Introduce in detail how to communicate with Huawei cloud IOT through mqtt protocol

One 、 Create products

First, log in to the official website address of Huawei cloud ： Huawei cloud official website
After entering the main page , Search the Internet of things

choice lotDA Get into

Click use now

Then click the platform access address on the overview page
From here, you can see Huawei cloud Internet of things MQTT The protocol port number is also the domain name address

Then click create product in the product column

Follow the prompts to fill in the information

Two 、 Device registration

Click register device in the column of all devices of the product

Follow the prompts to fill in the information

After setting, information will be generated , Download and save ！
This is my device information

Equipment information ：
Resource space ：DefaultApp_62afp4qr
Device identifier （device_id）:aaron_1
Equipment identification code ：sep8266_iot
Device key （secret）：1531149131263
{
“device_id”: “aaron_1”,
“secret”: “1531149131263”
}

3、 ... and 、 Product model definition

Click to view the devices created in the product
Select a custom model

Add service

The next step is to add attributes , Attribute is the data type uploaded by the sensor , Data to be displayed ; According to the number of sensors 、 The type can be defined by itself .

Four 、 Generate MQTT Login key

After creating products and devices , We're going to use MQTT Protocol to log in to Huawei ECS , Detailed official address ： Use MQTT.fx Commissioning

This is parameter resolution
MQTT Device login key generation address ： Online generation MQTT The key
Fill in the information downloaded before , Include device_id and secret.

Here we get it MQTT Parameters of protocol device login .

5、 ... and 、 Use MQTT Client software login

up to now , All parameters have been obtained , Next, use MQTT The client logs into Huawei cloud to communicate .
open MQTT The end of the service , Specific download and transfer ：MQTT client v2.4( agreement 3.1.1).exe
The domain name of Huawei cloud Internet of things platform is :
a161a58a78.iot-mqtts.cn-north-4.myhuaweicloud.com
Of Huawei's cloud Internet of things platform IP The address is : 121.36.42.100

MQTT client 、 user name 、 The login password has just been obtained .
Those who don't understand can see the end , I've summed it up .

After connection , Return to the cloud platform , You can see that the device is online . It indicates that the device has been successfully connected .

6、 ... and 、 Report data

After successful connection , Next, we will report the data , Official course address ：MQTT Report data

The format of the reported data is introduced in detail .
About service_id and properties We can check on the cloud platform .
Click View in the column of all devices

In the device shadow column, you can see that the service and attribute correspond to each other service_id and properties
I have marked it .

Hua Wei Yun lot Platform MQTT Format of protocol subscription topic ： Format ：$oc/devices/{device_id}/sys/messages/down
for example ：$oc/devices/aaron_1/sys/messages/down

Hua Wei Yun lot platform MQTT Format of agreement publishing topic ：
Format ：$oc/devices/{device_id}/sys/properties/report
for example ：$oc/devices/aaron_1/sys/properties/report

An example of a device publishing information to Huawei cloud platform ： {"services": [{"service_id": "DHT11","properties":{"DHT11-T":50}}]}

stay MQTT The client fills in the corresponding parameters , Then subscribe and publish topics , You can see the successful subscription information and sending data on the right .

Back to cloud platform , You can see the data information we reported .

Here we are , The device data has been reported successfully ！

 Summarize the information ：
 Data generated by my device ：
ClientId/device_id：aaron_1
DeviceService/sercret：1531149131263

MQTT The account generates information online ：
MQTT client ID/Clientld：aaron_1_0_0_2022070108
MOTT user name /Username：aaron_1
MQTT The login password /Password：66459ff563a64c15e817e1414e292c44c1e464ed91bdb450a4ef15f3ed84f6a0

 Hua Wei Yun iot Platform MQTT Server address information ：
 port ：1883
 domain name ：219102c9fe.iot-mqtts.cn-north-4.myhuaweicloud.com
ip Address ：121.36.42.100

 Hua Wei Yun lot Platform MQTT Format of protocol subscription topic ：
 Format ：$oc/devices/{
    device_id}/sys/messages/down
 for example ：$oc/devices/aaron_1/sys/messages/down

 Hua Wei Yun lot platform MQTT Format of agreement publishing topic ：
 Format ：$oc/devices/{
    device_id}/sys/properties/report
 for example ：$oc/devices/aaron_1/sys/properties/report

 An example of a device publishing information to Huawei cloud platform ：{
    "services": [{
    "service_id": "DHT11","properties":{
    "DHT11-T":50}}]}