webpacker: Heroku error: didn't find any digests file && ActionView::Template::Error (Can't find hello_react)

Step to reproduce:

1. rails new myapp -d postgresql
2. add webpacker to gemfile gem 'webpacker', :git => "https://github.com/rails/webpacker.git"
3. bundle install
4. rails webpacker:install
5. rails webpacker:install:vue
6. rails webpacker:compile
7. use the <%= javascript_pack_tag ‘hello_vue’ %>
8. test on localhost (It works*)
9. heroku create webpacker-demos-123
10. git remote add <heroku-git-url>
11. push to heroku (don’t work*)

ERROR (didn’t find any digests file)

remote: Using webpacker 1.0 from https://github.com/rails/webpacker.git (at master@8f584dd) remote: Bundle complete! 16 Gemfile dependencies, 54 gems now installed. remote: Gems in the groups development and test were not installed. remote: Bundled gems are installed into ./vendor/bundle. remote: Bundle completed (3.32s) remote: Cleaning up the bundler cache. remote: -----> Detecting rake tasks remote: -----> Preparing app for Rails asset pipeline remote: Running: rake assets:precompile remote: I, [2017-02-25T01:31:43.346954 #437] INFO – : Didn’t find any digests file at /tmp/build_a7f573d5e29cf560546c07e2807f75aa/public/packs/digests.json. You must first compile the packs via rails webpacker:compile remote: sh: 1: ./node_modules/webpack/bin/webpack.js: not found remote: ! remote: ! Precompiling assets failed. remote: ! remote: ! Push rejected, failed to compile Ruby app. remote: remote: ! Push failed remote: Verifying deploy… remote: remote: ! Push rejected to webpacker-demos. remote: To https://git.heroku.com/webpacker-demos.git ! [remote rejected] master -> master (pre-receive hook declined) error: failed to push some refs to ‘https://git.heroku.com/webpacker-demos.git’ pushing to origin/master

To fix the above error, turns out I need to rake assets:precompile instead of rails webpacker:compile. Should the error message be modified?

Once the assets are precompiled. Pushing to heroku works but leads to another error ( ActionView::Template::Error (Can’t find hello_react))

2017-02-25T01:41:14.753037+00:00 heroku[router]: at=info method=GET path=“/” host=webpacker-demos.herokuapp.com request_id=44e6cff5-5bbc-46d9-b84c-ced9704e12c3 fwd=“138.75.142.195” dyno=web.1 connect=0ms service=35ms status=500 bytes=1669 2017-02-25T01:41:14.730223+00:00 app[web.1]: I, [2017-02-25T01:41:14.730082 #4] INFO – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] Started GET “/” for 138.75.142.195 at 2017-02-25 01:41:14 +0000 2017-02-25T01:41:14.734543+00:00 app[web.1]: I, [2017-02-25T01:41:14.734419 #4] INFO – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] Processing by FrontpagesController#index as HTML 2017-02-25T01:41:14.750165+00:00 app[web.1]: I, [2017-02-25T01:41:14.750028 #4] INFO – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] Rendering frontpages/index.html.erb within layouts/application 2017-02-25T01:41:14.752474+00:00 app[web.1]: I, [2017-02-25T01:41:14.752379 #4] INFO – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] Rendered frontpages/index.html.erb within layouts/application (2.1ms) 2017-02-25T01:41:14.752779+00:00 app[web.1]: I, [2017-02-25T01:41:14.752711 #4] INFO – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] Completed 500 Internal Server Error in 18ms 2017-02-25T01:41:14.754036+00:00 app[web.1]: F, [2017-02-25T01:41:14.753928 #4] FATAL – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3]
2017-02-25T01:41:14.754105+00:00 app[web.1]: F, [2017-02-25T01:41:14.754040 #4] FATAL – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] ActionView::Template::Error (Can’t find hello_react-e57d9d18a79d866e81fe in #<Webpacker::Digests:0x007f46977f3110 @path=#Pathname:/app/public/packs/digests.json, @digests={}>): 2017-02-25T01:41:14.754371+00:00 app[web.1]: F, [2017-02-25T01:41:14.754297 #4] FATAL – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] 1: <\h1>Hello world! 2017-02-25T01:41:14.754373+00:00 app[web.1]: [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] 2: 2017-02-25T01:41:14.754375+00:00 app[web.1]: [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] 3: <%# javascript_pack_tag ‘hello_vue-819142dc19b77ca48015’ %> 2017-02-25T01:41:14.754376+00:00 app[web.1]: [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] 4: <%= javascript_pack_tag ‘hello_react-e57d9d18a79d866e81fe’ %> 2017-02-25T01:41:14.754426+00:00 app[web.1]: F, [2017-02-25T01:41:14.754370 #4] FATAL – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3]
2017-02-25T01:41:14.754492+00:00 app[web.1]: F, [2017-02-25T01:41:14.754436 #4] FATAL – : [44e6cff5-5bbc-46d9-b84c-ced9704e12c3] app/views/frontpages/index.html.erb:4:in `_app_views_frontpages_index_html_erb___4234948065689000601_69970601556860’

Is this related to existing issues? I’m still digging