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

Usage notes

All operations in this topic use common user permissions. If an operation requires 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

• On Linux, run the following command to install Cargo and manage dependencies.

  sudo apt-get install cargo cmake

Connect a device to IoT Platform

1. Download the sample code package and decompress it to the aiot-rust-demo directory. The directory contains the following files.

   File	Description
   src/mqtt-basic-demo/main.rs	The logic code for connecting a device to IoT Platform and enabling communications.
   Cargo.toml	The project manifest file.

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 the project. The following sample output 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 run the project. The following sample output 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...