     {Number|dynamic} streams     - Quantity of parallel upload streams, default: 2
     {Number|dynamic} chunkSize   - Chunk size for upload
     {String}      transport      - Upload transport `http` or `ddp`
-    {DDP}         ddp            - Custom DDP connection
+    {Object}      ddp            - Custom DDP connection. Object returned form `DDP.connect()`
     {Function}    onUploaded     - Callback triggered when upload is finished, with two arguments `error` and `fileRef`
     {Function}    onStart        - Callback triggered when upload is started after all successful validations, with two arguments `error` (always null) and `fileRef`
     {Function}    onError        - Callback triggered on error in upload and/or FileReader, with two arguments `error` and `fileData`

        onUploaded:      Match.Optional Function
        onProgress:      Match.Optional Function
        onBeforeUpload:  Match.Optional Function
        allowWebWorkers: Boolean,
        ddp:             Match.Any,
      }

      if not @config.fileName and not @config.file.name

  ###
  find: (selector, options) ->
    console.info "[FilesCollection] [find(#{JSON.stringify(selector)}, #{JSON.stringify(options)})]" if @debug
    check selector, Match.Optional Match.OneOf Object, String, Boolean, Number, null
    check options, Match.Optional Object

    selector = {} unless arguments.length
