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MQTT Subscriber Failed to Subscribe to the Same Topic With MQTT Publisher

I'm trying to make a simple "transit schedule changes" program using python MQTT where the publisher can input flight number (will be used as topic) and new flight time, while the transit location will be picked random from given list.
The subscriber will have to input flight number too which will be used as topic. But in my codes, it looks like the subscriber failed to get the message published to the same topic because it keeps on printing Connected Successfully (I'm using client.loop_forever()). Can someone please help me to figure out what's wrong with my code?
This is my first time asking question, so please ask me if something isn't clear from my explanation. Thank you so much :)
Publisher:
import paho.mqtt.client as mqtt
import time
from datetime import datetime, date
import random
def on_connect(client, userdata, flags, rc):
if (rc==0):
global connected
connected = True
#print("Successfully Connected.")
client.on_publish = on_publish
else:
print("Failed to connect.")
def on_publish(client, userdata, mid):
print("Published successfully. MID: "+str(mid))
listTransit = ["Singapura", "Qatar", "Korea Selatan", "Turki", "Republik Tiongkok",
"Amerika Serikat", "Jepang", "Uni Emirat Arab", "Oman", "Islandia"]
broker_address="broker.emqx.io"
client = mqtt.Client("Publisher")
client.on_connect = on_connect
client.connect(broker_address, port=1883)
client.loop_start()
topic = input("Masukkan nomor penerbangan: ")
negaraTujuan = input("negara tujuan: ")
print("Masukkan waktu penerbangan baru (Format: [jam::menit::detik])")
str_time = input()
Date = date.today()
Time = datetime.strptime(str_time, '%H::%M::%S').time()
Location = random.randrange(0,len(listTransit))
if (listTransit[Location] != negaraTujuan):
message = Date.strftime("%Y/%m/%d")+"\nTujuan: "+negaraTujuan+"\nLokasi Transit : "+listTransit[Location]+"\nJam terbang : "+Time.strftime("%H:%M:%S")
client.publish(topic, message)
print("Topic: ",topic)
print(message)
else:
while listTransit[Location] == negaraTujuan:
Location = random.randrange(0,len(listTransit))
message = Date.strftime("%Y/%m/%d")+"\nTujuan: "+negaraTujuan+"\nLokasi Transit : "+listTransit[Location]+"\nJam terbang : "+Time.strftime("%H:%M:%S")
client.publish(topic, message)
print(message)
client.loop_stop()
Subscriber:
import paho.mqtt.client as mqtt
import time
from datetime import datetime, datetime
import re
def on_connect(client, userdata, flags, rc):
if (rc == 0):
print("Connected successfully.")
#global topic
#topic = input("Masukkan nomor penerbangan anda: ")
#client.subscribe(topic)
else:
print("Connection failed.")
def on_message(client, userdata, msg):
print("on_message callback function activated.")
sched = str(msg.payload.decode("utf-8"))
print(sched)
def on_subscribe(client, userdata, mid, granted_qos):
print("Subscribed to "+topic+" successfully")
broker_address="broker.emqx.io"
topic = input("Masukkan nomor penerbangan anda: ")
negaraTujuan = input("negara tujuan: ")
client = mqtt.Client("Subscriber")
client.subscribe(topic)
client.on_connect = on_connect
client.on_message = on_message
client.on_subscribe = on_subscribe
client.connect(broker_address, port=1883)
client.loop_forever()
what I got from running both codes are
Masukkan nomor penerbangan: YT05TA
negara tujuan: Australia
Masukkan waktu penerbangan baru (Format: [jam::menit::detik])
12::50::00
Topic: YT05TA
2023/01/03
Tujuan: Australia
Lokasi Transit : Amerika Serikat
Jam terbang : 12:50:00
Published successfully. MID: 1
from Publisher
and
Masukkan nomor penerbangan anda: YT05TA
negara tujuan: Australia
Connected successfully.
Connected successfully.
Connected successfully.
Connected successfully.
from subscriber. It doesn't even print the print("on_message callback function activated.")

You are using a public broker, so that means it is likely to have LOTS of over clients.
Every client MUST have a UNIQUE Client ID, so using Publisher and Subscriber is very likely to clash with other clients.
The MQTT specification says the broker must disconnect the currently connected client when a new client connects with the same Client ID. As most client libraries will try and reconnect when they are disconnects this leads to a battle between the two clients to stay connected.
Change them both to random values

multiple protocols in a single Jina Flow?

I would like to serve both gRPC and HTTP in my flow, but the flow description only allows a single value in the protocol parameter. Is it possible to add both? If not, do i have to deploy two flows or is there a better workaround?
The documentation doesn't mention if i can have two gateways from what i can see?
f = Flow(protocol='grpc', port=12345).add(uses=FooExecutor)
with f:
client = Client(port=12345)
docs = client.post(on='/')
print(docs.texts)

Unfortunately by default, no.
But you can develop your own custom gateway that enables both protocols at the same time.
A sample custom gateway looks like the following (borrowed from here)
import grpc
from grpc_health.v1 import health, health_pb2, health_pb2_grpc
from grpc_reflection.v1alpha import reflection
from pydantic import BaseModel
from uvicorn import Config, Server
from jina import Gateway, __default_host__
from jina.proto import jina_pb2, jina_pb2_grpc
class DummyResponseModel(BaseModel):
protocol: str
class MultiProtocolGateway(Gateway):
def __init__(self, **kwargs):
super().__init__(**kwargs)
self.http_port = self.ports[0]
self.grpc_port = self.ports[1]
self.health_servicer = health.HealthServicer(experimental_non_blocking=True)
async def _setup_http_server(self):
from fastapi import FastAPI
app = FastAPI(
title='HTTP Server',
)
#app.get(path='/', response_model=DummyResponseModel)
def _get_response():
return {'protocol': 'http'}
self.http_server = Server(
Config(app, host=__default_host__, port=self.http_port)
)
async def _setup_grpc_server(self):
self.grpc_server = grpc.aio.server()
jina_pb2_grpc.add_JinaRPCServicer_to_server(
self.streamer._streamer, self.grpc_server
)
service_names = (
jina_pb2.DESCRIPTOR.services_by_name['JinaRPC'].full_name,
reflection.SERVICE_NAME,
)
# Mark all services as healthy.
health_pb2_grpc.add_HealthServicer_to_server(
self.health_servicer, self.grpc_server
)
for service in service_names:
self.health_servicer.set(service, health_pb2.HealthCheckResponse.SERVING)
reflection.enable_server_reflection(service_names, self.grpc_server)
self.grpc_server.add_insecure_port(f'{__default_host__}:{self.grpc_port}')
await self.grpc_server.start()
async def setup_server(self):
await self._setup_http_server()
await self._setup_grpc_server()
async def run_server(self):
await self.http_server.serve()
await self.grpc_server.wait_for_termination()
async def shutdown(self):
self.http_server.should_exit = True
await self.grpc_server.stop(0)
await self.http_server.shutdown()
self.health_servicer.enter_graceful_shutdown()
#property
def _should_exit(self) -> bool:
return self.http_server.should_exit
And you can access it in the following way:
from xxx import MultiProtocolGateway
from xxx import MyExecutor
from jina import Flow, Client, DocumentArray
http_port = 51000
grpc_port = 52000
flow = Flow().config_gateway(
uses=MultiProtocolGateway,
port=[http_port, grpc_port],
protocol=['http', 'grpc'],
).add(MyExecutor)
with flow:
c1 = Client(host='http://0.0.0.0:51000)
c1.post(on='/', inputs=DocumentArray().empty(5))
c2 = Client(host='grpc://0.0.0.0:52000)
c2.post(on='/', inputs=DocumentArray().empty(5))

Why does the paho python client publish short messages but not long ones

This works :
while True:
print('')
command_input = input()
if command_input == 'q':
break
mcp = Mqtt_command_publisher
mcp.publish_command(device_ids, command_input)
But this does not:
class Mqtt_command_bl:
def update_minutes_to_run_at(json):
if not json['device_ids']:
return 'Request must contain device ids'
device_ids = json['device_ids']
minutes_to_run_at = json['minutes_to_run_at']
minutes_to_run_at_command_section = ''
for i in minutes_to_run_at:
m = '"{}",'.format(i)
if i == minutes_to_run_at[len(minutes_to_run_at) - 1]:
m = '"{}"'.format(i)
minutes_to_run_at_command_section += m
#command_input = 'jq \'.+{{minutes_to_run_at:[{}]}}\' /home/pi/hallmonitor_lite/config.json > /home/pi/hallmonitor_lite/tmp.json && mv /home/pi/hallmonitor_lite/tmp.json /home/pi/hallmonitor_lite/new_config.json'.format(minutes_to_run_at_command_section)
command_input = 'mkdir /home/pi/hallmonitor_lite/hello_world'
mcp = Mqtt_command_publisher
mcp.publish_command(device_ids, command_input)
return 'Success'
The class they both call:
class Mqtt_command_publisher:
def publish_command(device_ids, command_input):
mqtt_msg = json.dumps({'device_ids':device_ids,'command':command_input})
print('\n{}'.format(mqtt_msg))
client = mqtt.Client()
client.connect('********', ****, 30)
client.publish('topic/commands', mqtt_msg)
client.disconnect()
Looking at the print statements output from the Mqtt_command_publisher, the output can be the exact same, however, only one of them will execute, and I don't see why one works and the other does not.
I tried this command for testing: mkdir /home/pi/hallmonitor_lite/hello_world
This is the receiving part:
device_id = 0
with open('/home/pi/hallmonitor_lite/config.json') as json_data_file:
data = json.load(json_data_file)
device_id = data['device_id']
def on_connect(client, userdata, flags, rc):
print("Connected with result code: " + str(rc))
client.subscribe("topic/commands")
def on_message(client, userdata, msg):
mqtt_message = msg.payload.decode()
print(mqtt_message)
ids_and_command = json.loads(mqtt_message)
if str(device_id) in ids_and_command['device_ids'] or not ids_and_command['device_ids']:
print(('Executing: {}').format(ids_and_command['command']))
os.system(ids_and_command['command'])
client = mqtt.Client()
client.connect("********", ****, 30)
client.on_connect = on_connect
client.on_message = on_message
client.loop_forever()
Any ideas?

The problem is most likely because the second set of code is creating a message bigger than will fit in a single TCP packet.
This is a problem because you are not running the client network loop so the client.publish command can only send a single packet, the rest of the message would have been sent by the network loop, but even if it was running you are calling disconnect immediately after the publish call.
The client is not meant to be spun up for a single message like that, it is meant to be started and then left running with you just calling the publish method when you want to send a message. If you don't want to do that or can't for some reason there is a specific helper class in the paho python package that will do all the heavy lifting of starting the client, sending the message and then tearing everything down nicely. The docs for the single publish are here.
import paho.mqtt.publish as publish
publish.single("paho/test/single", "payload", hostname="mqtt.eclipse.org")

Python, websocket auto-close on some machines

I've written some api to communicate with a website using websocketapp. It works fine only on 2 pc. If i put my code on every other pc the websocket doesnt receive any message and closes. I've tried a lot of different machines and operating systems, many version of python (included the same that works), wireless and wired connection but nothing changed. There's no error or exception. What can it be?
EDIT: i don't own the website or the server. All other methods send messages and parse the response in on_socket_message
import requests
import websocket
import time
from threading import Thread
from datetime import datetime
import json
from position import Position
from constants import ACTIVES
class IQOption():
practice_balance = 0
real_balance = 0
server_time = 0
positions = {}
instruments_categories = ["cfd","forex","crypto"]
top_assets_categories = ["forex","crypto","fx-option"]
instruments_to_id = ACTIVES
id_to_instruments = {y:x for x,y in ACTIVES.items()}
market_data = {}
binary_expiration_list = {}
open_markets = {}
digital_strike_list = {}
candle_data = []
latest_candle = 0
position_id = 0
quotes =[]
position_id_list=[]
def __init__(self,username,password,host="iqoption.com"):
self.username = username
self.password = password
self.host = host
self.session = requests.Session()
self.generate_urls()
self.socket = websocket.WebSocketApp(self.socket_url,on_open=self.on_socket_connect,on_message=self.on_socket_message,on_close=self.on_socket_close,on_error=self.on_socket_error)
def generate_urls(self):
"""Generates Required Urls to operate the API"""
#https://auth.iqoption.com/api/v1.0/login
self.api_url = "https://{}/api/".format(self.host)
self.socket_url = "wss://{}/echo/websocket".format(self.host)
self.login_url = self.api_url+"v1.0/login"
self.profile_url = self.api_url+"profile"
self.change_account_url = self.profile_url+"/"+"changebalance"
self.getprofile_url = self.api_url+"getprofile"
def login(self):
"""Login and set Session Cookies"""
print("LOGIN")
data = {"email":self.username,"password":self.password}
self.log_resp = self.session.request(url="https://auth.iqoption.com/api/v1.0/login",data=data,method="POST")
requests.utils.add_dict_to_cookiejar(self.session.cookies, dict(platform="9"))
self.__ssid = self.log_resp.cookies.get("ssid")
print(self.__ssid)
self.start_socket_connection()
time.sleep(1) ## artificial delay to complete socket connection
self.log_resp2 = self.session.request(url="https://eu.iqoption.com/api/getprofile",method="GET")
ss = self.log_resp2._content.decode('utf-8')
js_ss=json.loads(ss)
self.parse_account_info(js_ss)
self.balance_id = js_ss["result"]["balance_id"]
self.get_instruments()
self.get_top_assets()
self.setOptions()
#self.getFeatures()
time.sleep(1)
print(js_ss["isSuccessful"])
return js_ss["isSuccessful"]
def on_socket_message(self,socket,message):
#do things
def on_socket_connect(self,socket):
"""Called on Socket Connection"""
self.initial_subscriptions()
print("On connect")
def initial_subscriptions(self):
self.send_socket_message("ssid",self.__ssid)
self.send_socket_message("subscribe","tradersPulse")
def on_socket_error(self,socket,error):
"""Called on Socket Error"""
print(message)
def on_socket_close(self,socket):
"""Called on Socket Close, does nothing"""
def start_socket_connection(self):
"""Start Socket Connection"""
self.socket_thread = Thread(target=self.socket.run_forever)
self.socket_thread.start()
def send_socket_message(self,name,msg):
#print(msg)
data = {"name":name,"msg":msg}
self.socket.send(json.dumps(data))

Here is an example running under Gevent Websockets. This makes it ASYNC (which I suspect is part of your problem) and allows for bidirectional communication.
import gevent
from gevent import monkey, signal, Timeout, sleep, spawn as gspawn
monkey.patch_all()
from gevent.pywsgi import WSGIServer
from geventwebsocket.handler import WebSocketHandler
from geventwebsocket import WebSocketError
import bottle
from bottle import get, route, template, request, response, abort, static_file
import ujson as json
#route('/static/<filepath:path>')
def server_static(filepath):
return static_file(filepath, root='static')
#route('/ws/remote')
def handle_websocket():
wsock = request.environ.get('wsgi.websocket')
if not wsock:
abort(400, 'Expected WebSocket request.')
while 1:
try:
message = ''
with Timeout(2, False) as timeout:
message = wsock.receive()
if message:
message = json.loads(message)
if 'command' in message:
r.command(message['command'])
except WebSocketError:
break
except Exception as exc:
print(str(exc))
#get('/')
def remote():
return template('templates/remote.tpl', title='WebsocketTest', websocket=WEBSOCKET, command='command', status=status)
if __name__ == '__main__':
r=None
status="Connecting..."
gspawn(initialize)
print 'Started...'
HOST = socket.gethostbyname(socket.gethostname())
HOST = 'localhost'
WEBSOCKET = 'ws://{}/ws/remote'.format(HOST)
botapp = bottle.app()
server = WSGIServer(("0.0.0.0", 80), botapp, handler_class=WebSocketHandler)
def shutdown():
print('Shutting down ...')
server.stop(timeout=60)
exit(signal.SIGTERM)
gevent.signal(signal.SIGTERM, shutdown)
gevent.signal(signal.SIGINT, shutdown) #CTRL C
server.serve_forever()
Then in your HTML you really should use reconnecting websocket library
https://github.com/joewalnes/reconnecting-websocket
<button id="TRIGGERED" type="button" class="btn btn-outline-primary">TRIGGER</button>
<script type="text/javascript" src="/static/reconnecting-websocket.min.js"></script>
<script>
var ws = new ReconnectingWebSocket('{{websocket}}');
ws.reconnectInterval = 3000;
ws.maxReconnectAttempts = 10;
ws.onmessage = function (evt) {
var wsmsg = JSON.parse(evt.data);
console.log(evt.data)
};
$("button").click(function() {
<!--console.log(this.id);-->
ws.send(JSON.stringify({'{{command}}': this.id}));
});
</script>

Processing event hub data using python

I am using azure event hub python SDK to send to and receive messages from event hub following this link.https://github.com/Azure/azure-event-hubs-python/tree/develop. I can successfully send and receive messages. But how do i parse the messages and retrieve the data from the event data object. Please find the code below.
import os
import sys
#import logging
from azure.eventhub import EventHubClient, Receiver, Offset
ADDRESS = 'sb://####.servicebus.windows.net/#####'
USER = '##########'
KEY = '##################################'
CONSUMER_GROUP = "$default"
OFFSET = Offset("-1")
PARTITION = "1"
total = 0
last_sn = -1
last_offset = "-1"
try:
if not ADDRESS:
raise ValueError("No EventHubs URL supplied.")
client = EventHubClient(ADDRESS, debug=False, username=USER, password=KEY)
receiver = client.add_receiver(CONSUMER_GROUP, PARTITION, prefetch=5000,
offset=OFFSET)
client.run()
try:
batched_events = receiver.receive(timeout=20)
except:
raise
finally:
client.stop()
for event_data in batched_events:
last_offset = event_data.offset.value
last_sn = event_data.sequence_number
total += 1
print("Partition {}, Received {}, sn={} offset={}".format(
PARTITION,
total,
last_sn,
last_offset))
except KeyboardInterrupt:
pass
if i try to view the event_data received i can see the below message.
event_data
<azure.eventhub.common.EventData at 0xd4f1358>
event_data.message
<uamqp.message.Message at 0xd4f1240>
Any help on the above on how to parse this message to extract the data

As of 1.1.0, there are new utility methods to extract the actual data of the message:
body_as_str
body_as_json
So, what used to be
import json
event_obj = json.loads(next(event_data.body).decode('UTF-8'))
Is now:
event_obj = event_data.body_as_json()

For people using the Event Hub version 5.2.0 -- latest as of today (GitHub, Reference Docs), it's the same as the 1.1.0 version, i.e. use body_as_str() or body_as_json(). But the client has changed -- there's an EventHubProducerClient and an EventHubConsumerClient in the new version. To print the body of an event received:
from azure.eventhub import EventHubConsumerClient
connection_str = '<< CONNECTION STRING FOR THE EVENT HUBS NAMESPACE >>'
consumer_group = '<< CONSUMER GROUP >>'
eventhub_name = '<< NAME OF THE EVENT HUB >>'
client = EventHubConsumerClient.from_connection_string(
connection_str, consumer_group, eventhub_name=eventhub_name
)
def on_event_batch(partition_context, events):
partition_context.update_checkpoint()
for e in events:
print(e.body_as_str())
with client:
client.receive_batch(
on_event_batch=on_event_batch,
starting_position="-1", # "-1" is from the beginning of the partition.
)