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在Rails中使用API时,nil:NilClass的未定义方法“each”

httparty ruby-on-rails-5 http json ruby-on-rails

T. Cole · 技术社区 · 7 年前

这显然是一个常见错误。然而,我在检查代码时无法解决这个问题。我正在为国会访问ProPublica的API。我的模型、视图和控制器非常简单,在访问谷歌新闻API时,这段代码与我一起工作。

class CongressTracker < ApplicationRecord
  include HTTParty

  def self.response
    #congress = "most recent congress"
    #chamber = "one each for congress and senate"
    #type = "introduced, passed, etc."

    congress_url = "https://api.propublica.org/congress/v1/115/senate/bills/passed.json"

    HTTParty.get(congress_url,
        :headers => {
        "X-API-KEY" => "api-key-here"
        })
  end
end


class Bill < ApplicationRecord
  include HTTParty
end

我的控制器:

class BillsController < ApplicationController
  def index
    @response = CongressTracker.response
  end
end

我的观点:

<% @response["results"].each do |bill| %>
      <p><%= bill["title"]%></p>
      <p><%= bill["summary"]%></p>
  <% end %>

resources :bills

详细错误:

  Rendering bills/index.html.erb within layouts/application
  Rendered bills/index.html.erb within layouts/application (2.0ms)
Completed 500 Internal Server Error in 312ms (ActiveRecord: 0.0ms)

ActionView::Template::Error (undefined method `each' for nil:NilClass):
    1: <% @response["results"].each do |bill| %>
    2:       <p><%= bill["title"]%></p>
    3:       <p><%= bill["summary"]%></p>
    4:   <% end %>

app/views/bills/index.html.erb:1:in `_app_views_bills_index_html_erb__2110131784793159686_70138696839360'

{
   "status":"OK",
   "copyright":"Copyright (c) 2017 Pro Publica Inc. All Rights Reserved.",
   "results":[
      {
         "congress": "115",
         "chamber": "Senate",
         "num_results": "20",
         "offset": "0",
         "bills": [
              {
                 "bill_id": "hr2825-115",
                 "bill_type": "hr",
                 "number": "H.R.2825",
                 "bill_uri": "https://api.propublica.org/congress/v1/115/bills/hr2825.json",
                 "title": "DHS Authorization Act of 2017",
                 "summary": "",
              },

1 回复 | 直到 7 年前

Lasse Sviland 7 年前

你得到 undefined method 'each' for nil:NilClass {"message"=>"Forbidden"} ,因为您的API密钥不正确。

我测试了你的代码,只要你有正确的API密钥,一切都正常工作。

你的观点有一些错误,很可能是因为你还没有结果。

<% @response["results"].each do |result| %>
  <% result["bills"].each do |bill| %>
    <p><%= bill["title"]%></p>
    <p><%= bill["summary"]%></p>
  <% end %>
<% end %>