How to make Elastic Beanstalk uses Yarn instead of NPM in Amazon Linux 2

Question

after researching a lot I still cannot make EB use Yarn to install packages. Below are some ways that I did try:

• Install and run yarn via commands and container_commands in ./ebextensions/options.config (I got this error: Unhandled exception during build: Command 01_run_yarn failed in cfn-init.log)

  This is my ./ebextensions/options.config

      option_settings:
        aws:elasticbeanstalk:application:environment:
          NODE_ENV: production
  
      commands:
        01_install_node:
          command: |
            sudo curl --silent --location https://rpm.nodesource.com/setup_12.x | sudo bash -
            sudo yum -y install nodejs
        02_install_yarn:
          test: '[ ! -f /usr/bin/yarn ] && echo "Yarn not found, installing..."'
          command: |
            sudo wget https://dl.yarnpkg.com/rpm/yarn.repo -O /etc/yum.repos.d/yarn.repo
            sudo yum -y install yarn
  
      container_commands:
        01_run_yarn:
          command: |
            yarn --production
  

• Write script to install and run yarn in ./platform/hooks/prebuild/yarn.sh. I followed this article and got permission denied error in eb-engine.log

Answer 1

You can change permission on your local before pushing code:

git update-index --chmod=+x .platform/hooks/prebuild/yarn.sh

git commit -am 'message'