处理 navigator.sendBeacon 请求在 rails 中的 CSRF 真实性令牌

Question

$(window).on('unload', function() {
db.flipCounter.get(gon.slug, function(obj) {
var payload = {
slug: gon.slug,
localFlipCount: obj.fc,
time: Date.now()
}
navigator.sendBeacon('/analytics', csrfProtect(payload))
})
})
function csrfProtect(payload) {
var param = $("meta[name=csrf-param]").attr("content")
var token = $("meta[name=csrf-token]").attr("content")
if (param && token) payload[param] = token
return new Blob([JSON.stringify(payload)], { type: "application/x-www-form-urlencoded; charset=utf-8" })
}

在上面的代码中，我希望使用有效负载按 POST 到"/analytics"网址。我收到以下错误(警告)...尝试触发请求：

承诺.js：840 未处理的拒绝： 类型错误： 无法在字符串"{"slug"上创建属性"authenticity_token"："test-page-by-marvin-danig"，"localFlipCount"：1，"time"：1524241435403}'

嗯。

。触发请求，我得到：

Processing by BooksController#analytics as */*
Parameters: {"{"slug":"test-book-by-marvin-danig","localFlipCount":1,"time":1524243279653,"param":"8rzDx/TNL8YeU1/NWgWSk6gB/UvmbB9Ip VajDCgfDUv5Q4pjh7x0GUG1il1jDJajtJyHf84Xv5Pt14fiCnA9w"=>"="}"}
Can't verify CSRF token authenticity.
exception
ActionController::InvalidAuthenticityToken

---

更新：问题仍未解决。这是我现在所处的位置：

我的routes.rb上有以下 GET & POST 路由打开：

# Analytics (flipCounter)
get 'auth_token', to: 'analytics#auth_token'
post 'receptor', to: 'analytics#receptor', as: :receptor  

这些显然映射到analytics_controller，如下所示：

class AnalyticsController < ApplicationController
respond_to :js
def auth_token
session[:_csrf_token] = form_authenticity_token
end
def receptor
logger.debug "Check book slug first: #{params}" 
begin
book = Book.friendly.find(params[:slug])
rescue ActiveRecord::RecordNotFound => e
book = nil
end
if book.exists?
book.flipcount += params[:flipcount].to_i
end
end
private
end 

除了auth_token方法外，我还得到了一个auth_token.json.erb模板，该模板按以下方式提供：

{ "authenticity_token": "<%= session[:_csrf_token] %>" } 

客户端javascript(糟糕的草稿)是这样的：

// When state of book changes to `not_flipping`:
flipCount += 1
const o = { slug: gon.slug, fc: flipCount }
// IndexedDb initiated elsewhere.
db.transaction('rw', db.flipCounter, function(e) {
db.flipCounter.put(o)
}).then(function(e) {
const URL = '/auth_token' // First fetch the authenticity_token!
fetch(URL, {
method: 'GET'
}).then(function(res) {
return res.json()
}).then(function(token) {

return postBookData(token)

}).catch(err => console.log(err))
}).catch(function(e) {
console.log(e)
})

function postBookData(token) {
db.flipCounter.get(gon.slug, function(obj) {
// var payload = new FormData()
// payload.append('slug', gon.slug)
// payload.append('localFlipCount', obj.fc)
// payload.append('authenticity_token', token.authenticity_token)
// payload.append('type', 'application/x-www-form-urlencoded;')
// payload.append('charset=utf-8', 'ok')
//  payload.append('X-CSRF-Token', token.authenticity_token)
//var payload = { 'slug': gon.slug }
let body = {
slug: gon.slug,
flipcount: obj.fc,
time: Date.now()
}
let headers = {
type: 'application/x-www-form-urlencoded; charset=utf-8',
'X-CSRF-Token': token.authenticity_token
}
let blob = new Blob([JSON.stringify(body)], headers);
let url = '/receptor'
navigator.sendBeacon(url, blob);
}).then(function() {
flipCount = 0
var o = { slug: gon.slug, fc: flipCount }
}).catch(err => console.log(err))
}

navigator.sendBeacon触发的请求对象不正确，因为未设置X-CSRF-Token，并且我显然在服务器端收到以下错误：

Started POST "/receptor" for 127.0.0.1 at 2018-04-26 09:00:33 -0400
Processing by AnalyticsController#receptor as */*
Parameters: {"{"slug":"bookiza-documentation-by-marvin-danig","fc":1}"=>nil}
Can't verify CSRF token authenticity.
exception
ActionController::InvalidAuthenticityToken
Rendering public/500.html
Rendered public/500.html (1.0ms)
Completed 500 Internal Server Error in 337ms (Views: 335.8ms | ActiveRecord: 0.0ms)

有没有人使用服务工作者在完全离线的页面上在 Rails 应用程序上实现navigator.sendBeacon场景？

Answer 1

刚刚抓住了这个障碍，我的解决方案的js端如下：

window.addEventListener("unload", function() {
var url = "/your_metrics_path",
data = new FormData(),
token = $('meta[name="csrf-token"]').attr('content');
// add your data
data.append("foo", "bar");
// add the auth token
data.append("authenticity_token", token);
// off she goes
navigator.sendBeacon(url, data);
});

希望这有帮助。

Answer 2

你走在正确的轨道上，我已经成功地做到了这一点，从 DOM 中获取 CSRF 令牌并在 JavaScript 请求中使用它。下面是一个普通 Rails 表单在参数中发送的示例：

Started PATCH "/titles/25104" for 127.0.0.1 at 2018-04-20 14:19:11 -0700
Processing by TitlesController#update as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"N97wNps0PMEBcqEsza8gNV741uPZNmltPgJHeeBNmTF0rc2KCaePBlZeCxId+su1sdAYMsgyd/78u9S/mdmprw==" }

看起来你只需要把事情变成正确的哈希结构，你应该在路上。我认为您需要调整一些键。

Answer 3

我刚刚了解到，在使用 Beacon 请求时，无法自定义请求方法、提供自定义请求标头或更改请求和响应的其他处理属性。在此处查看 W3C 编辑的信标草稿。

请改用提取 API。