API Reference
Index
The main entry point for creating and querying search indexes.
Static Methods
Index.create(schema?, walSyncPolicy?, commitPolicy?)
Create a new in-memory (ephemeral) index.
- Parameters:
schema(Schema, optional) – Schema definition.walSyncPolicy(WalSyncPolicy, optional) – WAL durability policy. Omit to keep the default per-record sync. See WAL sync policy / durability.commitPolicy(CommitPolicy, optional) – Auto-commit policy. Omit to keep the default (manual; caller-driven commits). See Commit policy / auto-commit.
- Returns:
Promise<Index>
Index.open(name, schema?, walSyncPolicy?, commitPolicy?)
Open or create a persistent index backed by OPFS.
- Parameters:
name(string) – Index name (OPFS subdirectory).schema(Schema, optional) – Schema definition.walSyncPolicy(WalSyncPolicy, optional) – WAL durability policy. Omit to keep the default per-record sync. See WAL sync policy / durability.commitPolicy(CommitPolicy, optional) – Auto-commit policy. Omit to keep the default (manual; caller-driven commits). See Commit policy / auto-commit.
- Returns:
Promise<Index>
Instance Methods
putDocument(id, document)
Replace a document (upsert).
- Parameters:
id(string) – Document identifier.document(object) – Key-value pairs matching schema fields.
- Returns:
Promise<void>
addDocument(id, document)
Append a document version (multi-version RAG pattern).
- Parameters / Returns: Same as
putDocument.
putDocuments(docs)
Batched upsert. Applies the pairs in order with one WAL fsync for the whole batch; duplicate ids within one batch dedup (last occurrence wins). Fails fast at the first bad entry, and the applied prefix is not rolled back (retrying is idempotent).
- Parameters:
docs(Array<[string, object]>) – An array of[id, document]pairs.
- Returns:
Promise<void>
addDocuments(docs)
Batched chunk append. Like putDocuments but repeated ids accumulate as separate versions.
- Parameters / Returns: Same as
putDocuments.
getDocuments(id)
Retrieve all versions of a document.
- Parameters:
id(string)
- Returns:
Promise<object[]>
deleteDocuments(id)
Delete all versions of a document.
- Parameters:
id(string)
- Returns:
Promise<void>
commit()
Flush writes and make changes searchable. If opened with
Index.open(), data is also persisted to OPFS.
- Returns:
Promise<void>
flushWal()
Force a durable WAL barrier on the in-memory engine WAL. See
WAL sync policy / durability for the wasm
caveats — notably, this does not persist to OPFS; call commit() for
durable persistence.
- Returns:
Promise<void>
search(query, limit?, offset?)
Search using a DSL string query.
- Parameters:
query(string) – Query DSL (e.g."title:hello").limit(number, default 10)offset(number, default 0)
- Returns:
Promise<SearchResult[]>
searchTerm(field, term, limit?, offset?)
Search for an exact term.
- Parameters:
field(string) – Field name.term(string) – Exact term.limit,offset(number, optional)
- Returns:
Promise<SearchResult[]>
searchVector(field, vector, limit?, offset?)
Search by vector similarity.
- Parameters:
field(string) – Vector field name.vector(number[]) – Query embedding.limit,offset(number, optional)
- Returns:
Promise<SearchResult[]>
searchVectorText(field, text, limit?, offset?)
Search by text (embedded by the registered embedder).
- Parameters:
field(string) – Vector field name.text(string) – Text to embed.limit,offset(number, optional)
- Returns:
Promise<SearchResult[]>
searchGeo3dDistance(field, x, y, z, distanceM, limit?, offset?)
Sphere search over a 3D ECEF point field. Returns documents whose (x, y, z)
coordinate is within distanceM metres of the centre. See
Geo3d concepts for ECEF theory.
- Parameters:
field(string) – Geo3d field name.x,y,z(number) – Centre ECEF coordinate (metres).distanceM(number) – Maximum distance from the centre (metres).limit,offset(number, optional)
- Returns:
Promise<SearchResult[]>
searchGeo3dBoundingBox(field, minX, minY, minZ, maxX, maxY, maxZ, limit?, offset?)
Axis-aligned 3D bounding-box search over a 3D ECEF point field.
- Parameters:
field(string) – Geo3d field name.minX,minY,minZ,maxX,maxY,maxZ(number) – Box bounds (metres).limit,offset(number, optional)
- Returns:
Promise<SearchResult[]>
searchGeo3dNearest(field, x, y, z, k, limit?, offset?, initialRadiusM?, maxRadiusM?)
k-nearest-neighbour search over a 3D ECEF point field. Returns the k
documents closest to (x, y, z). The optional initialRadiusM and
maxRadiusM parameters tune the iterative-expansion search cone.
- Parameters:
field(string) – Geo3d field name.x,y,z(number) – Centre ECEF coordinate (metres).k(number) – Number of nearest neighbours to return.limit,offset(number, optional)initialRadiusM,maxRadiusM(number, optional)
- Returns:
Promise<SearchResult[]>
stats()
Return index statistics.
- Returns:
{ documentCount: number, vectorFields: { [name]: { count, dimension } } }
WAL sync policy / durability
Each write is appended to the engine’s in-memory write-ahead log (WAL).
Index.create and Index.open accept an optional walSyncPolicy that
controls how often that WAL is flushed. The default (omit the argument) is
per-record sync.
class WalSyncPolicy {
static perRecord(): WalSyncPolicy;
static group(
maxRecords?: number,
maxBytes?: number,
maxIntervalMs?: number,
): WalSyncPolicy;
}
| Constructor | Description |
|---|---|
WalSyncPolicy.perRecord() | Default. Flush after every WAL record. |
WalSyncPolicy.group(...) | Group commit. Batch the flush across writes. |
group(...) parameters (omit any argument to keep its default):
| Parameter | Default | Description |
|---|---|---|
maxRecords | 1024 | Flush once this many records have accumulated. |
maxBytes | 1048576 (1 MiB) | Flush once this many unsynced bytes have accumulated. |
maxIntervalMs | none | Periodic flush timer (milliseconds). No-op on wasm (see caveats). |
With group commit the engine WAL is flushed when either maxRecords or
maxBytes is reached, and always at commit(). A crash can lose up to the
last unsynced batch — the same trade-off as SQLite’s synchronous = NORMAL.
flushWal() (durable barrier)
flushWal() forces a flush of the in-memory engine WAL on demand.
- Returns:
Promise<void>
WASM caveats
WebAssembly has no background threads or direct filesystem, so two behaviours differ from the native bindings:
maxIntervalMsis a no-op. The periodic flush timer requires a background thread, which is unavailable on wasm. Group commit still flushes on themaxRecords/maxBytesthresholds and atcommit().flushWal()flushes the in-memory engine WAL only. OPFS persistence still happens atcommit(). For durable persistence on wasm, callcommit().
import { Index, Schema, WalSyncPolicy } from "./pkg/laurus_wasm.js";
const schema = new Schema();
schema.addTextField("title");
// Opt into group commit. maxIntervalMs is accepted but ignored on wasm.
const policy = WalSyncPolicy.group(4096, undefined, 1000);
const index = await Index.open("my-index", schema, policy);
for (let i = 0; i < 10000; i++) {
await index.putDocument(`doc${i}`, { title: `Document ${i}` });
}
await index.flushWal(); // flushes the engine WAL (not OPFS)
await index.commit(); // makes changes searchable AND persists to OPFS
Commit policy / auto-commit
A commit materializes buffered writes into the searchable stores.
Index.create and Index.open accept an optional commitPolicy that controls
whether the engine commits on your behalf. The default (omit the argument) is
manual: you drive every commit() yourself.
class CommitPolicy {
static manual(): CommitPolicy;
static everyDocs(n: number): CommitPolicy;
static intervalMs(ms: number): CommitPolicy;
}
| Constructor | Description |
|---|---|
CommitPolicy.manual() | Default. No auto-commit; the caller drives every commit(). |
CommitPolicy.everyDocs(n) | Auto-commit after every n applied documents. |
CommitPolicy.intervalMs(ms) | Auto-commit at least every ms milliseconds via a background timer (default: none). Native only — no-op on wasm. |
With everyDocs(n) the engine commits once every n applied documents. The
counter spans both singular and batch ingest, and it also fires within a
batch — a putDocuments call larger than n triggers one or more commits mid
batch. everyDocs(0) is valid and disables auto-commit, which is equivalent to
CommitPolicy.manual().
intervalMs(ms) is the time-based counterpart of everyDocs: a background
timer commits at least every ms milliseconds, so a trailing partial batch is
committed even while ingestion is idle. It is native only — see the WASM
note below.
commitPolicy is orthogonal to walSyncPolicy: walSyncPolicy governs how
often the WAL is fsynced for durability, while commitPolicy governs when the
stores materialize buffered writes into searchable state. They are configured
independently.
WASM note
Unlike walSyncPolicy’s maxIntervalMs background timer (a no-op on wasm),
everyDocs needs no background thread — the document counter is checked
inline during ingestion — so auto-commit works fully under WebAssembly.
intervalMs, by contrast, relies on a background timer just like
walSyncPolicy’s maxIntervalMs, and wasm has no background threads. The
factory still constructs a value so portable policy code keeps compiling, but
the timer never runs under WebAssembly and intervalMs has no effect on
wasm — no timed commit ever fires. Use everyDocs for auto-commit on wasm.
import { Index, Schema, CommitPolicy } from "./pkg/laurus_wasm.js";
const schema = new Schema();
schema.addTextField("title");
// Auto-commit after every 1000 applied documents.
const index = await Index.open(
"my-index",
schema,
undefined,
CommitPolicy.everyDocs(1000),
);
for (let i = 0; i < 10000; i++) {
await index.putDocument(`doc${i}`, { title: `Document ${i}` });
}
// The engine has auto-committed 10 times; no explicit commit() required.
Schema
Builder for defining index fields and embedders.
Constructor
new Schema()
Create an empty schema.
Methods
addTextField(name, stored?, indexed?, termVectors?, analyzer?)
Add a full-text field. analyzer is the name of a parameter-less
built-in ("standard", "english", "keyword", "simple", "noop")
or the name of a runtime analyzer registered via addAnalyzer().
For Japanese morphological analysis, build a JapaneseAnalyzer from
raw IPADIC bytes and register it with addAnalyzer() first; see
JapaneseAnalyzer.fromBytes
and addAnalyzer below.
addIntegerField(name, stored?, indexed?, multiValued?)
Add a 64-bit integer field. Pass multiValued: true to accept arrays of
integers; range queries then match if any value satisfies the predicate
(Lucene-style “any match” with constant scoring).
addFloatField(name, stored?, indexed?, multiValued?)
Add a 64-bit float field. Pass multiValued: true to accept arrays of
floats; range queries then match if any value satisfies the predicate
(Lucene-style “any match” with constant scoring).
addBooleanField(name, stored?, indexed?)
Add a boolean field.
addDatetimeField(name, stored?, indexed?)
Add a date/time field.
addGeoField(name, stored?, indexed?)
Add a geographic coordinate field.
addGeo3dField(name, stored?, indexed?)
Add a 3D ECEF Cartesian point field. Values are submitted as a { x, y, z }
object with metres units. See Geo3d concepts for
ECEF theory.
The WASM binding does not expose Geo3dDistanceQuery / Geo3dBoundingBoxQuery
/ Geo3dNearestQuery as JS classes (wasm-bindgen cannot expose dyn Query
trait objects). Instead, use the Index.searchGeo3dDistance /
Index.searchGeo3dBoundingBox / Index.searchGeo3dNearest methods documented
above.
addBytesField(name, stored?)
Add a binary data field.
addHnswField(name, dimension, distance?, m?, efConstruction?, defaultEfSearch?, embedder?, quantizer?, subvectorCount?, rerankStorage?, pqCodebookPath?)
Add an HNSW vector index field.
distance:"cosine"(default),"euclidean","dot_product","manhattan","angular"m: Branching factor (default 16)efConstruction: Build-time expansion (default 200)defaultEfSearch: Schema-level default for the query-timeef_searchcandidate-list size; omit to use the internal fallback of 50quantizer:"scalar_8bit"(default) or"product_quantization"(requiressubvectorCount)subvectorCount: number of PQ sub-vectors; must dividedimensionrerankStorage: omit (default) or"f32"to store a full-precision rerank sidecarpqCodebookPath: omit (default) or the storage-relative file name of a shared PQ codebook (Issue #631) to reuse across segments instead of per-segment training
addFlatField(name, dimension, distance?, embedder?)
Add a brute-force vector index field.
addIvfField(name, dimension, distance?, nClusters?, nProbe?, embedder?)
Add an IVF vector index field.
nClusters: Number of partitioning clusters (default 100)nProbe: Number of clusters to probe at query time (default 1)
Vector quantization & rerank storage (HNSW fields):
quantizer—"scalar_8bit"(default, 4× compression) or"product_quantization"for higher compression. Product quantization requiressubvectorCount(must dividedimension).rerankStorage— set to"f32"to write a full-precision*.hnsw.f32sidecar enabling exact Stage-2 rerank; omit to keep the int8-only segment.pqCodebookPath— storage-relative file name of a shared PQ codebook (Issue #631), trained once via thelaurus train pq-codebookCLI command. Only meaningful withquantizer: "product_quantization"; commits then encode against the pre-trained codebook instead of re-training k-means per segment. Omit to keep per-segment training.
addAnalyzer(name, analyzer)
Register a pre-built analyzer instance under name. Resolved before the
parameter-less built-in names and before schema.analyzers definitions
when text fields reference an analyzer by name.
Currently only JapaneseAnalyzer instances built via
JapaneseAnalyzer.fromBytes
are accepted here. The runtime registry is the only practical way to use
the Japanese analyzer in browser WASM, where the
{ "language": "japanese", "dict": ... } preset cannot resolve a
filesystem path.
import { JapaneseAnalyzer, Schema } from "laurus-wasm";
import { downloadDictionary, loadDictionaryFiles } from "laurus-wasm/opfs";
await downloadDictionary("./dict/lindera-ipadic.zip", "ipadic");
const f = await loadDictionaryFiles("ipadic");
const ja = JapaneseAnalyzer.fromBytes(
f.metadata, f.dictDa, f.dictVals, f.dictWordsIdx,
f.dictWords, f.matrixMtx, f.charDef, f.unk, "normal",
);
const schema = new Schema();
schema.addAnalyzer("ja-ipadic", ja);
schema.addTextField("body", undefined, undefined, undefined, "ja-ipadic");
addEmbedder(name, config)
Register a named embedder. WASM supports two type values:
"precomputed"— No embedding is performed; vectors are passed directly viaputDocument()/searchVector()."callback"— Provide a JavaScript callbackembed: (text) => Promise<number[]>that the engine will invoke during ingestion andsearchVectorText(). This enables in-engine auto-embedding using Transformers.js or any other in-browser embedding library.
// Precomputed embedder
schema.addEmbedder("precomputed-embedder", { type: "precomputed" });
// Callback embedder (e.g. backed by Transformers.js)
schema.addEmbedder("callback-embedder", {
type: "callback",
embed: async (text) => {
const output = await pipeline(text, { pooling: "mean", normalize: true });
return Array.from(output.data);
},
});
setDefaultFields(fields)
Set the default search fields.
setDynamicFieldPolicy(policy)
Set how the engine treats fields that appear in ingested documents but are
absent from the schema. policy is one of "strict", "dynamic"
(default), or "ignore" (case-insensitive). Throws on an invalid value.
"strict"— Reject the document."dynamic"— Infer a type for each undeclared field and add it to the schema. Warning: integer fields silently truncate incoming float values (3.14→3)."ignore"— Silently drop the undeclared fields.
See Schema & Fields for the full behaviour matrix.
dynamicFieldPolicy()
Returns the current policy as a lowercase string.
fieldNames()
Returns an array of defined field names.
toString()
Returns a string representation of the schema ("Schema(fields=[...])").
SearchResult
interface SearchResult {
id: string;
score: number;
document: object | null;
}
Analysis
JapaneseAnalyzer
Japanese morphological analyzer constructed from raw Lindera dictionary
bytes. Browser WASM has no real filesystem, so the standard
{ "language": "japanese", "dict": "/path/to/ipadic" } preset cannot
be used. Instead, fetch a Lindera dictionary archive (typically
lindera-ipadic-X.Y.Z.zip), store it in OPFS via the
OPFS helpers, and pass the eight component byte
arrays to JapaneseAnalyzer.fromBytes.
JapaneseAnalyzer.fromBytes(metadata, dictDa, ..., mode?)
Static factory that builds an analyzer from raw IPADIC bytes.
Arguments (all Uint8Array except mode):
| Argument | Source file |
|---|---|
metadata | metadata.json |
dictDa | dict.da (Double-Array Trie) |
dictVals | dict.vals |
dictWordsIdx | dict.wordsidx |
dictWords | dict.words |
matrixMtx | matrix.mtx |
charDef | char_def.bin |
unk | unk.bin |
mode | "normal" (default) or "decompose" |
Throws if any component fails to deserialize or the mode string is invalid.
import { JapaneseAnalyzer } from "laurus-wasm";
import { loadDictionaryFiles } from "laurus-wasm/opfs";
const f = await loadDictionaryFiles("ipadic");
const ja = JapaneseAnalyzer.fromBytes(
f.metadata, f.dictDa, f.dictVals, f.dictWordsIdx,
f.dictWords, f.matrixMtx, f.charDef, f.unk,
"normal",
);
The pipeline is NFKC normalization → Japanese iteration mark normalization → Lindera morphological tokenization → lowercase → Japanese stop word filter — identical to the japanese preset on the
native side.
OPFS Helpers
The laurus-wasm/opfs subpath bundles helpers for downloading,
storing, and loading Lindera dictionaries from the browser’s Origin
Private File System. Used together with JapaneseAnalyzer.fromBytes.
import {
downloadDictionary,
getDictionaryVersion,
loadDictionaryFiles,
hasDictionary,
listDictionaries,
removeDictionary,
} from "laurus-wasm/opfs";
| Function | Description |
|---|---|
downloadDictionary(url, name, options?) | Fetch a .zip, decompress with the Web DecompressionStream API, and store the eight Lindera files under laurus/dictionaries/<name>/ in OPFS. options.onProgress({ phase, loaded?, total? }) reports progress. options.version stores a version stamp next to the files (see below). |
getDictionaryVersion(name) | Return the version stamp stored by downloadDictionary, or null if the dictionary or its stamp does not exist. |
loadDictionaryFiles(name) | Read the eight files back as a { metadata, dictDa, dictVals, dictWordsIdx, dictWords, matrixMtx, charDef, unk } object suitable for JapaneseAnalyzer.fromBytes. |
hasDictionary(name) | true if the dictionary directory exists in OPFS. |
listDictionaries() | Return an array of stored dictionary names. |
removeDictionary(name) | Delete the dictionary directory. |
The binary dictionary format is tied to the Lindera (and daachorse)
version compiled into the WASM binary, so a dictionary cached in OPFS
becomes unreadable after your app updates its Lindera version
(deserialization fails with an InvalidAutomatonError). Pass the
Lindera version your zip was built for as options.version when
downloading, then compare getDictionaryVersion(name) against the
version your current build expects on startup and re-download on
mismatch. A null stamp should be treated as a mismatch.
Browser CORS prevents fetching directly from GitHub Releases, so host
the zip on the same origin as your app (the Laurus demo bundles
./dict/lindera-ipadic.zip alongside the WASM at deploy time).
WhitespaceTokenizer
const tokenizer = new WhitespaceTokenizer();
const tokens = tokenizer.tokenize("hello world");
// [{ text: "hello", position: 0, ... }, { text: "world", position: 1, ... }]
SynonymDictionary
const dict = new SynonymDictionary();
dict.addSynonymGroup(["ml", "machine learning"]);
SynonymGraphFilter
new SynonymGraphFilter(dictionary, keepOriginal = true, boost = 1.0)
dictionary(SynonymDictionary) — Source synonym groups.keepOriginal(boolean, defaulttrue) — Keep the original token alongside the inserted synonyms.boost(number, default1.0) — Score boost applied to inserted synonym tokens.
const filter = new SynonymGraphFilter(dict, true, 0.8);
const expanded = filter.apply(tokens);