resonate-basic-ephemeral-world-usage-rust

Resonate Basic Ephemeral World Usage — Rust

SDK note. The Resonate Rust SDK is in active development (resonate-sdk v0.6.0, published on crates.io). APIs may change between releases. Treat every code example as a moving target until the SDK reaches 1.0.

Overview

The ephemeral world is anywhere your Rust program starts: main(), an Axum or Actix handler, a CLI entry point, a background service. You use the Resonate client to register durable functions and invoke them top-level. Once an invocation starts, it crosses into the durable world and Resonate guarantees its completion — retries on failure, resumes after crashes, continues across process restarts.

This skill covers the Client API surface. The Durable World (Context APIs inside #[resonate::function]) lives in resonate-basic-durable-world-usage-rust.

Install

The Rust SDK is published on crates.io. Add to your Cargo.toml:

[dependencies]
resonate = { package = "resonate-sdk", version = "0.6" }
tokio = { version = "1", features = ["full"] }
serde = { version = "1", features = ["derive"] }

Most programs also want serde_json for the json!(...) macro used in the promises API.

use resonate::prelude::*;

Initialize

Local mode (zero-dependency; in-memory promise store):

use resonate::prelude::*;

let resonate = Resonate::local();

Remote mode (connects to a Resonate server):

use resonate::prelude::*;

let resonate = Resonate::new(ResonateConfig {
    url: Some("http://localhost:8001".into()),
    ..Default::default()
});

With explicit worker group + auth token:

let resonate = Resonate::new(ResonateConfig {
    url: Some("https://resonate.example.com".into()),
    group: Some("workers".into()),
    token: std::env::var("RESONATE_TOKEN").ok(),
    ..Default::default()
});

The SDK reads environment variables when config fields are not set:

• RESONATE_URL — full base URL
• RESONATE_HOST + RESONATE_PORT — alternate construction
• RESONATE_TOKEN — JWT for authenticated servers
• RESONATE_SCHEME — http by default
• RESONATE_PREFIX — prepended to all promise + task IDs for multi-tenant namespacing