NODE_OPTIONS compilation warning after upgrading to 7.x

[robotfelix]

After upgrading shakapacker from 6.6.0 to 7.2.3, I'm now getting warnings about conflicting values of NODE_OPTIONS

WARNING in DefinePlugin
Conflicting values for 'process.env.NODE_OPTIONS'

I've tested and found:

• NODE_OPTIONS="--trace-warnings" in .env and calling ./bin/shakapacker-dev-server => warning
• No NODE_OPTIONS in .env and calling ./bin/shakapacker-dev-server => no warning
• NODE_OPTIONS="--trace-warnings" in .env and calling NODE_OPTIONS="--trace-warnings" ./bin/shakapacker-dev-server => no warning

So I think the changes made in #350 are conflicting with the NODE_OPTIONS configuration I have in a dotenv / .env file and setting the value of NODE_OPTIONS before the .env file is be read.

Ideally I wouldn't have to stop using the .env for configuring this value as it varies between projects.

Has anyone else encountered a similar problem and has a suggestion of how to fix it?

[tomdracz]

How are you passing the values from .env file to your app?

Are you able to provide your webpack config? Can investigate further if we have a reproduction case

[robotfelix]

We have the dotenv-webpack as a dependency in our package.json, as well as dotenv-rails in our Gemfile.

I think the relevant bits of our webpack config are these:

// my-config.js
const webpack = require('webpack');
const Dotenv = require('dotenv-webpack');
// ...
const {generateWebpackConfig, inliningCss} = require('shakapacker');
const ReactRefreshWebpackPlugin = require('@pmmmwh/react-refresh-webpack-plugin');

module.exports = {
  // ...
  plugins: [
    // ...
    new Dotenv(),
    // ...
  ].filter(Boolean),
  // ...
};

// webpack.config.js
const {generateWebpackConfig, merge} = require('shakapacker')
const myConfig = require('./my-config')
const webpackConfig = generateWebpackConfig()

module.exports = merge(webpackConfig, myConfig)

I think Shakapacker::DevServerRunner will initialise NODE_OPTIONS to an empty string before the JS code does anything with the ENV though.

[Judahmeek]

The cause of the error is likely that the Dotenv plugin calls DefinePlugin & so does the EnvironmentPlugin in Shakapacker's default webpack configuration.

The easiest solution is to overwrite the plugins property, instead of merging.