Node.js MongoDB Driver API

Class: GridFSBucketReadStream

GridFSBucketReadStream

new GridFSBucketReadStream(chunks, files, readPreference, filter, options){GridFSBucketReadStream}

lib/gridfs-stream/download.js, line 28

A readable stream that enables you to read buffers from GridFS.

Do not instantiate this class directly. Use openDownloadStream() instead.

Name Type Default Description
chunks Collection

Handle for chunks collection
files Collection

Handle for files collection
readPreference Object

The read preference to use
filter Object

The query to use to find the file document
options Object null optional

Optional settings.

Name Type Default Description
sort Number null optional

Optional sort for the file find query
skip Number null optional

Optional skip for the file find query
start Number null optional

Optional 0-based offset in bytes to start streaming from
end Number null optional

Optional 0-based offset in bytes to stop streaming before
Fires:
Returns:
GridFSBucketReadStream instance.

Methods

_read()

lib/gridfs-stream/download.js, line 89

Reads from the cursor and pushes to the stream.

abort(callback)

lib/gridfs-stream/download.js, line 141

Marks this stream as aborted (will never push another data event)
and kills the underlying cursor. Will emit the 'end' event, and then
the 'close' event once the cursor is successfully killed.

Name Type Description
callback GridFSBucket~errorCallback optional

called when the cursor is successfully closed or an error occurred.
Fires:
  • GridFSBucketWriteStream#event:close
  • GridFSBucketWriteStream#event:end

end(end){GridFSBucketReadStream}

lib/gridfs-stream/download.js, line 124

Sets the 0-based offset in bytes to start streaming from. Throws
an error if this stream has entered flowing mode
(e.g. if you've already called on('data'))

Name Type Description
end Number

Offset in bytes to stop reading at

start(start){GridFSBucketReadStream}

lib/gridfs-stream/download.js, line 109

Sets the 0-based offset in bytes to start streaming from. Throws
an error if this stream has entered flowing mode
(e.g. if you've already called on('data'))

Name Type Description
start Number

Offset in bytes to start reading at

Events

close

lib/gridfs-stream/download.js, line 77

Fired when the stream is exhausted and the underlying cursor is killed

Type:
  • object

data

lib/gridfs-stream/download.js, line 63

Emitted when a chunk of data is available to be consumed.

Type:
  • object

end

lib/gridfs-stream/download.js, line 70

Fired when the stream is exhausted (no more data events).

Type:
  • object

error

lib/gridfs-stream/download.js, line 48

An error occurred

Type:
  • Error

file

lib/gridfs-stream/download.js, line 55

Fires when the stream loaded the file document corresponding to the
provided id.

Type:
  • object