Couldn't find preset "es2015" relative to directory "web/static/js"

Question

I'm trying to build a vagrant server for dabbling with elixir and phoenix, but after installing all requirements and dependencies, and on running mix phoenix.server I'm getting the following error:

error: Compiling of 'web/static/js/app.js' failed. Couldn't find preset "es2015" relative to directory "web/static/js" ;

I'm not sure of the context of 'preset' here, I'm hoping a more seasoned phoenix user will know what it's getting at.

Some cursory Google's gave me nothing, other than it might be something to do with babel.

Edit: I just tried installing what I assume to be the missing package, sudo npm install babel-preset-es2015 -g, but it hasn't resolved the error.

Answer 1

Please see the fix here: https://github.com/phoenixframework/phoenix/issues/1410

1. Upgrade to node >= v5.0.0
2. npm cache clean
3. cd my_app
4. rm -rf node_modules/
5. npm install
6. mix phoenix.server

Answer 2

I see that there is already an accepted answer here. I just encountered the exact same error, and tried the solution Chris posted above. It did not work for me, but based on the github issue link Chris posted above, I found a solution that worked for me.

I found that you don't necessarily need to be using node v5.0+. I am using node 4.4.3 LTS, and things are working.

npm install --save-dev babel-preset-es2015

Answer 3

My solution which is great works:

.pipe(babel({
    presets: [require('babel-preset-es2015')]
}))

Thanks!