Added ConnectionManager (experimental WIP)

Author: cmaglie

src/ArduinoIoTCloud.cpp

@@ -8,6 +8,13 @@ const static int compressedCertSlot                        = 10;
 const static int serialNumberAndAuthorityKeyIdentifierSlot = 11;
 const static int thingIdSlot                               = 12;
 
+static ConnectionManager *getTimeConnection = NULL;
+
+static unsigned long getTime() {
+  if (!getTimeConnection) return 0;
+  return getTimeConnection->getTime();
+}
+
 ArduinoIoTCloudClass::ArduinoIoTCloudClass() :
   _thing_id     (""),
   _bearSslClient(NULL),
@@ -28,8 +35,10 @@ ArduinoIoTCloudClass::~ArduinoIoTCloudClass()
   }
 }
 
-int ArduinoIoTCloudClass::begin(Client& net, String brokerAddress)
+int ArduinoIoTCloudClass::begin(ConnectionManager *c, String brokerAddress)
 {
+  connection = c;
+
   // store the broker address as class member
   _brokerAddress = brokerAddress;
 
@@ -61,10 +70,15 @@ int ArduinoIoTCloudClass::begin(Client& net, String brokerAddress)
   if (_bearSslClient) {
     delete _bearSslClient;
   }
-  _bearSslClient = new BearSSLClient(net);
+  _bearSslClient = new BearSSLClient(connection->getClient());
   _bearSslClient->setEccSlot(keySlot, ECCX08Cert.bytes(), ECCX08Cert.length());
   _mqttClient = new MqttClient(*_bearSslClient);
 
+  // Bind ArduinoBearSSL callback using static "non-method" function
+  getTimeConnection = connection;
+  ArduinoBearSSL.onGetTime(getTime);
+  // TODO: Find a better way to allow callback into object method
+
   // Begin function for the MQTTClient
   mqttClientBegin();
 
@@ -134,7 +148,7 @@ bool ArduinoIoTCloudClass::mqttReconnect(int const maxRetries, int const timeout
 
   // Check for MQTT broker connection, of if maxReties limit is reached
   // if MQTTClient is connected , simply do nothing and retun true
-  while(!_mqttClient->connected() && (retries++ < maxRetries) && (millis() - start < timeout)) {
+  while (!_mqttClient->connected() && (retries++ < maxRetries) && (millis() - start < timeout)) {
     // int connectError = _mqttClient->connectError();
 
     // try establish the MQTT broker connection
@@ -179,11 +193,6 @@ int ArduinoIoTCloudClass::reconnect(Client& /*net*/)
   return connect();
 }
 
-void ArduinoIoTCloudClass::onGetTime(unsigned long(*callback)(void))
-{
-  ArduinoBearSSL.onGetTime(callback);
-}
-
 int ArduinoIoTCloudClass::connected()
 {
   return _mqttClient->connected();

src/ArduinoIoTCloud.h

@@ -4,6 +4,7 @@
 #include <ArduinoMqttClient.h>
 #include <ArduinoIoTCloudBearSSL.h>
 #include <ArduinoCloudThing.h>
+#include "ConnectionManager.h"
 
 #include "CloudSerial.h"
 
@@ -20,13 +21,15 @@ typedef struct {
   int timeout;
 } mqttConnectionOptions;
 
+extern ConnectionManager *ArduinoIoTPreferredConnection;
+
 class ArduinoIoTCloudClass {
 
 public:
   ArduinoIoTCloudClass();
   ~ArduinoIoTCloudClass();
 
-  int begin(Client& net, String brokerAddress = "mqtts-sa.iot.arduino.cc");
+  int begin(ConnectionManager *connection = ArduinoIoTPreferredConnection, String brokerAddress = "mqtts-sa.iot.arduino.cc");
 
   // Class constant declaration
   static const int MQTT_TRANSMIT_BUFFER_SIZE = 256;
@@ -41,9 +44,6 @@ class ArduinoIoTCloudClass {
 
   // defined for users who want to specify max reconnections reties and timeout between them
   void update(int const reconnectionMaxRetries, int const reconnectionTimeoutMs);
-  // It must be a user defined function, in order to avoid ArduinoCloud include specific WiFi file
-  // in this case this library is independent from the WiFi one
-  void onGetTime(unsigned long(*)(void));
 
   int connected();
   // Clean up existing Mqtt connection, create a new one and initialize it
@@ -88,6 +88,7 @@ class ArduinoIoTCloudClass {
   bool mqttReconnect(int const maxRetries, int const timeout);
 
 private:
+  ConnectionManager *connection;
   static void onMessage(int length);
   void handleMessage(int length);
 

src/ConnectionManager.h

@@ -0,0 +1,85 @@
+#ifndef CONNECTION_MANAGER_H_INCLUDED
+#define CONNECTION_MANAGER_H_INCLUDED
+
+#include <Client.h>
+
+/* NOT USED FOR NOW */
+enum ArduinoIoTConnectionStatus {
+  IOT_STATUS_IDLE,/* only at start */
+  IOT_STATUS_CLOUD_IDLE,
+  IOT_STATUS_CLOUD_CONNECTING,
+  IOT_STATUS_CLOUD_CONNECTED,
+  IOT_STATUS_CLOUD_DISCONNECTED,
+  IOT_STATUS_CLOUD_ERROR,
+  IOT_STATUS_NETWORK_IDLE,
+  IOT_STATUS_NETWORK_CONNECTED,
+  IOT_STATUS_NETWORK_CONNECTING,
+  IOT_STATUS_NETWORK_DISCONNECTED,
+  IOT_STATUS_NETWORK_ERROR,
+  IOT_STATUS_ERROR_GENERIC
+};
+
+class ConnectionManager {
+public:
+  virtual void init() = 0;
+  virtual void check() = 0;
+  virtual ArduinoIoTConnectionStatus status() = 0;
+  virtual unsigned long getTime() = 0;
+  virtual Client &getClient();
+};
+
+// ********* NETWORK LAYER **********
+// max network layer connection retries
+#define NETWORK_LAYER_CONNECTION_RETRIES 6
+// ms to wait between each retry
+#define NETWORK_LAYER_CONNECTION_TIMEOUT 10000
+// ms to wait between each retry
+#define NETWORK_LAYER_RECONNECTION_TIMEOUT 2000
+
+// ********** CLOUD LAYER *********** 
+// max arduino cloud connection retries
+#define ARDUINO_IOT_CLOUD_CONNECTION_RETRIES 30
+// max wifi connection retries
+#define ARDUINO_IOT_CLOUD_CONNECTION_TIMEOUT 3000
+
+// Network Connection Status
+//int iotStatus = IOT_STATUS_IDLE;   
+//int networkStatus = NETWORK_IDLE_STATUS;
+
+// === NETWORK CONNECTION MANAGEMENT ===
+// last time when the Network Connection was checked
+//unsigned long lastNetworkCheck = 0;
+// time interval to check the Network Connection
+//static const unsigned long NETWORK_CONNECTION_INTERVAL = 30000;
+// timeout between each network connection retry
+//static const unsigned long NETWORK_CONNECTION_TIMEOUT = 2000;
+
+#ifdef ARDUINO_SAMD_MKR1000
+#include <WiFi101.h>
+#include "WiFiConnectionManager.h"
+#define BOARD_HAS_WIFI
+#define NETWORK_HARDWARE_ERROR WL_NO_SHIELD
+#define NETWORK_IDLE_STATUS WL_IDLE_STATUS
+#define NETWORK_CONNECTED WL_CONNECTED
+#endif
+
+#ifdef ARDUINO_SAMD_MKRWIFI1010
+#include <WiFiNINA.h>
+#include "WiFiConnectionManager.h"
+#define BOARD_HAS_WIFI
+#define NETWORK_HARDWARE_ERROR WL_NO_MODULE
+#define NETWORK_IDLE_STATUS WL_IDLE_STATUS
+#define NETWORK_CONNECTED WL_CONNECTED
+#endif
+
+#ifdef ARDUINO_SAMD_MKRGSM1400
+#include <MKRGSM.h>
+#define BOARD_HAS_GSM
+#define NETWORK_HARDWARE_ERROR GPRS_PING_ERROR
+#define NETWORK_IDLE_STATUS GSM3_NetworkStatus_t::IDLE
+#define NETWORK_CONNECTED GSM3_NetworkStatus_t::GPRS_READY
+#endif
+
+#include <ArduinoIoTCloud.h>
+
+#endif

src/GSMConnectionManager.h

@@ -0,0 +1,59 @@
+#include <MKRGSM.h>
+#include "ConnectionManager.h"
+
+class GSMConnectionManager : public ConnectionManager {
+public:
+  GSMConnectionManager(const char *pin, const char *apn, const char *login, const char *pass);
+
+  virtual unsigned long getTime();
+  virtual void init();
+  virtual void check();
+  virtual Client &getClient() { return networkClient; };
+  virtual ArduinoIoTConnectionStatus status() { return IOT_STATUS_IDLE; };
+
+  GSMClient networkClient;
+  GSM gsmAccess;
+  GPRS gprs;
+private:
+  const char *pin, *apn, *login, *pass;
+  unsigned long lastNetworkCheck, lastNetworkStep;
+};
+
+static const unsigned long NETWORK_CONNECTION_INTERVAL = 30000;
+
+GSMConnectionManager::GSMConnectionManager(const char *pin, const char *apn, const char *login, const char *pass) :
+  pin(pin), apn(apn), login(login), pass(pass), lastNetworkCheck(millis()) {
+}
+
+unsigned long GSMConnectionManager::getTime() {
+  return gsmAccess.getTime();
+}
+
+void GSMConnectionManager::init() {
+  if (gsmAccess.begin(pin) == GSM_READY && gprs.attachGPRS(apn, login, pass) == GPRS_READY) {
+    Serial.println("GPRS connected");
+    int pingResult = gprs.ping("google.com");
+    if (pingResult >= 0) {
+      Serial.print("SUCCESS! RTT = ");
+      Serial.print(pingResult);
+      Serial.println(" ms");
+    }
+  } else {
+    Serial.println("GPRS not connected");
+    while(1);
+  }
+}
+
+void GSMConnectionManager::check() {
+  if (millis() - lastNetworkCheck < NETWORK_CONNECTION_INTERVAL) {
+    return;
+  }
+
+  Serial.print("<<Network Status: ");
+  if (gprs.attachGPRS(apn, login, pass) == GPRS_READY) {
+    Serial.println("CONNECTED");
+    lastNetworkCheck = millis();
+  } else {
+    Serial.println("NOT CONNECTED");
+  }
+}

src/WiFiConnectionManager.h

@@ -0,0 +1 @@
+// TODO