44 lines
1.8 KiB
JavaScript
44 lines
1.8 KiB
JavaScript
import { promises } from 'fs';
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import { LRUCache } from './lru-cache';
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/**
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* Module-level LRU singleton for disk cache eviction.
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* Initialized once on first `set()`, shared across all consumers.
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* Once resolved, the promise stays resolved — subsequent calls just await the cached result.
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*/ let _diskLRUPromise = null;
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/**
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* Initialize or return the module-level LRU for disk cache eviction.
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* Concurrent calls are deduplicated via the shared promise.
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*
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* @param cacheDir - The directory where cached files are stored
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* @param maxDiskSize - Maximum disk cache size in bytes
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* @param readEntries - Callback to scan existing cache entries (format-agnostic)
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*/ export async function getOrInitDiskLRU(cacheDir, maxDiskSize, readEntries, evictEntry) {
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if (!_diskLRUPromise) {
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_diskLRUPromise = (async ()=>{
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let maxSize = maxDiskSize;
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if (typeof maxSize === 'undefined') {
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// Ensure cacheDir exists before checking disk space
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await promises.mkdir(cacheDir, {
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recursive: true
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});
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// Since config was not provided, default to 50% of available disk space
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const { bavail, bsize } = await promises.statfs(cacheDir);
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maxSize = Math.floor(bavail * bsize / 2);
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}
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const lru = new LRUCache(maxSize, (size)=>size, (cacheKey)=>evictEntry(cacheDir, cacheKey));
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const entries = await readEntries(cacheDir);
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for (const entry of entries){
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lru.set(entry.key, entry.size);
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}
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return lru;
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})();
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}
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return _diskLRUPromise;
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}
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/**
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* Reset the module-level LRU singleton. Exported for testing only.
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*/ export function resetDiskLRU() {
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_diskLRUPromise = null;
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}
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//# sourceMappingURL=disk-lru-cache.external.js.map
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