Wio-Terminal/ESP8622/ESP32ボードを共通のスケッチでWorld Time APIを使う(WorldTimeAPI編)

2020/8/3:
初版

board3 HTTP/JSON

board3 HTTP/JSON

概要

Wio-Terminal/ESP8622/ESP32ボードを共通のスケッチでWorld Time APIを使う(WorldTimeAPI編)
本スケッチは、httpアクセスとJSONライブラリを使用してWorldTimeAPIを利用している。
(ホストPCとしてはubuntuを想定している)

外部ライブラリ(platformioの場合)

以下を実行してライブラリをインストールする：

  # JSON lib インストール
  #pio lib install "ArduinoJson"
  pio lib install 64


  

または、platformio.iniに以下を追加する：

  lib_deps =
      # use "ArduinoJson" lib
      64
  

テスト・スケッチ

src/HTTP_JSON.ino

  // select board
  ////#define WIO_TERMINAL
  ////#define ESP8266
  ////#define ESP32
  //------------------

  // 
  // HTTP/JSON access for Wio-Terminal/ESP8266/ESP32
  //

  #ifdef WIO_TERMINAL
  #include <AtWiFi.h>
  #endif
  #ifdef ESP8266
  #include <ESP8266WiFi.h>
  #endif
  #ifdef ESP32
  #include <WiFi.h>
  #endif

  #include <WiFiClientSecure.h>
  #include <ArduinoJson.h>

  #define BODY_SIZE 1024
  char bodyBuff[BODY_SIZE];

  // Allocate the JSON document
  StaticJsonDocument<400> doc; // change size if error happen

  const char* ssid   = "your_ssid";
  const char* passwd = "your_passwd";

  // prototype
  void ConvertUnixTimeToLocalTime(uint64_t unixtime, uint32_t *pyear, uint8_t *pmonth, uint8_t *pday, uint8_t *phour, uint8_t *pminute, uint8_t *psecond);

  char *weekday[] = {"Sun","Mon","Tue","Wed","Thu","Fri","Sat"};
  uint32_t year;
  uint8_t month, day, hour, minu, sec;

  void setup() {
      // Initialize serial port
      Serial.begin(115200);
      while (!Serial) continue;

      Serial.print("Connecting to ");
      Serial.println(ssid);

      WiFi.begin(ssid, passwd);

      while (WiFi.status() != WL_CONNECTED) {
          delay(500);
          Serial.print(".");
      }

      Serial.println("");
      Serial.println("WiFi connected");   
      Serial.println("IP address: ");
      Serial.println(WiFi.localIP());
  }

  bool Http_Get_access(String host, String url, String argument){
      WiFiClient client;
      client.setTimeout(500);

      const int httpPort = 80;
      const char* host2 = host.c_str();
      if (!client.connect(host2, httpPort)) {
          Serial.println("connection failed");
          return false;
      }
      client.print(String("GET ") + url + "?" + argument + " HTTP/1.1\r\n" +
                          "Host: " + host + "\r\n" + 
                          "User-Agent: ESP8266/1.0\r\n" + 
                          "Connection: close\r\n\r\n");
      unsigned long timeout = micros();
      while (client.available() == 0) {
          if ( micros() - timeout  > 5000000) {
              Serial.println(">>> Client Timeout !");
              client.stop();
              return false;
          }
      }

        Serial.println("--- Header ---");
        while (1) { 
          String line = client.readStringUntil('\n');
          Serial.println(line);
          if (line == "\r") {
            break; // end of header
          }
        }

        //Serial.println("--- Body ---");  // for debug
        int bc = 0;
        while (client.available()) {
          bodyBuff[bc] = client.read(); bc++;
        }
        bodyBuff[bc] = 0;
        //Serial.println(bodyBuff); // display body for debug

        return true;
  }

  void loop() {

      String host = "worldtimeapi.org";
      String url = "/api/timezone/Asia/Tokyo";
      String argument = "";

      Http_Get_access( host, url, argument);
      Serial.println("accessed BODY:");
      Serial.println(bodyBuff);

      // Deserialize the JSON document
      DeserializationError errorJson = deserializeJson(doc, bodyBuff);

      const char* abbreviation = doc["abbreviation"];
      const char* client_ip = doc["client_ip"];
      const char* datetime = doc["datetime"];
      long day_of_week = doc["day_of_week"];
      long day_of_year = doc["day_of_year"];
      long raw_offset = doc["raw_offset"];
      const char* timezone = doc["timezone"];
      long unixtime = doc["unixtime"];
      const char* utc_datetime = doc["utc_datetime"];
      const char* utc_offset = doc["utc_offset"];
      long week_number = doc["week_number"];

      Serial.println();
      Serial.printf("Deserialized:\r\n");
      Serial.printf("abbreviation:%s\r\n",abbreviation);
      Serial.printf("client_ip:%s\r\n",client_ip);
      Serial.printf("datetime:%s\r\n",datetime);
      Serial.printf("day_of_week:%d\r\n",day_of_week);
      Serial.printf("day_of_year:%d\r\n",day_of_year);
      Serial.printf("raw_offset:%d\r\n",raw_offset);
      Serial.printf("timezone:%s\r\n",timezone);
      Serial.printf("unixtime:%d\r\n",unixtime);
      Serial.printf("utc_datetime:%s\r\n",utc_datetime);
      Serial.printf("utc_offset:%s\r\n",utc_offset);
      Serial.printf("week_number:%d\r\n",week_number);
      Serial.println();

      // display current clock from unixtime
      Serial.printf("Current Time from unixtime:\r\n");
      ConvertUnixTimeToLocalTime(unixtime, &year, &month, &day, &hour, &minu, &sec);
      Serial.printf("%4d/%02d/%02d(%s): %02d:%02d:%02d\r\n",
         year, month, day, weekday[day_of_week], hour, minu, sec);
      Serial.println();

      // stop
      Serial.println("Done!");
      delay(1000);
      //while(1){
      //}
  }
  //<----------------------------------------------------------
  // Definition of ConvertUnixTimeToLocalTime function
  // derived/forked from http://mrkk.ciao.jp/memorandom/unixtime/unixtime.html
  #define ARRAYSIZE(_arr) (sizeof(_arr) / sizeof(_arr[0]))
  #define TIME_OFFSET 9*60*60
  #define SECONDS_IN_A_DAY    (24*60*60)
  #define EPOCH_DAY       (1969*365L + 1969/4 - 1969/100 + 1969/400 + 306)    //  days from 0000/03/01 to 1970/01/01
  #define UNIX_EPOCH_DAY  EPOCH_DAY
  #define YEAR_ONE        365
  #define YEAR_FOUR       (YEAR_ONE * 4 + 1)  //  it is YEAR_ONE*4+1 so the maximum reminder of day / YEAR_FOUR is YEAR_ONE * 4 and it occurs only on 2/29
  #define YEAR_100        (YEAR_FOUR * 25 - 1)
  #define YEAR_400        (YEAR_100*4 + 1)    //  it is YEAR_100*4+1 so the maximum reminder of day / YEAR_400 is YEAR_100 * 4 and it occurs only on 2/29

  void ConvertUnixTimeToLocalTime(uint64_t unixtime, uint32_t *pyear, uint8_t *pmonth, uint8_t *pday, uint8_t *phour, uint8_t *pminute, uint8_t *psecond) {
      uint32_t unixday;
      uint16_t year = 0;
      uint8_t  leap = 0;
      uint32_t n;
      uint8_t month, day, weekday;
      uint8_t hour, minute, second;
      static const uint16_t monthday[] = { 0,31,61,92,122,153,184,214,245,275,306,337 };

      unixtime += TIME_OFFSET;
      second = unixtime % 60;
      minute = (unixtime / 60) % 60;
      hour = (unixtime / 3600) % 24;

      unixday = (uint32_t)(unixtime / SECONDS_IN_A_DAY);
      weekday = (uint8_t)((unixday + 3) % 7); //  because the unix epoch day is thursday
      unixday += UNIX_EPOCH_DAY;  //  days from 0000/03/01 to 1970/01/01

      year += 400 * (unixday / YEAR_400);
      unixday %= YEAR_400;

      n = unixday / YEAR_100;
      year += n * 100;
      unixday %= YEAR_100;

      if (n == 4){
          leap = 1;
      } else {
          year += 4 * (unixday / YEAR_FOUR);
          unixday %= YEAR_FOUR;

          n = unixday / YEAR_ONE;
          year += n;
          unixday %= YEAR_ONE;
          if (n == 4) {
              leap = 1;
          }
      }
      if (leap != 0) {
          month = 2;
          day = 29;
      }
      else {
          month = (unixday * 5 + 2) / 153;
          day = unixday - monthday[month] + 1;    //  
          month += 3;
          if (month > 12) {
              ++year;
              month -= 12;
          }
      }
      *psecond = second;
      *pminute = minute;
      *phour = hour;
      *pyear = year;
      *pmonth = month;
      *pday = day;
  }
  //>----------------------------------------------------------

  

以下の#defineでボードを切り換えているがボードの種類を設定すると、 システムで設定されている定義が有効になるので特にソースを変更する必要はない。

  #define WIO_TERMINAL
  #define ESP8266
  #define ESP32
  

以下は、自分の環境に応じて変更する：

  const char* ssid   = "your_ssid";
  const char* passwd = "your_passwd";
  

書き込み後に「picocom /dev/ttyACM0 -b115200」または「picocom /dev/ttyUSB0 -b115200」で通信ソフトを起動すると以下のような出力が表示される：

  $ picocom /dev/ttyACM0 -b115200

  Terminal ready

  --- Header ---
  HTTP/1.1 200 OK
  Connection: close
  Access-Control-Allow-Credentials: true
  Access-Control-Allow-Origin: *
  Access-Control-Expose-Headers: 
  Cache-Control: max-age=0, private, must-revalidate
  Content-Length: 345
  Content-Type: application/json; charset=utf-8
  Cross-Origin-Window-Policy: deny
  Date: Mon, 03 Aug 2020 06:39:09 GMT
  Server: Cowboy
  X-Content-Type-Options: nosniff
  X-Download-Options: noopen
  X-Frame-Options: SAMEORIGIN
  X-Permitted-Cross-Domain-Policies: none
  X-Request-Id: c368a196-c927-43e2-b741-c3ab7ce11336
  X-Runtime: 2ms
  X-Xss-Protection: 1; mode=block
  Via: 1.1 vegur

  accessed BODY:
  {"abbreviation":"JST","client_ip":"218.231.243.62","datetime":"2020-08-03T15:39:10.171382+09:00","day_of_week":1,"day_of_year":216,"dst":false,"dst_from":null,"dst_offset":0,"dst_until":null,"raw_offset":32400,"timezone":"Asia/Tokyo","unixtime":1596436750,"utc_datetime":"2020-08-03T06:39:10.171382+00:00","utc_offset":"+09:00","week_number":32}

  Deserialized:
  abbreviation:JST
  client_ip:218.231.243.62
  datetime:2020-08-03T15:39:10.171382+09:00
  day_of_week:1
  day_of_year:216
  raw_offset:32400
  timezone:Asia/Tokyo
  unixtime:1596436750
  utc_datetime:2020-08-03T06:39:10.171382+00:00
  utc_offset:+09:00
  week_number:32

  Current Time from unixtime:
  2020/08/03(Mon): 15:39:10

  Done!
  

出力には、WorldTimeAPIで取得した時刻が出力される。

参考情報

World Time API
Simple JSON/plain-text API to obtain the current time in, and related data about, a timzone.

Wio-Terminal/ESP8622/ESP32ボードを共通のスケッチで動かす(HTTP-ACCESS編)
ESP8266 Arduino CoreでGETアクセス。HTTP/HTTPS＆プロクシを使ったHTTP通信
ESP8266+ArduinoでHTTPS接続

PlatformIO Core (CLI)

以上