M5 ATOM(ESP32)でWiFiに常時接続してHTTP POSTするやつ

main.cpp

#define FASTLED_INTERNAL

#include <Arduino.h>
#include <WiFi.h>
#include <HttpClient.h>
#include <FastLED.h>
#include <ArduinoJson.h>

const int NUM_LEDS = 1;
const int LED_PIN = 27;
static CRGB leds[NUM_LEDS];

const int BUTTON_PIN = 39;
bool BUTTON_STATE = false;

void setup() {
  // LED
  FastLED.addLeds<WS2812, LED_PIN, GRB>(leds, NUM_LEDS);
  FastLED.setBrightness(1);
  leds[0] = CRGB::Black;
  FastLED.show();

  // Button
  pinMode(BUTTON_PIN, INPUT_PULLUP);

  // Serial
  Serial.begin(115200);
  Serial.flush();

  Serial.println("");
}

void post(const char* content) {
  DynamicJsonDocument doc(JSON_OBJECT_SIZE(2));
  doc["title"] = "ATOM Lite Wifi Test";
  doc["content"] = content;
  String json;
  serializeJson(doc, json);

  HTTPClient http;
  http.begin("http://httpbin.org/post");
  http.addHeader("Content-Type", "application/json");
  http.POST(json);
  Serial.println(http.getString());
  http.end();
}

void loop() {
  if (WiFi.status() == WL_CONNECTED) {
    if (digitalRead(BUTTON_PIN) == LOW && !BUTTON_STATE) {
      post("The button was pressed.");
      BUTTON_STATE = true;
    } else if (digitalRead(BUTTON_PIN) == HIGH && BUTTON_STATE) {
      BUTTON_STATE = false;
    }
  } else {
    leds[0] = CRGB::Red;
    FastLED.show();
    WiFi.begin(WIFI_SSID, WIFI_PASS);
    int wifiReconnectCount = 0;
    while (WiFi.status() != WL_CONNECTED) {
      if (wifiReconnectCount >= 200) { ESP.restart(); }
      wifiReconnectCount++;
      delay(100);
    }
    post("It's now online.");
    leds[0] = CRGB::Green;
    FastLED.show();
  }
}

platformio.ini

; PlatformIO Project Configuration File
;
;   Build options: build flags, source filter
;   Upload options: custom upload port, speed and extra flags
;   Library options: dependencies, extra library storages
;   Advanced options: extra scripting
;
; Please visit documentation for the other options and examples
; https://docs.platformio.org/page/projectconf.html

[env:m5stick-c]
platform = espressif32
board = m5stick-c
framework = arduino
monitor_speed = 115200
lib_deps =
	bblanchon/ArduinoJson@^6.17.2
	fastled/FastLED@^3.3.3
build_flags =
	-D WIFI_SSID='"${sysenv.WIFI_SSID}"'
	-D WIFI_PASS='"${sysenv.WIFI_PASS}"'

setenv.ps1

$env:WIFI_SSID = "**********"
$env:WIFI_PASS = "**********"