working version

producer.py

@@ -5,30 +5,26 @@ import nats
 NATS_SERVER = "nats://localhost:4222"
 TOKEN = "dfji348934jdd0i24uhjd29834ijrr0345jo0r3j034n"
 
+count = 0
 
-async def message_handler(msg):
+async def main():
+    nc = await nats.connect(NATS_SERVER, token=TOKEN)
+
+    async def message_handler(msg):
         subject = msg.subject
         reply = msg.reply
         data = msg.data.decode()
+        global count
         print(f"Received a message on '{subject} {reply}': {data}")
-
+        await nc.publish(reply, f"response-{count}".encode("utf-8"))
-async def main():
+        count = count + 1
-    # It is very likely that the demo server will see traffic from clients other than yours.
-    # To avoid this, start your own locally and modify the example to use it.
-    nc = await nats.connect(NATS_SERVER, token=TOKEN)
-
-    # You can also use the following for TLS against the demo server.
-    #
-    # nc = await nats.connect("tls://demo.nats.io:4443")
-
-
 
     # Simple publisher and async subscriber via coroutine.
+    await nc.subscribe("foo", cb=message_handler)
+    await nc.subscribe("foo2", cb=message_handler)
+
     while True:
-        sub = await nc.subscribe("foo", cb=message_handler)
+        await asyncio.sleep(1)
-        await asyncio.sleep(0.1)
-
-
 
 if __name__ == '__main__':
     try:

publish.py

@@ -1,29 +1,31 @@
 import asyncio
+from http.client import responses
+
 import nats
 
 NATS_SERVER = "nats://localhost:4222"
 TOKEN = "dfji348934jdd0i24uhjd29834ijrr0345jo0r3j034n"
 
 
-async def message_handler(msg):
-    subject = msg.subject
-    reply = msg.reply
-    data = msg.data.decode()
-    print(f"Received a message on '{subject} {reply}': {data}")
-
 async def main():
     # It is very likely that the demo server will see traffic from clients other than yours.
     # To avoid this, start your own locally and modify the example to use it.
     nc = await nats.connect(NATS_SERVER, token=TOKEN)
     inbox = nc.new_inbox()
-    sub = await nc.subscribe("foo")
+    sub = await nc.subscribe("foo2")
+
+    async def message_handler(msg):
+        subject = msg.subject
+        reply = msg.reply
+        data = msg.data.decode()
+        print(f"Received a message on '{subject} {reply}': {data}")
 
     i = 0
     while True:
-        msg = await nc.publish("foo", b"message", reply=inbox)
+        response = await nc.request("foo", b"message")
+        print(f"{response=}")
         await asyncio.sleep(5)
 
-
 if __name__ == '__main__':
     asyncio.run(main())