Workflows & activities

Workflows orchestrate; activities do. The workflow method describes the durable control flow, while every side effect — HTTP calls, emails, database writes — lives in an activity so it can be retried and recorded exactly once.

Defining a workflow

[Workflow("greeting")]
public sealed class GreetingWorkflow
{
    [WorkflowRun]
    public async ValueTask<string> RunAsync(
        IWorkflowContext ctx,
        string name,
        CancellationToken cancellationToken
    )
    {
        // ...
    }
}

Defining activities

public sealed class EmailActivities
{
    [Activity("send-welcome")]
    public string SendWelcome(string email)
    {
        // side effects go here
    }
}

Calling activities from a workflow

var receipt = await ctx.Activity(
    (PaymentActivities a) => a.Charge(input.UserName, input.Amount),
    cancellationToken
);

Registration

builder.Services.AddPgWorkflows(pg =>
    pg.UsePostgres(connectionString)
        .AddWorkflow<GreetingWorkflow>()
        .AddActivities<EmailActivities>()
);