Check internet availability

.github/workflows/compile-examples.yml

@@ -38,6 +38,7 @@ jobs:
         - name: Blues Wireless Notecard
       SKETCH_PATHS: |
         - examples/ConnectionHandlerDemo
+        - examples/CheckInternetAvailabilityDemo
       ARDUINOCORE_MBED_STAGING_PATH: extras/ArduinoCore-mbed
       ARDUINOCORE_API_STAGING_PATH: extras/ArduinoCore-API
       SKETCHES_REPORTS_PATH: sketches-reports

examples/CheckInternetAvailabilityDemo/CheckInternetAvailabilityDemo.ino

@@ -0,0 +1,152 @@
+/* SECRET_ fields are in `arduino_secrets.h` (included below)
+ *
+ * If using a WiFi board (Arduino MKR1000, MKR WiFi 1010, Nano 33 IoT, UNO
+ * WiFi Rev 2 or ESP8266/32), create a WiFiConnectionHandler object by adding
+ * Network Name (SECRET_WIFI_SSID) and password (SECRET_WIFI_PASS) in the
+ * arduino_secrets.h file (or Secrets tab in Create Web Editor).
+ *
+ *    WiFiConnectionHandler conMan(SECRET_WIFI_SSID, SECRET_WIFI_PASS);
+ *
+ * If using a MKR GSM 1400 or other GSM boards supporting the same API you'll
+ * need a GSMConnectionHandler object as follows
+ *
+ *    GSMConnectionHandler conMan(SECRET_PIN, SECRET_APN, SECRET_GSM_USER, SECRET_GSM_PASS);
+ *
+ * If using a MKR NB1500 you'll need a NBConnectionHandler object as follows
+ *
+ *    NBConnectionHandler conMan(SECRET_PIN);
+ *
+ * If using a Portenta + Ethernet shield you'll need a EthernetConnectionHandler object as follows:
+ *
+ * DHCP mode
+ *    EthernetConnectionHandler conMan;
+ *
+ * Manual configuration
+ *    EthernetConnectionHandler conMan(SECRET_IP, SECRET_DNS, SECRET_GATEWAY, SECRET_NETMASK);
+ *
+ * Manual configuration will fallback on DHCP mode if SECRET_IP is invalid or equal to INADDR_NONE.
+ *
+ * This sketch enables the ConnectionHandler to check for internet availability (only for IP based connectivity)
+ * before reporting the Connected state. By default the check is disabled.
+ *
+ */
+
+#include <Arduino_ConnectionHandler.h>
+
+#include "arduino_secrets.h"
+
+#define CONN_TOGGLE_MS 60000
+
+#if !(defined(BOARD_HAS_WIFI) || defined(BOARD_HAS_GSM) || defined(BOARD_HAS_LORA) || \
+      defined(BOARD_HAS_NB) || defined(BOARD_HAS_ETHERNET) || defined(BOARD_HAS_CATM1_NBIOT))
+  #error "Please check Arduino Connection Handler supported boards list: https://github.com/arduino-libraries/Arduino_ConnectionHandler/blob/master/README.md"
+#endif
+
+#if defined(BOARD_HAS_ETHERNET)
+EthernetConnectionHandler conMan(SECRET_IP, SECRET_DNS, SECRET_GATEWAY, SECRET_NETMASK);
+#elif defined(BOARD_HAS_WIFI)
+WiFiConnectionHandler conMan(SECRET_WIFI_SSID, SECRET_WIFI_PASS);
+#elif defined(BOARD_HAS_GSM)
+GSMConnectionHandler conMan(SECRET_PIN, SECRET_APN, SECRET_GSM_USER, SECRET_GSM_PASS);
+#elif defined(BOARD_HAS_NB)
+NBConnectionHandler conMan(SECRET_PIN);
+#elif defined(BOARD_HAS_LORA)
+LoRaConnectionHandler conMan(SECRET_APP_EUI, SECRET_APP_KEY);
+#elif defined(BOARD_HAS_CATM1_NBIOT)
+CatM1ConnectionHandler conMan(SECRET_PIN, SECRET_APN, SECRET_GSM_USER, SECRET_GSM_PASS);
+#elif defined(BOARD_HAS_CELLULAR)
+CellularConnectionHandler conMan(SECRET_PIN, SECRET_APN, SECRET_GSM_USER, SECRET_GSM_PASS);
+#endif
+
+bool attemptConnect = false;
+uint32_t lastConnToggleMs = 0;
+
+void setup() {
+  /* Initialize serial debug port and wait up to 5 seconds for port to open */
+  Serial.begin(9600);
+  for(unsigned long const serialBeginTime = millis(); !Serial && (millis() - serialBeginTime <= 5000); ) { }
+
+#ifndef __AVR__
+  /* Set the debug message level:
+   * - DBG_ERROR: Only show error messages
+   * - DBG_WARNING: Show warning and error messages
+   * - DBG_INFO: Show info, warning, and error messages
+   * - DBG_DEBUG: Show debug, info, warning, and error messages
+   * - DBG_VERBOSE: Show all messages
+   */
+  setDebugMessageLevel(DBG_INFO);
+#endif
+  /* Enable the connection handler to check for internet availability.
+   * By default is disabled.
+   */
+  conMan.enableCheckInternetAvailability(true);
+  /* Add callbacks to the ConnectionHandler object to get notified of network
+   * connection events. */
+  conMan.addCallback(NetworkConnectionEvent::CONNECTED, onNetworkConnect);
+  conMan.addCallback(NetworkConnectionEvent::DISCONNECTED, onNetworkDisconnect);
+  conMan.addCallback(NetworkConnectionEvent::ERROR, onNetworkError);
+
+  Serial.print("Network Adapter Interface: ");
+  switch (conMan.getInterface()) {
+    case NetworkAdapter::WIFI:
+      Serial.println("Wi-Fi");
+      break;
+    case NetworkAdapter::ETHERNET:
+      Serial.println("Ethernet");
+      break;
+    case NetworkAdapter::NB:
+      Serial.println("Narrowband");
+      break;
+    case NetworkAdapter::GSM:
+      Serial.println("GSM");
+      break;
+    case NetworkAdapter::LORA:
+      Serial.println("LoRa");
+      break;
+    case NetworkAdapter::CATM1:
+      Serial.println("Category M1");
+      break;
+    case NetworkAdapter::CELL:
+      Serial.println("Cellular");
+      break;
+    default:
+      Serial.println("Unknown");
+      break;
+  }
+}
+
+void loop() {
+  /* Toggle the connection every `CONN_TOGGLE_MS` milliseconds */
+  if ((millis() - lastConnToggleMs) > CONN_TOGGLE_MS) {
+    Serial.println("Toggling connection...");
+    if (attemptConnect) {
+      conMan.connect();
+    } else {
+      conMan.disconnect();
+    }
+    attemptConnect = !attemptConnect;
+    lastConnToggleMs = millis();
+  }
+
+  /* The following code keeps on running connection workflows on our
+   * ConnectionHandler object, hence allowing reconnection in case of failure
+   * and notification of connect/disconnect event if enabled (see
+   * addConnectCallback/addDisconnectCallback) NOTE: any use of delay() within
+   * the loop or methods called from it will delay the execution of .update(),
+   * which might not guarantee the correct functioning of the ConnectionHandler
+   * object.
+   */
+  conMan.check();
+}
+
+void onNetworkConnect() {
+  Serial.println(">>>> CONNECTED to network");
+}
+
+void onNetworkDisconnect() {
+  Serial.println(">>>> DISCONNECTED from network");
+}
+
+void onNetworkError() {
+  Serial.println(">>>> ERROR");
+}

examples/CheckInternetAvailabilityDemo/arduino_secrets.h

@@ -0,0 +1,19 @@
+// Required for WiFiConnectionHandler
+const char SECRET_WIFI_SSID[] = "NETWORK NAME";
+const char SECRET_WIFI_PASS[] = "NETWORK PASSWORD";
+
+// Required for GSMConnectionHandler
+const char SECRET_APN[]       = "MOBILE PROVIDER APN ADDRESS";
+const char SECRET_PIN[]       = "0000";  // Required for NBConnectionHandler
+const char SECRET_GSM_USER[]  = "GSM USERNAME";
+const char SECRET_GSM_PASS[]  = "GSM PASSWORD";
+
+// Required for LoRaConnectionHandler
+const char SECRET_APP_EUI[]  = "APP_EUI";
+const char SECRET_APP_KEY[]  = "APP_KEY";
+
+// Required for EthernetConnectionHandler (without DHCP mode)
+const char SECRET_IP[]       = "IP ADDRESS";
+const char SECRET_DNS[]      = "DNS ADDRESS";
+const char SECRET_GATEWAY[]  = "GATEWAY ADDRESS";
+const char SECRET_NETMASK[]  = "NETWORK MASK";

src/CatM1ConnectionHandler.cpp

@@ -64,11 +64,7 @@ NetworkConnectionState CatM1ConnectionHandler::update_handleInit()
   pinMode(ON_MKR2, OUTPUT);
   digitalWrite(ON_MKR2, HIGH);
 #endif
-  return NetworkConnectionState::CONNECTING;
-}
 
-NetworkConnectionState CatM1ConnectionHandler::update_handleConnecting()
-{
   if(!GSM.begin(
     _settings.catm1.pin,
     _settings.catm1.apn,
@@ -80,8 +76,33 @@ NetworkConnectionState CatM1ConnectionHandler::update_handleConnecting()
     Debug.print(DBG_ERROR, F("The board was not able to register to the network..."));
     return NetworkConnectionState::ERROR;
   }
-  Debug.print(DBG_INFO, F("Connected to Network"));
-  return NetworkConnectionState::CONNECTED;
+  return NetworkConnectionState::CONNECTING;
+}
+
+NetworkConnectionState CatM1ConnectionHandler::update_handleConnecting()
+{
+  if (!GSM.isConnected())
+  {
+    return NetworkConnectionState::INIT;
+  }
+
+  if(!_check_internet_availability){
+    return NetworkConnectionState::CONNECTED;
+  }
+
+  int ping_result = GSM.ping("time.arduino.cc");
+  Debug.print(DBG_INFO, F("GSM.ping(): %d"), ping_result);
+  if (ping_result < 0)
+  {
+    Debug.print(DBG_ERROR, F("Internet check failed"));
+    Debug.print(DBG_INFO, F("Retrying in  \"%d\" milliseconds"), CHECK_INTERVAL_TABLE[static_cast<unsigned int>(NetworkConnectionState::CONNECTING)]);
+    return NetworkConnectionState::CONNECTING;
+  }
+  else
+  {
+    Debug.print(DBG_INFO, F("Connected to Internet"));
+    return NetworkConnectionState::CONNECTED;
+  }
 }
 
 NetworkConnectionState CatM1ConnectionHandler::update_handleConnected()

src/CellularConnectionHandler.cpp

@@ -62,16 +62,31 @@ NetworkConnectionState CellularConnectionHandler::update_handleInit()
     Debug.print(DBG_ERROR, F("SIM not present or wrong PIN"));
     return NetworkConnectionState::ERROR;
   }
-  return NetworkConnectionState::CONNECTING;
-}
 
-NetworkConnectionState CellularConnectionHandler::update_handleConnecting()
-{
   if (!_cellular.connect(String(_settings.cell.apn), String(_settings.cell.login), String(_settings.cell.pass))) {
     Debug.print(DBG_ERROR, F("The board was not able to register to the network..."));
     return NetworkConnectionState::ERROR;
   }
   Debug.print(DBG_INFO, F("Connected to Network"));
+  return NetworkConnectionState::CONNECTING;
+}
+
+NetworkConnectionState CellularConnectionHandler::update_handleConnecting()
+{
+  if (!_cellular.isConnectedToInternet()) {
+    return NetworkConnectionState::INIT;
+  }
+
+  if (!_check_internet_availability) {
+    return NetworkConnectionState::CONNECTED;
+  }
+
+  if(getTime() == 0){
+    Debug.print(DBG_ERROR, F("Internet check failed"));
+    Debug.print(DBG_INFO, F("Retrying in  \"%d\" milliseconds"), CHECK_INTERVAL_TABLE[static_cast<unsigned int>(NetworkConnectionState::CONNECTING)]);
+    return NetworkConnectionState::CONNECTING;
+  }
+
   return NetworkConnectionState::CONNECTED;
 }
 

src/ConnectionHandlerDefinitions.h

@@ -191,12 +191,12 @@ enum class NetworkAdapter {
 
 static unsigned int const CHECK_INTERVAL_TABLE[] =
 {
-  /* INIT          */ 100,
 #if defined(BOARD_HAS_NOTECARD) || defined(ARDUINO_ARCH_ESP8266) || defined(ARDUINO_ARCH_ESP32)
-  /* CONNECTING    */ 4000,
+  /* INIT    */ 4000,
 #else
-  /* CONNECTING    */ 500,
+  /* INIT          */ 500,
 #endif
+  /* CONNECTING    */ 500,
   /* CONNECTED     */ 10000,
   /* DISCONNECTING */ 100,
   /* DISCONNECTED  */ 1000,

src/ConnectionHandlerInterface.cpp

@@ -29,6 +29,7 @@ ConnectionHandler::ConnectionHandler(bool const keep_alive, NetworkAdapter inter
 : _keep_alive{keep_alive}
 , _interface{interface}
 , _lastConnectionTickTime{millis()}
+, _check_internet_availability{false}
 , _current_net_connection_state{NetworkConnectionState::INIT}
 {
 

src/ConnectionHandlerInterface.h

@@ -76,6 +76,9 @@ class ConnectionHandler {
 
     virtual void connect();
     virtual void disconnect();
+    void enableCheckInternetAvailability(bool enable) {
+      _check_internet_availability = enable;
+    }
 
     virtual void addCallback(NetworkConnectionEvent const event, OnNetworkEventCallback callback);
     void addConnectCallback(OnNetworkEventCallback callback) __attribute__((deprecated));
@@ -106,6 +109,7 @@ class ConnectionHandler {
     virtual void updateCallback(NetworkConnectionState next_net_connection_state);
 
     bool _keep_alive;
+    bool _check_internet_availability;
     NetworkAdapter _interface;
 
     virtual NetworkConnectionState update_handleInit         () = 0;

src/EthernetConnectionHandler.cpp

@@ -72,11 +72,6 @@ NetworkConnectionState EthernetConnectionHandler::update_handleInit()
     Debug.print(DBG_ERROR, F("Error, ethernet shield was not found."));
     return NetworkConnectionState::ERROR;
   }
-  return NetworkConnectionState::CONNECTING;
-}
-
-NetworkConnectionState EthernetConnectionHandler::update_handleConnecting()
-{
   IPAddress ip(_settings.eth.ip.type, _settings.eth.ip.bytes);
 
   // An ip address is provided -> static ip configuration
@@ -91,7 +86,7 @@ NetworkConnectionState EthernetConnectionHandler::update_handleConnecting()
       Debug.print(DBG_ERROR, F("Failed to configure Ethernet, check cable connection"));
       Debug.print(DBG_VERBOSE, "timeout: %d, response timeout: %d",
         _settings.eth.timeout, _settings.eth.response_timeout);
-      return NetworkConnectionState::CONNECTING;
+      return NetworkConnectionState::INIT;
     }
   // An ip address is not provided -> dhcp configuration
   } else {
@@ -100,11 +95,37 @@ NetworkConnectionState EthernetConnectionHandler::update_handleConnecting()
       Debug.print(DBG_VERBOSE, "timeout: %d, response timeout: %d",
         _settings.eth.timeout, _settings.eth.response_timeout);
 
-      return NetworkConnectionState::CONNECTING;
+      return NetworkConnectionState::INIT;
     }
   }
 
-  return NetworkConnectionState::CONNECTED;
+  return NetworkConnectionState::CONNECTING;
+}
+
+NetworkConnectionState EthernetConnectionHandler::update_handleConnecting()
+{
+  if (Ethernet.linkStatus() == LinkOFF) {
+    return NetworkConnectionState::INIT;
+  }
+
+  if (!_check_internet_availability) {
+    return NetworkConnectionState::CONNECTED;
+  }
+
+  int ping_result = Ethernet.ping("time.arduino.cc");
+  Debug.print(DBG_INFO, F("Ethernet.ping(): %d"), ping_result);
+  if (ping_result < 0)
+  {
+    Debug.print(DBG_ERROR, F("Internet check failed"));
+    Debug.print(DBG_INFO, F("Retrying in  \"%d\" milliseconds"), CHECK_INTERVAL_TABLE[static_cast<unsigned int>(NetworkConnectionState::CONNECTING)]);
+    return NetworkConnectionState::CONNECTING;
+  }
+  else
+  {
+    Debug.print(DBG_INFO, F("Connected to Internet"));
+    return NetworkConnectionState::CONNECTED;
+  }
+
 }
 
 NetworkConnectionState EthernetConnectionHandler::update_handleConnected()

src/GSMConnectionHandler.cpp

@@ -53,6 +53,8 @@ GSMConnectionHandler::GSMConnectionHandler(const char * pin, const char * apn, c
 : ConnectionHandler{keep_alive, NetworkAdapter::GSM}
 {
   _settings.type = NetworkAdapter::GSM;
+  // To keep the backward compatibility, the user can call enableCheckInternetAvailability(false) for disabling the check
+  _check_internet_availability = true;
   strncpy(_settings.gsm.pin, pin, sizeof(_settings.gsm.pin)-1);
   strncpy(_settings.gsm.apn, apn, sizeof(_settings.gsm.apn)-1);
   strncpy(_settings.gsm.login, login, sizeof(_settings.gsm.login)-1);
@@ -105,6 +107,10 @@ NetworkConnectionState GSMConnectionHandler::update_handleInit()
 
 NetworkConnectionState GSMConnectionHandler::update_handleConnecting()
 {
+  if(!_check_internet_availability){
+    return NetworkConnectionState::CONNECTED;
+  }
+
   Debug.print(DBG_INFO, F("Sending PING to outer space..."));
   int const ping_result = _gprs.ping("time.arduino.cc");
   Debug.print(DBG_INFO, F("GPRS.ping(): %d"), ping_result);

src/GenericConnectionHandler.cpp

@@ -37,6 +37,7 @@ bool GenericConnectionHandler::updateSetting(const models::NetworkSetting& s) {
     if(_ch != nullptr) {
         _interface = s.type;
         _ch->setKeepAlive(_keep_alive);
+        _ch->enableCheckInternetAvailability(_check_internet_availability);
         return _ch->updateSetting(s);
     } else {
         _interface = NetworkAdapter::NONE;