code: function validateMethod (method) {
    if (!method) {
      return option.some('HTTP method is not specified')
    }
    if (typeof method !== 'string') {
      return option.some('HTTP method should be type of string')
    }
    if (supportedMethods.indexOf(method.toUpperCase()) < 0) {
      return option.some(`Http method ${method} is not supported`)
    }
    return option.none
  }
docs: Validate HTTP method
  @param {String} method – HTTP method
  @return {String} error