spore/README.md

# SPORE

> **S**Procket **OR**chestration **E**ngine

SPORE is a cluster engine for ESP8266 microcontrollers that provides automatic node discovery, health monitoring, and over-the-air updates in a distributed network environment.

## Features

- **WiFi Management**: Automatic WiFi STA/AP configuration with MAC-based hostname generation
- **Auto Discovery**: UDP-based node discovery with automatic cluster membership
- **Service Registry**: Dynamic API endpoint discovery and registration
- **Health Monitoring**: Real-time node status tracking with resource monitoring
- **Event System**: Local and cluster-wide event publishing/subscription
- **Over-The-Air Updates**: Seamless firmware updates across the cluster
- **REST API**: HTTP-based cluster management and monitoring

## Supported Hardware

- **ESP-01** (1MB Flash)
- **ESP-01S** (1MB Flash)
- Other ESP8266 boards with 1MB+ flash

## Architecture

### Core Components

The system architecture consists of several key components working together:

- **Network Manager**: WiFi connection handling and hostname configuration
- **Cluster Manager**: Node discovery, member list management, and health monitoring
- **API Server**: HTTP API server with dynamic endpoint registration
- **Task Scheduler**: Cooperative multitasking system for background operations
- **Node Context**: Central context providing event system and shared resources

### Auto Discovery Protocol

The cluster uses a UDP-based discovery protocol for automatic node detection:

1. **Discovery Broadcast**: Nodes periodically send UDP packets on port 4210
2. **Response Handling**: Nodes respond with their hostname and IP address
3. **Member Management**: Discovered nodes are automatically added to the cluster
4. **Health Monitoring**: Continuous status checking via HTTP API calls

### Task Scheduling

The system runs several background tasks at different intervals:

- **Discovery Tasks**: Send/listen for discovery packets (1s/100ms)
- **Status Updates**: Monitor cluster member health (1s)
- **Heartbeat**: Maintain cluster connectivity (2s)
- **Member Info**: Update detailed node information (10s)
- **Debug Output**: Print cluster status (5s)

## API Endpoints

### Node Management

| Endpoint | Method | Description |
|----------|--------|-------------|
| `/api/node/status` | GET | Get system resources and API endpoints |
| `/api/node/update` | POST | Upload and install firmware update |
| `/api/node/restart` | POST | Restart the node |

### Cluster Management

| Endpoint | Method | Description |
|----------|--------|-------------|
| `/api/cluster/members` | GET | Get cluster membership and status |

### Node Status Response

```json
{
  "freeHeap": 12345,
  "chipId": 12345678,
  "sdkVersion": "2.2.2-dev(38a443e)",
  "cpuFreqMHz": 80,
  "flashChipSize": 1048576,
  "api": [
    {
      "uri": "/api/node/status",
      "method": "GET"
    }
  ]
}
```

### Cluster Members Response

```json
{
  "members": [
    {
      "hostname": "esp_123456",
      "ip": "192.168.1.100",
      "lastSeen": 1234567890,
      "latency": 5,
      "status": "active",
      "resources": {
        "freeHeap": 12345,
        "chipId": 12345678,
        "sdkVersion": "2.2.2-dev(38a443e)",
        "cpuFreqMHz": 80,
        "flashChipSize": 1048576
      },
      "api": [
        {
          "uri": "/api/node/status",
          "method": "GET"
        }
      ]
    }
  ]
}
```

## Configuration

### Environment Setup

Create a `.env` file in your project root:

```bash
# API node IP for cluster management
export API_NODE=192.168.1.100
```

### PlatformIO Configuration

The project uses PlatformIO with the following configuration:

- **Framework**: Arduino
- **Board**: ESP-01 with 1MB flash
- **Upload Speed**: 115200 baud
- **Flash Mode**: DOUT (required for ESP-01S)

### Dependencies

The project requires the following libraries:
- `esp32async/ESPAsyncWebServer@^3.8.0` - HTTP API server
- `bblanchon/ArduinoJson@^7.4.2` - JSON processing
- `arkhipenko/TaskScheduler@^3.8.5` - Cooperative multitasking

## Development

### Prerequisites

- PlatformIO Core or PlatformIO IDE
- ESP8266 development tools
- `jq` for JSON processing in scripts

### Building

Build the firmware:

```bash
./ctl.sh build
```

### Flashing

Flash firmware to a connected device:

```bash
./ctl.sh flash
```

### Over-The-Air Updates

Update a specific node:

```bash
./ctl.sh ota update 192.168.1.100
```

Update all nodes in the cluster:

```bash
./ctl.sh ota all
```

### Cluster Management

View cluster members:

```bash
./ctl.sh cluster members
```

## Implementation Details

### Event System

The `NodeContext` provides an event-driven architecture:

```cpp
// Subscribe to events
ctx.on("node_discovered", [](void* data) {
    NodeInfo* node = static_cast<NodeInfo*>(data);
    // Handle new node discovery
});

// Publish events
ctx.fire("node_discovered", &newNode);
```

### Node Status Tracking

Nodes are automatically categorized by their activity:

- **ACTIVE**: Responding within 10 seconds
- **INACTIVE**: No response for 10-60 seconds  
- **DEAD**: No response for over 60 seconds

### Resource Monitoring

Each node tracks:
- Free heap memory
- Chip ID and SDK version
- CPU frequency
- Flash chip size
- API endpoint registry

### WiFi Fallback

The system includes automatic WiFi fallback:
1. Attempts to connect to configured WiFi network
2. If connection fails, creates an access point
3. Hostname is automatically generated from MAC address

## Task Management

The SPORE system includes a comprehensive TaskManager that provides a clean interface for managing system tasks. This makes it easy to add, configure, and control background tasks without cluttering the main application code.

### TaskManager Features

- **Easy Task Registration**: Simple API for adding new tasks with configurable intervals
- **Dynamic Control**: Enable/disable tasks at runtime
- **Interval Management**: Change task execution frequency on the fly
- **Status Monitoring**: View task status and configuration
- **Automatic Lifecycle**: Tasks are automatically managed and executed

### Basic Usage

```cpp
#include "TaskManager.h"

// Create task manager
TaskManager taskManager(ctx);

// Register tasks
taskManager.registerTask("heartbeat", 2000, heartbeatFunction);
taskManager.registerTask("maintenance", 30000, maintenanceFunction);

// Initialize and start all tasks
taskManager.initialize();
```

#### Using std::bind with Member Functions

```cpp
#include <functional>
#include "TaskManager.h"

class MyService {
public:
    void sendHeartbeat() {
        Serial.println("Service heartbeat");
    }
    
    void performMaintenance() {
        Serial.println("Running maintenance");
    }
};

MyService service;
TaskManager taskManager(ctx);

// Register member functions using std::bind
taskManager.registerTask("heartbeat", 2000, 
                       std::bind(&MyService::sendHeartbeat, &service));
taskManager.registerTask("maintenance", 30000, 
                       std::bind(&MyService::performMaintenance, &service));

// Initialize and start all tasks
taskManager.initialize();
```

#### Using Lambda Functions

```cpp
// Register lambda functions directly
taskManager.registerTask("counter", 1000, []() {
    static int count = 0;
    Serial.printf("Count: %d\n", ++count);
});

// Lambda with capture
int threshold = 100;
taskManager.registerTask("monitor", 5000, [&threshold]() {
    if (ESP.getFreeHeap() < threshold) {
        Serial.println("Low memory warning!");
    }
});
```

#### Complex Task Registration

```cpp
class NetworkManager {
public:
    void checkConnection() { /* ... */ }
    void sendData(String data) { /* ... */ }
};

NetworkManager network;

// Multiple operations in one task
taskManager.registerTask("network_ops", 3000, 
                       std::bind([](NetworkManager* net) {
                           net->checkConnection();
                           net->sendData("status_update");
                       }, &network));
```

### Task Control API

```cpp
// Enable/disable tasks
taskManager.enableTask("heartbeat");
taskManager.disableTask("maintenance");

// Change intervals
taskManager.setTaskInterval("heartbeat", 5000);  // 5 seconds

// Check status
bool isRunning = taskManager.isTaskEnabled("heartbeat");
unsigned long interval = taskManager.getTaskInterval("heartbeat");

// Print all task statuses
taskManager.printTaskStatus();
```

### Remote Task Management

The TaskManager integrates with the API server to provide remote task control:

```bash
# Get task status
curl http://192.168.1.100/api/tasks/status

# Control tasks
curl -X POST http://192.168.1.100/api/tasks/control \
  -d "task=heartbeat&action=disable"

# Available actions: enable, disable, start, stop
```

### Adding Custom Tasks

#### Method 1: Using std::bind (Recommended)

1. **Create your service class**:
   ```cpp
   class SensorService {
   public:
       void readTemperature() {
           // Read sensor logic
           Serial.println("Reading temperature");
       }
       
       void calibrateSensors() {
           // Calibration logic
           Serial.println("Calibrating sensors");
       }
   };
   ```

2. **Register with TaskManager**:
   ```cpp
   SensorService sensors;
   
   taskManager.registerTask("temp_read", 1000, 
                          std::bind(&SensorService::readTemperature, &sensors));
   taskManager.registerTask("calibrate", 60000, 
                          std::bind(&SensorService::calibrateSensors, &sensors));
   ```

#### Method 2: Traditional Functions

1. **Define your task function**:
   ```cpp
   void myCustomTask() {
       // Your task logic here
       Serial.println("Custom task executed");
   }
   ```

2. **Register with TaskManager**:
   ```cpp
   taskManager.registerTask("my_task", 10000, myCustomTask);
   ```

### Task Configuration Options

When registering tasks, you can specify:

- **Name**: Unique identifier for the task
- **Interval**: Execution frequency in milliseconds
- **Callback**: Function, bound method, or lambda to execute
- **Enabled**: Whether the task starts enabled (default: true)
- **AutoStart**: Whether to start automatically (default: true)

```cpp
// Traditional function
taskManager.registerTask("delayed_task", 5000, taskFunction, true, false);

// Member function with std::bind
taskManager.registerTask("service_task", 3000, 
                       std::bind(&Service::method, &instance), true, false);

// Lambda function
taskManager.registerTask("lambda_task", 2000, 
                       []() { Serial.println("Lambda!"); }, true, false);
```

## Current Limitations

- WiFi credentials are hardcoded in `Config.cpp` (should be configurable)
- Limited error handling for network failures
- No persistent storage for configuration
- Basic health monitoring without advanced metrics

## Troubleshooting

### Common Issues

1. **Discovery Failures**: Check UDP port 4210 is not blocked
2. **WiFi Connection**: Verify SSID/password in Config.cpp
3. **OTA Updates**: Ensure sufficient flash space (1MB minimum)
4. **Cluster Split**: Check network connectivity between nodes

### Debug Output

Enable serial monitoring to see cluster activity:

```bash
pio device monitor
```

## Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Test thoroughly on ESP8266 hardware
5. Submit a pull request

## License

[Add your license information here]

## Acknowledgments

- Built with [PlatformIO](https://platformio.org/)
- Uses [TaskScheduler](https://github.com/arkhipenko/TaskScheduler) for cooperative multitasking
- [ESPAsyncWebServer](https://github.com/me-no-dev/ESPAsyncWebServer) for HTTP API
- [ArduinoJson](https://arduinojson.org/) for JSON processing