solved timeout issue and allowed peer to peer using 2 esp32

[amr-kasem]

I've modified to accept connections so work as callee
I've created a stun heartbeat to preserve connection up
changes are minimal
I've tested this using datachannel
to establish the datachannel I used this py code

import paho.mqtt.client as mqtt import json import time # MQTT Broker Configuration MQTT_BROKER = "192.168.50.127" # Change this to your MQTT broker address MQTT_PORT = 1883 # Default MQTT port MQTT_KEEPALIVE = 60 # MQTT Topics CALLER_INVOKE_TOPIC = "/c76c2b3a-74ee-48f3-8fc2-7e51a1bd6a74/invoke" CALLER_RESULT_TOPIC = "/c76c2b3a-74ee-48f3-8fc2-7e51a1bd6a74/result" CALLEE_INVOKE_TOPIC = "/86e786f8-b6ec-446d-bf6a-2a715f61c0ad/invoke" CALLEE_RESULT_TOPIC = "/86e786f8-b6ec-446d-bf6a-2a715f61c0ad/result" # MQTT Client Setup client = mqtt.Client() # ID Mapping Storage id_map = {} # Maps request IDs from caller to callee and vice versa def on_message(client, userdata, msg): """Handles incoming MQTT messages.""" global id_map try: payload = json.loads(msg.payload.decode()) response_id = payload.get("id") response_result = payload.get("result") if msg.topic == CALLER_RESULT_TOPIC: print(f"[CALLER RESULT] Received (ID {response_id}): {payload}") # Map the caller request ID to a new ID for the callee new_id = response_id + 1000 # Example mapping logic (avoid conflicts) id_map[new_id] = response_id # Send offer to callee answer_request = { "jsonrpc": "2.0", "method": "answer", "params": response_result, "id": new_id } print(f"[CALLEE INVOKE] Forwarding offer to callee with new ID {new_id}") client.publish(CALLEE_INVOKE_TOPIC, json.dumps(answer_request)) elif msg.topic == CALLEE_RESULT_TOPIC: print(f"[CALLEE RESULT] Received (ID {response_id}): {payload}") # Get original caller ID from the mapping original_id = id_map.get(response_id, response_id) # Send answer back to caller final_answer = { "jsonrpc": "2.0", "method": "answer", "params": response_result, "id": original_id } print(f"[CALLER INVOKE] Forwarding answer to caller with original ID {original_id}") client.publish(CALLER_INVOKE_TOPIC, json.dumps(final_answer)) # Clean up ID mapping if response_id in id_map: del id_map[response_id] except Exception as e: print(f"Error processing message on {msg.topic}: {e}") def main(): global client # Connect MQTT Callbacks client.on_message = on_message # Connect to MQTT Broker client.connect(MQTT_BROKER, MQTT_PORT, MQTT_KEEPALIVE) # Subscribe to result topics client.subscribe(CALLER_RESULT_TOPIC) client.subscribe(CALLEE_RESULT_TOPIC) # Start MQTT loop in background thread client.loop_start() print("Press s and then enter to send offer request...") while True: try: key = input() if key == "s": # Generate a unique ID for the offer request request_id = int(time.time()) # Use current timestamp as a unique ID id_map[request_id] = request_id # Store original mapping # Send WebRTC Offer Request to Caller offer_request = { "jsonrpc": "2.0", "method": "offer", "params": "", "id": request_id } print(f"[CALLER INVOKE] Sending offer request with ID {request_id}") client.publish(CALLER_INVOKE_TOPIC, json.dumps(offer_request)) except KeyboardInterrupt: break client.loop_stop() if __name__ == "__main__": main()