ruby 在 rails 调用外部 api 并显示结果

Question

我正在尝试调用 API（点赞 https://jsonplaceholder.typicode.com/）。这个想法很简单，点击按钮显示资源，但我在实现它时遇到了麻烦。我下面的只是调用该函数并想在控制台中打印它的按钮。

错误：

enter code here No route matches [POST] "/dashboard/fetch_action"

路线

resources :dashboard do
 collection do
   get :fetch_action
 end
end

dashboard_controller.er

require 'faraday'

def index
end

def fetch_action
    response = Faraday.get 'https://jsonplaceholder.typicode.com/posts/1'
    puts response
    # return response 
end

index.html.erb

    <%= button_to "fetch action", fetch_action_dashboard_index_path, class: "btn btn-warning" %>

谢谢

编辑：

路线：

Rails.application.routes.draw do

  devise_for :users
  
  devise_scope :user do
    root to: 'devise/sessions#new'
  end

  get 'dashboard' => 'dashboard#index'
  get '/dashboard/fetch-action', to: 'dashboard#fetch_action', as: 'dashboard_fetch_action'
  get '/user' => 'dashboard#index', :as => :user_root

end

耙路

    new_user_session GET    /users/sign_in(.:format)                                                                 devise/sessions#new
             user_session POST   /users/sign_in(.:format)                                                                 devise/sessions#create
     destroy_user_session DELETE /users/sign_out(.:format)                                                                devise/sessions#destroy
        new_user_password GET    /users/password/new(.:format)                                                            devise/passwords#new
       edit_user_password GET    /users/password/edit(.:format)                                                           devise/passwords#edit
            user_password PATCH  /users/password(.:format)                                                                devise/passwords#update
                          PUT    /users/password(.:format)                                                                devise/passwords#update
                          POST   /users/password(.:format)                                                                devise/passwords#create
 cancel_user_registration GET    /users/cancel(.:format)                                                                  devise/registrations#cancel
    new_user_registration GET    /users/sign_up(.:format)                                                                 devise/registrations#new
   edit_user_registration GET    /users/edit(.:format)                                                                    devise/registrations#edit
        user_registration PATCH  /users(.:format)                                                                         devise/registrations#update
                          PUT    /users(.:format)                                                                         devise/registrations#update
                          DELETE /users(.:format)                                                                         devise/registrations#destroy
                          POST   /users(.:format)                                                                         devise/registrations#create
                     root GET    /                                                                                        devise/sessions#new
                dashboard GET    /dashboard(.:format)                                                                     dashboard#index
   dashboard_fetch_action GET    /dashboard/fetch-action(.:format)                                                        dashboard#fetch_action
                user_root GET    /user(.:format)                                                                          dashboard#index
       rails_service_blob GET    /rails/active_storage/blobs/:signed_id/*filename(.:format)                               active_storage/blobs#show
rails_blob_representation GET    /rails/active_storage/representations/:signed_blob_id/:variation_key/*filename(.:format) active_storage/representations#show
       rails_disk_service GET    /rails/active_storage/disk/:encoded_key/*filename(.:format)                              active_storage/disk#show
update_rails_disk_service PUT    /rails/active_storage/disk/:encoded_token(.:format)                                      active_storage/disk#update
     rails_direct_uploads POST   /rails/active_storage/direct_uploads(.:format)                                           active_storage/direct_uploads#create

index.html.eb

<%= link_to "fetch action", dashboard_fetch_action_path, class: "btn btn-info" %>

<%= @response %>

获取-action.html.erb

<%= @response %>

dashboard_controller

def index
end

def show
end

def fetch_action
    uri = URI('https://jsonplaceholder.typicode.com/posts/1')
    req = Net::HTTP.get(uri)
    @response = JSON.parse(req)
end

错误（单击 link_to 重定向到 dashboard/fetch-action 时出现以下错误）：

DashboardController#show is missing a template for this request format and variant. request.formats: ["text/html"] request.variant: [] NOTE! For XHR/Ajax or API requests, this action would normally respond with 204 No Content: an empty white screen. Since you're loading it in a web browser, we assume that you expected to actually render a template, not nothing, so we're showing an error to be extra-clear. If you expect 204 No Content, carry on. That's what you'll get from an XHR or API request. Give it a shot.

Answer 1

故障排除和设置路由

首先，在您的终端中，运行 rake routes 打印您应用中的路线。 Post 输出到这里。但是您需要检查按钮中使用的 fetch_action_dashboard_index_path 命令的输出 - 这是正确的路径吗？

我想不是。还有一种更简单的方法来声明一条路线。您在路由中使用资源声明所做的是为仪表板控制器的索引、显示、创建、更新和删除操作配置路由。 routes.rb 文件中的以下行将仅设置 fetch_action 路由并将其命名为“dashboard_fetch_action”

get '/dashboard/fetch-action', to: 'dashboard#fetch_action', as: 'dashboard_fetch_action'

正在创建通往该路线的 link

第二；使用 link_to 而不是 button_to 来确保您发出 GET 请求。您正在应用的 btn 类将使 link 看起来像一个按钮，并且 a 标签在语义上比 button 更正确（因为您想要 GET）所以使用：

<%= link_to "fetch action", dashboard_fetch_action_path, class: "btn btn-warning" %>

呈现动作的结果

最后确保您在 app/views/dashboard/fetch_action.html.erb 中有一个文件，它将 API 响应呈现为 HTML。此内容（或类似内容）将实现这一目标。

<%= @response =>

并且，在仪表板控制器中的 fetch_action 操作中。使用 @response = Faraday... 而不是 response = Faraday...。这样就可以在视图 HTML 中访问 response 对象（这就是 @ 所表示的）

def fetch_action
    @response = Faraday.get 'https://jsonplaceholder.typicode.com/posts/1'
end

Answer 2

您是否尝试过将模板重命名为 fetch_action.html.erb？

据我所知，Rails希望模板名称与操作名称匹配，这可能是 fetch_action 因为 Ruby 方法不能包含破折号 - .破折号用于减法，这就是它在方法名称中无效的原因。

ruby 在 rails 调用外部 api 并显示结果

ruby on rails call external api and show results

ruby

api

model-view-controller

ruby-on-rails

jsonplaceholder

故障排除和设置路由

正在创建通往该路线的 link

呈现动作的结果