Deployment about webpacker

[johnmaxwell]

Reason dev dependencies get installed is that both rails and your rake task run yarn without the --production flag, which is the flag that skips dev dependencies. Not sure if that is intended or not?

I'm running into this right now. I'm using Vue, which uses the NODE_ENV environment var to determine if it should be run in production mode or not. (When I'm deploying, I want it in production mode.) When I set NODE_ENV to production on the production server and deploy, it will fail to build the pack because webpack, et al are "devDependencies" and not "dependencies" in package.json

What is the intended deployment strategy for webpacker? Based on the way webpacker compilation is tagged onto the assets:precompile rake task, it seems like the idea is that we compile on the webpacker assets on deployment server during deployment -- like the assets pipeline assets. Is that correct?

[jensljungblad]

Also wondering about this commit: 5afa882

If webpack etc are installed as dev dependencies, they won't be installed on, say Heroku. Does that mean you think assets should be built in a dev environment prior to deploying?

[joerodrig]

• Creating a blank yarn.lock file in your root directory tricks Heroku into installing Yarn.

• For compiling your assets before deploying, you can create a rake task. Below is what I've been building off of:

# assets.rake
Rake::Task["assets:precompile"]
  .clear_prerequisites
  .enhance(["assets:compile_environment"])

namespace :assets do
  task compile_environment: [:yarn, :webpack] do
    Rake::Task["assets:environment"].invoke
  end

  desc "Install node deps via yarn"

  task :yarn do
    sh "bundle exec ./bin/yarn"
  end

  task :webpack do
    sh "bundle exec rails webpacker:compile"
  end
end

• I haven't hit any issues deploying to Heroku with webpack listed as a devDependency, but admittedly, I haven't really looked into why!

[jensljungblad]

@joerodrig3 Do you need the nodejs build pack on Heroku as well? I can't get it to work even with an empty yarn.lock file in the root directory.

[joerodrig]

Yep, any app that uses node needs the nodejs buildpack on Heroku: heroku/nodejs

[jensljungblad]

Thanks, got it working with the node build pack. Wonder if it would make sense to add node and yarn to the Heroku ruby build pack? I guess a Rails 5.1 app won't function correctly without it?

I grabbed this from rails master which is similar to what you suggested: https://github.com/rails/rails/blob/f04a49b033e3da54a52f76289863ec87a3c30438/railties/lib/rails/tasks/yarn.rake

Reason dev dependencies get installed is that both rails and your rake task run yarn without the --production flag, which is the flag that skips dev dependencies. Not sure if that is intended or not?

[joerodrig]

In #72 dhh stated:

Heroku can update their Yarn detection in time.

So I am going to assume we'll have to wait and see what Heroku does :) Until then the Yarn hack seems like the only way to go. Custom buildpacks may help too. On a work project we did end up modifying one buildpack to fix a ruby version conflict we were having with Webpacker

[jensljungblad]

Sounds good!