2025-03-24 22:56:10 +01:00

107 lines
3.7 KiB
JavaScript

"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.CachedFileSystem = void 0;
const path_1 = require("path");
const graceful_fs_1 = __importDefault(require("graceful-fs"));
const async_sema_1 = require("async-sema");
const fsReadFile = graceful_fs_1.default.promises.readFile;
const fsReadlink = graceful_fs_1.default.promises.readlink;
const fsStat = graceful_fs_1.default.promises.stat;
class CachedFileSystem {
fileCache;
statCache;
symlinkCache;
fileIOQueue;
constructor({ cache, fileIOConcurrency, }) {
this.fileIOQueue = new async_sema_1.Sema(fileIOConcurrency);
this.fileCache = cache?.fileCache ?? new Map();
this.statCache = cache?.statCache ?? new Map();
this.symlinkCache = cache?.symlinkCache ?? new Map();
if (cache) {
cache.fileCache = this.fileCache;
cache.statCache = this.statCache;
cache.symlinkCache = this.symlinkCache;
}
}
async readlink(path) {
const cached = this.symlinkCache.get(path);
if (cached !== undefined)
return cached;
// This is not awaiting the response, so that the cache is instantly populated and
// future calls serve the Promise from the cache
const readlinkPromise = this.executeFileIO(path, this._internalReadlink);
this.symlinkCache.set(path, readlinkPromise);
return readlinkPromise;
}
async readFile(path) {
const cached = this.fileCache.get(path);
if (cached !== undefined)
return cached;
// This is not awaiting the response, so that the cache is instantly populated and
// future calls serve the Promise from the cache
const readFilePromise = this.executeFileIO(path, this._internalReadFile);
this.fileCache.set(path, readFilePromise);
return readFilePromise;
}
async stat(path) {
const cached = this.statCache.get(path);
if (cached !== undefined)
return cached;
// This is not awaiting the response, so that the cache is instantly populated and
// future calls serve the Promise from the cache
const statPromise = this.executeFileIO(path, this._internalStat);
this.statCache.set(path, statPromise);
return statPromise;
}
async _internalReadlink(path) {
try {
const link = await fsReadlink(path);
// also copy stat cache to symlink
const stats = this.statCache.get(path);
if (stats)
this.statCache.set((0, path_1.resolve)(path, link), stats);
return link;
}
catch (e) {
if (e.code !== 'EINVAL' && e.code !== 'ENOENT' && e.code !== 'UNKNOWN')
throw e;
return null;
}
}
async _internalReadFile(path) {
try {
return (await fsReadFile(path)).toString();
}
catch (e) {
if (e.code === 'ENOENT' || e.code === 'EISDIR') {
return null;
}
throw e;
}
}
async _internalStat(path) {
try {
return await fsStat(path);
}
catch (e) {
if (e.code === 'ENOENT') {
return null;
}
throw e;
}
}
async executeFileIO(path, fileIO) {
await this.fileIOQueue.acquire();
try {
return fileIO.call(this, path);
}
finally {
this.fileIOQueue.release();
}
}
}
exports.CachedFileSystem = CachedFileSystem;