3/10/20241物聯(lián)網(wǎng)技術(shù)及應(yīng)用發(fā)布及訂閱消息

3/10/20242發(fā)布及訂閱消息樹莓派端訂閱主題，本地PC端發(fā)布主題3/10/20243發(fā)布及訂閱消息（1）本地PC機(jī)端發(fā)布主題result=client.publish(topic=topic,payload=msg,qos=0,retain=True)ifresult[0]==0:print("Send{0}totopic{1}".format(msg,topic))else:print("Failedtosendmessage{0}totopic{1}".format(msg,topic))3/10/20244發(fā)布及訂閱消息

info={'msg1':'Helloworld','msg2':'msg{0}'.format(random.randint(0,1000))}msg=json.dumps(info)MQTT只傳輸字符串信息，我們定義topic="pi4b/test"，發(fā)布信息到該主題下，信息內(nèi)容為兩條，分別為“helloworld”和msg0~1000之間的一個(gè)隨機(jī)數(shù)，并轉(zhuǎn)存為json格式。3/10/20245發(fā)布及訂閱消息3/10/20246發(fā)布及訂閱消息（2）樹莓派智能車端訂閱主題；subscribe(topic=topic,qos=0)defon_message(client,userdata,msg):data=json.loads(msg.payload)#data=字典#payload=json數(shù)據(jù)print("Receivedmessagefromtopic{0}".format(msg.topic))print("Themessagehave{0}information".format(len(data)))print("Theinformationis'{0}'".format(data))3/10/20247發(fā)布及訂閱消息3/10/20248Thankyou3/10/20249物聯(lián)網(wǎng)技術(shù)及應(yīng)用服務(wù)器web顯示

3/10/202410服務(wù)器web顯示3/10/202411服務(wù)器web顯示華為云的官網(wǎng)地址為：。3/10/202412服務(wù)器web顯示創(chuàng)建一個(gè)實(shí)例單元：3/10/202413服務(wù)器web顯示要使用平臺(tái)查看樹莓派端連接的DHT11設(shè)備上報(bào)的數(shù)據(jù)信息，并對(duì)設(shè)備進(jìn)行管理控制，就需要完成以下步驟：3/10/202414服務(wù)器web顯示（1）創(chuàng)建產(chǎn)品。3/10/202415服務(wù)器web顯示點(diǎn)擊創(chuàng)建產(chǎn)品后需設(shè)置字段包含如下：3/10/202416服務(wù)器web顯示自定義開發(fā)產(chǎn)品模型3/10/202417服務(wù)器web顯示新增屬性3/10/202418服務(wù)器web顯示（2）注冊(cè)設(shè)備3/10/202419服務(wù)器web顯示設(shè)備屬性和創(chuàng)建3/10/202420Thankyou3/10/202421物聯(lián)網(wǎng)技術(shù)及應(yīng)用物聯(lián)網(wǎng)云平臺(tái)連接真實(shí)設(shè)備

3/10/202422物聯(lián)網(wǎng)云平臺(tái)連接真實(shí)設(shè)備defconnect_mqtt():defon_connect(client,userdata,flags,rc):ifrc==0:print("Connectedtobrokersuccessfully!")else:print("Failedtoconnectbroker,returncode{0}".format(rc))client=mqtt.Client(client_id=get_client_id(device_id))client.on_connect=on_connectclient.username_pw_set(device_id,get_password(secret))client.connect(server_ip,port,keepalive)returnclient連接華為云物聯(lián)網(wǎng)平臺(tái)的服務(wù)器：3/10/202423物聯(lián)網(wǎng)云平臺(tái)連接真實(shí)設(shè)備華為云物聯(lián)網(wǎng)平臺(tái)服務(wù)器設(shè)備狀態(tài)：3/10/202424物聯(lián)網(wǎng)云平臺(tái)連接真實(shí)設(shè)備樹莓派運(yùn)行連接代碼：3/10/202425物聯(lián)網(wǎng)云平臺(tái)連接真實(shí)設(shè)備3/10/202426Thankyou3/10/202427物聯(lián)網(wǎng)技術(shù)及應(yīng)用設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)

3/10/202428設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)設(shè)備屬性發(fā)布：3/10/202429設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)@propertydefservice_property(self):returnself.__services_propertiesclassServicesProperties:def__init__(self):self.__services_properties=list()

defadd_service_property(self,service_id,property,value):service_property_dict={"service_id":service_id,"properties":{property:value}}self.__services_properties.append(service_property_dict)

定義屬性類：3/10/202430設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)指定的Topic為：topic=r'$oc/devices/'+str(device_id)+r'/sys/properties/report'defreport_properties(service_properties,qos):print("......Devicereportingproperties......")topic=r'$oc/devices/'+str(device_id)+r'/sys/properties/report'payload={"services":service_properties}payload=json.dumps(payload)client.publish(topic,payload,qos=qos)print("-----------------Devicereportpropertiescompleted-----------------")編寫屬性上報(bào)函數(shù)：3/10/202431設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)whileTrue: humidity,temperature=Adafruit_DHT.read_retry(11,dht11pin) print('Temp:{0:0.1f}CHumidity:{1:0.1f}%'.format(temperature,humidity)) service_property=ServicesProperties() service_property.add_service_property(service_id="smarthome", property='temperature',value=temperature) service_property.add_service_property(service_id="smarthome", property='humidity',value=humidity) report_properties(service_properties=service_property.service_property,qos=1)

time.sleep(15)溫濕度數(shù)據(jù)實(shí)時(shí)采集溫度數(shù)據(jù)添加濕度數(shù)據(jù)添加溫濕度數(shù)據(jù)發(fā)布3/10/202432設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)樹莓派端運(yùn)行代碼上報(bào)日志顯示：3/10/202433設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)云服務(wù)器接收顯示：3/10/202434設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)設(shè)置歷史數(shù)據(jù)查看步驟1：3/10/202435設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)設(shè)置歷史數(shù)據(jù)查看步驟2：3/10/202436設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)設(shè)置歷史數(shù)據(jù)查看步驟3：3/10/202437設(shè)備數(shù)據(jù)上報(bào)云平臺(tái)設(shè)置歷史數(shù)據(jù)查看步驟4：3/10/2