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Bilal Atique
0a1c1a04c7
Closes #4288. Blob reads in Node can now be cancelled. `BlobFile.read`, `readRange` and `readRanges`, and `Table.fetchBlobs` and `fetchBlobFiles` take an optional `{ signal?: AbortSignal }` (new `BlobReadOptions` type). When the signal aborts, the call rejects with `signal.reason` (an `AbortError` unless the caller gave a reason) and the native future is dropped, so the read stops instead of running to completion. A signal that is already aborted rejects before any read starts. How it works: - On the Rust side, these five methods are now sync `#[napi]` methods that return `env.spawn_future(...)`. The future is wrapped in `futures::future::abortable`, and the abort handle is registered with napi's `AbortSignal::on_abort`. napi's `AbortSignal` is `Rc`-based, so it can't be an argument of an `async fn`, which is why the methods changed shape. The TypeScript signatures are unchanged apart from the new optional argument. - napi-rs installs its own `onabort` on the signal it receives, which would overwrite a handler the caller set. So the TypeScript wrapper passes a private `AbortController` signal to the native call for each request, forwards the caller's abort to it with `addEventListener(..., { once: true })`, and removes the listener when the call settles. Tests in `table.test.ts`: - an already aborted signal rejects on all five methods, and the handle still reads afterwards - a custom abort reason is what the call rejects with - a read with a signal that never aborts returns normally and leaves no `abort` listener on the signal - aborting a 32 MiB `readRange` right after it starts rejects with `AbortError`, and the same handle reads again afterwards The Node docs under `docs/src/js` are regenerated. I didn't add a test for where the `read()` cursor ends up after a mid-flight abort on a local table. The remote `BlobFile` documents that a cancelled read leaves the cursor unchanged, but I haven't confirmed the same for the native Lance handle, so the docs don't claim it.