Rewrite LORAWAN Arduino Cloud driver for better clarity

Author: aentinger

src/ArduinoIoTCloud.cpp

@@ -172,38 +172,10 @@ Property& ArduinoIoTCloudClass::addPropertyReal(String& property, String name, i
  * PROTECTED MEMBER FUNCTIONS
  ******************************************************************************/
 
-NetworkConnectionState ArduinoIoTCloudClass::checkPhyConnection()
-{
-  NetworkConnectionState const connect_state = _connection->check();
-
-  if (_connection->check() != NetworkConnectionState::CONNECTED)
-  {
-    if (_iot_status == ArduinoIoTConnectionStatus::CONNECTED)
-    {
-      disconnect();
-    }
-  }
-
-  return connect_state;
-}
-
 void ArduinoIoTCloudClass::execCloudEventCallback(ArduinoIoTCloudEvent const event)
 {
   OnCloudEventCallback callback = _cloud_event_callback[static_cast<size_t>(event)];
   if (callback) {
     (*callback)();
   }
 }
-
-void ArduinoIoTCloudClass::printConnectionStatus(ArduinoIoTConnectionStatus status)
-{
-  switch (status)
-  {
-    case ArduinoIoTConnectionStatus::IDLE:         DBG_INFO   ("Arduino IoT Cloud Connection status: IDLE");         break;
-    case ArduinoIoTConnectionStatus::ERROR:        DBG_ERROR("Arduino IoT Cloud Connection status: ERROR");        break;
-    case ArduinoIoTConnectionStatus::CONNECTING:   DBG_INFO   ("Arduino IoT Cloud Connection status: CONNECTING");   break;
-    case ArduinoIoTConnectionStatus::RECONNECTING: DBG_INFO   ("Arduino IoT Cloud Connection status: RECONNECTING"); break;
-    case ArduinoIoTConnectionStatus::CONNECTED:    DBG_INFO   ("Arduino IoT Cloud Connection status: CONNECTED");    break;
-    case ArduinoIoTConnectionStatus::DISCONNECTED: DBG_ERROR("Arduino IoT Cloud Connection status: DISCONNECTED"); break;
-  }
-}

src/ArduinoIoTCloud.h

@@ -38,6 +38,8 @@
 #include "property/types/CloudWrapperInt.h"
 #include "property/types/CloudWrapperString.h"
 
+#include "utility/time/TimeService.h"
+
 /******************************************************************************
    TYPEDEF
  ******************************************************************************/
@@ -91,6 +93,8 @@ class ArduinoIoTCloudClass
 
     inline ConnectionHandler * getConnection()          { return _connection; }
 
+    inline unsigned long getTime() { return _time_service.getTime(); }
+
     void addCallback(ArduinoIoTCloudEvent const event, OnCloudEventCallback callback);
 
 #define addProperty( v, ...) addPropertyReal(v, #v, __VA_ARGS__)
@@ -131,18 +135,11 @@ class ArduinoIoTCloudClass
 
   protected:
 
-    virtual int  connect   () = 0;
-    virtual void disconnect() = 0;
-
-    inline ArduinoIoTConnectionStatus getIoTStatus() { return _iot_status; }
-
     ConnectionHandler * _connection = nullptr;
     PropertyContainer _property_container;
-    ArduinoIoTConnectionStatus _iot_status = ArduinoIoTConnectionStatus::IDLE;
+    TimeService _time_service;
 
-           NetworkConnectionState checkPhyConnection();
-           void execCloudEventCallback(ArduinoIoTCloudEvent const event);
-    static void printConnectionStatus(ArduinoIoTConnectionStatus status);
+    void execCloudEventCallback(ArduinoIoTCloudEvent const event);
 
   private:
 

src/ArduinoIoTCloudLPWAN.cpp

@@ -33,12 +33,22 @@
 
 static size_t const CBOR_LORA_MSG_MAX_SIZE = 255;
 
+/******************************************************************************
+   LOCAL MODULE FUNCTIONS
+ ******************************************************************************/
+
+extern "C" unsigned long getTime()
+{
+  return ArduinoCloud.getTime();
+}
+
 /******************************************************************************
    CTOR/DTOR
  ******************************************************************************/
 
 ArduinoIoTCloudLPWAN::ArduinoIoTCloudLPWAN()
-: _retryEnable{false}
+: _state{State::ConnectPhy}
+, _retryEnable{false}
 , _maxNumRetry{5}
 , _intervalRetry{1000}
 {
@@ -58,45 +68,21 @@ int ArduinoIoTCloudLPWAN::begin(ConnectionHandler& connection, bool retry)
 {
   _connection = &connection;
   _retryEnable = retry;
+  _time_service.begin(nullptr);
   return 1;
 }
 
 void ArduinoIoTCloudLPWAN::update()
 {
-  // Check if a primitive property wrapper is locally changed
-  updateTimestampOnLocallyChangedProperties(_property_container);
-
-  ArduinoIoTConnectionStatus next_iot_status = _iot_status;
-
-  /* Since we do not have a direct connection to the Arduino IoT Cloud servers
-   * there is no such thing is a 'cloud connection state' since the LoRa
-   * board connection state to the gateway is all the information we have.
-   */
-  NetworkConnectionState const net_con_state = checkPhyConnection();
-  if     (net_con_state == NetworkConnectionState::CONNECTED)    { next_iot_status = ArduinoIoTConnectionStatus::CONNECTED;    execCloudEventCallback(ArduinoIoTCloudEvent::CONNECT); }
-  else if(net_con_state == NetworkConnectionState::CONNECTING)   { next_iot_status = ArduinoIoTConnectionStatus::CONNECTING; }
-  else if(net_con_state == NetworkConnectionState::DISCONNECTED) { next_iot_status = ArduinoIoTConnectionStatus::DISCONNECTED; execCloudEventCallback(ArduinoIoTCloudEvent::DISCONNECT); }
-
-  if(next_iot_status != _iot_status)
+  /* Run through the state machine. */
+  State next_state = _state;
+  switch (_state)
   {
-    printConnectionStatus(next_iot_status);
-    _iot_status = next_iot_status;
-  }
-
-  if(net_con_state != NetworkConnectionState::CONNECTED) return;
-
-  if (_connection->available()) {
-    uint8_t msgBuf[CBOR_LORA_MSG_MAX_SIZE];
-    uint8_t i = 0;
-    while (_connection->available()) {
-      msgBuf[i++] = _connection->read();
-    }
-
-    CBORDecoder::decode(_property_container, msgBuf, sizeof(msgBuf));
+  case State::ConnectPhy: next_state = handle_ConnectPhy(); break;
+  case State::SyncTime:   next_state = handle_SyncTime();   break;
+  case State::Connected:  next_state = handle_Connected();  break;
   }
-
-  sendPropertiesToCloud();
-  execCloudEventCallback(ArduinoIoTCloudEvent::SYNC);
+  _state = next_state;
 }
 
 void ArduinoIoTCloudLPWAN::printDebugInfo()
@@ -106,23 +92,57 @@ void ArduinoIoTCloudLPWAN::printDebugInfo()
 }
 
 /******************************************************************************
- * PROTECTED MEMBER FUNCTIONS
+ * PRIVATE MEMBER FUNCTIONS
  ******************************************************************************/
 
-int ArduinoIoTCloudLPWAN::connect()
+ArduinoIoTCloudLPWAN::State ArduinoIoTCloudLPWAN::handle_ConnectPhy()
 {
-  _connection->connect();
-  return 1;
+  if (_connection->check() == NetworkConnectionState::CONNECTED)
+    return State::SyncTime;
+  else
+    return State::ConnectPhy;
 }
 
-void ArduinoIoTCloudLPWAN::disconnect()
+ArduinoIoTCloudLPWAN::State ArduinoIoTCloudLPWAN::handle_SyncTime()
 {
-  _connection->disconnect();
+  unsigned long const internal_posix_time = _time_service.getTime();
+  DBG_VERBOSE("ArduinoIoTCloudLPWAN::%s internal clock configured to posix timestamp %d", __FUNCTION__, internal_posix_time);
+  return State::Connected;
 }
 
-/******************************************************************************
- * PRIVATE MEMBER FUNCTIONS
- ******************************************************************************/
+ArduinoIoTCloudLPWAN::State ArduinoIoTCloudLPWAN::handle_Connected()
+{
+  if (!connected())
+  {
+    DBG_ERROR("ArduinoIoTCloudLPWAN::%s connection to gateway lost", __FUNCTION__);
+    return State::ConnectPhy;
+  }
+
+  /* Check if a primitive property wrapper is locally changed. */
+  updateTimestampOnLocallyChangedProperties(_property_container);
+  
+  /* Decode available data. */
+  if (_connection->available())
+    decodePropertiesFromCloud();
+
+  /* If properties need updating sent them to the cloud. */
+  sendPropertiesToCloud();
+
+  return State::Connected;
+}
+
+void ArduinoIoTCloudLPWAN::decodePropertiesFromCloud()
+{
+  uint8_t lora_msg_buf[CBOR_LORA_MSG_MAX_SIZE];
+  size_t bytes_received;
+  for (bytes_received = 0;
+       _connection->available() && (bytes_received < CBOR_LORA_MSG_MAX_SIZE);
+       bytes_received++)
+  {
+    lora_msg_buf[bytes_received] = _connection->read();
+  }
+  CBORDecoder::decode(_property_container, lora_msg_buf, bytes_received);
+}
 
 void ArduinoIoTCloudLPWAN::sendPropertiesToCloud()
 {

src/ArduinoIoTCloudLPWAN.h

@@ -50,18 +50,25 @@ class ArduinoIoTCloudLPWAN : public ArduinoIoTCloudClass
     inline void setIntervalRetry(long val) { _intervalRetry = val; }
 
 
-  protected:
-
-    virtual int  connect       () override;
-    virtual void disconnect    () override;
-
-
   private:
 
+    enum class State
+    {
+      ConnectPhy,
+      SyncTime,
+      Connected,
+    };
+
+    State _state;
     bool _retryEnable;
     int _maxNumRetry;
     long _intervalRetry;
 
+    State handle_ConnectPhy();
+    State handle_SyncTime();
+    State handle_Connected();
+
+    void decodePropertiesFromCloud();
     void sendPropertiesToCloud();
     int writeProperties(const byte data[], int length);
 };