System Improvements

1. MPesa Callback Optimization

Current State: Using PHP bridge endpoint (/hj/c.php) as intermediary
Improvement Plan:

Implementation Steps:

1. Create dedicated endpoint in main system (/api/mpesa/webhook)
2. Update Safaricom portal with new callback URL
3. Implement:
   • IP whitelisting (Safaricom IP ranges)
   • Request signature validation
   • Idempotency handling
4. Maintain legacy bridge during transition period

Backup Protocol:

• Daily: Database snapshots (retain 7 days)
• Weekly: Full system backups (retain 4 weeks)
• Real-time: Transaction log streaming to S3

3. IoT Device Reliability Enhancements

Network Resilience Plan:

1. Connection Handling:

import time
from typing import Optional

# Configuration constants
MAX_RETRIES = 5
MIN_SIGNAL = 20  # Minimum RSSI signal strength
RETRY_DELAY = [5, 15, 30, 60, 120]  # Progressive backoff delays in seconds

class IoTDevice:
    def __init__(self):
        self.data_buffer = []
        
    def check_network_strength(self) -> int:
        """Simulate checking network signal strength
        Returns RSSI value (higher is better)"""
        # Implementation would use actual hardware API
        return 25  # Mock value
        
    def send_data_via_mqtt(self, data: dict) -> bool:
        """Attempt to send data via MQTT
        Returns True if successful"""
        # Implementation would use MQTT client
        try:
            # mqtt_client.publish(topic, payload)
            return True
        except Exception:
            return False
            
    def store_local_backup(self, data: dict) -> None:
        """Store data locally if transmission succeeds"""
        self.data_buffer.append(data)
        # Would typically write to flash storage
        print(f"Data backed up locally: {data}")
        
    def enter_low_power_mode(self, delay_seconds: int) -> None:
        """Enter low power mode for specified duration"""
        print(f"Entering low power mode for {delay_seconds} seconds")
        time.sleep(delay_seconds)  # In real device, would use proper sleep mode
        
    def transmit_data(self, payload: dict) -> bool:
        """Attempt to transmit data with retry logic
        Returns True if transmission succeeded"""
        retries = 0
        
        while retries < MAX_RETRIES:
            current_signal = self.check_network_strength()
            
            if current_signal >= MIN_SIGNAL:
                print(f"Attempt {retries + 1}: Trying transmission...")
                if self.send_data_via_mqtt(payload):
                    self.store_local_backup(payload)
                    print("Transmission successful!")
                    return True
                    
    from typing import Optional

    # Configuration constants
    MAX_RETRIES = 5
    MIN_SIGNAL = 20  # Minimum RSSI signal strength
    RETRY_DELAY = [5, 15, 30, 60, 120]  # Progressive backoff delays in seconds

    claretries += 1
                
    print("Max retries exceeded. Transmission failed.")
    return False


# Example usage
if __name__ == "__main__":
    device = IoTDevice()
    sample_data = {
        "device_id": "agripad_001",
        "timestamp": int(time.time()),
        "temperature": 23.5,
        "humidity": 65.2
    }
    
    success = device.transmit_data(sample_data)
    print(f"Final transmission status: {'Success' if success else 'Failure'}")

2. Field Testing Matrix:

   Test Case	Success Criteria
   No network	Data cached for 72+ hours
   Intermittent signal	Automatic retry (3 attempts)
   Low battery	Graceful shutdown with save

4. Agripad Device List Management

Always update devices from the Agripad Dashboard to capture the most recent in order to transmist data as expected to the right system.