HTTP.begin() returns false

Development Tools Cloud IoT
1

Hi. I'm reading DHT11 data and trying to send it to my cloud server using nodeMCU ESP32. The problem is I can not run "http.begin()" line. It always returns false. So far, I've tried adding fingerprint,

const uint8_t fingerprint[20] = "aa bb cc dd";
http.begin(fingerprint, host);

adding WiFiClient,

WiFiClient clientt;
http.begin(clientt, host);

and adding WiFiClientSecure;

 WiFiClientSecure client;
  client.setInsecure(); 
  client.connect(host, 443);
  http.begin(client, host);

but it won't work. Since http.begin() return false, my post request returns -1. Here is my full code:

#include <ESP8266WiFi.h>
#include <WiFiClient.h> 
#include <ESP8266WebServer.h>
#include <ESP8266HTTPClient.h>
#include <DHT.h>
#include <WiFiClientSecureBearSSL.h>


#define DHTTYPE DHT11 


/* Set these to your desired credentials. */
const char *ssid = "ssid";  //ENTER YOUR WIFI SETTINGS
const char *password = "password";
const char *userId = "123";
//Web/Server address to read/write from 
const char *host = 'http://api.iot-ms.xyz/api/devices/data/'+userId;   //website or IP address of server
//DHT pin
const int DHTPin = D4;
DHT dht(DHTPin, DHTTYPE);

static char celsiusTemp[7];
static char fahrenheitTemp[7];
static char humidityTemp[7];

//=======================================================================
//                    Power on setup
//=======================================================================

void setup() {
  delay(1000);
  Serial.begin(115200);
  delay(10);
  dht.begin();
  delay(10);
  WiFi.mode(WIFI_OFF);        //Prevents reconnection issue (taking too long to connect)
  delay(1000);
  WiFi.mode(WIFI_STA);        //This line hides the viewing of ESP as wifi hotspot
  
  WiFi.begin(ssid, password);     //Connect to your WiFi router
  Serial.println("");

  Serial.print("Connecting");
  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  //If connection successful show IP address in serial monitor
  Serial.println("");
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());  //IP address assigned to your ESP
}

//=======================================================================
//                    Main Program Loop
//=======================================================================
void loop() {
  HTTPClient http;    //Declare object of class HTTPClient

  String ADCDataTemp, ADCDataHum, station, postData;
  float temperature = dht.readTemperature();  //Read Analog value of LDR
  float humidity = dht.readHumidity();
  Serial.print("Temperature: ");
  Serial.println(temperature);
  Serial.print("Humidity: ");
  Serial.println(humidity);
  
  if (isnan(humidity) || isnan(temperature)) {
              Serial.println("DHT sensoru okunamadi.");
              strcpy(celsiusTemp,"HATA!");
              strcpy(fahrenheitTemp, "HATA!");
              strcpy(humidityTemp, "HATA!");         
            } 

    //TESTING JSON CREATION
  String json = "{\"mac_address\": \""+WiFi.macAddress()+"\",\"temperature\": \""+temperature+"\",\"humidity\": \""+humidity+ "\"}";
  Serial.println(json);
  Serial.println("MAC Address: "+WiFi.macAddress());
  ADCDataTemp = String(temperature);
  ADCDataHum = String(humidity); //String to interger conversion
  //Post Data
  //const uint8_t fingerprint[20] = {};

  WiFiClient clientt;
  bool isBegin = http.begin(clientt, host);
  if(isBegin){
    http.addHeader("Content-Type", "application/json");    //Specify content-type header
  http.addHeader("Accept","application/json");

  int httpCode = http.POST(json);   //Send the request
  String payload = http.getString();    //Get the response payload
  
  Serial.print("HTTP Code: ");   //Print HTTP return code
  Serial.println(httpCode);
  Serial.print("Request response payload: ");    //Print request response payload
  Serial.println(payload);
  }else{
    Serial.println("HTTP begin failed!");
  }
  

  http.end();  //Close connection
  
  delay(5000);  //Post Data at every 5 seconds
}

And this is my output:

01:35:43.596 -> .........
01:35:48.310 -> Connected to WiFi
01:35:48.667 -> Temperature: 25.50
01:35:48.667 -> Humidity: 51.00
01:35:48.667 -> HTTP begin failed!
01:35:53.357 -> Temperature: 25.60
01:35:53.357 -> Humidity: 51.00
01:35:53.402 -> HTTP begin failed!
01:35:58.410 -> Temperature: 25.60
01:35:58.410 -> Humidity: 51.00
01:35:58.410 -> HTTP begin failed!
01:36:03.454 -> Temperature: 25.70
01:36:03.454 -> Humidity: 51.00
01:36:03.454 -> HTTP begin failed!

I've checked my server url and I validated my json object. I have tried both http and https in my server url. Can you please help me? Thanks in advance...

2

Is there meant to be a double tt in your client code?

WiFiClient clientt;
http.begin(clientt, host);

WiFiClient clientt;
  bool isBegin = http.begin(clientt, host);
3

Yes sir. I’m not very used to C. If i type client, it’s color would turn to orange. So I decided to guarantee I’m not referring to something else.

4

Hi.

Have you ever figured out how to make this work? I am just getting into ESP32 and DHT11 and have encountered the same issue.

Thank you.

5

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