ESP32 Posting Requests to Local Webserver

Code used in this demonstration:

Python Server Code:

# Tinker Foundry Example Python Code

# Python web server to work with ESP32 POST request

# This runs on your local computer, connected on the same WiFi network as your ESP32 controller

from http.server import BaseHTTPRequestHandler, HTTPServer

hostName = "192.168.xx.xxx" # use ipconfig in console (command prompt) to get the "IPv4 Address" of this machine

serverPort = 8080

# BaseHTTPRequestHandler class is used to handle the HTTP requests that arrive at the server

class MyServer(BaseHTTPRequestHandler):

    def do_POST(self): # handle POST request from ESP32 (or anything else, really)

        content_length = int(self.headers['Content-Length']) # Gets size of data

        post_data = self.rfile.read1(content_length) # Gets data

        print("Post Data: ")

        print(post_data.decode('utf-8')) # This is the message from the POST request

        self.send_response(200) # OK HTTP response

        self.send_header('Content-type','text/plain')

        self.end_headers()

        # Do some checks and send response message back to POST requester...

        if (post_data.decode('utf-8') == "Tinker Foundry"):

           message = "Welcome, great one!"

        else:

           message = "Access denied, creep!"

        self.wfile.write(bytes(message, "utf-8"))

 

if __name__ == "__main__":        

    webServer = HTTPServer((hostName, serverPort), MyServer) # HTTPServer

    print("Server started http://%s:%s" % (hostName, serverPort))

    try:

        webServer.serve_forever()

    except KeyboardInterrupt:

        pass

    webServer.server_close()

    print("Server stopped.")

ESP32 C-Code for HTTP POST Requests to Server:

// Tinker Foundry

// ESP32 Code for sending a POST request to a local WiFi connected server

// Sends a POST request to server that contains text from Serial input

#include <WiFi.h>

#include <HTTPClient.h>

const char* ssid     = "xxxxxxxx";   //input your wifi name

const char* password = "xxxxxxxx";   //input your wifi password

// set up server name with port - don't forgot the trailing forward slash!

const char* server_name = "http://192.168.xx.xxx:8080/";

void setup() {

  Serial.begin(115200);

  Serial.setDebugOutput(true);

  Serial.println();

  // Setup WiFi...

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {

    delay(500);

    Serial.print(".");

  }

  Serial.println("");

  Serial.println("WiFi connected");

  Serial.print("Msg: Ready! Use 'http://");

  Serial.print(WiFi.localIP());

  Serial.println("' to connect");

}

// Main Loop

void loop() {

  delay(500);

  Serial.println("Ready for Input.");

  // wait for serial input to send out as part of http request

  while (Serial.available() == 0){}

  String testStr = Serial.readString();

  testStr.trim();

  if (testStr != "Skip")

  {

    // check WiFi status

    if (WiFi.status() == WL_CONNECTED)

    {

      HTTPClient http;

      http.begin(server_name);

      http.addHeader("Content-Type", "text/plain");

      // Define data to send with HTTP POST request; in this case, whatever was input on the serial interface

      //String httpRequestData = "Input=" + testStr;

      String httpRequestData = testStr;

      // Send HTTP POST request

      int httpResponseCode = http.POST(httpRequestData);

      

      // Check the HTTP Response code

      if (httpResponseCode > 0){

        Serial.print("Good HTTP response code: ");

      } else {

        Serial.print("Bad HTTP response code: ");

      }

      Serial.println(httpResponseCode);

      String response = http.getString();

      Serial.print("Response: ");

      Serial.println(response);

      http.end(); // Free up resources

    } else {

      Serial.println("WiFi Connection Error.");

    }

  } else

  {

    Serial.println("Skip");

  }

}