Backbone.js jQuery file upload with autosave

app.coffee

# This will automatically create or update model

onRender: =>
  [method, url] = if @model.isNew()
    ["POST", mymodels_path()]
  else
    ["PUT", model_path(@model.id)]

  @$(".upload").fileupload(
    dataType: 'json'
    type: method
    url: url
    formData: {"_method": method}
    done: (e, data) =>
      @model.set(id: data.result.id)
      @render()
  )