Ruby Rails无法在类初始化方法中生成实例变量以生成HttpParty请求

我在通过Ruby类生成签名时遇到问题。当我进入docker容器时，我能够看到initialize方法中的所有实例变量都是nil，除了@api_key变量

我有以下课程

require 'openssl'
require 'base64'

module SeamlessGov
  class Form
    include HTTParty
    attr_accessor :form_id
    base_uri "https://nycopp.seamlessdocs.com/api"

    def initialize()
      @api_key = ENV['SEAMLESS_GOV_API_KEY']
      @signature = generate_signature
      @form_id = ENV['SEAMLESS_GOV_FORM_ID']
      @timestamp = Time.now.to_i.to_s
    end

    def relative_uri
      "/form/#{@form_id}/elements"
    end

    def create_form
      self.class.get(relative_uri, headers: generate_headers)
    end

    private

    def generate_signature
      OpenSSL::HMAC.hexdigest('sha256', ENV['SEAMLESS_GOV_SECRET'], "GET+#{relative_uri}+#{@timestamp}")
      binding.pry
    end

    def generate_headers
      {
        "Authorization"  => "HMAC-SHA256 api_key='#{@api_key}' signature='#{@timestamp}'",
         Net::HTTP::ImmutableHeaderKey.new('AuthDate') => "#{@timestamp}"
      }
    end
  end
end

如您所见，通过generate_签名方法中的binding.pry，我可以看到实例变量：

生成签名所需的相对_uri方法没有在字符串中加载@form_id变量

这是控制器：

class FormsController < ApplicationController
  def display_form
    @form = SeamlessGov::Form.new().create_form
  end
end

如果我调用create_form，这是输出：

{"error"=>true,
 "error_log"=>
  [{"error_code"=>"missing_date_headers",
    "error_message"=>"Request is missing date headers",
    "error_description"=>
     "{\"Host\":\"nycopp.seamlessdocs.com\",\"Connection\":\"close\",\"X-Real-IP\":\"71.249.243.7\",\"X-Forwarded-For\":\"71.249.243.7\",\"X-Forwarded-Host\":\"nycopp.seamlessdocs.com\",\"X-Forwarded-Port\":\"443\",\"X-Forwarded-Proto\":\"https\",\"X-Original-URI\":\"\\/api\\/form\\/\\/elements\",\"X-Scheme\":\"https\",\"Authorization\":\"HMAC-SHA256 api_key='h123xxxxxxxxxx' signature=''\",\"AuthDate\":\"\"}"},
   {"error_code"=>"external_auth_error", "error_message"=>"Date header is missing or timestamp out of bounds"}]}

---

问题是什么？

错误在于操作/计算的顺序

def initialize()
  @api_key = ENV['SEAMLESS_GOV_API_KEY']
  @signature = generate_signature # <= at this point, neither form_id nor timestamp are set. but api key is.
  @form_id = ENV['SEAMLESS_GOV_FORM_ID']
  @timestamp = Time.now.to_i.to_s
end

---

@SergioTulentsev我刚刚用create_form方法的输出更新了帖子。只显示api_键。啊，我现在明白了。在设置其他参数之前生成签名。但是api键已经设置好了，这就是为什么你只能看到它。用文本替换屏幕截图。从来没有一个好的理由将代码作为图像发布。

def initialize()
  @api_key = ENV['SEAMLESS_GOV_API_KEY']
  @signature = generate_signature # <= at this point, neither form_id nor timestamp are set. but api key is.
  @form_id = ENV['SEAMLESS_GOV_FORM_ID']
  @timestamp = Time.now.to_i.to_s
end