wasmcloud-test-util

This repository contains utilities for writing tests for the wasmCloud ecosystem.

This crate provides utilities for:

• Manipulating a wasmCloud host programmatically
• Starting/stopping workloads (i.e. providers and components)
• Dealing with OS-level dependencies (ex. random ports)
• ... and more

This crate is meant to be used by programs, utilities and infrastructure targeting the wasmCloud platform.

Installation

To use wasmcloud-test-util in your project, you can add it via cargo add as a test (development) dependency:

cargo add --dev wasmcloud-test-util

Or include the following in your Cargo.toml:

wasmcloud-test-util = "0.13.0"

Features

wasmcloud-test-util comes with the following features:

Using wasmcloud-test-util

wasmcloud-test-util does not provide a prelude, but instead exports types as needed under appropriate modules.

use tokio::time::Duration;

use wasmcloud_test_util::control_interface::ClientBuilder;
use wasmcloud_test_util::lattice::link::{assert_advertise_link, assert_remove_link};
use wasmcloud_test_util::nats::wait_for_nats_connection;
use wasmcloud_test_util::provider::StartProviderArgs;
use wasmcloud_test_util::testcontainers::{AsyncRunner as _, ImageExt, NatsServer};
use wasmcloud_test_util::{
    assert_config_put, assert_scale_component, assert_start_provider, WasmCloudTestHost,
};

#[tokio::test]
async fn example_test() -> anyhow::Result<()> {
    // Start NATS
    let nats_container = NatsServer::default()
        .with_cmd(["--jetstream"])
        .start()
        .await
        .expect("failed to start nats-server container");
    let nats_port = nats_container
        .get_host_port_ipv4(4222)
        .await
        .expect("should be able to find the NATS port");
    let nats_url = format!("nats://127.0.0.1:{nats_port}");

    // Build a wasmCloud host (assuming you have a local NATS server running)
    let lattice = "default";
    let host = WasmCloudTestHost::start(nats_url, lattice).await?;

    // Once you have a host (AKA a single-member wasmCloud lattice), you'll want a NATS client
    // which you can use to control the host and the lattice:
    let nats_client = async_nats::connect(nats_url).await?;
    let ctl_client = ClientBuilder::new(nats_client)
        .lattice(host.lattice_name().to_string())
        .build();

    // Now that you have a control client, you can use the `assert_*` functions to perform actions on your host:
    assert_config_put(
        &ctl_client,
        "test-config",
        [("EXAMPLE_KEY".to_string(), "EXAMPLE_VALUE".to_string())],
    )
    .await?;

    assert_scale_component(
        &ctl_client,
        &host.host_key(),
        "ghcr.io/wasmcloud/components/http-jsonify-rust:0.1.1",
        "example-component",
        None,
        1,
        Vec::new(),
        Duration::from_secs(10),
    )
    .await?;

    // ... your test logic goes here ...

    Ok(())
}

Contributing

Have a change that belongs be in wasmcloud-test-util? Please feel free to file an issue and/or join us on the wasmCloud slack!