Encapsulate provision of time within one single object

src/ArduinoIoTCloudTCP.cpp

@@ -18,16 +18,14 @@
 
 #ifdef HAS_TCP
 #include <ArduinoIoTCloudTCP.h>
+#include "utility/time/TimeService.h"
 #ifdef BOARD_HAS_ECCX08
   #include "utility/ECCX08Cert.h"
   #include "utility/BearSSLTrustAnchor.h"
   #include <ArduinoECCX08.h>
 #endif
 
-#ifdef ARDUINO_ARCH_SAMD
-  #include <RTCZero.h>
-  RTCZero rtc;
-#endif
+TimeService time_service;
 
 #ifdef BOARD_HAS_ECCX08
   const static int keySlot									                 = 0;
@@ -41,20 +39,7 @@ const static int CONNECT_FAILURE							               = 0;
 const static int CONNECT_FAILURE_SUBSCRIBE					         = -1;
 
 static unsigned long getTime() {
-  if (!ArduinoCloud.getConnection()) {
-    return 0;
-  }
-  TcpIpConnectionHandler * connection = ArduinoCloud.getConnection();
-  unsigned long time = connection->getTime();
-  Debug.print(DBG_DEBUG, "NTP time: %lu", time);
-  if (!NTPUtils::isTimeValid(time)) {
-    Debug.print(DBG_ERROR, "Bogus NTP time from API, fallback to UDP method");
-    time = NTPUtils(connection->getUDP()).getTime();
-  }
-  #ifdef ARDUINO_ARCH_SAMD
-  rtc.setEpoch(time);
-  #endif
-  return time;
+  return time_service.getTime();
 }
 
 ArduinoIoTCloudTCP::ArduinoIoTCloudTCP():
@@ -92,9 +77,7 @@ int ArduinoIoTCloudTCP::begin(TcpIpConnectionHandler & connection, String broker
   _connection = &connection;
   _brokerAddress = brokerAddress;
   _brokerPort = brokerPort;
-  #ifdef ARDUINO_ARCH_SAMD
-  rtc.begin();
-  #endif
+  time_service.begin(&connection);
   return begin(_connection->getClient(), _brokerAddress, _brokerPort);
 }
 

src/ArduinoIoTCloudTCP.h

@@ -30,8 +30,6 @@
 
 #include <ArduinoMqttClient.h>
 
-#include "utility/NTPUtils.h"
-
 
 static char const DEFAULT_BROKER_ADDRESS_SECURE_AUTH[] = "mqtts-sa.iot.arduino.cc";
 static uint16_t const DEFAULT_BROKER_PORT_SECURE_AUTH = 8883;

src/utility/time/NTPUtils.cpp

@@ -0,0 +1,86 @@
+/*
+   This file is part of ArduinoIoTCloud.
+
+   Copyright 2020 ARDUINO SA (http://www.arduino.cc/)
+
+   This software is released under the GNU General Public License version 3,
+   which covers the main part of arduino-cli.
+   The terms of this license can be found at:
+   https://www.gnu.org/licenses/gpl-3.0.en.html
+
+   You can be released from the requirements of the above licenses by purchasing
+   a commercial license. Buying such a license is mandatory if you want to modify or
+   otherwise use the software for commercial activities involving the Arduino
+   software without disclosing the source code of your own applications. To purchase
+   a commercial license, send an email to [email protected].
+*/
+
+/**************************************************************************************
+ * INCLUDE
+ **************************************************************************************/
+
+#include "../../ArduinoIoTCloud_Defines.h"
+#ifndef HAS_LORA
+
+#include "NTPUtils.h"
+
+#include <Arduino.h>
+
+/**************************************************************************************
+ * PUBLIC MEMBER FUNCTIONS
+ **************************************************************************************/
+
+unsigned long NTPUtils::getTime(UDP & udp)
+{
+  udp.begin(NTP_LOCAL_PORT);
+
+  sendNTPpacket(udp);
+
+  bool is_timeout = false;
+  unsigned long const start = millis();
+  do
+  {
+    is_timeout = (millis() - start) >= NTP_TIMEOUT_MS;
+  } while(!is_timeout && !udp.parsePacket());
+
+  if(is_timeout) {
+    udp.stop();
+    return 0;
+  }
+
+  uint8_t ntp_packet_buf[NTP_PACKET_SIZE];
+  udp.read(ntp_packet_buf, NTP_PACKET_SIZE);
+  udp.stop();
+
+  unsigned long const highWord      = word(ntp_packet_buf[40], ntp_packet_buf[41]);
+  unsigned long const lowWord       = word(ntp_packet_buf[42], ntp_packet_buf[43]);
+  unsigned long const secsSince1900 = highWord << 16 | lowWord;
+  unsigned long const seventyYears  = 2208988800UL;
+  unsigned long const epoch         = secsSince1900 - seventyYears;
+
+  return epoch;
+}
+
+/**************************************************************************************
+ * PRIVATE MEMBER FUNCTIONS
+ **************************************************************************************/
+
+void NTPUtils::sendNTPpacket(UDP & udp)
+{
+  uint8_t ntp_packet_buf[NTP_PACKET_SIZE] = {0};
+
+  ntp_packet_buf[0]  = 0b11100011;
+  ntp_packet_buf[1]  = 0;
+  ntp_packet_buf[2]  = 6;
+  ntp_packet_buf[3]  = 0xEC;
+  ntp_packet_buf[12] = 49;
+  ntp_packet_buf[13] = 0x4E;
+  ntp_packet_buf[14] = 49;
+  ntp_packet_buf[15] = 52;
+
+  udp.beginPacket(NTP_TIME_SERVER, NTP_TIME_SERVER_PORT);
+  udp.write(ntp_packet_buf, NTP_PACKET_SIZE);
+  udp.endPacket();
+}
+
+#endif /* #ifndef HAS_LORA */

src/utility/time/NTPUtils.h

@@ -0,0 +1,59 @@
+/*
+   This file is part of ArduinoIoTCloud.
+
+   Copyright 2020 ARDUINO SA (http://www.arduino.cc/)
+
+   This software is released under the GNU General Public License version 3,
+   which covers the main part of arduino-cli.
+   The terms of this license can be found at:
+   https://www.gnu.org/licenses/gpl-3.0.en.html
+
+   You can be released from the requirements of the above licenses by purchasing
+   a commercial license. Buying such a license is mandatory if you want to modify or
+   otherwise use the software for commercial activities involving the Arduino
+   software without disclosing the source code of your own applications. To purchase
+   a commercial license, send an email to [email protected].
+*/
+
+#ifndef __NTP_UTILS__
+#define __NTP_UTILS__
+
+#include "../../ArduinoIoTCloud_Defines.h"
+#ifndef HAS_LORA
+
+/*
+	This Utility Class is derived from the example code found here https://www.arduino.cc/en/Tutorial/UdpNTPClient
+	For more information on NTP (Network Time Protocol) you can refer to this Wikipedia article https://en.wikipedia.org/wiki/Network_Time_Protocol
+*/
+
+/**************************************************************************************
+ * INCLUDE
+ **************************************************************************************/
+
+#include <Udp.h>
+
+/**************************************************************************************
+ * CLASS DECLARATION
+ **************************************************************************************/
+
+class NTPUtils
+{
+public:
+
+  static unsigned long getTime(UDP & udp);
+
+private:
+
+  static size_t        const NTP_PACKET_SIZE      = 48;
+  static int           const NTP_TIME_SERVER_PORT = 123;
+  static int           const NTP_LOCAL_PORT       = 8888;
+  static unsigned long const NTP_TIMEOUT_MS       = 1000;
+  static char constexpr *    NTP_TIME_SERVER      = "time.arduino.cc";
+
+  static void sendNTPpacket(UDP & udp);
+
+};
+
+#endif /* #ifndef HAS_LORA */
+
+#endif