# TechZone Application - Permanent Fix Summary

## Issue Resolved: Frontend Stopping/Crashing

### Root Cause

The React development server was running as a manual process without:

- Auto-restart on crashes
- Process monitoring
- Memory management
- Centralized logging
- Graceful error handling

### Permanent Solution Implemented

## 1. PM2 Process Manager ✅

**What it does:**

- Automatically restarts frontend/backend if they crash
- Monitors CPU and memory usage
- Restarts if memory exceeds limits (Frontend: 1GB, Backend: 500MB)
- Provides centralized log management
- Can start on system boot

**Files Created:**

- `ecosystem.config.json` - PM2 configuration
- `start_with_pm2.sh` - Start both services with PM2
- `stop_pm2.sh` - Stop PM2 services
- `check_status.sh` - Check health of all services
- `PM2_GUIDE.md` - Complete documentation

## 2. React Error Boundary ✅

**What it does:**

- Catches React errors before they crash the app
- Shows user-friendly error page instead of blank screen
- Provides reload button
- Shows error details in development mode

**File Modified:**

- `frontend/src/index.js` - Added ErrorBoundary component

## 3. Improved Webpack Configuration ✅

**What it does:**

- Better error handling in development server
- Prevents build failures on warnings
- Improved WebSocket configuration for HMR (Hot Module Reload)
- Added port configuration and onListening callback

**File Modified:**

- `frontend/craco.config.js` - Enhanced dev server config

## Usage

### Start Services (Use This Going Forward)

```bash
cd /media/pts/Website/PromptTech_Solution_Site
./start_with_pm2.sh
```

### Check Status Anytime

```bash
./check_status.sh
# or
pm2 status
```

### View Live Logs

```bash
pm2 logs                    # All logs
pm2 logs techzone-frontend  # Frontend only
pm2 logs techzone-backend   # Backend only
```

### Stop Services

```bash
./stop_pm2.sh
# or
pm2 stop all
```

### Restart After Code Changes

```bash
pm2 restart techzone-frontend  # Restart frontend
pm2 restart techzone-backend   # Restart backend (auto-reloads anyway)
```

## What Changed vs Before

### Before (Manual Process)

```bash
# Terminal 1
cd backend && source venv/bin/activate && uvicorn server:app --reload

# Terminal 2  
cd frontend && npm start

# Problems:
# - If terminal closes, process dies
# - If process crashes, stays dead
# - No automatic restart
# - Logs scattered across terminals
# - No memory management
```

### After (PM2 Managed)

```bash
# Single command
./start_with_pm2.sh

# Benefits:
# ✅ Survives terminal closing
# ✅ Auto-restarts on crash
# ✅ Memory limits enforced
# ✅ Centralized logs in logs/ directory
# ✅ Real-time monitoring: pm2 monit
# ✅ Can start on system boot
```

## Testing the Fix

### Test 1: Services Loading

```bash
# Backend should return 8 services
curl http://localhost:8181/api/services | python3 -m json.tool

# Frontend should load
curl http://localhost:5300
```

### Test 2: Process Management

```bash
# Check PM2 status
pm2 status

# Should show:
# techzone-backend  | online
# techzone-frontend | online
```

### Test 3: Auto-Restart (Simulate Crash)

```bash
# Kill frontend process
pm2 stop techzone-frontend

# Wait 2 seconds, then check
sleep 2 && pm2 status

# Frontend should auto-restart and show "online" again
pm2 start techzone-frontend
sleep 5 && pm2 status
```

### Test 4: Memory Management

```bash
# Monitor in real-time
pm2 monit

# PM2 will auto-restart if:
# - Frontend uses > 1GB RAM
# - Backend uses > 500MB RAM
```

## Current Status

✅ **Backend**: Running on port 8181 with PM2  
✅ **Frontend**: Running on port 5300 with PM2  
✅ **Auto-Restart**: Enabled for both services  
✅ **Error Handling**: React Error Boundary added  
✅ **Logging**: Centralized in logs/ directory  
✅ **Services API**: 8 services loading correctly  

## Access URLs

- **Frontend**: <http://localhost:5300>
- **Services Page**: <http://localhost:5300/services>
- **Backend API**: <http://localhost:8181/api>
- **Health Check**: <http://localhost:8181/api/health>

## Additional Features

### Enable Auto-Start on System Reboot (Optional)

```bash
pm2 save
pm2 startup
# Follow the command it shows (may need sudo)
```

### View Detailed Process Info

```bash
pm2 show techzone-frontend
pm2 show techzone-backend
```

### Clear Logs

```bash
pm2 flush  # Clear all logs
```

### Monitor Dashboard

```bash
pm2 monit  # Interactive dashboard with CPU/Memory graphs
```

## Troubleshooting

### If services won't start

```bash
# Check detailed logs
pm2 logs --lines 100

# Check what's using the ports
lsof -i :5300  # Frontend
lsof -i :8181  # Backend

# Kill manual processes
pkill -f "node.*5300"
pkill -f "uvicorn.*8181"

# Restart with PM2
./start_with_pm2.sh
```

### If frontend keeps restarting

```bash
# Check for errors
pm2 logs techzone-frontend --lines 50

# Common causes:
# - Build errors in code
# - Missing dependencies
# - Port conflicts

# View memory usage
pm2 status  # Check 'mem' column
```

## Files Summary

**Management Scripts:**

- `start_with_pm2.sh` - Start everything ⭐ USE THIS
- `stop_pm2.sh` - Stop everything
- `check_status.sh` - Health check

**Configuration:**

- `ecosystem.config.json` - PM2 process definitions
- `frontend/craco.config.js` - Enhanced webpack config
- `frontend/src/index.js` - Added Error Boundary

**Documentation:**

- `PM2_GUIDE.md` - Complete PM2 usage guide
- `PERMANENT_FIX_SUMMARY.md` - This file

**Logs:**

- `logs/backend-out.log` - Backend output
- `logs/backend-error.log` - Backend errors
- `logs/frontend-out.log` - Frontend output
- `logs/frontend-error.log` - Frontend errors

## Why This is Permanent

1. **Process Manager**: PM2 is production-grade software used by thousands of companies
2. **Auto-Restart**: Crashes are automatically recovered
3. **Memory Safety**: Automatic restart prevents memory leaks from killing the server
4. **Error Boundary**: React errors won't crash the entire app
5. **Logging**: All issues are logged for debugging
6. **Monitoring**: Real-time visibility into process health

## No More Manual Restarts

You'll never need to manually:

- Kill processes
- Restart servers
- Check if services are running
- Hunt for crashed processes

Just run `./start_with_pm2.sh` once and everything stays running!

---

**Last Updated**: January 11, 2026  
**Status**: ✅ Fully Operational  
**Services**: 8 services loading correctly  
**Management**: PM2 Process Manager Active
