ESP8266 Wifi Connect & Ping to Azure-based Logic App URL over HTTPS

wifiLogicAppPing.ino

// WIFI SETUP & LOGIC APP URL 

char ssid[] = "YOUR_WIFI_SSID";
char pass[] = "YOUR_WIFI_PASSWORD";
char logicAppURL[] = "https://YOUR_LOGIC_APP_URL";

// HTTP AND WIFI

// Needed to go here & install board support for ESP8266. https://github.com/gojimmypi/ESP8266-Arduino
// This gave access to the WiFiClientSecureBearSSL client library (which is needed for HTTPS). 
// See install instructions on that GitHub page.
// Also installed h/w support for the TTGO OLED board I have.

#include <ESP8266WiFi.h>
#include <ESP8266WiFiMulti.h>
#include <ESP8266HTTPClient.h>
#include <WiFiClientSecureBearSSL.h>

// OLED INCLUDES

#include <Arduino.h>
#include <U8g2lib.h>      // make sure to add U8g2 library and restart Arduino IDE  
#include <SPI.h>
#include <Wire.h>

#define OLED_SDA  2
#define OLED_SCL 14
#define OLED_RST  4

U8G2_SSD1306_128X32_UNIVISION_F_SW_I2C u8g2(U8G2_R0, OLED_SCL, OLED_SDA , OLED_RST);

ESP8266WiFiMulti WiFiMulti;

void setup()
{
  Serial.begin(115200);
  Serial.println();

  oledInit();
  
  oledPrint("Start...", false);
  delay(500);
  
  oledPrint("Wifi connect ..", false);
  delay(500);

  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFiMulti.addAP(ssid, pass);

  String progress = ".";
  while (WiFiMulti.run() != WL_CONNECTED) {
    delay(500);
    Serial.print(progress);
    oledPrint(progress, false);
    progress = progress + ".";
  }

  oledPrint("Wifi connected", false);
  delay(1000);
  
  Serial.println("Calling HTTP");
  httpGET(logicAppURL);
}

void loop()
{
  delay(10000);
}

void httpGET(String url) {

  std::unique_ptr<BearSSL::WiFiClientSecure>client(new BearSSL::WiFiClientSecure);
  client->setInsecure();

  HTTPClient https;

  Serial.print("[HTTPS] begin...\n");
  oledPrint("[HTTPS] begin", false);
  
  if (https.begin(*client, url)) {  // HTTPS

    Serial.print("[HTTPS] GET...\n");
    oledPrint("[HTTPS] GET...", false);

    // start connection and send HTTP header
    int httpCode = https.GET();
  
    // httpCode will be negative on error
    if (httpCode > 0) {
      // HTTP header has been send and Server response header has been handled
      Serial.printf("[HTTPS] GET... code: %d\n", httpCode);
      oledPrint("[HTTPS] GET " + String(httpCode), false);

      // file found at server
      if (httpCode == HTTP_CODE_OK || httpCode == HTTP_CODE_MOVED_PERMANENTLY) {
        String payload = https.getString();
        Serial.println(payload);
      }
    } else {
      Serial.printf("[HTTPS] GET... failed, error: %s\n", https.errorToString(httpCode).c_str());
      oledPrint("[HTTPS] GET " + String(https.errorToString(httpCode)), false);
    }

    https.end();
  } else {
    Serial.printf("[HTTPS] Unable to connect\n");
    oledPrint("[HTTPS] GET Err", false);
  }
}

void oledInit() {
  Serial.println("OLED Start..");
  u8g2.begin();
  u8g2.setFont(u8g2_font_6x10_tf);
}

void oledPrint(String message, bool frame) {

  char charBuf[15];
  message.toCharArray(charBuf, 25);
  
  u8g2.clearBuffer();
  u8g2.drawStr(10, 25, charBuf);
  if (frame) u8g2.drawRFrame(0,0,128,32,4); // https://github.com/olikraus/u8g2/wiki/u8g2reference#drawrbox
  u8g2.sendBuffer();
}