Backend Setup

This page documents the backend setup flow for the broader NeuroLab platform. It assumes you are working from the platform source tree rather than this docs repository alone.

The Backend service provides the core API for NeuroLab, managing users, clinical data, billing, and orchestrating analysis sessions. It is built with Node.js and Express.

Prerequisites

Ensure you have the following installed on your system:

• Node.js: v22.0.0 or higher
• MongoDB: v7.0 or higher
• Redis: Required for session management (optional but recommended)

Installation

1. Navigate to the Backend Directory

From the root of the NeuroLab repository:

cd backend

2. Install Dependencies

We recommend using npm ci for a clean installation of exact dependency versions:

npm ci

Configuration

Environment Variables

Create a .env file in the backend/ directory by copying the example:

cp .env.example .env

Core Configuration

| Variable | Description | Default | | :--- | :--- | :--- | | NODE_ENV | Environment mode | development | | PORT | API Port | 5000 | | MONGODB_URI | Connection string for MongoDB | - | | ACCESS_TOKEN_SECRET | Secret for JWT access tokens | - | | REFRESH_TOKEN_SECRET | Secret for JWT refresh tokens | - |

Service Integration

| Variable | Description | Default | | :--- | :--- | :--- | | AI_API_URL | URL of the AI Service | http://localhost:8000 | | AI_MODEL_TYPE | Default model for analysis | original | | FILE_STORAGE_TYPE | Storage type (local or minio) | local |

Running the Service

Development Mode

Start the backend with nodemon for auto-reloading:

npm run dev

Production Mode

Build and run the production server:

npm start

Verification

Once the service is running, you can access the health endpoint:

• URL: http://localhost:5000/

API Documentation

The backend automatically generates Swagger documentation:

• Swagger UI: http://localhost:5000/api-docs

Database Connection

Check the console output to ensure the connection to MongoDB is successful:

✅ Database connected successfully
✅ All services initialized successfully

Troubleshooting

Common Issues

MongoDB Connection Failure Ensure your MONGODB_URI is correct and that the MongoDB service is running locally or accessible over the network.

Port Conflict If port 5000 is already in use, you can change it by updating the PORT variable in your .env file.

Rate Limiting The backend has rate limiting enabled. If you receive 429 Too Many Requests during development, you can increase the limit in server.js or use a different IP.

File Upload Errors If using FILE_STORAGE_TYPE=local, ensure the temp and uploads directories exist and are writable by the Node.js process.