BackWave.Testing 1.1.1

BackWave.Testing

Deterministic tests for your real jobs: the In-Memory Store plus Virtual Time behind one harness. Enqueue real jobs, advance the clock, and assert through the same Monitor API the dashboard uses. Every due instant — mints, retries, Lease expiries, Continuations — is processed synchronously and in order. A year of cron behavior tests in milliseconds and never flakes in CI.

The full pattern: define, enqueue, advance, assert

// 1. Define the job — the same record and handler your app ships.
[Job("send-invoice")]
public sealed record SendInvoice(string OrderId);

public sealed class SendInvoiceHandler(IInvoiceGateway gateway) : IJobHandler<SendInvoice>
{
    public Task HandleAsync(SendInvoice job, JobContext context, CancellationToken cancellationToken)
        => gateway.SendAsync(job.OrderId, cancellationToken);
}

[Fact]
public async Task InvoiceGoesOut_TwoDaysAfterTheOrder()
{
    // 2. Build the harness from your registry and DI services.
    var services = new ServiceCollection()
        .AddSingleton<IInvoiceGateway, FakeInvoiceGateway>()
        .AddTransient<IJobHandler<SendInvoice>, SendInvoiceHandler>()
        .BuildServiceProvider();
    var harness = new BackWaveHarness(BackWaveJobs.CreateRegistry(), services);

    // 3. Enqueue and advance Virtual Time — "advance 3 days" runs everything due in between.
    var jobId = await harness.EnqueueAsync(new SendInvoice("order-42"), delay: TimeSpan.FromDays(2));
    await harness.AdvanceAsync(TimeSpan.FromDays(3));

    // 4. Assert through the Monitor API — the same surface production observability uses.
    var job = await harness.Monitor.GetJobAsync(jobId);
    Assert.Equal(JobState.Succeeded, job!.State);
}

What the harness covers

• Retries: a failing Attempt reschedules at its backoff instant; AdvanceAsync stops there and runs it. Assert job.Attempt afterwards.
• Recurring Schedules: UpsertRecurringAsync("nightly", Cron.Daily(3), template) then AdvanceAsync(TimeSpan.FromDays(365)) mints and runs a year of ticks in milliseconds.
• Continuations: EnqueueContinuationAsync(receipt, parentId) releases when the parent goes terminal during an advance.
• Transactional Enqueue: harness.BeginTransaction() honors the rollback-means-it-never- existed guarantee, so outbox-replacement code paths are testable:

using (var transaction = harness.BeginTransaction())
{
    await harness.EnqueueAsync(new SendInvoice("order-43"), transaction: transaction);
    transaction.Rollback(); // the job never existed — not claimable, not visible
}

• Job Manifest: commit JobManifest.Verify(registry, "jobs.manifest") in a test and a removed or renamed Wire Name fails in PR review instead of quarantining in production.

Determinism rules

Virtual Time starts at a fixed instant (configurable via BackWaveHarnessOptions.StartTime) and only moves when you advance it. No wall clock, no sleeps, no polling — the same test input always produces the same execution order.