Question

Rails应用程序经常使用AJAX来呈现动态的javascript视图。例如。 update.js.erb。视图的内容是简单的jQuery，用于交换页面元素和内联呈现的部分。

问题是部分渲染似乎比通过js请求时要长10倍。当在HTML格式的应用程序中的其他地方使用时，它们的呈现速度与预期一样快。

在用卷曲测试时，我终于找到了什么＆＃34;导致＆＃34;放缓。或者更确切地说，添加＆＃34; .js＆＃34;到URL的末尾修复了减速 - 部分以JS格式渲染，就像在HTML格式中一样快。为什么？无论哪种方式，请求和响应都是一样的; Rails正在渲染JS。只有URL中的.js会产生神秘的差异。

Accept: text/javascript标头没有任何区别，也没有任何其他标头浏览器发送。为什么Javascript请求上没有.js会让它变得如此之慢？没有.js URL / Accept标题做同样的事情;告诉Rails格式。为什么Rails会做一些与众不同的事情呢？

我们使用不会生成.js的网址生成器，而我不想手动将format: :js添加到所有网站。{我已经敲了几天头，所以任何帮助都会非常感激！

我做了一个简单的复制，没有数据库查询只是简单的视图：https://github.com/sfcgeorge/url-format-speed

日志的相关部分：

curl 'http://localhost:3000/test_nested' -H 'Accept: */*;q=0.5, text/javascript, application/javascript, application/ecmascript, application/x-ecmascript'

Started GET "/test_nested" for 127.0.0.1 at 2017-09-01 16:38:23 +0100
Processing by TestsController#test_nested as JS
  Rendering tests/test_nested.js.erb
  Rendered tests/_partial.html.erb (0.3ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.1ms)
  Rendered tests/_partial.html.erb (0.8ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.1ms)
  Rendered tests/_partial.html.erb (0.1ms)
  Rendered tests/test_nested.js.erb (129.4ms)
Completed 200 OK in 160ms (Views: 145.3ms)

^看看它有多缓慢？

curl 'http://localhost:3000/test_nested.js' -H 'Accept: */*;q=0.5, text/javascript, application/javascript, application/ecmascript, application/x-ecmascript'

Started GET "/test_nested.js" for 127.0.0.1 at 2017-09-01 16:39:11 +0100
Processing by TestsController#test_nested as JS
  Rendering tests/test_nested.js.erb
  Rendered tests/_partial.html.erb (0.3ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.0ms)
  Rendered tests/_partial.html.erb (0.1ms)
  Rendered tests/test_nested.js.erb (17.2ms)
Completed 200 OK in 24ms (Views: 22.0ms)

我向Rails提出了一个问题，因为在找到最小的复制后，我怀疑它是一个错误。 https://github.com/rails/rails/issues/30502

为什么添加.js会使Rails渲染速度提高10倍？

0 个答案: