Elastic Beanstalk Nginx Serve Static Files

This is a known bug, They only support python when it comes to the web console. if your application is in nodejs you would need to set these properties from the cli.

you can setup the values from cli this way

aws elasticbeanstalk update-environment --environment-id your_enviornment_id --option-settings 'Namespace=aws:elasticbeanstalk:container:nodejs:staticfiles,OptionName=/assets,Value=/static/assets'

or editing the config file from eb config.

Kashif Zaidi's answer works well, but if you want to keep the setting consistent across multiple deployments, you can make a .ebextensions directory at the project root with some file like 01_environment_settings.config that specifies that setting like so:

option_settings:
  aws:elasticbeanstalk:container:nodejs:staticfiles:
    "/assets": "/static/assets"

You can specify multiple static file settings, for example:

option_settings:
  aws:elasticbeanstalk:container:nodejs:staticfiles:
    "/app/": "frontend_build/"
    "/static/": "frontend_build/static/"
    "/backend_static": "static/"