code: func (c *Context) GetQueryArray(key string) ([]string, bool) {
  	if values, ok := c.Request.URL.Query()[key]; ok && len(values) > 0 {
  		return values, true
  	}
  	return []string{}, false
  }
docs: // GetQueryArray returns a slice of strings for a given query key, plus
  // a boolean value whether at least one value exists for the given key.