Drogue IoT Cloud – Testing

This project hosts a testing suite for testing a full Drogue IoT Cloud installation end-to-end.

Running

Requirements

The following utilities must be installed and available in your PATH:

• Geckodriver: https://github.com/mozilla/geckodriver/relases
• drg: https://github.com/drogue-cloud/drg/releases
• httpie: https://github.com/httpie/httpie/releases

Run the tests

You will need an installation of Drogue Cloud. If you are using Minikube or Kind, you can then run:

make CERT_BASE=/path/to/drogue-cloud/build/certs/

Assuming you deployed drogue-cloud from /path/to/drogue-cloud.

Otherwise, you need to pass in the application domain:

make DOMAIN=-my.apps.domain.cluster.tld.

Or explicitly the console and API URL:

make CONSOLE_URL=https://my-console.tld. API_URL=https://my-api.tld.

You can run individual tests, by passing them in using the TESTS variable:

make … TESTS=tests::http::telemetry::test_send_telemetry_pass::version_3

Rust and testing

Rust and testing isn't (yet) as easy as it is with e.g. JUnit. The following sections document some struggles and how we deal with them.

Setup and teardown

Setup and teardown of resources, especially async ones (like the web driver) are not supported by the default Rust test runner.

For this, we use test-context. We can setup and tear down the resources, driven by the test-context crate, which also supports async_trait and so we can easily deconstruct the web driver.

Parametrized tests

Some tests require to be run with different parameter sets. Like the MQTT integration, we can run this with MQTT 3.1.1 and 5.0 in both structured and binary mode.

Instead of defining each test three times, we use the rstest crate, which allows to define something like a test matrix. We don't use rstest-reuse right now, as it has some limitations, which might get resolved in the near future.

Unfortunately, rstest does not support custom/async teardown of resources. And so, we need to rely on the Drop trait and do some blocking/async magic in there, do properly destruct the web driver. This requires rstest based tests to be run with the "multi-threaded" Tokio runtime. Which needs to be explicitly enabled with tests.

Hopefully, this will be fixed too in rstest, which would allow us to switch from test-context to rstest and drop the Drop workaround.