Heroku: can't find executable webpack for gem webpacker (Gem::Exception)

[jonhue]

After upgrading to the master branch of this repository, I get the following error when compiling on Heroku:

       Compiling…
       Compilation failed:
       /tmp/build_d4da645e5840bc32169cdef3aecaed44/jonhue-jonhue-97c0597/vendor/bundle/ruby/2.3.0/gems/bundler-1.15.2/lib/bundler/rubygems_integration.rb:432:in `block in replace_bin_path': can't find executable webpack for gem webpacker (Gem::Exception)
       from /tmp/build_d4da645e5840bc32169cdef3aecaed44/jonhue-jonhue-97c0597/vendor/bundle/ruby/2.3.0/gems/bundler-1.15.2/lib/bundler/rubygems_integration.rb:463:in `block in replace_bin_path'
       from ./bin/webpack:29:in `<main>'
 !
 !     Precompiling assets failed.

[Jehops]

We are also seeing this without Heroku:

rails assets:precompile
...
/usr/local/lib/ruby/gems/2.4/gems/bundler-1.16.1/lib/bundler/rubygems_integration.rb:458:in `block in replace_bin_path': can't find executable webpack for gem webpacker (Gem::Exception)
        from /usr/local/lib/ruby/gems/2.4/gems/bundler-1.16.1/lib/bundler/rubygems_integration.rb:489:in `block in replace_bin_path'
        from ./bin/webpack:17:in `<main>'

I notice the FreeBSD package, rubygem-webpacker-rails5 starting with version 3.3.0 no longer installs bin/webpacker and bin/bin/webpack-dev-server under $PREFIX.

[gauravtiwari]

Please run bundle exec rails webpacker:binstubs and commit binstubs to heroku.

[0xifis]

I had the same issue as well when upgrading to webpacker 3.3.0. You need regenerate the binstubs for webpacker (and webpack-dev-server if you are using hot reloading in development).

[Jehops]

Thanks. Could you elaborate on what command need to be run to fix our rubygem-webpacker-rails5 package on FreeBSD (no Heroku)? I assume we need to run something to generate those two executable scripts that are now missing.

[jonhue]

@gauravtiwari I did re-generate the binstubs using the :install generator. Your solution worked though. Any chance, they're not generating the same files?

[Jehops]

Sorry, I somehow missed bundle exec rails webpacker:binstubs. I will try that.

[0xifis]

@jonhue :install may overwrite any custom config you might have previously added to your webpack config files but the binstubs generated are the same as far as I know.

[jonhue]

Of course, I did not override the config files 😉

[Jehops]

Is it possible to generate the scripts without bundler? Bundler is not listed as a production dependency.

[0xifis]

You could generate the binstubs in development and commit it to your repo before deploying.

[Jehops]

This is for an OS package. Running bundler during the package build causes problems. Assuming the old behaviour of installing these scripts under $PREFIX/bin cannot be restored, is there a solution without bundler? What about simply creating links from ${PREFIX}/lib/ruby/gems/2.4/gems/webpacker-3.3.0/lib/install/bin/webpack to ${PREFIX}/bin ?

[Jehops]

When I say creating links, I mean we would do this when building our package. Do you foresee any problems doing this?

[Jehops]

Sorry for the noise. Basically what was suggested above works. We just have to run rails webpacker:binstubs in all packages that require webpacker. Thanks. :)