Batch example

A batch can begin as correlation rather than orchestration. Add a nullable identifier to your concrete job record, construct several records, and store them with the same value.

This example extends the complete EF Core provider, but the same record field and queue helper work with any provider.

Extend the job record

Replace the baseline JobRecord with this version, then create a migration for BatchId.

JobRecord.cs

public sealed class JobRecord : IJobStorageRecord
{
    // Required by IJobStorageRecord
    public Guid TrackingId { get; set; }
    public DateTime CreatedOn { get; set; }
    public DateTime? ExecuteAfter { get; set; }
    public DateTime? ExpireOn { get; set; }
    public bool IsComplete { get; set; }
    public string JobType { get; set; } = null!;
    public string MethodName { get; set; } = null!;
    public string ArgumentsJson { get; set; } = null!;

    // Added for batch correlation
    public Guid? BatchId { get; set; }
}

Add the batch helper

Add this new static extension class to your application. It creates ordinary GUSTO records and assigns the same BatchId to each one.

BatchQueueExtensions.cs

using System.Linq.Expressions;
using ByteBard.GUSTO;

public static class BatchQueueExtensions
{
    public static async Task<Guid> EnqueueBatchAsync(
        this JobQueue<JobRecord> queue,
        IEnumerable<Expression<Func<Task>>> calls,
        CancellationToken cancellationToken = default)
    {
        var batchId = Guid.NewGuid();

        foreach (var call in calls)
        {
            var record = queue.ConstructRecordFromExpression(
                call,
                executeAfter: null);

            record.BatchId = batchId;
            await queue.StorageProvider.StoreJobAsync(
                record,
                cancellationToken);
        }

        return batchId;
    }
}

Call the new helper with the jobs that belong to the batch:

var batchId = await queue.EnqueueBatchAsync([
    () => onboarding.CreateDirectoryEntryAsync(customerId),
    () => billing.ProvisionPlanAsync(customerId),
    () => messaging.SendWelcomeAsync(customerId)
]);

The worker still sees independent jobs. BatchId lets your application query progress, attach logs, or find all records in a workflow.

A batch can also be used as the parent of a continuation. The continuation remains waiting until every job with the matching BatchId has completed successfully. This is optional behavior built on top of batching; see the batch continuation example.

Partial batch creation

The helper stores one record at a time. A failure can therefore leave a partial batch. If “all records exist or none do” matters, move batch insertion into a provider-specific transaction or add a bulk operation outside the GUSTO interface.

Execution order and concurrency

Jobs with the same batch ID may run concurrently, sequentially, or on different workers depending on claiming, ordering, and configured concurrency. A batch ID is correlation metadata; it is not a scheduling primitive by itself.

If downstream work must wait for all members, model that as an explicit continuation with a transactional release condition.