webpack not installed

[avegancafe]

Hey there! I just upgraded from webpacker 4.2.2 to 5.0.1 and when running bundle exec rake webpacker:compile I now get the error webpack not installed. I'm not sure what's changed, but I was hoping by using webpacker I did not need to install my own version of webpack, as it is declared as a production dependency of webpacker. Is there any solution to this when using yarn besides additionally adding webpack as a dependency of my application? This seems brittle, as they could easily get out of date with webpacker's internal version of webpack (even though it seems to not be getting installed).

[moubry]

I had this same issue using the Heroku buildpack for Ruby. Webpacker would work locally, but not with the buildpack. I tried adding webpack to my package.json, and that didn’t fix things.

The solution: adding the binstub for bin/yarn fixed the issue for me. It was missing from my project — and apparently the upgrade from Webpacker 4 → 5 required it to be there.

[michaelkoper]

@moubry that fixed it for me, thanks!

In case somebody needs to add this as well. This is the standard bin/yarn from rails new:

#!/usr/bin/env ruby
APP_ROOT = File.expand_path('..', __dir__)
Dir.chdir(APP_ROOT) do
  begin
    exec "yarnpkg", *ARGV
  rescue Errno::ENOENT
    $stderr.puts "Yarn executable was not detected in the system."
    $stderr.puts "Download Yarn at https://yarnpkg.com/en/docs/install"
    exit 1
  end
end

[avegancafe]

Oh yeah sorry I forgot to post my temporary fix! I somehow got this to work by declaring webpack as a dependency of my project, even though it was already in my node modules because of webpacker. Hopefully they don't get out of sync 😂

[guillaumebriday]

Could this issue be closed?

[avegancafe]

I'd put it out there that users of webpacker still should not be required to pin a webpack version in their package.json, but I may be in the minority there haha

[avegancafe]

There are other libraries that do this and every time I encounter an error because of this it's hours of development time lost trying to investigate 😢