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2022年12月28日星期三

Paho MQTT Python Client 使用手册

介紹

paho.mqtt.python 是一個MQTT用戶端python庫，能夠讓應用程式簡單方便的連接到MQTT代理進行消息發佈、訂閱主題和消息接收。

目前 paho.mqtt.python-1.5.1 版本支持5.0、3.1.1和3.1 MQTT協定，同時支援Python 2.7.9+或3.5+。

環境

MQTT代理：EMQ X Broker 4.2.6
Python 3.9.0
paho-mqtt 1.5.1

準備

參照 EMQ X Broker安裝啟動教程
成功啟動EMQ後，可通過流覽器訪問 http://localhost:18083 admin/public 進入EMQ控制台，在【工具 > Websocket】模組可方便進行用戶端連接、訂閱、消息接收、發佈等測試和調試工作
emqx_broker

Python 安裝省略
paho-mqtt 安裝

1. pip install paho-mqtt

快速開始

Python快速實現MQTT主題訂閱和消息接收

1. import paho.mqtt.client as mq_tt

4. def on_connect(client, userdata, flags, rc):

5. """

6. 回呼函數：當MQTT代理回應用戶端連接請求時觸發

7. :param client: 回檔返回的用戶端實例

8. :param userdata: Client()或user_data_set()中設置的私有使用者資料

9. :param flags: MQTT代理發送的回應標識

10. :param rc: 連接結果

11. 0：連接成功

12. 1：連接被拒絕 - 協議版本

13. 2: 連接被拒絕 - 用戶端識別字無效

14. 3：連接被拒絕 - 伺服器不可用

15. 4：連接被拒絕 - 用戶名或密碼錯誤

16. 5：連接被拒絕 - 未授權6-255：當前未使用

17. :return:

18. """

19. print("Connected with result code "+str(rc))

20. # 在on_connect()中進行消息訂閱，是因為如果丟失連接進行重連，主題也會重新被訂閱

21. client.subscribe("testTopic/#")

22.

23.

24. def on_message(client, userdata, message):

25. """

26. 回呼函數：當接收到MQTT代理發佈的消息時觸發

27. :param client: 回檔返回的用戶端實例

28. :param userdata: Client()或user_data_set()中設置的私有使用者資料

29. :param message: MQTTMessage的一個實例，這是一個包含主題，有效負載，qos，retain的類

30. :return:

31. """

32. print(message.topic+" "+str(message.payload))

33.

34.

35. mq_client = mq_tt.Client(client_id='www.cooooder.com')

36. mq_client.on_connect = on_connect

37. mq_client.on_message = on_message

38. # 連接到EMQX Broker MQTT代理

39. mq_client.connect("127.0.0.1", 1883, 60)

40.

41. # 阻塞式自動處理收發資料、自動處理重新連接，所有的資料處理邏輯都在預先設定好的回呼函數中進行的

42. mq_client.loop_forever()

在 EMQ X Broker - 【用戶端】可以看到用戶端已連接

emqx_client

在 EMQ X Broker - 【Websocket】發佈testTopic主題消息

emqx_publish

Python程式列印出接收到的消息

1. Connected with result code 0

2. testTopic b'{ "msg": "Hello, World!" }'

3. testTopic b'{ "msg": "Hello, World2!" }'

常用API

Client

Client類實例常規用法流程如下：

創建一個用戶端實例
使用任一 connect*() 方法連接到MQTT代理
調用任一 loop*() 方法保持與MQTT代理通訊
使用 subscribe() 方法訂閱一個主題並接收消息
使用 publish() 方法向MQTT代理發佈消息
使用 disconnect() 中斷與MQTT代理的連接

client()

1. # 構造方法

2. Client(client_id="", clean_session=True, userdata=None, protocol=MQTTv311, transport="tcp")

client_id

連接到MQTT代理時使用的唯一用戶端ID字串。如果為0或者為None，將隨機生成分配一個，這種情況下clean_session參數必須為True

clean_session

布林數值型別，用來確定用戶端類型。如果為True，當斷開連接時，MQTT代理將移除該用戶端的所有資訊；如果為False，用戶端則為持久用戶端，當斷開連接時，訂閱資訊和訊息佇列將被MQTT保存
當斷開連接時，用戶端不會丟棄自己發送的消息。調用 connect() 或者 reconnect() 將導致重新發送消息，只有使用 reinitialise() 可以將用戶端重置為初始狀態

userdata

使用者定義的任意類型資料作為 userdata 參數傳遞給回呼函數，可以通過調用user_data_set() 方法進行更新，不過會有點延遲

protocol

用戶端使用的MQTT協定版本，可以是 MQTTv31 或 MQTTv311

transport

傳輸形式，設置為websockets，則會通過websockets發送給MQTT，默認tcp

示例

1. import paho.mqtt.client as mqtt

3. mqttc = mqtt.Client()

connect()

1. connect(host, port=1883, keepalive=60, bind_address="")

用戶端連接MQTT代理，這是一個阻塞函數

host

代理的主機名稱或者IP位址

port

連接服務的埠，預設1883

keepalive

心跳檢測時長

bind_address

綁定此用戶端本地網路的IP位址

回呼函數

on_connect()

connect_async()

1. connect_async(host, port=1883, keepalive=60, bind_address="")

與 loop_start() 結合使用以非阻塞的形式進行連接，在調用 loop_start() 之前，連接不會完成

disconnect()

1. disconnect()

徹底與MQTT代理斷開，使用該方法斷開連接不會讓代理發送遺囑消息

回呼函數

on_disconnect()

enable_logger()

1. enable_logger(logger=None)

使用標準的Python日誌包啟用日誌記錄，可以與on_log回檔方法同時使用

reconnect()

1. reconnect()

使用之前的資訊配置重新連接代理，在調用之前必須先調用 connect*() 方法

reinitialise()

重置用戶端為初始化狀態，參數與 client() 一致

示例

1. mqttc.reinitialise()

loop()

1. loop(timeout=1.0, max_packets=1)

定期調用處理事件

timeout

最大阻塞的秒數

max_packets

已過期，不設置

示例

1. while True:

2. mqttc.loop()

loop_start() / loop_stop()

1. loop_start()

2. loop_stop(force=False)

這些函數實現了網路迴圈的執行緒介面，在執行connect*()之前或者之後調用一次 loop_start() ,後臺會自動運行一個執行緒調用 loop() ，這樣就釋放了主執行緒去執行其它工作，避免發生阻塞，這個調用也處理重新連接到代理。調用 loop_stop() 停止後臺執行緒

1. mqttc.connect("127.0.0.1")

2. mqttc.loop_start()

4. while True:

5. mqttc.publish("topicTest", 'test')

loop_forever()

阻塞式網路迴圈處理事件，直到用戶端調用 disconnect() 才會返回，它會自動重連

publish()

1. publish(topic, payload=None, qos=0, retain=False)

用戶端向MQTT代理發送一條消息

topic

消息發佈的主題，不能為None或者空字元

payload

發送的消息內容，如果沒有賦值或者賦值為None，則將使用零長度的消息。傳遞int或者float將會被轉換為該數位的字串，如果想發送真正的int或者float資料，使用 struct.pack() 去創建

消息的服務品質等級，必須為0 or 1 or 2

retain

設置為True，MQTT代理保留最後一條消息，以便分發給消息發佈後的訂閱者

回呼函數

on_publish()

Return MQTTMessageInfo對象

reconnect_delay_set()

1. reconnect_delay_set(min_delay=1, max_delay=120)

斷開連接後，用戶端將自動嘗試連接，每次嘗試間隔 [min_delay, max_delay] 秒，從min_delay開始逐漸加倍至max_delay，連接成功後，延遲重置為min_delay

subscribe()

1. subscribe(topic, qos=0)

訂閱一個或多個主題，該方法有三種不同的調用方式：

1. # 1. 字串和整數

2. subscribe("my/topic", 2)

3. # 2. 字串和整數元組

4. subscribe(("my/topic", 1))

5. # 3. 字串和整數元組的清單

6. # 單次調用多個主題，比多次調用subscribe更有效

7. subscribe([("my/topic", 0), ("another/topic", 2)])

Return 一個元組 (result, mid)

result

成功：MQTT_ERR_SUCCESS
失敗：(MQTT_ERR_NO_CONN, None)

消息ID

回呼函數

on_subscribe()

unsubscribe()

1. unsubscribe(topic)

取消一個或多個主題

topic

主題字串或者字串清單
Return 一個元組 (result, mid)

result

成功：MQTT_ERR_SUCCESS
失敗：(MQTT_ERR_NO_CONN, None)

消息ID

回呼函數

on_unsubscribe()

user_data_set()

1. user_data_set(userdata)

設置傳遞給回呼函數的使用者私有資料

username_pw_set()

1. username_pw_set(username，password = None)

設置用戶名和密碼（可選）供MQTT代理驗證，必須在 connect*() 之前調用

will_set()

1. will_set(topic, payload=None, qos=0, retain=False)

設置遺囑發送給MQTT代理，如果用戶端在沒有調用 disconnect() 的情況下斷開連接，則MQTT代理將會代表它發送該消息

topic

遺囑消息發佈的主題，不能為None或者空字元

payload

遺囑發送的消息內容，如果沒有賦值或者賦值為None，則將使用零長度的消息作為遺囑。傳遞int或者float將會被轉換為該數位的字串，如果想發送真正的int或者float資料，使用 struct.pack() 去創建

遺囑消息的服務品質等級，必須為0 or 1 or 2

retain

設置為True，MQTT代理保留最後一條消息，以便分發給消息發佈後的訂閱者

回呼函數

on_connect()

1. on_connect(client, userdata, flags, rc)

MQTT代理回應用戶端連接請求時( connect*() )調用

client

回檔返回的用戶端實例

userdata

Client() 或 user_data_set() 中設置的私有使用者資料

flags

MQTT代理發送的回應標識

連接結果

0：連接成功
1：連接被拒絕 - 協議版本
2：連接被拒絕 - 用戶端識別字無效
3：連接被拒絕 - 伺服器不可用
4：連接被拒絕 - 用戶名或密碼錯誤
5：連接被拒絕 - 未授權6-255：當前未使用

示例

1. def on_connect(client, userdata, flags, rc):

2. print("Connected with result code "+str(rc))

4. mqttc.on_connect = on_connect

on_disconnect()

當用戶端與MQTT代理斷開連接時 (disconnect()) 調用

1. on_disconnect(client, userdata, rc)

client

回檔返回的用戶端實例

userdata

Client() 或 user_data_set() 中設置的私有使用者資料

斷開結果，如果是 MQTT_ERR_SUCCESS(0)，則是回應disconnect()調用
如果是其它值，則是意外關閉

示例

1. def on_disconnect(client, userdata, rc):

2. if rc != 0:

3. print("Unexpected disconnection.")

5. mqttc.on_disconnect = on_disconnect

on_message()

1. on_message(client, userdata, message)

在用戶端收到已訂閱主題的消息，並且該消息沒有被主題篩檢程式 message_callback_add() 匹配時調用

client

回檔返回的用戶端實例

userdata

Client() 或 user_data_set() 中設置的私有使用者資料

message

MQTTMessage實例，包含 topic、payload、qos、retain

示例

1. def on_message(client, userdata, message):

2. print("Received message '" + str(message.payload) + "' on topic '"

3. + message.topic + "' with QoS " + str(message.qos))

5. mqttc.on_message = on_message

message_callback_add()

1. message_callback_add(sub, callback)

定義特定訂閱主題傳入的消息回檔，包括萬用字元，比如：用戶端訂閱了 sensor/#主題，一個回檔處理 sensor/temperature，另一個回檔處理 sensor/humidity

待過濾的主題，只能定義一個回檔

callback

回呼函數，與 on_message() 相同形式

示例

1. # 處理溫度消息回檔

2. def temperature_callback(client, userdata, message):

3. print(message.topic+" "+str(message.payload))

5. # 處理濕度消息回檔

6. def humidity_callback(client, userdata, message):

7. print(message.topic+" "+str(message.payload))

10. mqttc.subscribe('sensor/#')

11. mqttc.message_callback_add('sensor/temperature', temperature_callback)

12. mqttc.message_callback_add('sensor/humidity', humidity_callback)

message_callback_remove()

1. message_callback_remove(sub)

刪除先前註冊的主題/訂閱特定回檔

on_publish()

1. on_publish(client, userdata, mid)

當用戶端調用 publish() 發佈一條消息至MQTT代理後調用。Qos=1或2時，意味著用戶端和代理完成握手，Qos=0時，僅表示消息離開用戶端。

mid變數與從相應的 publish() 返回的mid變數匹配，以允許跟蹤傳出的消息。

即使 publish() 調用返回，也不總意味著消息已發送

on_subscribe()

1. on_subscribe(client, userdata, mid, granted_qos)

當MQTT代理回應訂閱請求時被調用

mid變數匹配從相應的 subscribe() 返回的mid變數

granted_qos

整數清單，它提供了代理為每個不同的訂閱請求授予的QoS級別

on_unsubscribe()

1. on_unsubscribe(client, userdata, mid)

當代理回應取消訂閱請求時調用

mid匹配從相應的 unsubscribe() 返回的mid變數

on_log()

1. on_log(client, userdata, level, buf)

當用戶端有日誌資訊時調用

level

消息嚴重性

MQTT_LOG_INFO
MQTT_LOG_NOTICE
MQTT_LOG_WARNING
MQTT_LOG_ERR
MQTT_LOG_DEBUG

該消息本身就在buf裡
可以與標準的Python logging同時使用，通過enable_logger()方法啟用

示例

1. import paho.mqtt.client as mq_tt

2. import time

3. import logging

6. logging.basicConfig(level='DEBUG', format='%(asctime)s [%(name)s:%(lineno)d] [%(levelname)s]- %(message)s')

9. def on_connect(client, userdata, flags, rc):

10. print("Connected with result code "+str(rc))

11. client.subscribe("topicTest/#")

12.

13.

14. def topic_one_callback(client, userdata, message):

15. print(message.topic+" "+str(message.payload))

16.

17.

18. def topic_two_callback(client, userdata, message):

19. print(message.topic+" "+str(message.payload))

20.

21.

22. mq_client = mq_tt.Client(client_id='www.cooooder.com')

23. mq_client.enable_logger()

24. mq_client.on_connect = on_connect

25. mq_client.message_callback_add("topicTest/one", topic_one_callback)

26. mq_client.message_callback_add("topicTest/two", topic_two_callback)

27. # 連接到EMQX Broker MQTT代理

28. mq_client.connect("127.0.0.1", 1883, 60)

29.

30. mq_client.loop_start()

出處：https://www.cooooder.com/archives/20210303

Paho Python MQTT Client – Subscribe With Examples

源自於 http://www.steves-internet-guide.com/subscribing-topics-mqtt-client/

'''

Python 範例程式已經根據可用 MQTT Broker 修改

程式先訂閱 house/bulb1 主題，然後發行 house/bulb1 此主題及內容

'''

import time

import paho.mqtt.client as mqtt

broker="broker.hivemq.com"

#broker_address="iot.eclipse.org"

# define callback

def on_message(client, userdata, message):

time.sleep(1)

print("received message =", str(message.payload.decode("utf-8")))

def on_subscribe(client, userdata, mid, granted_qos):

print("on_subscribe --> Subscribe with mid "+str(mid)+" received.")

print("on_subscribe --> Subscribe with granted_qos "+str(granted_qos)+" received.")

client = mqtt.Client("client-001") # create client object client1.on_publish = on_publish #assign function to callback client1.connect(broker,port) #establish connection client1.publish("house/bulb1","on")

######Bind function to callback

client.on_subscribe = on_subscribe

#####

print("connecting to broker ", broker)

client.connect(broker) # connect

client.loop_start() # start loop to process received messages

print("subscribing ")

#client.subscribe("alex9ufo/house/bulb1") # subscribe

client.subscribe([("alex9ufo/house/bulb3",2),("alex9ufo/house/bulb4",1),("alex9ufo/house/bulb5",0)])

print("publishing ")

client.publish("alex9ufo/house/bulb3", "on") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb4", "off") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb5", "on") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb3", "off") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb4", "on") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb5", "on") # publish

time.sleep(2)

client.disconnect() # disconnect

client.loop_stop() # stop loop

>>> %Run Subscribe_1.py

connecting to broker broker.hivemq.com

subscribing

publishing

on_subscribe --> Subscribe with mid 1 received.

on_subscribe --> Subscribe with granted_qos (2, 1, 0) received.

>>>

'''

Python 範例程式已經根據可用 MQTT Broker 修改

程式先訂閱 house/bulb1 主題，然後發行 house/bulb1 此主題及內容

'''

import time

import paho.mqtt.client as mqtt

broker="broker.hivemq.com"

#broker_address="iot.eclipse.org"

# define callback

def on_message(client, userdata, message):

time.sleep(1)

print("received message =", str(message.payload.decode("utf-8")))

def on_subscribe(client, userdata, mid, granted_qos):

print("on_subscribe --> Subscribe with mid "+str(mid)+" received.")

print("on_subscribe --> Subscribe with granted_qos "+str(granted_qos)+" received.")

######Bind function to callback

client.on_message = on_message

#####

print("connecting to broker ", broker)

client.connect(broker) # connect

client.loop_start() # start loop to process received messages

print("subscribing ")

#client.subscribe("alex9ufo/house/bulb1") # subscribe

client.subscribe([("alex9ufo/house/bulb3",2),("alex9ufo/house/bulb4",1),("alex9ufo/house/bulb5",0)])

print("publishing ")

client.publish("alex9ufo/house/bulb3", "on") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb4", "off") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb5", "on") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb3", "off") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb4", "on") # publish

time.sleep(2)

client.publish("alex9ufo/house/bulb5", "on") # publish

time.sleep(2)

client.disconnect() # disconnect

client.loop_stop() # stop loop

>>> %Run Subscribe_1.py

connecting to broker broker.hivemq.com

subscribing

publishing

received message = on

received message = off

received message = on

received message = off

received message = on

>>>

Paho Python MQTT Client – Publish With Examples

源自於 http://www.steves-internet-guide.com/publishing-messages-mqtt-client/

Publishing a Message

To publish a message you need to:

Create a client object.
Create a client connection.
publish the message
Examine the return code of the publish request
Examine the publish acknowledgement using the on_publish callback

Example code:
import paho.mqtt.client as paho
broker="192.168.1.184"
port=1883
def on_publish(client,userdata,result):             #create function for callback
    print("data published \n")
    pass
client1= paho.Client("control1")                           #create client object
client1.on_publish = on_publish                          #assign function to callback
client1.connect(broker,port)                                 #establish connection
ret= client1.publish("house/bulb1","on")                   #publish

Note 1: you don’t appear to need a client loop to process the on_publish callback.

Note2: When you publish a message the publish method returns a tuple (result, mid).

The result is the error code. A result of 0 indicates success.

The mid value is an integer that corresponds to the published message number as assigned by the client.

The mid value can be used with the on_publish callback to check that the messages was published even when publishing with a qos of 0.

If you publish with a qos of 0 the published message has a mid of 0 but internally it has a mid just like qos 1,2 messages.
So on the broker you see a mid of 0 but on the client you see an incrementing mid.

On_publish Callback

When the message has been published to the Broker an acknowledgement is sent that results in the on_publish callback being called.

The on_publish callback function must receive three parameters

on_publish(client, userdata, mid)

The client is the client object, and is useful when you have multiple clients that are publishing data.

The userdata is user defined data which isn’t normally used.

The mid value is the message id and can be used with the mid value returned from the publish method to check that a particular message has been published.

In the screen shot below I have printed the mid value from the publish message and on publish callback.

You can see that the numbers match which indicated that both messages were published OK

import paho.mqtt.client as mqtt

broker="broker.hivemq.com"

port=1883

def on_publish(client,userdata,result): #create function for callback

print("Published message.result : " + str(result))

print("data published \n")

pass

client1= mqtt.Client("control1") #create client object

client1.on_publish = on_publish #assign function to callback

client1.connect(broker,port) #establish connection

ret= client1.publish("alex9ufo/house/bulb1","on",qos=0, retain=False) #publish

>>> %Run Publish_1.py

Published message.result : 1

data published

>>>

import paho.mqtt.client as mqtt

broker="broker.hivemq.com"

port=1883

def on_publish(client,userdata,mid): #create function for callback

print("Published message.mid: " + str(mid))

print("data published \n")

pass

client1= mqtt.Client("control1") #create client object

client1.on_publish = on_publish #assign function to callback

client1.connect(broker,port) #establish connection

ret= client1.publish("alex9ufo/house/bulb1","off",qos=0, retain=False) #publish

>>> %Run Publish_2.py

Published message.mid: 1

data published

'''

Python 範例程式已經根據可用 MQTT Broker 修改

程式先訂閱 house/bulb1 主題，然後發行 house/bulb1 此主題及內容

'''

import time

import paho.mqtt.client as mqtt

broker="broker.hivemq.com"

#broker_address="iot.eclipse.org"

# define callback

def on_message(client, userdata, message):

time.sleep(1)

print("received message =", str(message.payload.decode("utf-8")))

######Bind function to callback

client.on_message = on_message

#####

print("connecting to broker ", broker)

client.connect(broker) # connect

client.loop_start() # start loop to process received messages

print("subscribing ")

client.subscribe("alex9ufo/house/bulb1") # subscribe

print("publishing ")

client.publish("alex9ufo/house/bulb1", "on") # publish

time.sleep(5)

client.publish("alex9ufo/house/bulb1", "off") # publish

time.sleep(3)

client.disconnect() # disconnect

client.loop_stop() # stop loop

>>> %Run Publish_3.py

connecting to broker broker.hivemq.com

subscribing

publishing

received message = on

received message = off

import paho.mqtt.client as mqtt

import time

# Define event callbacks

UserName="alex9ufo"

Password="alex9981"

hostname="broker.hivemq.com"

port=1883

RootTopic="alex9ufo/house"

def on_connect(client, userdata, rc):

if rc == 0:

print("on_connect --> Connected successfully.")

else:

print("Connection failed. rc= "+str(rc))

def on_publish(client, userdata, mid):

print("on_publish --> Message "+str(mid)+" published.")

def on_subscribe(client, userdata, mid, granted_qos):

print("on_subscribe --> Subscribe with mid "+str(mid)+" received.")

def on_message(client, userdata, msg):

print("on_message --> Message received on topic "+msg.topic+" with QoS "+str(msg.qos)+" and payload "+msg.payload)

mqttclient = mqtt.Client()

# Assign event callbacks

mqttclient.on_connect = on_connect

mqttclient.on_message = on_message

mqttclient.on_publish = on_publish

mqttclient.on_subscribe = on_subscribe

# Connect

mqttclient.username_pw_set(UserName, Password)

mqttclient.connect(hostname, port)

# Start subscription

mqttclient.subscribe(RootTopic)

time.sleep(4) # wait

# Publish a message

mqttclient.publish(RootTopic, " MQTT Message --> Hello World!")

time.sleep(4) # wait

mqttclient.loop_stop() #stop the loop

>>> %Run Publish_4.py

on_publish --> Message 2 published.

>>>

2022年12月27日星期二

MQTT and Python For Beginners -Troubleshoot using Logging

MQTT and Python For Beginners -Troubleshoot using Logging

源自於 http://www.steves-internet-guide.com/mqtt-python-beginners-course/

Troubleshoot using Logging (使用日誌記錄進行故障排除)

To help troubleshoot your applications you can use the built in client logging callback.

import paho.mqtt.client as mqtt #import the client1

import time

############

def on_message(client, userdata, message):

print("callback functions to Process any Messages Start a loop to check for callback messages.")

print("message received -->" ,str(message.payload.decode("utf-8")))

print("message topic=",message.topic)

print("message qos=",message.qos)

print("message retain flag=",message.retain)

########################################

def on_log(client, userdata, level, buf):

print("log: ",buf)

########################################

broker_address="broker.hivemq.com"

#broker_address="iot.eclipse.org"

print("creating new instance")

client = mqtt.Client("P1") #create new instance

client.on_message=on_message #attach function to callback

client.on_log=on_log

print("connecting to broker")

client.connect(broker_address) #connect to broker

client.loop_start() #start the loop

print("Subscribing to topic","house/bulbs/bulb1")

client.subscribe("house/bulbs/bulb1")

print("Publishing message to topic","house/bulbs/bulb1")

client.publish("house/bulbs/bulb1","OFF")

time.sleep(4) # wait

client.loop_stop() #stop the loop

>>> %Run -c $EDITOR_CONTENT

creating new instance

connecting to broker

log: Sending CONNECT (u0, p0, wr0, wq0, wf0, c1, k60) client_id=b'P1'

Subscribing to topic house/bulbs/bulb1

log: Sending SUBSCRIBE (d0, m1) [(b'house/bulbs/bulb1', 0)]

Publishing message to topic house/bulbs/bulb1

log: Sending PUBLISH (d0, q0, r0, m2), 'b'house/bulbs/bulb1'', ... (3 bytes)

log: Received CONNACK (0, 0)

log: Received SUBACK

log: Received PUBLISH (d0, q0, r0, m0), 'house/bulbs/bulb1', ... (3 bytes)

callback functions to Process any Messages Start a loop to check for callback messages.

message received --> OFF

message topic= house/bulbs/bulb1

message qos= 0

message retain flag= 0

>>>

訂閱：文章 (Atom)

2022年12月28日 星期三

Paho MQTT Python Client 使用手册

Paho MQTT Python Client 使用手册

Paho Python MQTT Client – Subscribe With Examples

Paho Python MQTT Client – Publish With Examples

Publishing a Message

On_publish Callback

2022年12月27日 星期二

MQTT and Python For Beginners -Troubleshoot using Logging

源自於 http://www.steves-internet-guide.com/mqtt-python-beginners-course/

Troubleshoot using Logging (使用日誌記錄進行故障排除)

Node-Red --> MQTT --> Fuxa

2022年12月28日星期三

2022年12月27日星期二