temporal workflow bootstrapped from a single instruction "browse the temporal.io docs to write a simple Golang workflow for sending an email at 9am PT every day, skipping a day when a signal has been sent to skip the day" on the livestream https://twitter.com/swyx/status/1778641185193730488

devin-temporal-workflow.go

package main

import (
	"context"
	"log"
	"time"

	"go.temporal.io/sdk/client"
	"go.temporal.io/sdk/worker"
	"go.temporal.io/sdk/workflow"
)

// EmailWorkflow is the definition for the workflow responsible for sending emails.
func EmailWorkflow(ctx workflow.Context) error {
	// Define the signal channel for skipping a day.
	var skipDaySignal string
	skipChannel := workflow.GetSignalChannel(ctx, "SkipDaySignal")
	workflow.Go(ctx, func(ctx workflow.Context) {
		skipChannel.Receive(ctx, &skipDaySignal)
	})

	// Define the activity options.
	ao := workflow.ActivityOptions{
		StartToCloseTimeout: 10 * time.Minute,
	}
	ctx = workflow.WithActivityOptions(ctx, ao)

	// Run the email sending activity daily unless a skip signal is received.
	for {
		// Check if today is a skip day.
		if skipDaySignal == "skip" {
			// Reset the signal for the next day.
			skipDaySignal = ""
			// Skip today's email.
			workflow.Sleep(ctx, 24*time.Hour)
			continue
		}

		// Send the email.
		err := workflow.ExecuteActivity(ctx, SendEmailActivity).Get(ctx, nil)
		if err != nil {
			return err
		}

		// Wait for the next day.
		workflow.Sleep(ctx, 24*time.Hour)
	}

	return nil
}

// SendEmailActivity is a placeholder for the activity that sends the email.
func SendEmailActivity(ctx context.Context) error {
	// Simulated email sending logic.
	log.Println("Sending email...")
	// Here you would integrate with an SMTP server or an email service provider's API.
	// For simulation purposes, we're just logging the action.
	return nil
}

func main() {
	// Create the Temporal client.
	c, err := client.NewClient(client.Options{})
	if err != nil {
		log.Fatalln("Error creating Temporal client:", err)
	}
	defer c.Close()

	// Register the workflow and activity with the worker.
	w := worker.New(c, "email-tasks", worker.Options{})
	w.RegisterWorkflow(EmailWorkflow)
	w.RegisterActivity(SendEmailActivity)

	// Start the worker to listen to the task queue.
	err = w.Start()
	if err != nil {
		log.Fatalln("Error starting worker:", err)
	}
}

it even got a local temporal cluster running!