Class | Mongo::Grid |
In: |
lib/mongo/gridfs/grid.rb
|
Parent: | Object |
DEFAULT_FS_NAME | = | 'fs' |
Initialize a new Grid instance, consisting of a MongoDB database and a filesystem prefix if not using the default.
@core gridfs
@see GridFileSystem
# File lib/mongo/gridfs/grid.rb, line 33 def initialize(db, fs_name=DEFAULT_FS_NAME) raise MongoArgumentError, "db must be a Mongo::DB." unless db.is_a?(Mongo::DB) @db = db @files = @db["#{fs_name}.files"] @chunks = @db["#{fs_name}.chunks"] @fs_name = fs_name # Create indexes only if we're connected to a primary node. connection = @db.connection if (connection.class == Connection && connection.read_primary?) || (connection.class == ReplSetConnection && connection.primary) @chunks.create_index([['files_id', Mongo::ASCENDING], ['n', Mongo::ASCENDING]], :unique => true) end end
Delete a file from the store.
Note that deleting a GridFS file can result in read errors if another process is attempting to read a file while it‘s being deleted. While the odds for this kind of race condition are small, it‘s important to be aware of.
@param [] id
@return [Boolean]
# File lib/mongo/gridfs/grid.rb, line 98 def delete(id) @files.remove({"_id" => id}) @chunks.remove({"files_id" => id}) end
Read a file from the file store.
@param [] id the file‘s unique id.
@return [Mongo::GridIO]
# File lib/mongo/gridfs/grid.rb, line 84 def get(id) opts = {:query => {'_id' => id}}.merge!(default_grid_io_opts) GridIO.new(@files, @chunks, nil, 'r', opts) end
Store a file in the file store. This method is designed only for writing new files; if you need to update a given file, first delete it using Grid#delete.
Note that arbitary metadata attributes can be saved to the file by passing them in as options.
@param [String, read] data a string or io-like object to store.
@option opts [String] :filename (nil) a name for the file. @option opts [Hash] :metadata ({}) any additional data to store with the file. @option opts [ObjectId] :_id (ObjectId) a unique id for
the file to be use in lieu of an automatically generated one.
@option opts [String] :content_type (‘binary/octet-stream’) If no content type is specified,
the content type will may be inferred from the filename extension if the mime-types gem can be loaded. Otherwise, the content type 'binary/octet-stream' will be used.
@option opts [Integer] (262144) :chunk_size size of file chunks in bytes. @option opts [Boolean] :safe (false) When safe mode is enabled, the chunks sent to the server
will be validated using an md5 hash. If validation fails, an exception will be raised.
@return [BSON::ObjectId] the file‘s id.
# File lib/mongo/gridfs/grid.rb, line 69 def put(data, opts={}) opts = opts.dup filename = opts[:filename] opts.merge!(default_grid_io_opts) file = GridIO.new(@files, @chunks, filename, 'w', opts=opts) file.write(data) file.close file.files_id end