Re_Backend/TAT_QUICK_START.md

# ⏰ TAT Notifications - Quick Start Guide

## 🎯 Goal
Get TAT (Turnaround Time) notifications working in **under 5 minutes**!

---

## ✅ Step 1: Setup Redis (Required)

### 🚀 Option A: Upstash (RECOMMENDED - No Installation!)

**Best for Windows/Development - 100% Free**

1. **Sign up**: Go to https://console.upstash.com/
2. **Create Database**: Click "Create Database"
   - Name: `redis-tat-dev`
   - Type: Regional
   - Region: Choose closest to you
   - Click "Create"
3. **Copy Connection URL**: You'll get a URL like:
   ```
   rediss://default:AbCd1234...@us1-mighty-shark-12345.upstash.io:6379
   ```
4. **Update `.env` in Re_Backend/**:
   ```bash
   REDIS_URL=rediss://default:AbCd1234...@us1-mighty-shark-12345.upstash.io:6379
   ```

✅ **Done!** No installation, no setup, works everywhere!

---

### Alternative: Docker (If you prefer local)

If you have Docker Desktop:
```bash
docker run -d --name redis-tat -p 6379:6379 redis:latest
```

Then in `.env`:
```bash
REDIS_URL=redis://localhost:6379
```

---

## ⚡ Step 2: Enable Test Mode (HIGHLY RECOMMENDED)

For testing, enable **fast mode** where **1 hour = 1 minute**:

### Edit `.env` file in `Re_Backend/`:
```bash
TAT_TEST_MODE=true
```

This means:
- ✅ 6-hour TAT = 6 minutes (instead of 6 hours)
- ✅ 48-hour TAT = 48 minutes (instead of 48 hours)
- ✅ Perfect for quick testing!

---

## 🚀 Step 3: Restart Backend

```bash
cd Re_Backend
npm run dev
```

### You Should See:
```
✅ [TAT Queue] Connected to Redis
✅ [TAT Worker] Initialized and listening
⏰ TAT Configuration:
   - Test Mode: ENABLED (1 hour = 1 minute)
   - Redis: rediss://***@upstash.io:6379
```

💡 If you see connection errors, double-check your `REDIS_URL` in `.env`

---

## 🧪 Step 4: Test It!

### Create a Request:
1. **Frontend**: Create a new workflow request
2. **Set TAT**: 6 hours (becomes 6 minutes in test mode)
3. **Submit** the request

### Watch the Magic:
```
✨ At 3 minutes:  ⏳ 50% notification
✨ At 4.5 minutes: ⚠️ 75% notification  
✨ At 6 minutes:   ⏰ 100% breach notification
```

### Check Logs:
```bash
# You'll see:
[TAT Scheduler] ✅ TAT jobs scheduled for request...
[TAT Processor] Processing tat50 for request...
[TAT Processor] tat50 notification sent for request...
```

---

## 📊 Verify in Database

```sql
SELECT 
  approver_name,
  tat_hours,
  tat50_alert_sent,
  tat75_alert_sent,
  tat_breached,
  status
FROM approval_levels
WHERE status = 'IN_PROGRESS';
```

You should see the flags change as notifications are sent!

---

## ❌ Troubleshooting

### "ECONNREFUSED" or Connection Error?
**Problem**: Can't connect to Redis

**Solution**:
1. **Check `.env` file**:
   ```bash
   # Make sure REDIS_URL is set correctly
   REDIS_URL=rediss://default:YOUR_PASSWORD@YOUR_URL.upstash.io:6379
   ```

2. **Verify Upstash Database**:
   - Go to https://console.upstash.com/
   - Check database status (should be "Active")
   - Copy connection URL again if needed

3. **Test Connection**:
   - Use Upstash's Redis CLI in their console
   - Or install `redis-cli` and test:
     ```bash
     redis-cli -u "rediss://default:YOUR_PASSWORD@YOUR_URL.upstash.io:6379" ping
     # Should return: PONG
     ```

### No Notifications?
**Checklist**:
- ✅ REDIS_URL set in `.env`?
- ✅ Backend restarted after setting REDIS_URL?
- ✅ TAT_TEST_MODE=true in `.env`?
- ✅ Request submitted (not just created)?
- ✅ Logs show "Connected to Redis"?

### Still Issues?
```bash
# Check detailed logs
Get-Content Re_Backend/logs/app.log -Tail 50 -Wait

# Look for:
# ✅ [TAT Queue] Connected to Redis
# ❌ [TAT Queue] Redis connection error
```

---

## 🎓 Testing Scenarios

### Quick Test (6 minutes):
```
TAT: 6 hours (6 minutes in test mode)
├─ 3 min   ⏳ 50% reminder
├─ 4.5 min ⚠️ 75% warning
└─ 6 min   ⏰ 100% breach
```

### Medium Test (24 minutes):
```
TAT: 24 hours (24 minutes in test mode)
├─ 12 min  ⏳ 50% reminder
├─ 18 min  ⚠️ 75% warning
└─ 24 min  ⏰ 100% breach
```

---

## 📚 More Information

- **Full Documentation**: `Re_Backend/docs/TAT_NOTIFICATION_SYSTEM.md`
- **Testing Guide**: `Re_Backend/docs/TAT_TESTING_GUIDE.md`
- **Redis Setup**: `Re_Backend/INSTALL_REDIS.txt`

---

## 🎉 Production Mode

When ready for production:

1. **Disable Test Mode**:
   ```bash
   # In .env
   TAT_TEST_MODE=false
   ```

2. **Restart Backend**

3. **TAT will now use real hours**:
   - 48-hour TAT = actual 48 hours
   - Working hours: Mon-Fri, 9 AM - 6 PM

---

## 🆘 Need Help?

Common fixes:

### 1. Verify Upstash Connection
```bash
# In Upstash Console (https://console.upstash.com/)
# - Click your database
# - Use the "CLI" tab to test: PING
# - Should return: PONG
```

### 2. Check Environment Variables
```bash
# In Re_Backend/.env, verify:
REDIS_URL=rediss://default:YOUR_PASSWORD@YOUR_URL.upstash.io:6379
TAT_TEST_MODE=true
```

### 3. Clear Redis Queue (if needed)
```bash
# In Upstash Console CLI tab:
FLUSHALL
# This clears all jobs - use only if you need a fresh start
```

### 4. Restart Backend
```bash
cd Re_Backend
npm run dev
```

### 5. Check Logs
```bash
Get-Content logs/app.log -Tail 50 -Wait
```

---

**Status Check**:
- [ ] Upstash Redis database created
- [ ] REDIS_URL copied to `.env`
- [ ] TAT_TEST_MODE=true in `.env`
- [ ] Backend restarted
- [ ] Logs show "TAT Queue: Connected to Redis"
- [ ] Test request submitted

✅ All checked? **You're ready!**

---

**Last Updated**: November 4, 2025  
**Author**: Royal Enfield Workflow Team