MongoDB::GridFSBucket::UploadStream - File handle abstraction for uploading
version v2.2.2
# OO API
$stream = $bucket->open_upload_stream("foo.txt");
$stream->print( $data );
$stream->close;
$id = $stream->id;
# Tied handle API
$fh = $stream->fh
print {$fh} $data;
close $fh;
This class provides a file abstraction for uploading. You can stream data
to an object of this class via methods or via a tied-handle interface.
Writes are buffered and sent in chunk-size units. When close is called,
all data will be flushed to the GridFS Bucket and the newly created file
will be visible.
The number of bytes per chunk. Defaults to the chunk_size_bytes of the
originating bucket object.
This will be stored in the chunkSize field of the file document on
a successful upload.
The filename to store the file under. Note that filenames are NOT necessarily unique.
This will be stored in the filename field of the file document on
a successful upload.
An optional hashref for storing arbitrary metadata about the file.
If defined, this will be stored in the metadata field of the file
document on a successful upload.
An optional MIME type. This field should only be used for backwards
compatibility with older GridFS implementations. New applications should
store the content type in the metadata hash if needed.
If defined, this will be stored in the contentType field of the file
document on a successful upload.
An optional array of aliases. This field should only be used for backwards
compatibility with older GridFS implementations. New applications should
store aliases in the metadata hash if needed.
If defined, this will be stored in the aliases field of the file
document on a successful upload.
$id = $stream->id;
The id of the file created by the stream. It will be stored in the _id
field of the file document on a successful upload. Some upload methods
require specifying an id at upload time. Defaults to a newly-generated
the BSON::OID manpage or BSON codec specific equivalent.
my $fh = $stream->fh;
print $fh, 'test data...';
close $fh
Returns a new file handle tied to this instance of UploadStream that can be
operated on with the built-in functions print, printf, syswrite,
fileno and close.
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.
$stream->abort;
Aborts the upload by deleting any chunks already uploaded to the database
and closing the stream.
$file_doc = $stream->close;
Closes the stream and flushes any remaining data to the database. Once this is
done a file document is created in the GridFS bucket, making the uploaded file
visible in subsequent queries or downloads.
On success, the file document hash reference is returned as a convenience.
Important notes:
-
Calling close will also cause any tied file handles created for the stream to also close.
-
close will be automatically called when a stream object is destroyed. When called this way, any errors thrown will not halt execution.
-
Calling
close repeatedly will warn.
if ( $stream->fileno ) { ... }
Works like the builtin fileno, but it returns -1 if the stream is open
and undef if closed.
$stream->print(@data);
Works like the builtin print.
$stream->printf($format, @data);
Works like the builtin printf.
$stream->syswrite($buffer);
$stream->syswrite($buffer, $length);
$stream->syswrite($buffer, $length, $offset);
Works like the builtin syswrite.
All the writer methods (e.g. print, printf, etc.) send a binary
representation of the string input provided (or generated in the case of
printf). Unless you explicitly encode it to bytes, this will be the
internal representation of the string in the Perl interpreter. If you
have ASCII characters, it will already be bytes. If you have any
characters above 0xff, it will be UTF-8 encoded codepoints. If you have
characters between 0x80 and 0xff and not higher, you might have
either bytes or UTF-8 internally.
You are strongly encouraged to do your own character encoding with
the Encode module or equivalent and upload only bytes to GridFS.
This software is Copyright (c) 2020 by MongoDB, Inc.
This is free software, licensed under:
The Apache License, Version 2.0, January 2004
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