Example of gitlab CI/CD for a create-react-app application on Amazon S3 Bucket.

.gitlab-ci.yml

image: nikolaik/python-nodejs:latest

stages:
  - install
  - test
  - deploy

prodInstall:
  stage: install
  script:
    - npm install --production
  artifacts:
    untracked: true

unitTesting:
  stage: test
  dependencies:
    - prodInstall
  script:
    - npm install
    - npm run build
    - npm test
  artifacts:
    untracked: true

deployingDev:
  stage: deploy
  only:
    - dev
  dependencies:
    - prodInstall
    - unitTesting
  script:
    - pip3 install awscli
    - aws configure set profile bucket-dev
    - aws configure set aws_access_key_id "$DEV_AWS_KEY"
    - aws configure set aws_secret_access_key "$DEV_AWS_SECRET"
    - ((aws s3api create-bucket --acl public-read  --bucket my-app-dev && echo 'Created bucket.') || echo 'Already existing bucket.')
    - aws s3api put-bucket-website --bucket my-app-dev --website-configuration file://website.json
    - aws s3api put-bucket-policy --bucket my-app-dev --policy file://policy-dev.json
    - aws s3 sync ./build/ s3://my-app-dev

deployingProd:
  stage: deploy
  only:
    - master
  dependencies:
    - prodInstall
    - unitTesting
  script:
    - pip3 install awscli
    - aws configure set profile bucket-prod
    - aws configure set aws_access_key_id "$PROD_AWS_KEY"
    - aws configure set aws_secret_access_key "$PROD_AWS_SECRET"
    - ((aws s3api create-bucket --acl public-read  --bucket my-app-prod && echo 'Created bucket.') || echo 'Already existing bucket.')
    - aws s3api put-bucket-website --bucket my-app-prod --website-configuration file://website.json
    - aws s3api put-bucket-policy --bucket my-app-prod --policy file://policy-prod.json
    - aws s3 sync ./build/ s3://my-app-prod

policy-dev.json

{
    "Statement": {
        "Sid": "PublicReadGetObject",
        "Effect": "Allow",
        "Principal": "*",
        "Action": ["s3:GetObject"],
        "Resource": ["arn:aws:s3:::my-app-dev/*"]
    }
}

policy-prod.json

{
    "Statement": {
        "Sid": "PublicReadGetObject",
        "Effect": "Allow",
        "Principal": "*",
        "Action": ["s3:GetObject"],
        "Resource": ["arn:aws:s3:::my-app-prod/*"]
    }
}

website.json

{
    "IndexDocument": {
        "Suffix": "index.html"
    }
}