9 Commits
0.1.4 ... 0.2.4

Author SHA1 Message Date
bfb3f0efd3 Fixed post install step
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2026-08-24 11:12:03 -04:00
4ef022aa0e Fixed post install step
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2026-08-24 11:10:57 -04:00
fb7ae55d49 Fixed post install step
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2026-08-24 11:09:50 -04:00
bc90557de7 use kiwix-serach as prefilter before fuzzy ranking instead of building index
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2026-08-24 11:02:47 -04:00
96ddcbe67a Garbage colleciton fix
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2026-08-22 17:57:19 -04:00
d10ee1d686 Auto caching
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2026-08-22 17:31:50 -04:00
ffdca81c78 Decompression caching and preview links
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2026-08-22 16:52:07 -04:00
aedb117002 Create search index cache and return more meta
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2026-08-22 14:24:22 -04:00
4278ea9df9 Added delete
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2026-08-22 13:01:19 -04:00
9 changed files with 405 additions and 109 deletions

10
.gitignore vendored Normal file
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@@ -0,0 +1,10 @@
.idea
.vscode
logs
*.log
bin/*.dll
bin/kiwix*
node_modles
zims

87
bin/install-kwix.js Normal file
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@@ -0,0 +1,87 @@
import fs from 'node:fs';
import os from 'node:os';
import path from 'node:path';
import https from 'node:https';
import {execFileSync} from 'node:child_process';
import {fileURLToPath} from 'node:url';
const __dirname = path.dirname(fileURLToPath(import.meta.url));
const VERSION = '3.8.1';
const BASE_URL = 'https://download.kiwix.org/release/kiwix-tools';
const PLATFORM_MAP = {linux: 'linux', darwin: 'macos', win32: 'win'};
const BIN_NAME = process.platform === 'win32' ? 'kiwix-search.exe' : 'kiwix-search';
const BIN_DIR = path.join(__dirname, '..', 'bin'); // project root/bin
const BIN_PATH = path.join(BIN_DIR, BIN_NAME);
/** Download a file, following redirects. */
function download(url, dest) {
return new Promise((resolve, reject) => {
const file = fs.createWriteStream(dest);
https.get(url, res => {
if (res.statusCode >= 300 && res.statusCode < 400 && res.headers.location) {
file.close();
return resolve(download(res.headers.location, dest));
}
if (!res.statusCode || res.statusCode >= 400) {
return reject(new Error(`Download failed: ${res.statusCode} ${res.statusMessage}`));
}
res.pipe(file);
file.on('finish', () => file.close(resolve));
}).on('error', err => fs.unlink(dest, () => reject(err)));
});
}
/** Recursively search a directory for a file by name. */
function findFile(dir, name) {
for (const entry of fs.readdirSync(dir, {withFileTypes: true})) {
const full = path.join(dir, entry.name);
if (entry.isDirectory()) {
const found = findFile(full, name);
if (found) return found;
} else if (entry.name === name) {
return full;
}
}
return null;
}
async function downloadAndExtract() {
const platformName = PLATFORM_MAP[process.platform];
if (!platformName) throw new Error(`Unsupported platform: ${process.platform}`);
const ext = platformName === 'win' ? 'zip' : 'tar.gz';
const archiveName = `kiwix-tools_${platformName}-x86_64-${VERSION}.${ext}`;
const url = `${BASE_URL}/${archiveName}`;
const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'kiwix-tools-'));
const archivePath = path.join(tmpDir, archiveName);
console.log('Downloading kiwix-tools from:', url);
await download(url, archivePath);
console.log('Extracting...');
execFileSync('tar', ['-xf', archivePath, '-C', tmpDir]); // bsdtar handles zip too
const extractedBin = findFile(tmpDir, BIN_NAME);
if (!extractedBin) throw new Error(`Could not find ${BIN_NAME} in extracted archive`);
const extractedDir = path.dirname(extractedBin);
await fs.promises.mkdir(BIN_DIR, {recursive: true});
// Copy the binary plus any DLLs sitting alongside it (Windows deps)
for (const entry of await fs.promises.readdir(extractedDir)) {
if (entry === BIN_NAME || entry.toLowerCase().endsWith('.dll')) {
await fs.promises.copyFile(path.join(extractedDir, entry), path.join(BIN_DIR, entry));
}
}
if (process.platform !== 'win32') await fs.promises.chmod(BIN_PATH, 0o755);
await fs.promises.rm(tmpDir, {recursive: true, force: true});
console.log('Installed to:', BIN_PATH);
}
downloadAndExtract().catch(err => {
console.error(err);
process.exit(1)
}).finally(() => process.exit());

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@@ -1,6 +1,6 @@
{
"name": "@ztimson/zim-utils",
"version": "0.1.4",
"version": "0.2.4",
"description": "Native, dependency-light ZIM archive reader/searcher and Kiwix catalog downloader for Node.js",
"author": "Zak Timson",
"license": "MIT",
@@ -11,6 +11,9 @@
"url": "https://git.zakscode.com/ztimson/zim-utils"
},
"main": "src/index.js",
"scripts": {
"postinstall": "node ./bin/install-kwix.js"
},
"dependencies": {
"@ztimson/utils": "^0.30.7",
"lzma1": "^0.3.0",

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@@ -1,40 +1,44 @@
import {fuzzyMatch} from './utils.js';
import {decodeHtml} from '@ztimson/utils';
export const CATALOG_URL = 'https://library.kiwix.org/catalog/v2/entries';
export const CATALOG_URL = 'https://library.kiwix.org';
const PAGE_SIZE = 100;
/** Parses `<entry>` blocks out of a Kiwix catalog OPDS XML response. */
function parseEntries(xml) {
function parseEntries(xml, catalog = CATALOG_URL) {
const blocks = xml.match(/<entry>[\s\S]*?<\/entry>/g) || [];
return blocks.map(b => {
const grab = re => (b.match(re) || [])[1] || '';
const linkMatch = b.match(/<link[^>]*type=["']application\/x-zim[^"']*["'][^>]*href=["']([^"']+)["']/);
const iconMatch = b.match(/<link[^>]*rel=["']http:\/\/opds-spec\.org\/image\/thumbnail["'][^>]*href=["']([^"']+)["']/)
|| b.match(/<link[^>]*type=["']image\/[^"']*["'][^>]*href=["']([^"']+)["']/);
let tags = grab(/<tags>([^<]*)<\/tags>/);
if(tags) tags = tags.split(';');
const name = grab(/<name>([^<]*)<\/name>/);
return {
id: grab(/<id>([^<]*)<\/id>/),
title: decodeHtml(grab(/<title>([^<]*)<\/title>/)),
updated: new Date(grab(/<updated>([^<]*)<\/updated>/)),
summary: decodeHtml(grab(/<summary>([^<]*)<\/summary>/)),
language: grab(/<language>([^<]*)<\/language>/),
name: grab(/<name>([^<]*)<\/name>/),
name,
category: grab(/<category>([^<]*)<\/category>/),
tags,
mediaCount: Number(grab(/<mediaCount>([^<]*)<\/mediaCount>/)) || 0,
author: grab(/<author>\s*<name>([^<]*)<\/name>\s*<\/author>/m),
publisher: grab(/<publisher>\s*<name>([^<]*)<\/name>\s*<\/publisher>/m),
articleCount: Number(grab(/<articleCount>([^<]*)<\/articleCount>/)) || 0,
sizeMb: linkMatch ? (Number((b.match(/length=["'](\d+)["']/) || [])[1] || 0) / 1024 / 1024).toFixed(1) : '?',
href: linkMatch ? linkMatch[1] : null,
sizeMb: linkMatch ? +(Number((b.match(/length=["'](\d+)["']/) || [])[1] || 0) / 1024 / 1024).toFixed(1) : '?',
download: linkMatch ? linkMatch[1] : null,
icon: iconMatch ? new URL(iconMatch[1], catalog).href : null,
viewer: name ? new URL(`viewer#${name}`, catalog).href : null,
};
});
}
async function fetchEntries(term, lang, url = CATALOG_URL) {
const params = new URLSearchParams({q: term, count: String(PAGE_SIZE), lang: lang || 'eng'});
const res = await fetch(`${url}?${params}`);
const res = await fetch(`${url}/catalog/v2/entries?${params}`);
if (!res.ok) throw new Error(`${res.status} ${res.statusText}`);
return parseEntries(await res.text());
}
@@ -42,7 +46,7 @@ async function fetchEntries(term, lang, url = CATALOG_URL) {
/** Looks up a single catalog entry by exact `name` (used to check for available updates). */
export async function zimCatalogInfo(name, url = CATALOG_URL) {
const params = new URLSearchParams({name, count: '5'});
const res = await fetch(`${url}?${params}`);
const res = await fetch(`${url}/catalog/v2/entries?${params}`);
if (!res.ok) return null;
return parseEntries(await res.text()).find(e => e.name === name) || null;
}

32
src/decompress-worker.js Normal file
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@@ -0,0 +1,32 @@
'use strict';
import {parentPort} from 'node:worker_threads';
import {decompress as lzmaDecompress} from 'lzma1';
import {ZstdCodec} from 'zstd-codec';
let zstdStreamingPromise = null;
function getZstd() {
if (!zstdStreamingPromise) {
zstdStreamingPromise = new Promise(resolve => ZstdCodec.run(zstd => resolve(new zstd.Streaming())));
}
return zstdStreamingPromise;
}
/** Rebuilds a full 13-byte "alone" LZMA header from libzim's truncated 5-byte one (unknown size). */
function toLzmaAloneStream(body) {
const header = Buffer.concat([body.subarray(0, 5), Buffer.alloc(8, 0xff)]);
return Buffer.concat([header, body.subarray(5)]);
}
parentPort.on('message', async ({id, compType, body}) => {
try {
const buf = Buffer.from(body);
const data = compType === 4
? Buffer.from(lzmaDecompress(toLzmaAloneStream(buf)))
: Buffer.from((await getZstd()).decompress(new Uint8Array(buf)));
parentPort.postMessage({id, data}, [data.buffer]);
} catch (e) {
parentPort.postMessage({id, error: e.message});
}
});

50
src/decompress.js Normal file
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@@ -0,0 +1,50 @@
'use strict';
import {Worker} from 'node:worker_threads';
import path from 'node:path';
import os from 'node:os';
import {fileURLToPath} from 'node:url';
const __dirname = path.dirname(fileURLToPath(import.meta.url));
/** Round-robin pool of worker threads for off-main-thread cluster decompression. */
class DecompressPool {
#workers = [];
#next = 0;
#pending = new Map(); // id -> {resolve, reject}
#nextId = 0;
#active = 0;
constructor(size = Math.max(1, os.cpus().length - 1)) {
for (let i = 0; i < size; i++) this.#spawn();
}
#spawn() {
const worker = new Worker(path.join(__dirname, 'decompress-worker.js'));
worker.on('message', ({id, data, error}) => {
const task = this.#pending.get(id);
if (!task) return;
this.#pending.delete(id);
// No work left in flight -> safe to let the process exit again.
if (--this.#active === 0) for (const w of this.#workers) w.unref();
error ? task.reject(new Error(error)) : task.resolve(Buffer.from(data));
});
worker.unref(); // idle workers must never keep a short script/server alive
this.#workers.push(worker);
}
/** Decompresses `{compType, body}` on the next worker in rotation. `body` must be a Uint8Array/Buffer view. */
run({compType, body}) {
const worker = this.#workers[this.#next];
this.#next = (this.#next + 1) % this.#workers.length;
const id = this.#nextId++;
const owned = new Uint8Array(body);
if (this.#active++ === 0) for (const w of this.#workers) w.ref();
return new Promise((resolve, reject) => {
this.#pending.set(id, {resolve, reject});
worker.postMessage({id, compType, body: owned}, [owned.buffer]);
});
}
}
export const decompressPool = new DecompressPool();

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@@ -4,16 +4,24 @@ import {pipeline} from 'node:stream/promises';
import {Readable} from 'node:stream';
import {ZimReader} from './reader.js';
import {zimCatalog, zimCatalogInfo, CATALOG_URL} from './catalog.js';
import {fuzzyMatch, titleFromUrl} from './utils.js';
const DEFAULT_READER_TTL = 60_000;
/** Manages a local directory of ZIM archives: listing, update checks, downloads, and reading. */
export class ZimManager {
#catalog;
#dir;
#readerTTL;
#clusterTTL;
#readers = new Map(); // file -> {reader, timer}
#opening = new Map(); // file -> Promise<ZimReader>, dedupes concurrent first-open races
constructor(dir, catalog = CATALOG_URL) {
/** @param {{catalog?: string, readerTTL?: number, clusterTTL?: number}} [opts] */
constructor(dir, catalog = CATALOG_URL, {readerTTL = DEFAULT_READER_TTL, clusterTTL} = {}) {
this.#catalog = catalog;
this.#dir = dir;
this.#readerTTL = readerTTL;
this.#clusterTTL = clusterTTL; // undefined -> ZimReader's own default
}
async #download(url, destPath) {
@@ -45,11 +53,7 @@ export class ZimManager {
let reader;
try {
reader = await new ZimReader(filepath).open();
return {
name: await reader.metadata('Name'),
date: await reader.metadata('Date'),
title: await reader.metadata('Title'),
};
return await reader.metadata();
} catch {
return null;
} finally {
@@ -59,16 +63,16 @@ export class ZimManager {
async #update(name, catalogEntry, localMatch, force) {
const remoteDate = catalogEntry.updated ? new Date(catalogEntry.updated) : null;
const localDate = localMatch?.meta?.date ? new Date(localMatch.meta.date) : null;
const localDate = localMatch?.meta?.updated ?? null;
if (!force && localMatch && remoteDate && localDate && remoteDate <= localDate)
return {name, status: 'skipped', reason: 'up to date'};
if (!catalogEntry.href) return {name, status: 'skipped', reason: 'missing download link'};
if (!catalogEntry.download) return {name, status: 'skipped', reason: 'missing download link'};
const filename = path.basename(new URL(catalogEntry.href).pathname).replace(/\.meta4$/i, '');
const filename = path.basename(new URL(catalogEntry.download).pathname).replace(/\.meta4$/i, '');
const destPath = path.join(this.#dir, filename);
await this.#download(catalogEntry.href, destPath);
if (localMatch && localMatch.file !== destPath) await fs.promises.unlink(localMatch.file).catch(() => {});
return {name, status: 'updated', file: destPath};
await this.#download(catalogEntry.download, destPath);
if (localMatch && localMatch.file !== filename) await this.#evict(path.join(this.#dir, localMatch.file));
return {name, status: 'updated', file: filename};
}
/** Resolves a file path or catalog `name` to a local file path. */
@@ -79,13 +83,28 @@ export class ZimManager {
const local = await this.list();
const match = local.find(l => l.meta?.name === fileOrName || path.basename(l.file) === fileOrName);
if (!match) throw new Error(`ZIM not found locally: ${fileOrName}`);
return match.file;
return path.join(this.#dir, match.file);
}
/** Closes and drops a cached reader for `file`, if any (used before delete/replace). */
async #evict(file) {
const entry = this.#readers.get(file);
if (!entry) return new ZimReader(file).delete().catch(() => {});
clearTimeout(entry.timer);
this.#readers.delete(file);
await entry.reader.delete();
}
catalog(search, opts) {
return zimCatalog(search, opts);
}
async delete(fileOrName) {
const file = await this.#resolveFile(fileOrName);
await this.#evict(file);
return {file: path.basename(file), status: 'deleted'};
}
/** Checks whether a local ZIM has a newer version in the catalog, without downloading. */
async isOutdated(file) {
const meta = await this.#readMeta(file);
@@ -93,7 +112,7 @@ export class ZimManager {
const catalogEntry = await zimCatalog(meta.name, this.#catalog);
if (!catalogEntry) return {file, upToDate: null, reason: 'missing from catalog'};
const remoteDate = catalogEntry.updated ? new Date(catalogEntry.updated) : null;
const localDate = meta.date ? new Date(meta.date) : null;
const localDate = meta.updated ?? null;
return {file, name: meta.name, upToDate: !!(remoteDate && localDate && remoteDate <= localDate), localDate, remoteDate};
}
@@ -103,7 +122,7 @@ export class ZimManager {
const files = (await fs.promises.readdir(this.#dir)).filter(f => f.endsWith('.zim'));
return Promise.all(files.map(async f => {
const file = path.join(this.#dir, f);
return {file, meta: await this.#readMeta(file)};
return {file: f, ...(await this.#readMeta(file))};
}));
}
@@ -116,7 +135,7 @@ export class ZimManager {
const local = await this.list();
const localMatch = local.find(l => l.meta?.name === name) ?? null;
const catalogEntry = await zimCatalogInfo(name, this.#catalog) || {name, updated: null, href};
const catalogEntry = await zimCatalogInfo(name, this.#catalog) || {name, updated: null, download: href};
return this.#update(name, catalogEntry, localMatch, force);
}
@@ -139,22 +158,43 @@ export class ZimManager {
return results;
}
/** Opens a `ZimReader` for a local ZIM, resolved by file path or catalog `name`. Caller must `.close()` it. */
/** Opens a fresh `ZimReader` for a local ZIM, resolved by file path or catalog `name`. Caller must `.close()` it. */
async open(fileOrName) {
await this.#ensureDir();
const file = await this.#resolveFile(fileOrName);
return new ZimReader(file).open();
let entry = this.#readers.get(file);
if (!entry) {
let pending = this.#opening.get(file);
if (!pending) {
pending = new ZimReader(file, {clusterTTL: this.#clusterTTL}).open();
this.#opening.set(file, pending);
}
let reader;
try {
reader = await pending;
} finally {
this.#opening.delete(file);
}
entry = this.#readers.get(file) ?? {reader};
this.#readers.set(file, entry);
}
clearTimeout(entry.timer);
entry.timer = setTimeout(() => {
this.#readers.delete(file);
entry.reader.close();
}, this.#readerTTL).unref();
return entry.reader;
}
/** Fuzzy-searches titles across every local ZIM in the library, merging & re-ranking hits by score. */
async search(terms, {limit = 10, htmlOnly = true} = {}) {
async search(terms, {limit = 20, htmlOnly = true} = {}) {
const local = await this.list();
const perZim = await Promise.all(local.map(async ({file, meta}) => {
let reader;
try {
reader = await new ZimReader(file).open();
reader = await new ZimReader(path.join(this.#dir, file)).open();
const hits = await reader.search(terms, {limit, htmlOnly});
return hits.map(h => ({...h, file, name: meta?.name}));
return hits.map(h => ({...h, file}));
} catch {
return [];
} finally {

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@@ -1,30 +1,16 @@
'use strict';
import fs from 'node:fs';
import {decompress as lzmaDecompress} from 'lzma1';
import {ZstdCodec} from 'zstd-codec';
import {fuzzyMatch, titleFromUrl} from './utils.js';
import {decompressPool} from './decompress.js';
import {fuzzyMatch, titleFromUrl, kiwixSearch} from './utils.js';
const HEADER_SIZE = 80;
const NS_CONTENT = 'C';
const NS_METADATA = 'M';
const TITLE_SENTINEL = 0xffffffffffffffffn; // Indicator -> ZIM v6+ archives with no title
let zstdStreamingPromise = null;
/** Lazily initialised, shared Zstd streaming decompressor (handles unknown-size frames). */
function getZstd() {
if (!zstdStreamingPromise) {
zstdStreamingPromise = new Promise(resolve => ZstdCodec.run(zstd => resolve(new zstd.Streaming())));
}
return zstdStreamingPromise;
}
/** Rebuilds a full 13-byte "alone" LZMA header from libzim's truncated 5-byte one (unknown size). */
function toLzmaAloneStream(body) {
const header = Buffer.concat([body.subarray(0, 5), Buffer.alloc(8, 0xff)]);
return Buffer.concat([header, body.subarray(5)]);
}
const DEFAULT_CLUSTER_CACHE_MAX = 32;
const DEFAULT_CLUSTER_TTL = 60_000;
/** Native, dependency-light reader for .zim archives. Supports zstd & LZMA cluster compression. */
export class ZimReader {
@@ -32,20 +18,19 @@ export class ZimReader {
#header = null;
#mimeTypes = [];
#hasTitleListing = false;
#clusterCache = new Map(); // clusterNumber -> {data, extended, timer}
#pending = new Map(); // clusterNumber -> Promise, dedupes concurrent misses
#clusterCacheMax;
#clusterTTL;
get articleCount() { return this.#header?.articleCount ?? 0; }
get mediaCount() { return this.#header?.clusterCount ?? 0; }
constructor(path) {
/** @param {{clusterCacheMax?: number, clusterTTL?: number}} [opts] clusterTTL in ms; 0/null disables idle eviction. */
constructor(path, {clusterCacheMax = DEFAULT_CLUSTER_CACHE_MAX, clusterTTL = DEFAULT_CLUSTER_TTL} = {}) {
this.path = path;
}
/** Full O(n) scan over the URL pointer list, used when there's no title index. */
async #allDirents() {
const dirents = [];
for (let i = 0; i < this.#header.articleCount; i++) {
dirents.push(await this.#readDirent(await this.#ptr64(this.#header.urlPtrPos, i)));
}
return dirents;
this.#clusterCacheMax = clusterCacheMax;
this.#clusterTTL = clusterTTL;
}
/** Binary search the URL pointer list for namespace+url. */
@@ -63,7 +48,31 @@ export class ZimReader {
return null;
}
async #getBlob(clusterNumber, blobNumber) {
/** Binary search the title index for an exact title match. */
async #findByTitle(title) {
if (!this.#hasTitleListing) return null;
const q = title.toLowerCase();
let lo = 0, hi = this.#header.articleCount - 1;
while (lo <= hi) {
const mid = (lo + hi) >> 1;
const urlIdx = (await this.#read(this.#header.titlePtrPos + mid * 4, 4)).readUInt32LE(0);
const dirent = await this.#readDirent(await this.#ptr64(this.#header.urlPtrPos, urlIdx));
const t = dirent.title.toLowerCase();
if (t === q) return dirent;
if (t < q) lo = mid + 1; else hi = mid - 1;
}
return null;
}
/** Resets a cluster's idle-eviction timer. No-op when TTL disabled. */
#touch(clusterNumber, entry) {
if (!this.#clusterTTL) return;
clearTimeout(entry.timer);
entry.timer = setTimeout(() => this.#clusterCache.delete(clusterNumber), this.#clusterTTL).unref();
}
/** Fetches + decompresses a cluster exactly once, offloading decompression to the worker pool. */
async #loadCluster(clusterNumber) {
const start = await this.#ptr64(this.#header.clusterPtrPos, clusterNumber);
const isLast = clusterNumber === this.#header.clusterCount - 1;
const end = isLast
@@ -76,14 +85,42 @@ export class ZimReader {
const body = raw.subarray(1);
let data;
if (compType <= 1) data = body;
else if (compType === 4) data = Buffer.from(lzmaDecompress(toLzmaAloneStream(body)));
else if (compType === 5) data = Buffer.from((await getZstd()).decompress(new Uint8Array(body)));
if (compType <= 1) data = Buffer.from(body);
else if (compType === 4 || compType === 5) data = await decompressPool.run({compType, body});
else throw new Error(`Unsupported cluster compression type: ${compType}`);
if (!data) throw new Error(`Cluster ${clusterNumber} failed to decompress (compType ${compType})`);
const readPtr = i => extended ? Number(data.readBigUInt64LE(i * 8)) : data.readUInt32LE(i * 4);
return data.subarray(readPtr(blobNumber), readPtr(blobNumber + 1));
return {data, extended};
}
async #getBlob(clusterNumber, blobNumber) {
let entry = this.#clusterCache.get(clusterNumber);
if (!entry) {
let pending = this.#pending.get(clusterNumber);
if (!pending) {
pending = this.#loadCluster(clusterNumber);
this.#pending.set(clusterNumber, pending);
}
entry = await pending;
this.#pending.delete(clusterNumber);
this.#clusterCache.set(clusterNumber, entry);
if (this.#clusterCache.size > this.#clusterCacheMax) {
const oldestKey = this.#clusterCache.keys().next().value;
clearTimeout(this.#clusterCache.get(oldestKey)?.timer);
this.#clusterCache.delete(oldestKey);
}
}
this.#touch(clusterNumber, entry);
const readPtr = i => entry.extended ? Number(entry.data.readBigUInt64LE(i * 8)) : entry.data.readUInt32LE(i * 4);
return entry.data.subarray(readPtr(blobNumber), readPtr(blobNumber + 1));
}
async #icon(size = 48) {
const page = await this.readPage(`Illustration_${size}x${size}@1`, NS_METADATA)
|| await this.readPage('Favicon', NS_METADATA);
if (!page) return null;
return `data:${page.mimetype};base64,${page.data.toString('base64')}`;
}
async #ptr64(base, index) {
@@ -152,42 +189,59 @@ export class ZimReader {
return this.#readDirent(await this.#ptr64(this.#header.urlPtrPos, dirent.redirectIndex));
}
/** Narrows to dirents near the term's alphabetical position in the title index. */
async #titleIndexCandidates(term) {
const q = term.toLowerCase();
let lo = 0, hi = this.#header.articleCount - 1;
while (lo < hi) {
const mid = (lo + hi) >> 1;
const urlIdx = (await this.#read(this.#header.titlePtrPos + mid * 4, 4)).readUInt32LE(0);
const dirent = await this.#readDirent(await this.#ptr64(this.#header.urlPtrPos, urlIdx));
if (dirent.title.toLowerCase() < q) lo = mid + 1; else hi = mid;
}
// Widen around the prefix match since fuzzy scoring isn't purely alphabetical.
const start = Math.max(0, lo - 50), end = Math.min(this.#header.articleCount, lo + 200);
const dirents = [];
for (let i = start; i < end; i++) {
const urlIdx = (await this.#read(this.#header.titlePtrPos + i * 4, 4)).readUInt32LE(0);
dirents.push(await this.#readDirent(await this.#ptr64(this.#header.urlPtrPos, urlIdx)));
}
return dirents;
}
async close() {
if (this.#fd) await this.#fd.close();
this.#fd = null;
for (const entry of this.#clusterCache.values()) clearTimeout(entry.timer);
this.#clusterCache.clear();
this.#pending.clear();
}
/** Deletes the zim archive. Safe to call on unopened readers. */
async delete() {
await this.close();
await fs.promises.rm(this.path, {force: true});
}
/** Reads an 'M' namespace metadata value (e.g. Name, Date, Title). Returns null if missing. */
async metadata(key) {
const get = async key => {
const page = await this.readPage(key, NS_METADATA);
return page ? page.data.toString('utf8') : null;
};
if(key) return get(key);
const [title, creator, publisher, date, description, language, name, tags] = await Promise.all(
['Title', 'Creator', 'Publisher', 'Date', 'Description', 'Language', 'Name', 'Tags'].map(get)
);
return {
title,
updated: date ? new Date(date) : null,
summary: description,
language,
name,
category: tags ? tags.split(';')[0] || '' : '',
tags: tags ? tags.split(';') : [],
author: creator,
publisher,
articleCount: this.articleCount,
mediaCount: this.mediaCount,
sizeMb: +((await fs.promises.stat(this.path)).size / 1024 / 1024).toFixed(1),
icon: await this.#icon(),
};
}
/** Opens the archive and parses its header + mimetype list. */
async open() {
this.#fd = await fs.promises.open(this.path, 'r');
try {
await this.#readHeader();
await this.#readMimeTypes();
} catch (e) {
await this.#fd.close();
this.#fd = null;
throw e;
}
return this;
}
@@ -211,32 +265,25 @@ export class ZimReader {
/**
* Fuzzy-ranked title search. Accepts comma-separated `terms` the same way the
* catalog search does. Uses the sorted title index when present (binary search
* narrows the candidate window); falls back to a full linear scan otherwise
* (common on ZIM v6+/zimit-generated archives with no title index).
* catalog search does. Uses kiwix-search's embedded fulltext index as a prefilter
* to narrow candidates before fuzzy scoring.
*/
async search(terms, {limit = 20, htmlOnly = true} = {}) {
const termList = String(terms).split(',').map(t => t.trim()).filter(Boolean);
if (!termList.length) return [];
const candidates = (this.#hasTitleListing && this.#header.articleCount > 5000)
? await this.#titleIndexCandidates(termList[0])
: await this.#allDirents();
const titles = await kiwixSearch(this.path, termList.join(' '));
const candidates = (await Promise.all(titles.map(t => this.#findByTitle(t)))).filter(Boolean);
const scored = [];
for (const dirent of candidates) {
if (dirent.namespace !== NS_CONTENT) continue;
if (htmlOnly && !(this.#mimeTypes[dirent.mimetype] || '').startsWith('text/html')) continue;
const urlTitle = titleFromUrl(dirent.url);
const titleScore = fuzzyMatch(dirent.title, ...termList).max;
const urlScore = fuzzyMatch(urlTitle, ...termList).max;
scored.push({
url: dirent.url,
title: dirent.title.length > urlTitle.length ? dirent.title : urlTitle,
namespace: dirent.namespace,
score: Math.max(titleScore, urlScore)
});
scored.push({url: dirent.url, title: dirent.title.length > urlTitle.length ? dirent.title : urlTitle, namespace: NS_CONTENT, score: Math.max(titleScore, urlScore)});
}
return scored.filter(a => a.score > 0).toSorted((a, b) => b.score - a.score).slice(0, limit);
const {summary, mediaCount, articleCount, sizeMb, ...meta} = await this.metadata();
return scored.filter(a => a.score > 0).toSorted((a, b) => b.score - a.score).slice(0, limit).map(a => ({...meta, ...a}));
}
}

View File

@@ -1,3 +1,32 @@
import {execFile} from 'node:child_process';
import path from 'node:path';
import {fileURLToPath} from 'node:url';
import {promisify} from 'node:util';
/**
* Search a ZIM file's fulltext index.
* @param {string} zimPath - Path to the .zim file
* @param {string} pattern - Search terms
* @param {object} [opts]
* @param {boolean} [opts.suggestion] - Suggest titles from partial pattern (completion-style)
* @param {boolean} [opts.spelling] - Suggest spelling-corrected titles
* @returns {Promise<string[]>} Matching article/tag titles
*/
export async function kiwixSearch(zimPath, pattern, opts = {}) {
const execFileAsync = promisify(execFile);
const __dirname = path.dirname(fileURLToPath(import.meta.url));
const BIN_NAME = process.platform === 'win32' ? 'kiwix-search.exe' : 'kiwix-search';
const BIN_PATH = path.join(__dirname, '..', 'bin', BIN_NAME);
const args = [];
if (opts.suggestion) args.push('-s');
if (opts.spelling) args.push('--spelling');
args.push(zimPath, pattern);
const {stdout} = await execFileAsync(BIN_PATH, args);
return stdout.split('\n').map(line => line.trim()).filter(Boolean);
}
export function levenshtein(a, b) {
const m = a.length, n = b.length;
if (!m) return n;
@@ -20,12 +49,6 @@ export function similarity(a, b) {
return 1 - levenshtein(a, b) / Math.max(a.length, b.length, 1);
}
/**
* Scores `text` against a single lowercased `term`. Substring containment always wins.
* Otherwise, only rescues genuine typos: requires the same leading letter and a tight
* absolute edit-distance cap, so unrelated words can't win purely on coincidental
* letter overlap (e.g. "Viennese" vs "diannes").
*/
function scoreAgainst(text, term) {
if (text.includes(term)) return 1 - (text.length - term.length) / text.length * 0.3;
if (!text.length || !term.length || text[0] !== term[0]) return 0;