I`m trying to do POST request to my ssl server, using https. Here is my arduino code example:

#include "recipes/WiFi.h"
#include "Fetch.h"

#define SSID "My_wifi_name"
#define PASSPHRASE "My_wifi_pass"
#define FINGERPRINT "Sha-1 ssl cert from website"

void setup() {
    connectWiFi(SSID, PASSPHRASE);

void loop() {
    RequestOptions options;
    options.method = "POST";
    options.body = "{\"sensor\":\"gps\",\"time\":1351824120,\"data\[48.756080,2.302038]}";
    options.fingerprint = FINGERPRINT;

    Response response = fetch("https://MYSITE.COM/post", options);

    // Printing res ponse.
    // Printing respons headers.
    Serial.printf("Connection Header: \"%s\"\n", response.headers["Content-Type"].c_str());
    Serial.printf("Connection Header: \"%s\"\n", response.headers["Connection"].c_str());

The problem, is that:

enter image description here

Python request with default data {"323": "323"} on server is ok, but my backend founds nothing in arduino request data.

Any ideas, how to fix it? Ty. Custom library GIThub: https://github.com/instanceofMA/arduino-fetch


1 Answer 1


Okay. You need to use at least:

options.headers["Content-Length"] = "LenghtOfYourJson";
options.headers["Content-Type"] = "application/json";

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