ENV FILE SETUP

NestJS Backend API for GoGrab Space platform - Architecture, Best Practices, and Common Issues

🔧 Backend API - Environment Setup (REQUIRED!)

Date: November 18, 2025
Issue: Backend was failing with MongoDB errors because .env file was missing!

✅ FIXED - `.env` File Created

I've created a .env file at apis/backend-api/.env with the following configuration:

# MongoDB Connection (REQUIRED)
MONGODB_CONNECTION_STRING=mongodb+srv://username:[email protected]/?retryWrites=true&w=majority
MONGODB_DATABASE=gograb-dev

# JWT Secret (REQUIRED)
JWT_SECRET=your-super-secret-jwt-key-change-this-in-production

# Server Port
PORT=3000

# Node Environment
NODE_ENV=development

# CORS Origins
ALLOWED_ORIGINS=http://localhost:5200,http://localhost:5701,http://localhost:4200,http://localhost:5300

🚨 IMPORTANT - You MUST Update These Values:

1. MongoDB Connection String (REQUIRED):

Get your MongoDB Atlas connection string:

Go to MongoDB Atlas
Click "Connect" on your cluster
Select "Connect your application"
Copy the connection string
Replace username and password with your actual credentials

Example:

MONGODB_CONNECTION_STRING=mongodb+srv://paco:[email protected]/?retryWrites=true&w=majority

OR use local MongoDB:

MONGODB_CONNECTION_STRING=mongodb://localhost:27017/gograb-dev

2. JWT Secret (REQUIRED):

Generate a secure random string:

# Generate a secure JWT secret
node -e "console.log(require('crypto').randomBytes(64).toString('hex'))"

Then update the .env file:

JWT_SECRET=a8f5f167f44f4964e6c998dee827110c03b8c2e9d3a37f78b4a6f7e8c2d9e1f0

🔄 After Updating `.env`:

Restart the backend:

# Press Ctrl+C in the terminal running the backend
yarn serve:backend-api

Check the logs - You should see:

🚀 ═══════════════════════════════════════════════════════
   GoGrab Backend API - READY
   ═══════════════════════════════════════════════════════

📡 Server:     http://localhost:3000/api
🗄️  Database:   gograb-dev
🌍 Environment: development

🔒 CORS Configuration:
   Total Origins: 4
   1. http://localhost:5200
   2. http://localhost:5701
   3. http://localhost:4200
   4. http://localhost:5300

Test it - Try saving something in the frontend

🐛 Why This Was Causing Errors:

No .env file → No MongoDB connection string
Backend couldn't connect to MongoDB → All write operations failed
Frontend showed 500 errors → "Failed to save universe data"

Now that we have a .env file, the backend can connect to MongoDB! ✅

📚 Environment Variables Explained:

Variable	Purpose	Required?
`MONGODB_CONNECTION_STRING`	MongoDB Atlas or local connection	✅ YES
`MONGODB_DATABASE`	Database name	✅ YES
`JWT_SECRET`	Secret for JWT token signing	✅ YES
`PORT`	Backend server port	No (defaults to 3000)
`NODE_ENV`	Environment mode	No (defaults to development)
`ALLOWED_ORIGINS`	CORS allowed origins	No (has defaults)
`OPENAI_API_KEY`	OpenAI API access	No (only if using AI)
`ANTHROPIC_API_KEY`	Anthropic API access	No (only if using AI)

🔒 Security Notes:

✅ .env is gitignored - Your secrets won't be committed
⚠️ Never commit real credentials to Git
⚠️ Use different secrets for production
✅ Railway has its own environment variables - This is just for local

🎯 Quick Setup Checklist:

Create .env file (DONE!)
Update MONGODB_CONNECTION_STRING with your MongoDB Atlas connection
Update JWT_SECRET with a secure random string
Restart backend: yarn serve:backend-api
Verify "MongoDB connected successfully" in logs
Test saving in frontend

Status: ✅ .env file created - Now update the MongoDB connection string!