Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsFor an image batch API, give each image its own queue job when callers need per-image progress, failure details, and retries. Store batch status in application data, use BullMQ job progress for work-in-progress updates, and use QueueEvents when another process needs live events. Retry only the failed images that are safe to run again.
The examples below use BullMQ. Check the documentation for your installed BullMQ major version before copying API calls: the Job API reference linked here is versioned v1, and the current API surface may differ.
Choose the failure boundary: one job per image or one job per batch
Decide what should fail and retry together before designing the API. BullMQ documents several ways to model batches, including independent jobs, flows, a single job that processes many items, and BullMQ Pro worker batches. These are not interchangeable designs; see BullMQ’s batch patterns.
| Design | Failure and retry scope | Progress granularity | Best fit |
|---|---|---|---|
| Independent job per image | One image can fail and be retried without retrying successful images. | Per-image job state; the API aggregates batch totals. | Separate reporting, retries, or completion outcomes for each image. |
| One job processes the batch | The batch shares a job’s retry, timeout, and completion outcome. | The job can publish aggregate progress, such as completed images out of total. | All images should be treated as one unit of work. |
| BullMQ Pro worker batch | Uses Pro-specific batch and wrapper-job semantics. | Depends on the Pro batch API and events. | Use only when you intend to adopt and handle those distinct semantics. |
For most APIs that must show which images succeeded and retry only the failures, independent jobs provide the clearest boundary. Flows can model dependencies between jobs, but do not choose them merely to represent a flat list of unrelated images.
Recommended Free Tools
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
Submit a batch and return stable identifiers
A practical REST shape is POST /batches to accept image references and return a stable batch ID plus each image’s job ID. This is an application design, not a BullMQ-mandated contract. Use a durable batch record to connect those identifiers to caller-visible status.
// Illustrative Express/BullMQ shape; adapt to your installed BullMQ version.
app.post('/batches', async (req, res, next) => {
try {
const batchId = createStableBatchId();
const imageIds = validateImageIds(req.body.imageIds);
await batchStore.create({ batchId, imageIds, status: 'queued' });
const jobs = await imageQueue.addBulk(
imageIds.map((imageId) => ({
name: 'process-image',
data: { batchId, imageId },
opts: { attempts: 3, backoff: { type: 'exponential', delay: 1000 } },
})),
);
await batchStore.recordJobs(batchId, jobs.map((job, index) => ({
imageId: imageIds[index],
jobId: job.id,
status: 'queued',
})));
res.status(202).json({ batchId, jobs: jobs.map((job, index) => ({ imageId: imageIds[index], jobId: job.id })) });
} catch (error) {
next(error);
}
});The attempt and backoff values above illustrate explicit configuration; choose them for your image processor and its dependencies rather than treating them as universal defaults. Keep the input references and output destinations stable enough that a retry can safely repeat the operation.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
Track progress for a BullMQ job
For a single job that processes many images, call job.updateProgress as each item finishes. BullMQ supports numeric progress and object progress; an object makes batch counters explicit. See the BullMQ job progress guide and the versioned v1 Job API reference.
const imageQueue = new Queue('images', { connection });
const worker = new Worker('images', async (job) => {
const { imageIds } = job.data;
for (let index = 0; index < imageIds.length; index += 1) {
await processImage(imageIds[index]);
await job.updateProgress({ completed: index + 1, total: imageIds.length });
}
return { processed: imageIds.length };
}, { connection });Do not use one job’s progress object as if it were per-image retry state: it describes that job’s work. With one job per image, track each item’s state separately and calculate batch totals from the item records or job states.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Expose progress through a batch-status endpoint
Provide a read endpoint such as GET /batches/{id} that reads durable status and returns an aggregate plus item-level details. The precise response format is yours to define; a useful shape is:
{
"batchId": "batch_123",
"status": "processing",
"counts": { "total": 3, "completed": 1, "failed": 1, "active": 1 },
"items": [
{ "imageId": "img_a", "jobId": "job_a", "status": "completed", "attemptsMade": 1 },
{ "imageId": "img_b", "jobId": "job_b", "status": "failed", "attemptsMade": 3, "error": { "code": "PROCESSING_FAILED", "message": "Image processing failed" } },
{ "imageId": "img_c", "jobId": "job_c", "status": "active", "progress": { "stage": "resize" }, "attemptsMade": 1 }
]
}Sanitize failure information before returning it. Expose actionable codes and safe messages, not stack traces, credentials, internal paths, or raw downstream responses. Make the batch’s overall status rule explicit—for example, whether a batch is “completed” only when all items finish, or “partially_failed” when at least one item ultimately fails.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Choose polling or live updates
Polling
For a simple API, clients can periodically call the batch-status endpoint. This keeps the status contract independent of a long-lived connection and lets clients recover after disconnecting. Use a sensible polling interval and avoid querying Redis or recalculating an entire batch more often than your service can support.
Server-Sent Events or WebSockets
For live dashboards, a service can listen for cross-worker job lifecycle and progress events with BullMQ QueueEvents, then relay updates over Server-Sent Events or WebSockets. QueueEvents is designed to observe events from workers across processes. It uses Redis Streams, which the guide describes as resilient to disconnections compared with ordinary pub/sub.
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
const queueEvents = new QueueEvents('images', { connection });
queueEvents.on('progress', ({ jobId, data }) => {
// Resolve jobId to batchId, then publish a sanitized update to connected clients.
publishProgress(jobId, data);
});
queueEvents.on('completed', ({ jobId, returnvalue }) => {
publishCompleted(jobId, returnvalue);
});
queueEvents.on('failed', ({ jobId, failedReason }) => {
publishFailed(jobId, sanitizeFailure(failedReason));
});
// During application shutdown:
await queueEvents.close();Close QueueEvents during shutdown to release its Redis connection. The events guide says the stream is automatically trimmed by default to approximately 10,000 events; configuration can change this. Treat that as bounded event history, not as a permanent audit log or the sole source for a later API read.
Retry failed image jobs deliberately
BullMQ automatic retries require attempts greater than one. If you configure attempts without a backoff option, failed jobs are retried immediately. A fixed backoff waits a set interval; exponential backoff increases the delay with each retry and supports jitter to vary it. You can also define a custom worker backoff strategy. Consult the BullMQ retry guide for the exact options supported by your installed version.
The guide’s example using three total attempts and a 1,000 ms exponential seed produces retry delays of one, two, and four seconds. That is an example, not a general policy: choose the delay and attempt count based on the failure class and the downstream service’s limits. Do not retry permanent failures such as invalid image input without first correcting the underlying data.
BullMQ’s retry guide states: “The exceptions thrown in a processor must be an Error object for BullMQ to work correctly.” Throw actual JavaScript Error instances so queue failure handling works as intended.
const worker = new Worker('images', async (job) => {
try {
return await processImage(job.data.imageId);
} catch (cause) {
throw new Error('Image processing failed', { cause });
}
}, {
connection,
settings: {
// Configure a custom backoff strategy here only if the built-in policies
// do not fit your retry rules; verify the installed version's API.
},
});For manual recovery, first identify eligible failed jobs and then retry those jobs rather than replaying the whole batch. The versioned Job API reference includes a manual retry method, but verify its availability and behavior for your BullMQ version and job state.
Quick Recap
Keep status durable and retries safe
- Persist batch and per-image status somewhere the API can query reliably; queue events are useful for updates but their stream is trimmed.
- Record attempt counts, final state, output reference, and a sanitized failure code/message for each image.
- Make output writes and side effects safe to repeat. BullMQ does not prescribe a universal idempotency scheme, so use application-level protections such as deterministic output keys or duplicate detection appropriate to your system.
- Retry only items whose failure is transient or otherwise eligible under your policy; retain the original batch ID while recording that a new attempt was requested.
- Test interrupted workers, duplicate events, client reconnects, partial batch success, exhausted attempts, and retry requests against the BullMQ major version you deploy.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
