rake webpacker:check_node errors out if no node installed

[tdegrunt]

Version: webpacker 3.0.2
Ruby: 2.4.2

rake webpacker:check_node --trace                                                                                                     ⏎
** Invoke webpacker:check_node (first_time)
** Execute webpacker:check_node
/Users/tdegrunt/.rbenv/versions/2.4.2/bin/rake: No such file or directory - node
rake aborted!
NoMethodError: undefined method `strip' for nil:NilClass
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/webpacker-3.0.2/lib/tasks/webpacker/check_node.rake:16:in `block (2 levels) in <top (required)>'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/task.rb:251:in `block in execute'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/task.rb:251:in `each'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/task.rb:251:in `execute'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/task.rb:195:in `block in invoke_with_call_chain'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/2.4.0/monitor.rb:214:in `mon_synchronize'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/task.rb:188:in `invoke_with_call_chain'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/task.rb:181:in `invoke'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:153:in `invoke_task'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:109:in `block (2 levels) in top_level'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:109:in `each'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:109:in `block in top_level'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:118:in `run_with_threads'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:103:in `top_level'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:81:in `block in run'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:179:in `standard_exception_handling'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/lib/rake/application.rb:78:in `run'
/Users/tdegrunt/.rbenv/versions/2.4.2/lib/ruby/gems/2.4.0/gems/rake-12.1.0/exe/rake:27:in `<top (required)>'
/Users/tdegrunt/.rbenv/versions/2.4.2/bin/rake:23:in `load'
/Users/tdegrunt/.rbenv/versions/2.4.2/bin/rake:23:in `<main>'
Tasks: TOP => webpacker:check_node

If this code in check_node.rake is changed:

      begin
        node_version = `node -v`
      rescue Errno::ENOENT
        node_version = `nodejs -v`
        raise Errno::ENOENT if node_version.blank?
      end

to:

      begin
        node_version = `node -v`
      rescue Errno::ENOENT
        node_version = `nodejs -v`
      end
      raise Errno::ENOENT if node_version.blank?

it seems to behave and report:

rake webpacker:check_node --trace                                                                                                     ⏎
** Invoke webpacker:check_node (first_time)
** Execute webpacker:check_node
/Users/tdegrunt/.rbenv/versions/2.4.2/bin/rake: No such file or directory - node
Node.js not installed. Please download and install Node.js https://nodejs.org/en/download/

I thought one could re-raise in rescue blocks?

[SergiiVdovareize]

I have a related question. Why doesn't the check_node task see node? node is installed using nvm. node -v returns the version. But the task says No such file or directory - node. At the same moment, the check_yarn task sees the yarn version correctly.
It happens only during the deployment using capistrano. If I copy the check_node task to the project and run it, node version is returned correctly

UPD: this helped - koenpunt/capistrano-nvm#25 (comment)

[mxmzb]

I have the same issue when I try to deploy my app with Docker. It fails the deployment with the output above at the precompiling process...

[gauravtiwari]

      begin
        node_version = `node -v`
      rescue Errno::ENOENT
        node_version = `nodejs -v`
        raise Errno::ENOENT if node_version.blank?
      end

This seems to work fine and report as expected. Where is this happening? locally or during deployment.

[brasic]

I can also confirm this is happening when node is not installed. The reason is that when activesupport is loaded this monkeypatch suppresses Errno::ENOENT. Simple reproduction script:

require 'active_support/core_ext/kernel/agnostics'

begin
  node_version = `node -v`
rescue Errno::ENOENT
  node_version = `nodejs -v`
  raise Errno::ENOENT if node_version.blank?
end

puts "node_version is '#{node_version}'" # without AS monkeypatch, we would never reach this line

The fallback for legacy versions of node introduced in #798 doesn't actually work because of this. Since webpacker is always used alongside rails, this task should not assume that backticks behave as they do in vanilla ruby.

Edit: I've opened #1105 to restore the "expected" behavior.