code: function(model, logger) {
      assert(
        model.schema,
        "model not mongoose format. 'schema' property required."
      )
      assert(
        model.schema.paths,
        "model not mongoose format. 'schema.paths' property required."
      )
      assert(
        model.schema.tree,
        "model not mongoose format. 'schema.tree' property required."
      )
  
      let fields = model.schema.paths
      let fieldNames = Object.keys(fields)
  
      assert(
        model.routeOptions,
        "model not mongoose format. 'routeOptions' property required."
      )
  
      for (let i = 0; i < fieldNames.length; i++) {
        let fieldName = fieldNames[i]
        assert(
          fields[fieldName].options,
          "field not mongoose format. 'options' parameter required."
        )
      }
  
      return true
    }
docs: Assert that a given model follows the mongoose model format.
  @param model
  @param logger
  @returns {boolean}