AWS IoT Jobs library

The AWS IoT Jobs library helps you notify connected IoT devices of a pending Job. A Job can be used to manage your fleet of devices, update firmware and security certificates on your devices, or perform administrative tasks such as restarting devices and performing diagnostics. It interacts with the AWS IoT Jobs service using MQTT, a lightweight publish-subscribe protocol. This library provides a convenience API to compose and recognize the MQTT topic strings used by the Jobs service. The library is written in C compliant with ISO C90 and MISRA C:2012, and is distributed under the MIT Open Source License.

This library has gone through code quality checks including verification that no function has a GNU Complexity score over 8, and checks against deviations from mandatory rules in the MISRA coding standard . Deviations from the MISRA C:2012 guidelines are documented under MISRA Deviations. This library has also undergone both static code analysis from Coverity, and validation of memory safety with the CBMC bounded model checker.

See memory requirements for this library here.

AWS IoT Jobs v1.3.0 source code is part of the FreeRTOS 202210.00 LTS release.

AWS IoT Jobs v1.1.0 source code is part of the FreeRTOS 202012.01 LTS release.

Building the Jobs library

A compiler that supports C90 or later such as gcc is required to build the library.

Given an application in a file named example.c, gcc can be used like so:

gcc -I source/include example.c source/jobs.c -o example

gcc can also produce an object file to be linked later:

gcc -I source/include -c source/jobs.c

CBMC

To learn more about CBMC and proofs specifically, review the training material here.

The test/cbmc/proofs directory contains CBMC proofs.

In order to run these proofs you will need to install CBMC and other tools by following the instructions here.

Reference example

The AWS IoT Device SDK for Embedded C repository contains a demo using the jobs library on a POSIX platform. https://github.com/aws/aws-iot-device-sdk-embedded-C/tree/main/demos/jobs/jobs_demo_mosquitto

Documentation

Existing Documentation

For pre-generated documentation, please see the documentation linked in the locations below:

Location

AWS IoT Device SDK for Embedded C

FreeRTOS.org

Note that the latest included version of the AWS IoT Jobs library may differ across repositories.

Generating Documentation

The Doxygen references were created using Doxygen version 1.9.2. To generate the Doxygen pages, please run the following command from the root of this repository:

doxygen docs/doxygen/config.doxyfile

Building unit tests

Checkout Unity Submodule

By default, the submodules in this repository are configured with update=none in .gitmodules to avoid increasing clone time and disk space usage of other repositories that submodule this repository.

To build unit tests, the submodule dependency of Unity is required. Use the following command to clone the submodule:

git submodule update --checkout --init --recursive --test/unit-test/Unity

Platform Prerequisites

  • For running unit tests

    • C90 compiler like gcc

    • CMake 3.13.0 or later

    • Ruby 2.0.0 or later is additionally required for the Unity test framework (that we use).

  • For running the coverage target, lcov is additionally required.

Steps to build Unit Tests

  1. Go to the root directory of this repository. (Make sure that the Unity submodule is cloned as described above.)

  2. Create build directory: mkdir build && cd build

  3. Run cmake while inside build directory: cmake -S ../test

  4. Run this command to build the library and unit tests: make all

  5. The generated test executables will be present in build/bin/tests folder.

  6. Run ctest to execute all tests and view the test run summary.

Contributing

See CONTRIBUTING.md for information on contributing.