mongo_grid_exts.rb

# wrapping the new GridFileSystem so it has some of the nice helpers of the old GridFS class
# HACK: I set MongoMapper.database to the database I need for the particular call, so I can 
# get away with simpler method calls....
module Mongo
  class GridFSExt
    def self.read(file_loc)
      @gridfs = GridFileSystem.new(MongoMapper.database)
      @gridfs.open(file_loc, "r") {|f| f.read } rescue nil
    end
    
    def self.exist?(file_loc)
      @gridfs = GridFileSystem.new(MongoMapper.database)
      val = @gridfs.open(file_loc, "r") rescue nil
      !val.nil?
    end
    
    def self.list(root_collection=Mongo::Grid::DEFAULT_FS_NAME)
      # @gridfs = GridFileSystem.new(MongoMapper.database)
      MongoMapper.database.collection("#{root_collection}.files").find().map do |f|
        f['filename']
      end      
    end
    
    def self.delete(*names)
      @gridfs = GridFileSystem.new(MongoMapper.database)
      names.each do |name|
        @gridfs.delete(name)
      end
    end      
    
    def self.method_missing(method, *args, &block)
      @gridfs = GridFileSystem.new(MongoMapper.database)
      if @gridfs.respond_to?(method)
        @gridfs.__send__(method, *args, &block)
      else
        super
      end
    end
    
  end
  
  class GridIO
    alias_method :<<, :write
    public :get_md5
    alias_method :md5, :get_md5
  end
end