original object multiple
#pod times.
#pod
#pod =cut
sub fh {
my ($self) = @_;
my $fh = IO::Handle->new();
tie *$fh, 'MongoDB::GridFSBucket::DownloadStream', $self;
return $fh;
}
sub _get_next_chunk {
my ($self) = @_;
return unless $self->_result && $self->_result->has_next;
my $chunk = $self->_result->next;
if ( $chunk->{'n'} != $self->_chunk_n ) {
MongoDB::GridFSError->throw(
sprintf(
'ChunkIsMissing: expected chunk %d but got chunk %d',
$self->_chunk_n, $chunk->{'n'},
)
);
}
my $last_chunk_n =
int( $self->file_doc->{'length'} / $self->file_doc->{'chunkSize'} );
my $expected_size =
$chunk->{'n'} == $last_chunk_n
? $self->file_doc->{'length'} % $self->file_doc->{'chunkSize'}
: $self->file_doc->{'chunkSize'};
if ( length $chunk->{'data'} != $expected_size ) {
MongoDB::GridFSError->throw(
sprintf(
"ChunkIsWrongSize: chunk %d from file with id %s has incorrect size %d, expected %d",
$self->_chunk_n,
$self->file_doc->{_id},
length $chunk->{'data'},
$expected_size,
)
);
}
$self->{_chunk_n} += 1;
$self->{_buffer} .= $chunk->{data}->{data};
}
sub _ensure_buffer {
my ($self) = @_;
if ( $self->{_buffer} ) { return length $self->{_buffer} }
$self->_get_next_chunk;
return length $self->{_buffer};
}
sub _readline_scalar {
my ($self) = @_;
# Special case for "slurp" mode
if ( !defined($/) ) {
return $self->_read_all;
}
return unless $self->_ensure_buffer;
my $newline_index;
while ( ( $newline_index = index $self->{_buffer}, $/ ) < 0 ) {
last unless $self->_get_next_chunk;
}
my $substr_len = $newline_index < 0 ? length $self->{_buffer} : $newline_index + 1;
return substr $self->{_buffer}, $self->_offset, $substr_len, '';
}
sub _read_all {
my ($self) = @_;
if ( $self->_closed ) {
warnings::warnif( 'closed',
'read called on a closed MongoDB::GridFSBucket::DownloadStream' );
return;
}
return unless $self->_result;
my $chunk_size = $self->file_doc->{'chunkSize'};
my $length = $self->file_doc->{'length'};
my $last_chunk_n = int( $length / $chunk_size );
my $last_chunk_size = $length % $chunk_size;
my @chunks = $self->_result->all;
for (my $i = 0; $i < @chunks; $i++ ) {
my $n = $chunks[$i]{n};
if ( $n != $i ) {
MongoDB::GridFSError->throw(
sprintf( 'ChunkIsMissing: expected chunk %d but got chunk %d', $i, $n)
);
}
my $expected_size = ($n == $last_chunk_n ? $last_chunk_size : $chunk_size);
if ( length $chunks[$i]{data}{data} != $expected_size ) {
MongoDB::GridFSError->throw(
sprintf(
"ChunkIsWrongSize: chunk %d of %d from file with id %s has incorrect size %d, expected %d",
$n,
$last_chunk_n,
$self->file_doc->{_id},
length $chunks[$i]{data}{data},
$expected_size,
)
);
}
}
return join( "", map { $_->{data}{data} } @chunks );
}
#pod =method close
#pod
#pod $stream->close
#pod
#pod Works like the builtin C<close>.
#pod
#pod B<Important notes:>
#pod
#pod =for :list
#pod * Calling close will also cause any tied file handles created for the
#pod stream to also close.
#pod * C<close> will be automatically called when a stream object is destroyed.
#pod * Calling C<close> repeately will warn.
#pod
#pod =cut
sub close {
my ($self) = @_;
if ( $self->_closed ) {
warn 'Attempted to close an already closed MongoDB::GridFSBucket::DownloadStream';
return;
}
$self->_set__closed(1);
$self->{_result} = undef;
$self->{_buffer} = undef;
$self->_set__chunk_n(0);
return 1;
}
#pod =method eof
#pod
#pod if ( $stream->eof() ) { ... }
#pod
#pod Works like the builtin C<eof>.
#pod
#pod =cut
sub eof {
my ($self) = @_;
return 1 if $self->_closed || !$self->_ensure_buffer;
return;
}
#pod =method fileno
#pod
#pod if ( $stream->fileno() ) { ... }
#pod
#pod Works like the builtin C<fileno>, but it returns -1 if the stream is open
#pod and undef if closed.
#pod
#pod =cut
sub fileno {
my ($self) = @_;
return if $self->_closed;
return -1;
}
#pod =method getc
#pod
#pod $char = $stream->getc();
#pod
#pod Works like the builtin C<getc>.
#pod
#pod =cut
sub getc {
my ($self) = @_;
my $char;
$self->read( $char, 1 );
return $char;
}
#pod =method read
#pod
#pod $data = $stream->read($buf, $length, $offset)
#pod
#pod Works like the builtin C<read>.
#pod
#pod =cut
sub read {
my $self = shift;
if ( $self->_closed ) {
warnings::warnif( 'closed',
'read called on a closed MongoDB::GridFSBucket::DownloadStream' );
return;
}
my $buffref = \$_[0];
my ( undef, $len, $offset ) = @_;
if ( $len < 0 ) {
MongoDB::UsageError->throw(
'Negative length passed to MongoDB::GridFSBucket::DownloadStream->read');
}
my $bufflen = length $$buffref;
$offset ||= 0;
$bufflen ||= 0;
$$buffref ||= '';
$offset = max( 0, $bufflen + $offset ) if $offset < 0;
if ( $offset > $bufflen ) {
$$buffref .= ( "\0" x ( $offset - $bufflen ) );
}
else {
substr $$buffref, $offset, $bufflen - $offset, '';
}
return 0 unless $self->_ensure_buffer;
while ( length $self->{_buffer} < $len ) { last unless $self->_get_next_chunk }
my $read_len = min( length $self->{_buffer}, $len );
$$buffref .= substr $self->{_buffer}, $self->_offset, $read_len, '';
return $read_len;
}
#pod =method readline
#pod
#pod $line = $stream->readline();
#pod @lines = $stream->readline();
#pod
#pod Works like the builtin C<readline>.
#pod
#pod =cut
sub readline {
my ($self) = @_;
if ( $self->_closed ) {
warnings::warnif( 'closed',
'readline called on a closed MongoDB::GridFSBucket::DownloadStream' );
return;
}
return $self->_readline_scalar unless wantarray;
my @result = ();
while ( my $line = $self->_readline_scalar ) {
push @result, $line;
}
return @result;
}
sub DEMOLISH {
my ($self) = @_;
$self->close unless $self->_closed;
}
# Magic tie methods
sub TIEHANDLE {
my ( $class, $self ) = @_;
return $self;
}
sub BINMODE {
my ( $self, $mode ) = @_;
if ( !$mode || $mode eq ':raw' ) {
return 1;
}
$! = "binmode for " . __PACKAGE__ . " only supports :raw mode.";
return
}
{
no warnings 'once';
*READ = \&read;
*READLINE = \&readline;
*CLOSE = \&close;
*GETC = \&getc;
*EOF = \&eof;
*FILENO = \&fileno;
}
my @unimplemented = qw(
PRINT
PRINTF
SEEK
TELL
WRITE
);
for my $u (@unimplemented) {
no strict 'refs';
my $l = $u eq 'WRITE' ? 'syswrite' : lc($u);
*{$u} = sub {
MongoDB::UsageError->throw( "$l() not available on " . __PACKAGE__ );
};
}
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
MongoDB::GridFSBucket::DownloadStream - File handle abstraction for downloading
=head1 VERSION
version v1.8.1
=head1 SYNOPSIS
# OO API
$stream = $bucket->open_download_stream($file_id)
while ( my $line = $stream->readline ) {
...
}
# Tied-handle API
$fh = $stream->fh;
while ( my $line = <$fh> ) {
...
}
=head1 DESCRIPTION
This class provides a file abstraction for downloading. You can stream
data from an object of this class using method calls or a tied-handle
interface.
=head1 ATTRIBUTES
=head2 file_doc
The file document for the file to be downloaded.
Valid file documents typically include the following fields:
=over 4
=item *
_id – a unique ID for this document, typically a L<MongoDB::OID> object. Legacy GridFS files may store this value as a different type.
=item *
length – the length of this stored file, in bytes
=item *
chunkSize – the size, in bytes, of each full data chunk of this file.
=item *
uploadDate – the date and time this file was added to GridFS, stored as a BSON datetime value and inflated per the bucket's L<bson_codec|MongoDB::GridFSBucket/bson_codec> attribute.
=item *
md5 – a hash of the contents of the stored file
=item *
filename – the name of this stored file; this does not need to be unique
=item *
metadata – any additional application-specific data
=item *
contentType – DEPRECATED
=item *
aliases – DEPRECATED
=back
=head1 METHODS
=head2 fh
my $fh = $downloadstream->fh;
while ( <$fh> ) {
say($_);
}
Returns a new Perl file handle tied to this instance of DownloadStream that
can be operated on with the built-in functions C<read>, C<readline>,
C<getc>, C<eof>, C<fileno> and C<close>.
B<Important notes>:
Allowing one of these tied filehandles to fall out of scope will NOT cause
close to be called. This is due to the way tied file handles are
implemented in Perl. For close to be called implicitly, all tied
filehandles and the original object must go out of scope.
Each file handle retrieved this way is tied back to the same object, so
calling close on multiple tied file handles and/or the original object will
have the same effect as calling close on the original object multiple
times.
=head2 close
$stream->close
Works like the builtin C<close>.
B<Important notes:>
=over 4
=item *
Calling close will also cause any tied file handles created for the stream to also close.
=item *
C<close> will be automatically called when a stream object is destroyed.
=item *
Calling C<close> repeately will warn.
=back
=head2 eof
if ( $stream->eof() ) { ... }
Works like the builtin C<eof>.
=head2 fileno
if ( $stream->fileno() ) { ... }
Works like the builtin C<fileno>, but it returns -1 if the stream is open
and undef if closed.
=head2 getc
$char = $stream->getc();
Works like the builtin C<getc>.
=head2 read
$data = $stream->read($buf, $length, $offset)
Works like the builtin C<read>.
=head2 readline
$line = $stream->readline();
@lines = $stream->readline();
Works like the builtin C<readline>.
=head1 AUTHORS
=over 4
=item *
David Golden <david@mongodb.com>
=item *
Rassi <rassi@mongodb.com>
=item *
Mike Friedman <friedo@friedo.com>
=item *
Kristina Chodorow <k.chodorow@gmail.com>
=item *
Florian Ragwitz <rafl@debian.org>
=back
=head1 COPYRIGHT AND LICENSE
This software is Copyright (c) 2018 by MongoDB, Inc.
This is free software, licensed under:
The Apache License, Version 2.0, January 2004
=cut
|