Question

我对Rails世界非常陌生，我想创建一个包裹跟踪应用程序。我希望能够将包裹的跟踪号传递给我创建的用于刮擦承运人站点的rails方法。

我得到了错误数量的参数错误，并且不明白为什么。任何输入表示赞赏！

routes.rb

Rails.application.routes.draw do
  resources :packages do
    match '/scrape', to: 'packages#scrape', via: :post, on: :collection
  end
  root 'home#index'

  get 'dashboard' => 'packages#index'
  get '/logout' => 'auth0#logout'
  get 'auth/auth0', as: 'authentication'
  get 'auth/auth0/callback' => 'auth0#callback'
  get 'auth/failure' => 'auth0#failure'
  # For details on the DSL available within this file, see https://guides.rubyonrails.org/routing.html
end

抓取方法

def scrape(tracking_num)
    require 'watir'
    url = "https://www.ups.com/track?loc=en_US&tracknum=#{tracking_num}&requester=WT/trackdetails"
    b = Watir::Browser.new :chrome, headless: true
    b.goto(url)
    text = b.p(:class, 'ups-txt_size_double_lg').when_present.text
    flash.now[:notice] = text
 end

button_to

<%= button_to 'Track', scrape_packages_path(tracking_num: package.tracking), class: "btn btn-sm btn-outline-dark" %>

Answer 1

POST请求和操作未像您编写的那样使用。我首先回答您的直接问题：调用控制器中的操作时不带参数。 def scrape(tracking_num)期望使用一个参数来调用，因此会引发错误。

以下是修改内容：

Rails.application.routes.draw do
  resources :packages do
    # you can use 'post' directly
    post '/scrape', to: 'packages#scrape', on: :collection
  end
end

  # remove the parameters of method and use params[:tracking_num] to get it
  def scrape
    require 'watir'
    url = "https://www.ups.com/track?loc=en_US&tracknum=#{params[:tracking_num]}&requester=WT/trackdetails"
    b = Watir::Browser.new :chrome, headless: true
    b.goto(url)
    text = b.p(:class, 'ups-txt_size_double_lg').when_present.text
    flash.now[:notice] = text
  end

# add { remote: true, method: :post } to the link
<%= link_to 'Track', scrape_packages_path(tracking_num: package.tracking), class: "btn btn-sm btn-outline-dark", method: :post, remote: true %>

错误的参数数量轨不会将参数传递给方法

1 个答案: