如何使用fetch()将自定义错误通过rails后端传递到JavaScript前端

class CustomError < StandardError
  attr_reader :code, :message

  def initialize(code, message)
    @code = code
    @message = message
  end
end

def some_action
  # ...
  raise CustomError.new(500, "Something went wrong.")
  # ...
end

class SomeController < ApplicationController
  rescue_from CustomError, with: :handle_custom_error

  def some_action
    # ...
    raise CustomError.new(500, "Something went wrong.")
    # ...
  end

  private

  def handle_custom_error(error)
    render json: { error: { code: error.code, message: error.message } }, status: :internal_server_error
  end
end

fetch('/some_endpoint')
  .then(response => {
    if (!response.ok) {
      throw new Error(response.statusText);
    }
    return response.json();
  })
  .then(data => {
    // 处理成功返回的数据
  })
  .catch(error => {
    // 处理错误信息
    console.error(error);
  });