Odtnhj

The following code gets a server response of -1.

What am I doing wrong? I've done a bunch of research and this is the suggested code.

I've tested the server code with Postman, and it works fine, so it must be the other code.

Library used is ESP8266HTTPClient.h

ESP8266 code

void loop() 
 HTTPClient http;

 http.begin("http://localhost:3003/record");
 http.addHeader("Content-Type", "application/x-www-form-urlencoded");

 int httpCode = http.POST("Message");
 String payload = http.getString();

 Serial.println(httpCode); // -1
 Serial.println(payload); // nothing

 http.end();

Node Express server

var express = require("express");
var router = express.Router();

router.post("/record", function(req, res) 
 let message = req.body;
 console.log(message);

 res.status(200).send(
 message: message
 );
);

module.exports = router;

Also tried a different API, with a GET request. Still doesn't work.

void loop() 
 HTTPClient http;

 http.begin("https://jsonplaceholder.typicode.com/posts/1");
 http.addHeader("Content-Type", "application/x-www-form-urlencoded");

 int httpCode = http.GET();
 String payload = http.getString();

 Serial.println(httpCode); // -1
 Serial.println(payload); // nothing

 http.end();

Look at your URL:

http://localhost:3003/record

What does that mean?

localhost is shorthand for a special IP address - 127.0.0.1 - which means "this host"

You're not running the server you're trying to connect to on the ESP8266, so you can't use localhost there (the ESP8266 probably wouldn't resolve the name localhost anyway).

You need to replace localhost with the name or IP address of the server that your Node Express code is running on.