NexJob.MongoDB 5.7.0

NexJob.MongoDB

MongoDB storage provider for NexJob — the background job scheduler for .NET 8+.

Backed by the official MongoDB.Driver, this provider uses FindOneAndUpdateAsync with atomic condition filters for concurrency-safe, lock-free job claiming across distributed workers.

Installation

dotnet add package NexJob.MongoDB

Quick Start

Register MongoDB storage in your dependency injection container before calling AddNexJob():

using NexJob;
using NexJob.MongoDB;

var builder = WebApplication.CreateBuilder(args);

// 1. Register MongoDB storage
builder.Services.AddNexJobMongoDB(
    connectionString: builder.Configuration.GetConnectionString("MongoConnection")!,
    databaseName: "nexjob");

// 2. Register NexJob core services
builder.Services.AddNexJob(options =>
{
    options.Workers = 10;
    options.Queues = ["default", "critical"];
});

Or provide a pre-configured IMongoDatabase:

var client = new MongoClient("mongodb://localhost:27017");
var database = client.GetDatabase("nexjob");

builder.Services.AddNexJobMongoDB(database);

High-Throughput Batch Processing

For heavy ingestion workloads, enable batch processing to group job reservations and vectorized acknowledgments using UpdateManyAsync:

builder.Services.AddNexJobMongoDB(
    connectionString: builder.Configuration.GetConnectionString("MongoConnection")!,
    databaseName: "nexjob");

builder.Services.AddNexJob(options =>
{
    // Workers dynamically batch fetches to keep all idle slots busy
    options.Workers = 30;
    options.PollingInterval = TimeSpan.FromMilliseconds(20);

    // Commit successful jobs in asynchronous batches via UpdateManyAsync ($in: [ids])
    options.EnableBatchAcknowledgment = true;
});

Features

• High-Throughput Batching: Atomic batch claim and vectorized batch acknowledgment (UpdateManyAsync by ID set).
• Atomic State Transitions: Uses MongoDB FindOneAndUpdate with optimistic filter criteria (status: Enqueued) to prevent race conditions across multiple nodes without global locks.
• Automatic Index Creation: Automatically builds compound and unique indexes on initialization for queues, priority, idempotency keys, and scheduled timestamps.
• Document-Oriented Storage: Flexible document schema for job arguments, execution metadata, and logs.
• Distributed Recurring Locks: Manages cron recurring job execution safely across replica sets using atomic collection locks (nexjob_recurring_locks).
• Runtime Settings Store: Persists dynamic queue limits and pause status in MongoDB.
• Scoped Date Serialization: DateTimeOffset is stored as a UTC ISO 8601 string for NexJob documents only; NexJob no longer registers a global serializer that would change how your own types are stored. If your application relied on the old global registration, pass keepLegacyGlobalDateTimeOffsetSerializer: true to AddNexJobMongoDB for one release.

Collections

The provider automatically manages the following collections in the target database:

Connection String Example

{
  "ConnectionStrings": {
    "MongoConnection": "mongodb://user:secret@localhost:27017/?authSource=admin&replicaSet=rs0"
  }
}