code: function transformConstraintViolationMessages (input) {
      return {
          validationErrors: _.chain(input.details)
      .mapKeys(function(v, k) {
  	  // Use '.' as the key if the entire object is erroneous
        return (input.details.length == 1 && input.details[0].path === 'value' && input.details[0].type === 'object.base') ? '.' : v.path
      })
      .mapValues(function (v) {
              return {
          attributes: _.chain(v.context)
          .pickBy(function(v, k) {
            return typeof v !== 'undefined' && v !== null && k !== 'key'
          })
          .mapValues(function(i) {
            return i.toString()
          }),
          constraintClassName: v.type,
          invalidValue: v.context.value,
                  messageTemplate: v.type,
              }
          })
      }
  }
docs: Converts the error object provided into the specified validation constraint violation error message format.