Lifecycle Connection Failure Connection failed with exception:AWS_ERROR_MQTT5_CONNACK_CONNECTION_REFUSED: Remote endpoint rejected the CONNECT attempt by returning an unsuccessful CONNACK

[YJY1220]

Getting error as below:

Lifecycle Connection Failure
Connection failed with exception:AWS_ERROR_MQTT5_CONNACK_CONNECTION_REFUSED: Remote endpoint rejected the CONNECT attempt by returning an unsuccessful CONNACK

it appears when i start in terminal

chmod +x start.sh
./start.sh

At first, I thought it was a path problem, certificate problem, or code problem, but even though I changed the location of the existing sample code and set it to an absolute path, the error continues to occur. Why is that?

[My PATH]
root-CA.crt : /home/pi/git/ControlTower/src/ct_package/ct_package/root-CA.crt
Control-Tower.private.key : /home/pi/git/ControlTower/src/ct_package/ct_package/Control-Tower.private.key
Control-Tower.cert.pem : /home/pi/git/ControlTower/src/ct_package/ct_package/Control-Tower.cert.pem
start.sh : /home/pi/git/ControlTower/src/ct_package/ct_package/start.sh
mqtt_communication.py : /home/pi/git/ControlTower/src/ct_package/ct_package/mqtt_communication.py
command_line_utils.py : /home/pi/git/ControlTower/src/ct_package/ct_package/command_line_utils.py

[code]

### mqtt_communication.py

from awsiot import mqtt5_client_builder
from awscrt import mqtt5, http
import threading
from concurrent.futures import Future
import time
import json
from utils.command_line_utils import CommandLineUtils

TIMEOUT = 100
topic_filter = "test/topic"

# cmdData is the arguments/input from the command line placed into a single struct for
# use in this sample. This handles all of the command line parsing, validating, etc.
# See the Utils/CommandLineUtils for more information.
cmdData = CommandLineUtils.parse_sample_input_mqtt5_pubsub()

received_count = 0
received_all_event = threading.Event()
future_stopped = Future()
future_connection_success = Future()

# Callback when any publish is received
def on_publish_received(publish_packet_data):
    publish_packet = publish_packet_data.publish_packet
    assert isinstance(publish_packet, mqtt5.PublishPacket)
    print("Received message from topic'{}':{}".format(publish_packet.topic, publish_packet.payload))
    global received_count
    received_count += 1
    if received_count == cmdData.input_count:
        received_all_event.set()


# Callback for the lifecycle event Stopped
def on_lifecycle_stopped(lifecycle_stopped_data: mqtt5.LifecycleStoppedData):
    print("Lifecycle Stopped")
    global future_stopped
    future_stopped.set_result(lifecycle_stopped_data)


# Callback for the lifecycle event Connection Success
def on_lifecycle_connection_success(lifecycle_connect_success_data: mqtt5.LifecycleConnectSuccessData):
    print("Lifecycle Connection Success")
    global future_connection_success
    future_connection_success.set_result(lifecycle_connect_success_data)


# Callback for the lifecycle event Connection Failure
def on_lifecycle_connection_failure(lifecycle_connection_failure: mqtt5.LifecycleConnectFailureData):
    print("Lifecycle Connection Failure")
    print("Connection failed with exception:{}".format(lifecycle_connection_failure.exception))


if __name__ == '__main__':
    print("\nStarting MQTT5 before editing\n")
    message_count = cmdData.input_count
    message_topic = cmdData.input_topic

    # 커스텀 메시지가 제공되지 않은 경우 기본 메시지를 설정합니다.
    if not cmdData.input_message or cmdData.input_message == "Hello World! ":
        cmdData.input_message = {
            "timestamp": '2024-08-16',
            "robot_id": 1,
            "trash_type": "plastic",
            "trash_location": "Seoul",
        }

    message_string = cmdData.input_message  # JSON 객체

    # JSON 객체를 문자열로 변환하여 사용하도록 합니다.
    if isinstance(message_string, dict):
        message_string = json.dumps(message_string)


    # Create the proxy options if the data is present in cmdData
    proxy_options = None
    if cmdData.input_proxy_host is not None and cmdData.input_proxy_port != 0:
        proxy_options = http.HttpProxyOptions(
            host_name=cmdData.input_proxy_host,
            port=cmdData.input_proxy_port)

    # Create MQTT5 client
    client = mqtt5_client_builder.mtls_from_path(
        endpoint=cmdData.input_endpoint,
        port=cmdData.input_port,
        cert_filepath=cmdData.input_cert,
        pri_key_filepath=cmdData.input_key,
        ca_filepath=cmdData.input_ca,
        http_proxy_options=proxy_options,
        on_publish_received=on_publish_received,
        on_lifecycle_stopped=on_lifecycle_stopped,
        on_lifecycle_connection_success=on_lifecycle_connection_success,
        on_lifecycle_connection_failure=on_lifecycle_connection_failure,
        client_id=cmdData.input_clientId)
    print("MQTT5 Client Created")

    if not cmdData.input_is_ci:
        print(f"Connecting to {cmdData.input_endpoint} with client ID '{cmdData.input_clientId}'...")
    else:
        print("Connecting to endpoint with client ID")

    client.start()
    lifecycle_connect_success_data = future_connection_success.result(TIMEOUT)
    connack_packet = lifecycle_connect_success_data.connack_packet
    negotiated_settings = lifecycle_connect_success_data.negotiated_settings
    if not cmdData.input_is_ci:
        print(
            f"Connected to endpoint:'{cmdData.input_endpoint}' with Client ID:'{cmdData.input_clientId}' with reason_code:{repr(connack_packet.reason_code)}")

    # Subscribe

    print("Subscribing to topic '{}'...".format(message_topic))
    subscribe_future = client.subscribe(subscribe_packet=mqtt5.SubscribePacket(
        subscriptions=[mqtt5.Subscription(
            topic_filter=message_topic,
            qos=mqtt5.QoS.AT_LEAST_ONCE)]
    ))
    suback = subscribe_future.result(TIMEOUT)
    print("Subscribed with {}".format(suback.reason_codes))

    # Publish message to server desired number of times.
    # This step is skipped if message is blank.
    # This step loops forever if count was set to 0.
    if message_string:
        if message_count == 0:
            print("Sending messages until program killed")
        else:
            print("Sending {} message(s)".format(message_count))

        publish_count = 1
        while (publish_count <= message_count) or (message_count == 0):
            # JSON 객체를 문자열로 변환
            message_payload = json.dumps(message_string)
            message = "{} [{}]".format(message_payload, publish_count)
            print("Publishing message to topic '{}': {}".format(message_topic, message))
            publish_future = client.publish(mqtt5.PublishPacket(
                topic=message_topic,
                payload=message_payload.encode('utf-8'),  # 문자열로 변환하여 payload로 사용
                qos=mqtt5.QoS.AT_LEAST_ONCE
            ))

            publish_completion_data = publish_future.result(TIMEOUT)
            print("PubAck received with {}".format(repr(publish_completion_data.puback.reason_code)))
            time.sleep(1)
            publish_count += 1

    received_all_event.wait(TIMEOUT)
    print("{} message(s) received.".format(received_count))

    # Unsubscribe

    print("Unsubscribing from topic '{}'".format(message_topic))
    unsubscribe_future = client.unsubscribe(unsubscribe_packet=mqtt5.UnsubscribePacket(
        topic_filters=[message_topic]))
    unsuback = unsubscribe_future.result(TIMEOUT)
    print("Unsubscribed with {}".format(unsuback.reason_codes))

    print("Stopping Client")
    client.stop()

    future_stopped.result(TIMEOUT)
    print("Client Stopped!")


### start.sh
#!/usr/bin/env bash
# stop script on error
set -e

# Check for python 3
if ! python3 --version &> /dev/null; then
  printf "\nERROR: python3 must be installed.\n"
  exit 1
fi

# Check to see if root CA file exists, download if not
if [ ! -f ./root-CA.crt ]; then
  printf "\nDownloading AWS IoT Root CA certificate from AWS...\n"
  curl https://www.amazontrust.com/repository/AmazonRootCA1.pem > root-CA.crt
fi

# Check to see if AWS Device SDK for Python exists, download if not
if [ ! -d ./aws-iot-device-sdk-python-v2 ]; then
  printf "\nCloning the AWS SDK...\n"
  git clone https://github.com/aws/aws-iot-device-sdk-python-v2.git --recursive
fi

# Check to see if AWS Device SDK for Python is already installed, install if not
if ! python3 -c "import awsiot" &> /dev/null; then
  printf "\nInstalling AWS SDK...\n"
  python3 -m pip install ./aws-iot-device-sdk-python-v2
  result=$?
  if [ $result -ne 0 ]; then
    printf "\nERROR: Failed to install SDK.\n"
    exit $result
  fi
fi

# run pub/sub sample app using certificates downloaded in package
printf "\nRunning mqtt_communication...\n"
#python3 /home/pi/git/ControlTower/src/ct_package/ct_package/mqtt_communication.py --endpoint an2dks8wwmmxc-ats.iot.us-east-1.amazonaws.com --port 8883 --cert /home/pi/git/ControlTower/src/ct_package/connect_device_package/Control-Tower.cert.pem --key /home/pi/git/ControlTower/src/ct_package/connect_device_package/Control-Tower.private.key --ca_file /home/pi/git/ControlTower/src/ct_package/connect_device_package/root-CA.crt --client_id iotconsole-e1dcd6bd-2ff9-4981-a261-9c5d45dff88b --topic sdk/test/python --count 5
python3 /home/pi/git/ControlTower/src/ct_package/ct_package/mqtt_communication.py --endpoint an2dks8wwmmxc-ats.iot.us-east-1.amazonaws.com --ca_file root-CA.crt --cert Control-Tower.cert.pem --key Control-Tower.private.key --client_id mqttTestStart --topic sdk/test/python --count 0
#python3 aws-iot-device-sdk-python-v2/samples/mqtt5_pubsub.py --endpoint an2dks8wwmmxc-ats.iot.us-east-1.amazonaws.com --ca_file root-CA.crt --cert Control-Tower.cert.pem --key Control-Tower.private.key --client_id basicPubSub --topic sdk/test/python --count 0

I simply moved the path from the given sample code to the path I wanted and changed the path code to an absolute path. But I keep getting the error. I am attaching a photo of my file structure.

[jmklix]

You seem to have opened this discussion on the wrong repo. This repo(aws-iot-device-sdk-cpp-v2) is for cpp while it looks like you are trying to do this with python (aws-iot-device-sdk-python-v2)

Regardless, I would check to make sure you have the correct policy to connect.

[YJY1220]

So should I wait or should I post a new discusion in your python repository?

[jmklix]

The choice is up to you, but I would recommend opening a new discussion to avoid any confusion and to help others in the future who are using python and run into a similar issue.

You can find a sample policy in this readme as well as other details for running the mqtt5 pubsub sample