Files
lancedb/nodejs/lancedb/index.ts
T
Dan Rammer f1c4967eeb feat: bring the MemWAL LSM surface to parity across the SDKs (#3962)
## Why

Four of the eight LSM methods are **remote-only in the core**. `impl
BaseTable for NativeTable` implements only
`set`/`unset`/`get_lsm_write_spec` and `close_lsm_writers`; `flush_lsm`,
`compact_lsm` and `get_lsm_stats` fall through to trait defaults
returning `NotSupported` (`rust/lancedb/src/table.rs:679,687,696`), and
`checkpoint_lsm` is built on all three.

That explains the state of the bindings: Node had bound the four that
work against a local table and stopped, so a Cloud user could install an
LSM write spec but had no way to observe fresh-tier state or drive a
checkpoint. Java had none of it at all.

| SDK | set/unset/get spec | closeWriters | flush | compact | getStats |
checkpoint |
|---|---|---|---|---|---|---|
| Rust core |  |  |  |  |  |  |
| Python |  |  |  |  |  |  |
| Node *(before)* |  |  | — | — | — | — |
| **Node (after)** |  |  | **new** | **new** | **new** | **new** |
| Java *(before)* | — | — | — | — | — | — |
| **Java (after)** | **new** | n/a | **new** | **new** | **new** |
**new** |

Go and C are separate repos and are out of scope here. `closeLsmWriters`
drains cached in-process shard writers, so it has no meaning for Java,
which is a pure REST client.

## Node

Adds napi bindings for `flushLsm`, `compactLsm`, `checkpointLsm` and
`getLsmStats`, plus typed `LsmStats` / `BucketStats` / `GenerationStats`
/ `MemtableStats` objects — typed rather than a JSON blob, matching the
existing `LsmWriteSpec` object in the same file, with `u64` cast to
`i64` per that file's convention.

Because these four are remote-only, the new tests assert each binding
reaches the core and surfaces `NotSupported` against a local table. That
covers the wiring; behavior against a real endpoint stays covered by the
mocked-endpoint tests in `rust/lancedb/src/remote/table.rs`.

## Python

No new methods. All eight are on `LanceTable`, `AsyncTable` and
`RemoteTable` — the last four landed on the sync `RemoteTable` in #3961,
which is merged into this branch.

What was missing here was reachability. `LsmWriteSpec` was importable
only from the private `lancedb._lancedb`, appearing in `table.py` solely
under `if TYPE_CHECKING:`, and `docs/src/python/python.md` had no
mention of it, which per the repo's docs guidance means it rendered
nowhere in the API reference. It is now `lancedb.LsmWriteSpec`, in
`__all__`, and documented.

## Java

Java reaches LanceDB purely over REST through the generated Lance
Namespace client, and these routes are not in that spec, so they are
issued through a small dedicated client rather than added to the spec.
That call is revisitable — LSM is one of four unspecified route families
alongside `multipart_write`, `page_cache/prewarm` and
`branches/diff|merge`. If those are ever regularized into the spec as a
group, `LanceDbTableLsm` is one file that gets deleted.

`LsmWriteSpec` here is deliberately **not**
`org.lance.memwal.InitializeMemWalParams`. That type defaults to
maintaining *no* indexes where a spec here defaults to maintaining
*every* index, and it cannot express the `null` that asks the server to
resolve the set:

| Value | On the wire | Meaning |
|---|---|---|
| unset (null) | `null` | Server resolves **every** maintainable index |
| `Collections.emptyList()` | `[]` | Maintain **none** |
| `Arrays.asList("id_idx")` | `["id_idx"]` | Exactly those |

A dedicated test pins null and `[]` as distinct on the wire, since
collapsing them is the failure mode that motivated a LanceDB-owned type.

`checkpointLsm` is ported from `rust/lancedb/src/table/checkpoint.rs`
with its constants and status semantics intact: 429/503 retried in place
against an 8-budget, 421 restarting from flush against a 3-budget, 5s
poll, and a target watermark fixed after the seal so it terminates under
write load.

`getLsmStats` returns typed `LsmStats` / `BucketStats` /
`GenerationStats` / `MemtableStats`, mirroring the Rust structs in
`rust/lancedb/src/table/lsm_stats.rs` and the objects Node exposes.
Decoding is strict — see below.

## Review feedback

Both gatekeeper findings were real. Each was reproduced against the
scripted test server first, and each fix ships with the reproducer as a
regression test.

**The transport was doubling every checkpoint retry budget.**
`HttpClients.createDefault()` installs Apache's default response retry
strategy, whose retryable-status list is exactly 429 and 503 — the two
statuses `isRetryable` owns. A 429 held against `flush_lsm` issued
**18** wire requests where the loop intends 9, and `compact_lsm` was
retried in place despite the loop being built to fall through to a fresh
stats poll instead. Timing confirmed the mechanism: that run took 25.4s
≈ 16.3s of the loop's own backoff plus 9 × the transport's 1s retry
interval.

Automatic retries are now disabled, so the checkpoint loop is the sole
owner of the 421/429/503 transitions. A side effect worth noting:
`testCheckpointRetriesRetryableStatusInPlace` was passing on a
transport-absorbed 429 and never reaching `issue()`'s retry branch at
all. It now exercises the real path.

**Stats decoding failed open.** `getLsmStats` read the response with
Jackson's `path()`, which yields a missing node that iterates as an
empty array — making "malformed" indistinguishable from "no buckets",
which is indistinguishable from "drained". Four separate payloads made
`checkpointLsm()` report convergence for a checkpoint that never ran:

| Response | Before | Now |
|---|---|---|
| `{"lsm_stats": null}` or absent key | disabled ✓ | disabled ✓ |
| `{"lsm_stats": {}}` | **reported success** | `IllegalStateException` |
| empty response body | **reported success** | `IllegalStateException` |
| bucket missing required fields | **reported success** |
`IllegalStateException` |

The empty-body row is the one to weight: a proxy 200 with no body is a
realistic production event, and it silently reported a checkpoint that
never happened.

Decoding is now strict and fails closed, matching the serde contract on
the Rust side exactly. One deliberate deviation from the review comment,
which asked that *only* explicit JSON `null` count as disabled: Rust has
`#[serde(default)]` on `lsm_stats`, so an **absent key** decodes to
`None` there too. Java now matches that. It is an absent-or-malformed
**`buckets`** that fails closed, which is the case the comment was
actually protecting.

## Testing

- Java: **33 passing** (8 existing + 25 LSM) against a scripted
`com.sun.net.httpserver.HttpServer` — no new test dependency. Wire
assertions mirror `rust/lancedb/src/remote/table.rs:6581-6748`;
checkpoint tests cover convergence, not piling onto a latched bucket,
421 restart-from-flush, 429 retry-in-place, terminal-status propagation,
reissue exhaustion, the exact wire-request count against the retry
budget, and five malformed stats payloads.
- Node: **19 LSM tests passing**; `cargo check`, `npm run build`, `npm
run tsc`, `npm run lint`, `npm run docs` all clean.
- Python: `ruff format --check` and `ruff check` clean.
- Java formatting: `./mvnw -pl lancedb-core spotless:apply` and
`spotless:check` both clean under a JDK 11 toolchain.

## Note: spotless needs a pre-16 JDK

`./mvnw spotless:apply` fails on JDK 16+ with
`JCTree$JCImport.getQualifiedIdentifier()` — google-java-format 1.7,
pinned at `java/pom.xml:34`, predates JDK 16's compiler API change.
**This is pre-existing** and reproduces on a pristine `main` checkout.

It is not a blocker, just a toolchain requirement. Spotless was run
against these sources under JDK 11 and both `spotless:apply` and
`spotless:check` pass on the whole module:

```shell
JAVA_HOME=/path/to/jdk11 ./mvnw -pl lancedb-core spotless:apply
```

Bumping the plugin so it works on modern JDKs is still worth doing, but
separately from this PR.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-19 11:44:46 -05:00

615 lines
16 KiB
TypeScript

// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright The LanceDB Authors
import {
Connection,
LocalConnection,
cleanseStorageOptions,
} from "./connection";
import {
ConnectNamespaceOptions,
ConnectionOptions,
Connection as LanceDbConnection,
JsHeaderProvider as NativeJsHeaderProvider,
Session,
tokenize as nativeTokenize,
} from "./native.js";
import { HeaderProvider } from "./header";
import type { BaseTokenizer } from "./indices";
import type { FtsToken } from "./table";
// Re-export native header provider for use with connectWithHeaderProvider
export { JsHeaderProvider as NativeJsHeaderProvider } from "./native.js";
// OpenTelemetry metrics bridge. Only the high-level entry point is public; the
// underlying recorder/catalog/snapshot functions remain internal plumbing that
// `otel.ts` consumes from the native module.
export { instrumentLanceDbMetrics } from "./otel";
export {
AddColumnsSql,
ConnectionOptions,
ConnectNamespaceOptions,
IndexStatistics,
IndexConfig,
ClientConfig,
TimeoutConfig,
RetryConfig,
TlsConfig,
OptimizeStats,
CompactionStats,
RemovalStats,
TableStatistics,
FragmentStatistics,
FragmentSummaryStats,
Tags,
TagContents,
BranchContents,
MergeResult,
AddResult,
AddColumnsResult,
RefreshColumnResult,
AlterColumnsResult,
UpdateFieldMetadataResult,
DeleteResult,
DropColumnsResult,
UpdateResult,
SplitCalculatedOptions,
SplitRandomOptions,
SplitHashOptions,
SplitSequentialOptions,
ShuffleOptions,
OAuthConfig as NativeOAuthConfig,
} from "./native.js";
export {
makeArrowTable,
MakeArrowTableOptions,
Data,
VectorColumnOptions,
} from "./arrow";
export {
Connection,
CreateTableOptions,
TableNamesOptions,
OpenTableOptions,
ListNamespacesOptions,
CreateNamespaceOptions,
DropNamespaceOptions,
ListNamespacesResponse,
CreateNamespaceResponse,
DropNamespaceResponse,
DescribeNamespaceResponse,
RenameTableOptions,
} from "./connection";
export {
Job,
JobDescription,
JobFailureInfo,
JobInfo,
Session,
} from "./native.js";
export {
ExecutableQuery,
Query,
QueryBase,
VectorQuery,
TakeQuery,
AnalyzePlanDistributedMetrics,
QueryExecutionOptions,
ColumnOrdering,
FullTextSearchOptions,
RecordBatchIterator,
FullTextQuery,
MatchQuery,
PhraseQuery,
BoostQuery,
MultiMatchQuery,
BooleanQuery,
FullTextQueryType,
Operator,
Occur,
} from "./query";
export {
Index,
IndexOptions,
IvfPqOptions,
IvfRqOptions,
IvfFlatOptions,
HnswPqOptions,
HnswSqOptions,
FtsOptions,
BaseTokenizer,
} from "./indices";
export {
Table,
Branches,
BranchColumnSummary,
BranchColumnChange,
BranchIndexSummary,
BranchRowCountSummary,
MergeBlocker,
BranchDiff,
MergePreview,
MergeBranchResult,
AddDataOptions,
UpdateOptions,
OptimizeOptions,
Version,
WriteProgress,
FtsToken,
TokenizeTableOptions,
LsmWriteSpec,
LsmStats,
BucketStats,
GenerationStats,
MemtableStats,
ColumnAlteration,
FieldMetadataUpdate,
} from "./table";
export {
HeaderProvider,
StaticHeaderProvider,
OAuthHeaderProvider,
TokenResponse,
} from "./header";
export { OAuthConfig, OAuthFlowType } from "./oauth";
export { MergeInsertBuilder, WriteExecutionOptions } from "./merge";
export * as embedding from "./embedding";
export { permutationBuilder, PermutationBuilder } from "./permutation";
export { Scannable, ScannableOptions } from "./scannable";
export * as rerankers from "./rerankers";
export {
SchemaLike,
TableLike,
FieldLike,
RecordBatchLike,
DataLike,
IntoVector,
MultiVector,
} from "./arrow";
export { IntoSql, packBits } from "./util";
/**
* Options for tokenizing a full-text search query without a table index.
*/
export interface TokenizeOptions {
/**
* The tokenizer to use. The default is "simple".
*/
baseTokenizer?: BaseTokenizer;
/** Language for stemming and stop words. */
language?: string;
/** Maximum token length; tokens longer than this are ignored. */
maxTokenLength?: number;
/** Whether to lowercase tokens. */
lowercase?: boolean;
/** Whether to stem tokens. */
stem?: boolean;
/** Whether to remove stop words. */
removeStopWords?: boolean;
/**
* Custom stop words that replace the built-in list for `language`.
*
* This option only affects tokenization when `removeStopWords` is true.
*
* `undefined` keeps the built-in language list. An empty array explicitly
* replaces it with no stop words.
*/
customStopWords?: string[];
/** Whether to fold ASCII characters. */
asciiFolding?: boolean;
/** N-gram minimum length. */
ngramMinLength?: number;
/** N-gram maximum length. */
ngramMaxLength?: number;
/** Whether to only emit token prefixes for the n-gram tokenizer. */
prefixOnly?: boolean;
}
/**
* Tokenize a full-text search query using an explicit tokenizer.
*
* This does not require a table or FTS index. The tokenizer options match
* {@link Index.fts}.
*/
export async function tokenize(
query: string,
options?: Partial<TokenizeOptions>,
): Promise<FtsToken[]> {
return await nativeTokenize(
query,
options?.baseTokenizer,
options?.language,
options?.maxTokenLength,
options?.lowercase,
options?.stem,
options?.removeStopWords,
options?.customStopWords,
options?.asciiFolding,
options?.ngramMinLength,
options?.ngramMaxLength,
options?.prefixOnly,
);
}
/**
* Connect to a LanceDB instance at the given URI.
*
* Accepted formats:
*
* - `/path/to/database` - local database
* - `s3://bucket/path/to/database` or `gs://bucket/path/to/database` - database on cloud storage
* - `db://host:port` - remote database (LanceDB cloud)
* @param {string} uri - The uri of the database. If the database uri starts
* with `db://` then it connects to a remote database.
* @see {@link ConnectionOptions} for more details on the URI format.
* @param options - The options to use when connecting to the database
* @example
* ```ts
* const conn = await connect("/path/to/database");
* ```
* @example
* ```ts
* const conn = await connect(
* "s3://bucket/path/to/database",
* {storageOptions: {timeout: "60s"}
* });
* ```
* @example
* Using with a header provider for per-request authentication:
* ```ts
* const provider = new StaticHeaderProvider({
* "X-API-Key": "my-key"
* });
* const conn = await connectWithHeaderProvider(
* "db://host:port",
* options,
* provider
* );
* ```
*/
export async function connect(
uri: string,
options?: Partial<ConnectionOptions>,
session?: Session,
headerProvider?:
| HeaderProvider
| (() => Record<string, string>)
| (() => Promise<Record<string, string>>),
): Promise<Connection>;
/**
* Connect to a LanceDB instance at the given URI.
*
* Accepted formats:
*
* - `/path/to/database` - local database
* - `s3://bucket/path/to/database` or `gs://bucket/path/to/database` - database on cloud storage
* - `db://host:port` - remote database (LanceDB cloud)
* @param options - The options to use when connecting to the database
* @see {@link ConnectionOptions} for more details on the URI format.
* @example
* ```ts
* const conn = await connect({
* uri: "/path/to/database",
* storageOptions: {timeout: "60s"}
* });
* ```
*
* @example
* ```ts
* const session = Session.default();
* const conn = await connect({
* uri: "/path/to/database",
* session: session
* });
* ```
*/
export async function connect(
options: Partial<ConnectionOptions> & { uri: string },
): Promise<Connection>;
export async function connect(
uriOrOptions: string | (Partial<ConnectionOptions> & { uri: string }),
optionsOrSession?: Partial<ConnectionOptions> | Session,
sessionOrHeaderProvider?:
| Session
| HeaderProvider
| (() => Record<string, string>)
| (() => Promise<Record<string, string>>),
headerProvider?:
| HeaderProvider
| (() => Record<string, string>)
| (() => Promise<Record<string, string>>),
): Promise<Connection> {
let uri: string | undefined;
let finalOptions: Partial<ConnectionOptions> = {};
let finalHeaderProvider:
| HeaderProvider
| (() => Record<string, string>)
| (() => Promise<Record<string, string>>)
| undefined;
if (typeof uriOrOptions !== "string") {
// First overload: connect(options)
const { uri: uri_, ...opts } = uriOrOptions;
uri = uri_;
finalOptions = opts;
} else {
// Second overload: connect(uri, options?, session?, headerProvider?)
uri = uriOrOptions;
// Handle optionsOrSession parameter
if (optionsOrSession && "inner" in optionsOrSession) {
// Second param is session, so no options provided
finalOptions = {};
} else {
// Second param is options
finalOptions = (optionsOrSession as Partial<ConnectionOptions>) || {};
}
// Handle sessionOrHeaderProvider parameter
if (
sessionOrHeaderProvider &&
(typeof sessionOrHeaderProvider === "function" ||
"getHeaders" in sessionOrHeaderProvider)
) {
// Third param is header provider
finalHeaderProvider = sessionOrHeaderProvider as
| HeaderProvider
| (() => Record<string, string>)
| (() => Promise<Record<string, string>>);
} else {
// Third param is session, header provider is fourth param
finalHeaderProvider = headerProvider;
}
}
if (!uri) {
throw new Error("uri is required");
}
finalOptions = (finalOptions as ConnectionOptions) ?? {};
(<ConnectionOptions>finalOptions).storageOptions = cleanseStorageOptions(
(<ConnectionOptions>finalOptions).storageOptions,
);
// Create native header provider if one was provided
let nativeProvider: NativeJsHeaderProvider | undefined;
if (finalHeaderProvider) {
if (typeof finalHeaderProvider === "function") {
nativeProvider = new NativeJsHeaderProvider(async () =>
finalHeaderProvider(),
);
} else if (
finalHeaderProvider &&
typeof finalHeaderProvider.getHeaders === "function"
) {
nativeProvider = new NativeJsHeaderProvider(async () =>
finalHeaderProvider.getHeaders(),
);
}
}
const nativeConn = await LanceDbConnection.new(
uri,
finalOptions,
nativeProvider,
);
return new LocalConnection(nativeConn);
}
/**
* Configuration for the built-in directory namespace (`"dir"`).
*
* The directory namespace stores tables under a single root path (local
* filesystem or object storage URI). See
* {@link https://docs.lancedb.com/namespaces} for the documented surface;
* less-common knobs live under {@link DirNamespaceConfig.extraProperties}.
*/
export interface DirNamespaceConfig {
/** Root path or URI containing the LanceDB tables. */
root: string;
/**
* Whether to maintain a namespace manifest at the root. Required for
* child namespaces. Defaults to true on the impl side.
*/
manifestEnabled?: boolean;
/**
* Additional raw properties passed verbatim to the namespace
* implementation (e.g. `storage.*`, `credential_vendor.*`). Typed
* fields above take precedence on key collision.
*/
extraProperties?: Record<string, string>;
}
/**
* Configuration for the built-in REST namespace (`"rest"`).
*
* The REST namespace talks to a remote catalog server over HTTP. See
* {@link https://docs.lancedb.com/namespaces} for the documented surface;
* less-common knobs (TLS, metrics) live under
* {@link RestNamespaceConfig.extraProperties}.
*/
export interface RestNamespaceConfig {
/** Catalog endpoint URL. */
uri: string;
/**
* HTTP headers forwarded with each request. Keys are passed through
* as-is (e.g. `"x-api-key"`, `"Authorization"`).
*/
headers?: Record<string, string>;
/**
* Additional raw properties passed verbatim to the namespace
* implementation (e.g. `tls.*`, `ops_metrics_enabled`, `delimiter`).
* Typed fields above take precedence on key collision.
*/
extraProperties?: Record<string, string>;
}
function dirConfigToProperties(
config: DirNamespaceConfig,
): Record<string, string> {
// Spread the whole input so that unknown keys (e.g. a raw `manifest_enabled`
// passed via the dynamic-impl path) flow through instead of being dropped.
// Typed transformations layer on top.
const { manifestEnabled, extraProperties, ...rest } = config;
const properties: Record<string, string> = {
...(extraProperties ?? {}),
...(rest as Record<string, string>),
};
if (manifestEnabled !== undefined) {
properties.manifest_enabled = String(manifestEnabled);
}
return properties;
}
function restConfigToProperties(
config: RestNamespaceConfig,
): Record<string, string> {
const { headers, extraProperties, ...rest } = config;
const properties: Record<string, string> = {
...(extraProperties ?? {}),
...(rest as Record<string, string>),
};
if (headers) {
for (const [name, value] of Object.entries(headers)) {
properties[`headers.${name}`] = value;
}
}
return properties;
}
/**
* Connect to a LanceDB database through a namespace.
*
* Unlike {@link connect}, which routes by URI scheme (local path vs.
* `db://` cloud), `connectNamespace` always returns a namespace-backed
* connection. The `implName` selects the namespace implementation:
*
* - `"dir"` — directory namespace, configured with {@link DirNamespaceConfig}.
* - `"rest"` — remote REST catalog, configured with {@link RestNamespaceConfig}.
* - Any other string — full module path for a custom implementation,
* configured with a free-form string-keyed `properties` map.
*
* @example Typed dir namespace
* ```ts
* const db = await connectNamespace("dir", { root: "/path/to/db" });
* await db.createTable("users", [{ id: 1 }]);
* ```
*
* @example Typed REST namespace with auth headers
* ```ts
* const db = await connectNamespace("rest", {
* uri: "https://catalog.example.com",
* headers: { "x-api-key": process.env.CATALOG_KEY ?? "" },
* });
* ```
*
* @example Custom implementation with raw properties
* ```ts
* const db = await connectNamespace("my.custom.Namespace", {
* endpoint: "...",
* });
* ```
*/
export function connectNamespace(
implName: "dir",
config: DirNamespaceConfig,
options?: Partial<ConnectNamespaceOptions>,
): Promise<Connection>;
/**
* Connect through the built-in REST namespace.
*
* Configured with {@link RestNamespaceConfig}. See the function-level
* documentation above for the full surface, examples, and how this
* relates to {@link connect}.
*
* @example
* ```ts
* const db = await connectNamespace("rest", {
* uri: "https://catalog.example.com",
* headers: { "x-api-key": process.env.CATALOG_KEY ?? "" },
* });
* ```
*/
export function connectNamespace(
implName: "rest",
config: RestNamespaceConfig,
options?: Partial<ConnectNamespaceOptions>,
): Promise<Connection>;
/**
* Connect through a custom namespace implementation by full module path,
* configured with a free-form string-keyed `properties` map. Use the
* typed overloads above for the built-in `"dir"` and `"rest"` impls.
*
* See the function-level documentation above for examples and how this
* relates to {@link connect}.
*
* @example
* ```ts
* const db = await connectNamespace("my.custom.Namespace", {
* endpoint: "...",
* });
* ```
*/
export function connectNamespace(
implName: string,
properties: Record<string, string>,
options?: Partial<ConnectNamespaceOptions>,
): Promise<Connection>;
export async function connectNamespace(
implName: string,
configOrProperties:
| DirNamespaceConfig
| RestNamespaceConfig
| Record<string, string>,
options?: Partial<ConnectNamespaceOptions>,
): Promise<Connection> {
let properties: Record<string, string>;
if (implName === "dir") {
properties = dirConfigToProperties(
configOrProperties as DirNamespaceConfig,
);
} else if (implName === "rest") {
properties = restConfigToProperties(
configOrProperties as RestNamespaceConfig,
);
} else {
properties = configOrProperties as Record<string, string>;
}
const finalOptions: ConnectNamespaceOptions = (options ??
{}) as ConnectNamespaceOptions;
finalOptions.storageOptions = cleanseStorageOptions(
finalOptions.storageOptions,
);
const nativeConn = await LanceDbConnection.newWithNamespace(
implName,
properties,
finalOptions,
);
return new LocalConnection(nativeConn);
}