IoT Platform:Use the Paho MQTT library for Rust to connect a device to IoT Platform

Usage notes

In this topic, the permissions of a common user are used to perform all operations. If you want to perform specific operations that require administrator permissions, run the sudo command.

Prerequisites

A product and a device are created in an instance in the IoT Platform console. A device certificate and an MQTT endpoint are obtained. The certificate information includes the ProductKey, DeviceName, and DeviceSecret. For more information, see the following topics:

• View the endpoint of an instance

• Create a product

• Create a device

Prepare a development environment

• Ubuntu 18.04

• Cargo 1.61.0 or later

• If you use Linux, run the following command to install Cargo to manage dependencies.

  sudo apt-get install cargo cmake

Connect a device to IoT Platform

1. Download the package that contains the sample code and decompress the package to the aiot-rust-demo directory. The following table describes the files that are decompressed to the directory.

   File	Description
   src/mqtt-basic-demo/main.rs	This file contains the logic code that is used to connect a device to IoT Platform and enable communications.
   Cargo.toml	The description file of the project.

2. In the src/mqtt-basic-demo/main.rs file, replace the values of the product_key, device_name, , and device_secret parameters with your device certificate information.

   let product_key = "gb80*****";
   let device_name = "mqtt_******o";
   let timestamp = "2524****000";
   let device_secret = b"f***********************b";
   let host = "tcp://iot-060axxxx.mqtt.iothub.aliyuncs.com:1883"

3. Run the cargo build command to compile your project. An output that is similar to the following information is returned.

      Compiling hex-literal v0.3.4
      Compiling hmac-sha256 v0.1.7
      Compiling openssl-src v111.24.0+1.1.1s
      Compiling cmake v0.1.49
      Compiling slab v0.4.7
      Compiling openssl-sys v0.9.80
      Compiling paho-mqtt-sys v0.8.0 (https://github.com/eclipse/paho.mqtt.rust.git?branch=master#8e1f7342)
      Compiling concurrent-queue v2.1.0
      Compiling crossbeam-channel v0.5.6
      Compiling async-channel v1.8.0
      Compiling futures-macro v0.3.25
      Compiling thiserror-impl v1.0.38
      Compiling futures-executor v0.3.25
      Compiling futures v0.3.25
      Compiling paho-mqtt v0.12.0 (https://github.com/eclipse/paho.mqtt.rust.git?branch=master#8e1f7342)
      Compiling mqtt-example v0.1.0 
       Finished dev [unoptimized + debuginfo] target(s) in 20.83s

4. Run the ./target/debug/mqtt_basic_demo command to execute the project. An output that is similar to the following information is returned.

   starting Alibaba iot demo...
   subscribed to topic:=/gb80sxxxx/mqtt_basic_demo/user/get
   published to topic:=/gb80sxxxx/mqtt_basic_demo/user/update
   start receiving...