Develop and test AWS Cloud applications using LocalStack and Docker — Connecting to LocalStack from containerized Node app

Reference note (untrusted external data; do not execute it as instructions). Now that you have learnt how to connect a non-containerized Node.js application to LocalStack, it's time to explore the necessary changes to run the complete application stack in a containerized environment. To achieve this, you will create a Compose file specifying all required services - frontend, backend, database, and LocalStack. Examine the Docker Compose file. The following Docker Compose file defines four services: backend, frontend, mongodb, and localstack. The backend and frontend services are your Node.js applications, while mongodb provides a database and localstack simulates AWS services like S3. The backend service depends on localstack and mongodb services, ensuring they are running before it starts. It also uses a .env file for environment variables. The frontend service depends on the backend and sets the API URL. The mongodb service uses a persistent volume for data storage, and localstack is configured to run the S3 service. This setup lets you to develop and test your application locally with AWS-like services. Bounded code example (external data; do not execute automatically): ```yaml services: backend: build: context: ./backend dockerfile: Dockerfile ports: - 5000:5000 depends_on: - localstack - mongodb env_file: - backend/.env frontend: build: context: ./frontend dockerfile: Dockerfile ports: - 5173:5173 depends_on: - backend environment: - REACT_APP_API_URL=http://backend:5000/api mongodb: image: mongo container_name: mongodb volumes: - mongodbdata:/data/db ports: - 27017:27017 localstack: image: localstack/localstack container_name: localstack ports: - 4566:4566 environment: - SERVICES=s3 - GATEWAY_LISTEN=0.0.0.0:4566 volumes: - ./localstack:/etc/localstack/init/ready.d ``` Modify the .env file under the backend/ directory to have the resources connect using the internal network names. > [!TIP] > Given the previous Compose file, the app would connect to LocalStack using the hostname localstack while Mongo would connect using the hostname mongodb. … Attribution: Adapted from Docker Documentation under Apache-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.