resonate-basic-ephemeral-world-usage-go

Resonate Basic Ephemeral World Usage — Go

Version note. The Go SDK's first tagged release is 0.1.0. The tag is 0.1.0, not v0.1.0, so go get …@latest does not resolve to it (it walks main instead and returns a newer pseudo-version). Pin the tag explicitly — see Install below. APIs may still change before a 1.0. Every code block here is verified against the 0.1.0 tag source and the resonatehq-examples/*-go repos.

Overview

The ephemeral world is wherever your Go program starts: main(), an HTTP handler, a CLI entry point, a background goroutine. You use a *resonate.Resonate instance 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 only. The Durable World (Context APIs inside workflow functions) is covered in resonate-basic-durable-world-usage-go.

Install

go get github.com/resonatehq/[email protected]

The tag on GitHub is 0.1.0 (no v prefix), so this is not the same as go get …@latest — @latest walks main past the tag and resolves to a newer pseudo-version instead. Requesting the tag by name resolves correctly: the module proxy mints the pseudo-version pinned to that exact commit (verify with curl -s https://proxy.golang.org/github.com/resonatehq/resonate-sdk-go/@v/0.1.0.info). Pin a later commit the same way (@<short-sha>) for reproducible builds ahead of the next tag.

Core imports:

import (
    resonate "github.com/resonatehq/resonate-sdk-go"
    "github.com/resonatehq/resonate-sdk-go/localnet"  // zero-dependency dev
    "github.com/resonatehq/resonate-sdk-go/httpnet"   // named worker groups
)

Basic Shape

A complete one-file program: register, run, read, stop.

package main

import (
    "context"
    "fmt"
    "log"
    "time"

    resonate "github.com/resonatehq/resonate-sdk-go"
)

type GreetArgs struct {
    Name string `json:"name"`
}

func greet(_ *resonate.Context, args GreetArgs) (string, error) {
    return fmt.Sprintf("hello, %s!", args.Name), nil
}

func main() {
    r, err := resonate.New(resonate.Config{URL: "http://localhost:8001"})
    if err != nil {
        log.Fatalf("resonate.New: %v", err)
    }
    defer func() { _ = r.Stop() }()

    greetFn, err := resonate.Register(r, "greet", greet)
    if err != nil {
        log.Fatalf("Register: %v", err)
    }

    ctx := context.Background()
    id := fmt.Sprintf("hello-%d", time.Now().UnixNano())

    h, err := greetFn.Run(ctx, id, GreetArgs{Name: "world"})
    if err != nil {
        log.Fatalf("Run: %v", err)
    }

    out, err := h.Result(ctx)
    if err != nil {
        log.Fatalf("Result: %v", err)
    }
    fmt.Println(out) // hello, world!
}