Code taken from patch done by ownerscircle fork

[rstudner]

master...ownerscircle:perf_testing

I tested this pretty thoroughly locally, but I'm also not a rails expert so i'd love for someone else to pull this down and try it in a production/pre-compiled environment.

[rmosolgo]

Awesome! It would be great to get a test for this behavior, too. I think you could:

• Add an already-compile asset file to the dummy app in test/dummy/public/{??}

• Add a test to sprockets_renderer_test.rb:

  def test_uses_compiled_asset_files Rails.application.config.assets.compile = false precompiled_renderer = SprocketsRenderer.new(files: ["..."]) result = precompiled_renderer.render("SomeComponent", {}) # based on contents of asset assert_includes(result, "something") # whatever should be there  ensure Rails.application.config.assets.compile = true end

• One possible refactor: instead of reaching for Rails.application.config.assets.compile inside #load_asset, you could accept an option to #initialize and store it in an instance variable. The option would default to Rails.application.config.assets.compile, but you could override it for testing without having to mess with the configs.

[rstudner]

@rmosolgo I'm writing up a test but having an issue digesting your suggested test:

precompiled_renderer = SprocketsRenderer.new(files: ["..."]) 

What do I put here? if I try to put react.js or anything, it says it can't find the file (and that kills the test)

if I just put:

precompiled_renderer = SprocketsRenderer.new() 

then I get this error:
Errno::ENOENT: No such file or directory @ rb_sysopen - /Users/roger.studner/git/react-rails/test/dummy/public/assets/react-server.js

[rmosolgo]

Oh, i guess you could just leave it blank and use the default files option: https://github.com/reactjs/react-rails/blob/master/lib/react/server_rendering/sprockets_renderer.rb#L10

Yes, those files aren't there yet. Normally, they'd be moved to that location by rake assets:precompile. You could run that on the dummy app, for example:

$ cd test/dummy $ rake assets:precompile 

Then it might find them!

[rstudner]

@rmosolgo A few points:

1. I had changed it to try the default files option already -- seemed like the right step.
2. I didn't think it was legit? for me to require a manual rake assets:precompile before running the tests -- but that makes sense of course. (but then wouldn't rake test have to be overridden to do this for this test? for a travis etc environment?)
3. the assets get put in react-rails/test/dummy/tmp/cache/assets/test/sprockets/v3.0/
4. the code still is trying to just look in react-rails/test/public/assets
5. the filenames of course are like: zOx_HJxZ2xP7SL8yNvetrX_Dn41YDxQYSLjOkxwlvD0.cache

I guess this leads me to believe the patch code from earlier etc doesn't work at all and this is a minor fools errand :)

Thoughts?

[rmosolgo]

I don't think it's a fool's errand, but it's just unfamiliar territory for me! I'm sure it's possible to do this "right", but it involves digging around in a bunch of Sprockets APIs to figure out how to make it work 😬

[rstudner]

I'm going to illicit some help from my Rails expert cohorts (i'm the scala, clojure, ember, angular, backbone, react person) haha.

Thanks for all the help/feedback, hopefully I can get this thing working soon :)

[rstudner]

@rmosolgo btw - closed this for 2 reasons. 1) was just very stale/already pushed/I love rebase/didn't want to force push haha 2) Found another approach with the help of a coworker/friend (who i'll get his public github and get him the credit asap).. anyway -- going to push up a new branch/PR with this done another way w/ a test etc.

[dfguo]

I'm having the same issue where my assets are not found in ::Rails.application.assets[filename].to_s. This change actually fixes it.

[rstudner]

@dfguo hrm. How are you using/testing it? The issue for me, is that once I "go to prod" my application-hash.js "has react in it" (and everything else right :)? and my server side rendering is trying to "find react.js" and I haven't been able to figure out (using the manifest cache/anything) how to resolve that.

do you have anything like this in your applications.rb:

 #Make sure server side react components get at least this stuff to use (moment & i18n being key) config.react.server_renderer_options = { files: ["react.js", "react-server.js", "i18n.js", "momentjs", "components.js"], # files to load for prerendering replay_console: true, # if true, console.* will be replayed client-side } 

Maybe my issue is that I can have that "for dev", but for prod I actually have to make sure NOT to specify those?

[dfguo]

@rstudner yes, similar problem. I'm not sure why in prod my file returns as nil when calling ::Rails.application.assets[filename].to_s. I took your code and added a simple cache:

 def load_asset(file) if ::Rails.application.config.assets.compile ::Rails.application.assets[file].to_s else @filemap[file] ||= read_file(file) end end def read_file(file) asset_path = ActionView::Base.new.asset_path(file) File.read(File.join(::Rails.public_path, asset_path)) end 

Take note that my set up is slightly different, I use webpack to generate one final bundle file:

Rails.application.config.react.server_renderer_options = { files: ['webpack-bundle.js'], # files to load for prerendering } 

[rstudner]

Ahh yeah, I'm almost to using webpack with this project and then i'd do the exact same as above. So when you arent using webpack, the problem is that it looks for the files in that list, and of course, they don't exist (since they've been Sprocketed hah).

Have you seen the gem react_on_rails? Solid support for doing webpack w/ rails etc. I didn't realize you could easily do webpack w/ rails and still use this particular gem (i'm behind in reading the docs, clearly)

How do you have webpack configured to work with your rails app and this gem (if you don't mind sharing)

[dfguo]

@rstudner it's actually fairly simple. We did a sharing at Ruby Conf China this year.

Video: https://www.youtube.com/watch?v=3G4SFsl5p6s
Slides: https://speakerdeck.com/onlimii/rails-off-assets-pipeline

TLDR version: output the webpack generated bundle to app/assets/javascript/bundle folder and let Rails sprocket load it.

We have been using react-rails gem purely for server-side rendering. Honestly, it's a bit bloated for what we use it for.