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Bilal Atique
4e3ec7cc27
Closes #4300. The TypeScript `BlobFile` only had `size()`, `read()` and `readRange()`, while the Rust `BlobFile` behind it also has `seek`, `tell`, `read_up_to`, `read_ranges` and `close`. This exposes those on the Node binding: - `read(maxBytes?)` reads at most `maxBytes` from the cursor (Rust `read_up_to`). Without the argument it reads to the end, as before. - `readRanges([{ start, end }, ...])` reads several half-open ranges and returns one buffer per range, in order. Like `readRange`, it does not move the cursor. - `seek(position)` and `tell()` move and report the cursor. - `close()` releases the handle, and `isClosed()` reports it. Every read, `seek` and `tell` after `close()` fails with "blob file is already closed". A second `close()` does nothing. The binding keeps its own `closed` flag, the same way the Python `BlobFile` does. Offsets and lengths are `bigint`, like `readRange` and `size()`. `BlobRange` is exported as a type. The new tests in `table.test.ts` cover chunked reads with `read(maxBytes)`, `seek` and `tell`, a negative seek position, `readRanges` order and cursor, a `readRanges` end past the blob size, and reads after `close()`. The Node docs under `docs/src/js` are regenerated with `pnpm run docs`. I left the `ReadableStream`/async iterator idea from the issue out of this PR. The AbortSignal work in #4288 touches the same methods, so it can follow on top of this.
LanceDB JavaScript SDK
A JavaScript library for LanceDB.
Installation
npm install @lancedb/lancedb
This will download the appropriate native library for your platform. We currently support:
- Linux (x86_64 and aarch64 on glibc and musl)
- MacOS (Intel and ARM/M1/M2)
- Windows (x86_64 and aarch64)
Usage
Basic Example
import * as lancedb from "@lancedb/lancedb";
const db = await lancedb.connect("data/sample-lancedb");
const table = await db.createTable("my_table", [
{ id: 1, vector: [0.1, 1.0], item: "foo", price: 10.0 },
{ id: 2, vector: [3.9, 0.5], item: "bar", price: 20.0 },
]);
const results = await table.vectorSearch([0.1, 0.3]).limit(20).toArray();
console.log(results);
The quickstart contains more complete examples.
Development
See CONTRIBUTING.md for information on how to contribute to LanceDB.