build spec for aws codebuild

buildspec.yml

version: 0.2
phases:
  install:
    runtime-versions:
      nodejs: 10
    commands:
      - npm install serverless -g
  build:
    commands:
      - npm install
      - |
        if expr "${CLOUDFRONTID}" : "DEFAULT" >/dev/null; then
          serverless; 
          aws s3 sync ./.serverless s3://${YOUR S3 BUCKET}/.serverless;
        else 
          aws s3 sync s3://${YOUR S3 BUCKET}/.serverless ./.serverless;
          serverless;
          aws cloudfront create-invalidation --distribution-id ${CLOUDFRONTID} --paths '/*';
        fi