# PM2 Configuration

This document explains how to use PM2 for managing Deathwatch Roller in production.

## What is PM2?

PM2 is a production process manager for Node.js that keeps your application running 24/7.

## Installation

```bash
# Install PM2 globally
npm install -g pm2

# Initialize PM2 ecosystem file
pm2 init
```

## Application Configuration

Create `ecosystem.config.js`:

```javascript
module.exports = {
  apps: [
    {
      name: 'dwroller-frontend',
      cwd: './frontend',
      script: 'npm',
      args: 'start',
      env: {
        NODE_ENV: 'production',
        PORT: 3000
      },
      env_development: {
        NODE_ENV: 'development'
      },
      instances: 1,
      autorestart: true,
      max_memory_restart: '500M'
    },
    {
      name: 'dwroller-backend',
      cwd: './backend',
      script: 'npm',
      args: 'start',
      env: {
        NODE_ENV: 'production',
        PORT: 5000
      },
      env_development: {
        NODE_ENV: 'development'
      },
      instances: 1,
      autorestart: true,
      max_memory_restart: '500M'
    }
  ]
};
```

## Starting the Application

```bash
# Start both apps
pm2 start ecosystem.config.js

# Start only backend
pm2 start ecosystem.config.js --only backend

# Start only frontend
pm2 start ecosystem.config.js --only frontend
```

## Managing Apps

```bash
# View status
pm2 list

# View logs
pm2 logs

# Restart app
pm2 restart all

# Stop app
pm2 stop all

# Delete app
pm2 delete all
```

## Monitoring

```bash
# Enable monitoring
pm2 monitortype --interval 10000

# View stats
pm2 stats
```

## Logging

```bash
# Rotate logs
pm2 rotate logs

# Save log
pm2 save

# Load saved PM2 process list
pm2 startup
pm2 save
```

## NPM Scripts

Update `package.json` with PM2 scripts:

```json
{
  "scripts": {
    "start": "npm run build && pm2 start ecosystem.config.js",
    "pm2:start": "pm2 start ecosystem.config.js",
    "pm2:stop": "pm2 stop all",
    "pm2:restart": "pm2 restart all",
    "pm2:logs": "pm2 logs",
    "pm2:list": "pm2 list",
    "pm2:save": "pm2 save",
    "pm2:startup": "pm2 startup"
  }
}
```

## Production Build

```bash
# Build frontend
cd frontend
npm run build

# Start with PM2
cd ../..
npm run pm2:start
```

## Environment Variables

Store secrets in `.env` or use PM2 env:

```bash
# Set environment variable
pm2 set ecosystem.config.js:* env:SESSION_SECRET="your-secret"

# List all env variables
pm2 env ecosystem.config.js
```

## Backup Strategy

```bash
# Create database backup
npm run backup

# Schedule backup with cron
0 2 * * * /path/to/db/backup.sh
```

## Scaling

For horizontal scaling, configure multiple instances:

```javascript
{
  instances: 'max',
  exec_mode: 'cluster',
  watch: false
}
```

## Auto-restart on reboot

```bash
pm2 startup
pm2 save
```