README.md

PeerPrep Docker Compose Guide

This project uses Docker Compose to manage multiple services such as a frontend, backend, and a database. The configuration is defined in the docker-compose.yml file, and environment variables can be stored in environment files for different environments (e.g., development, production).

More details on how to set up Docker Compose can be found here

Prerequisites

Before you begin, ensure you have the following installed on your machine:

• Docker
• Docker Compose

Project Structure

In the ./apps directory:

.
├── docker-compose.yml       # Docker Compose configuration
├── README.md                # Project documentation (for docker compose)
├── .env                     # Global environment variables (optional)
├── frontend
│   ├── Dockerfile           # Dockerfile for frontend
│   └── ... (other frontend files)
├── matching-service
│   ├── Dockerfile           # Dockerfile for matching-service
│   └── ... (other matching-service files)
├── question-service
│   ├── Dockerfile           # Dockerfile for question-service
│   └── ... (other question-service files)
├── user-service
│   ├── Dockerfile           # Dockerfile for user-service
│   └── ... (other user-service files)
├── execution-service
│   ├── Dockerfile           # Dockerfile for execution-service
│   └── ... (other execution-service files)
├── signalling-service
│   ├── Dockerfile           # Dockerfile for signalling-service
│   └── ... (other signalling-service files)
├── history-service
│   ├── Dockerfile           # Dockerfile for history-service
│   └── ... (other history-service files)

Docker Compose Setup

Ensure that you are currently using Docker Compose v2 in your local Docker Desktop.

• Launch your local Docker Desktop application
• Click on settings button at the top right hand corner (beside the name)
• Under the General tab, scroll down until you see a checkbox that says Use Docker Compose V2, ensure that the box is checked then apply and restart (refer to the image below)

By using multiple Dockerfiles in Docker Compose, we can manage complex multi-container applications where each service has its own environment and build process.

1. Build and Start the Application

To build and run both the frontend and backend services, you can change your directory to the ./apps directory and run:

docker-compose up --build

This will:

• Build the Docker images for all services using the specified Dockerfiles
• Start the containers and map the defined ports

2. Access the Application

Once running, you can access:

• The frontend at http://localhost:3000
• The user-service at http://localhost:3001
• The question-service at http://localhost:8080 (REST) and http://localhost:50051 (gRPC)
• The matching-service at http://localhost:8081
• The history-service at http://localhost:8082
• The execution-service at http://localhost:8083
• The signalling-service at http://localhost:4444
• The redis at http://localhost:6379
• The rabbitmq at http://localhost:5672

3. Stopping Services

To stop the running services, run:

docker-compose down

This command will stop and remove the containers, networks, and volumes created by docker-compose up.

Troubleshooting

Common Issues

• Port Conflicts: If you encounter port conflicts, ensure the host ports specified in docker-compose.yml (e.g., 3000:3000) are not in use by other applications.
• Environment Variables Not Loaded: Ensure the .env files are in the correct directories as found in the docker-compose.yml file.
• Command execution failed: When you try running test cases or submitting the code in the collaborative environment, if you encounter the following error message:

  Command execution failed: Unable to find image 'apps-python-sandbox:latest' locally docker: Error response from daemon: pull access denied for apps-python-sandbox, repository does not exist or may require 'docker login': denied: requested access to the resource is denied. See 'docker run --help'. : exit status 125

  Ensure that you have Docker Compose V2 enabled for your Docker Desktop application. Please refer to the Docker Compose setup guide above to enable it locally.

Known Issues

• Mongo DB Connection Failing: The user service fails to connect to the Mongo DB server on NUS Wi-Fi. To resolve this we have to use another network.

Logs

You can view the logs for each service using the following command:

docker-compose logs

Useful Commands

Rebuild a specific service:

docker-compose build <service_name>

Start services in detached mode (run in the background):

docker-compose up -d

Remove all containers, networks, and volumes created by Docker Compose:

docker-compose down --volumes