implemented keep alive (clients that have not sent the KeepAlive command for more than ten seconds will be disconnected)

vscode/OmobiLEDdisplayBluetooth/include/BluetoothLeUartServer.h

@@ -60,10 +60,11 @@ public:
     void sendData(String data);
 
     bool getDeviceConnected();
+    bool disconnectCurrentDevice();
 
 protected:
     // callbacks for BLEServer
-    void onConnect(BLEServer *pServer) override;
+    void onConnect(BLEServer *pServer, esp_ble_gatts_cb_param_t *param) override;
     void onDisconnect(BLEServer *pServer) override;
 
     // callback for BLECharacteristic
@@ -75,6 +76,9 @@ private:
     const char *rxUUID;
     const char *txUUID;
 
+
+	esp_gatt_perm_t permissions;
+
     // BLE Objects
     BLEServer *bleServer;
     BLEService *bleService;
@@ -82,7 +86,8 @@ private:
     BLECharacteristic *rxCharacteristic;
 
     // helpers
-    bool deviceConnected = false;
+    bool deviceConnected;
+    uint16_t deviceConnectionId;
     BluetoothLeUartServerCallbacks *callbacks;
 };
 

vscode/OmobiLEDdisplayBluetooth/include/OmobiLedDisplay.h

@@ -15,6 +15,8 @@ public:
     // befriend for callbacks
     friend class BluetoothLeUartServer;
 
+    void loop();
+
 protected:
     // calbacks for BluetoothLeUartServerCallbacks
     void onDeviceConnectedChanged(bool deviceConnected) override;
@@ -23,6 +25,8 @@ protected:
 private:
     enum OmobiDisplayCommand
     {
+        AuthorizeSessionCommand = 0,
+        KeepAliveCommand = 1,
         GetAllTextSetsCommand = 10,
         GetTextSetParameterCommand = 11,
         GetDisplayBrightnessCommand = 12,
@@ -37,6 +41,9 @@ private:
         DisplayControllerError = 501
     };
 
+    unsigned long lastKeepAlive;
+    const int maximumKeepAliveDelay = 10000;
+
     LedDisplayController *ledDisplayController;
     BluetoothLeUartServer *bleServer;
 };

vscode/OmobiLEDdisplayBluetooth/src/BluetoothLeUartServer.cpp

@@ -7,6 +7,8 @@ BluetoothLeUartServer::BluetoothLeUartServer(String deviceName, const char uartS
     this->txUUID = txUUID;
 
     this->callbacks = nullptr;
+    this->deviceConnected = false;
+    this->deviceConnectionId = -1;
 
     // Create the BLE Device
     BLEDevice::init(deviceName.c_str()); // Give it a name
@@ -54,9 +56,11 @@ void BluetoothLeUartServer::sendData(String data)
     txCharacteristic->notify();
 }
 
-void BluetoothLeUartServer::onConnect(BLEServer *pServer)
+void BluetoothLeUartServer::onConnect(BLEServer* pServer, esp_ble_gatts_cb_param_t *param)
 {
     this->deviceConnected = true;
+    this->deviceConnectionId = param->connect.conn_id;
+
     if (this->callbacks != nullptr)
     {
         this->callbacks->onDeviceConnectedChanged(this->deviceConnected);
@@ -66,6 +70,8 @@ void BluetoothLeUartServer::onConnect(BLEServer *pServer)
 void BluetoothLeUartServer::onDisconnect(BLEServer *pServer)
 {
     this->deviceConnected = false;
+    this->deviceConnectionId = -1;
+
     if (this->callbacks != nullptr)
         this->callbacks->onDeviceConnectedChanged(this->deviceConnected);
 }
@@ -79,4 +85,12 @@ void BluetoothLeUartServer::onWrite(BLECharacteristic *rxCharacteristic)
 bool BluetoothLeUartServer::getDeviceConnected()
 {
     return this->deviceConnected;
+}
+
+bool BluetoothLeUartServer::disconnectCurrentDevice() {
+    if(!this->getDeviceConnected())
+        return false;
+
+    this->bleServer->disconnect(this->deviceConnectionId);
+    return true;
 }

vscode/OmobiLEDdisplayBluetooth/src/OmobiLedDisplay.cpp

@@ -1,22 +1,34 @@
 #include "OmobiLedDisplay.h"
+#include "esp_gatts_api.h"
 
 OmobiLedDisplay::OmobiLedDisplay(String deviceName, Adafruit_NeoMatrix *ledDisplayMatrix)
 {
+    this->lastKeepAlive = -1;
+
     // init led display controller
     this->ledDisplayController = new LedDisplayController(ledDisplayMatrix);
     this->ledDisplayController->setTextSetParameter(0, LedDisplayController::ActiveParameter, "true");
 
     // init ble server
-    this->bleServer = new BluetoothLeUartServer(deviceName, "6e400001-b5a3-f393-e0a9-e50e24dcca9e", "6e400002-b5a3-f393-e0a9-e50e24dcca9e", "6e400003-b5a3-f393-e0a9-e50e24dcca9e");
+    this->bleServer = new BluetoothLeUartServer(deviceName, "92fecb20-1406-426a-afa5-cd5c1f306462", "92fecb21-1406-426a-afa5-cd5c1f306462", "92fecb22-1406-426a-afa5-cd5c1f306462");
     this->bleServer->setCallbacks(this);
 }
 
+void OmobiLedDisplay::loop() {
+    if(millis() - lastKeepAlive > this->maximumKeepAliveDelay)
+        this->bleServer->disconnectCurrentDevice();
+}
+
 void OmobiLedDisplay::onDeviceConnectedChanged(bool deviceConnected)
 {
-    if (deviceConnected)
+    if (deviceConnected) {
         Serial.println("Device connected");
-    else
+        this->lastKeepAlive = millis();
+    }
+    else {
         Serial.println("Device disconnected");
+        this->lastKeepAlive = -1;
+    }
 }
 
 void OmobiLedDisplay::onDataReceived(String dataString)
@@ -42,6 +54,13 @@ void OmobiLedDisplay::onDataReceived(String dataString)
 
     switch (requestHeader)
     {
+    case KeepAliveCommand:
+    {
+        replyStatus = Success;
+        this->lastKeepAlive = millis();
+        break;
+    }
+
     case GetAllTextSetsCommand:
     {
         // cycle through all text sets

vscode/OmobiLEDdisplayBluetooth/src/main.cpp

@@ -27,5 +27,6 @@ void setup()
 void loop()
 {
   // nothing to do in loop
-  delay(1000);
+  display->loop();
+  delay(1);
 }