Different builds based on targeting client vs server code - node.js

Question

I currently have 2 separate webpack builds for server rendered vs client rendered code. Is there an easy way to change the build output based on server/client build?
For example something like this:
// Have some code like this
if(is_client){
console.log('x.y.z')
} else {
server.log('x.y.z')
}
// Webpack outputs:
// replaced code in client.js
console.log('x.y.z')
// replaced code in server.js
server.log('x.y.z')

Answer 1

Have you tried anything like this?
// webpack.config.js
module.exports = () => ['web', 'node'].map(target => {
const config = {
target,
context: path.resolve('__dirname', 'src'),
entry: {
[target]: ['./application.js'],
},
output: {
path: path.resolve(__dirname, 'dist', target),
filename: '[name].js'
},
modules: { rules: ... },
plugins: [
new webpack.DefinePlugin({
IS_NODE: JSON.stringify(target === 'node'),
IS_WEB: JSON.stringify(target === 'web'),
}),
],
};
return config;
});
// later in your code
import logger from 'logger';
if (IS_NODE) {
logger.log('this is node js');
}
if (IS_WEB) {
console.log('this is web');
}
how the compilation works?
// client.bundle.js
import logger from 'logger';
// DefinePlugin creates a constant expression which causes the code below to be unreachable
if (false) {
logger.log('this is node js');
}
if (true) {
console.log('this is web');
}
Finally you will produce your build in production mode, so webpack will include a plugin called UglifyJS, this has a feature called dead code removal (aka tree shaking), so it will delete any unused/unreachable code.
and the final result will look like:
// node.bundle.js
import logger from 'logger';
console.log('this is node js');
//web.bundle.js
console.log('this is node js');