## Problem
When `batchTrigger()` is called with large payloads, each item's payload
is uploaded to R2 server-side during the streaming loop before being
enqueued. This makes the loop slow — around 3 seconds per item. Workers
pick up and execute each item as it's enqueued, running concurrently
with the ongoing stream.
For the last item in the batch, a race exists between the streaming loop
finishing and the batch completion cleanup:
1. The loop enqueues the last item and returns from `enqueueBatchItem()`
2. A waiting worker picks up the item almost instantly and executes it
3. `recordSuccess()` fires, `processedCount` hits the expected total,
`finalizeBatch()` runs
4. `cleanup()` deletes all Redis keys for the batch, including
`enqueuedItemsKey`
5. The streaming loop exits and calls `getBatchEnqueuedCount()` — reads
the now-deleted key — returns 0
The count check finds `enqueuedCount (0) !== batch.runCount`, falls
through to a Postgres fallback, but the fallback only checked `sealed`.
The BatchQueue completion path sets `status = COMPLETED` in Postgres
without setting `sealed = true` (that's the streaming endpoint's job),
so the fallback misses it too.
This causes the endpoint to return `sealed: false`. The SDK treats this
as retryable and retries up to 5 times with exponential backoff. Each
retry calls `enqueueBatchItem()`, which reads the batch meta key from
Redis — also deleted by `cleanup()` — and throws "Batch not found or not
initialized" (500). The final retry gets a 422 because the batch is
already COMPLETED, which the SDK does not retry, causing an `ApiError`
to be thrown from `await batchTrigger()` in the parent run — even though
all child runs completed successfully.
## Fix
In the Postgres fallback inside `StreamBatchItemsService`, also check
`status === "COMPLETED"` alongside `sealed`. This covers the
fast-completion path where the BatchQueue finishes all runs before the
streaming endpoint gets to seal the batch normally.
Also switches `findUnique` to `findFirst` per webapp convention.
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Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Matt Aitken
fc71e7dd75