@nasriya/cachify
Version:
A lightweight, extensible in-memory caching library for storing anything, with built-in TTL and customizable cache types.
72 lines (71 loc) • 2.29 kB
JavaScript
"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
const crypto_1 = __importDefault(require("crypto"));
const helpers_1 = __importDefault(require("../helpers"));
const stream_1 = require("stream");
class DecryptStream extends stream_1.Transform {
#_key;
#_ivExtractHandler = helpers_1.default.createExtractIVHandler();
#_chunkProcessor = helpers_1.default.createChunkProcessor();
#_iv = null;
#_decipher = null;
#_handler = null;
constructor(key) {
super();
if (key.length !== 32) {
throw new Error('Key must be 32 bytes (256 bits) long');
}
this.#_key = key;
}
#decrept(data) {
return this.#_decipher.update(data);
}
#setHandler(callback) {
this.#_handler = helpers_1.default.createCallbackHandler(callback, this.#decrept.bind(this));
}
#processChunk(chunk) {
return this.#_chunkProcessor(chunk, this.#_handler);
}
_transform(chunk, encoding, callback) {
this.#setHandler(callback);
try {
if (Buffer.isBuffer(this.#_iv)) {
return this.#processChunk(chunk);
}
const res = this.#_ivExtractHandler(chunk);
if (!res.found) {
return callback();
}
this.#_iv = res.iv;
this.#_decipher = crypto_1.default.createDecipheriv('aes-256-cbc', this.#_key, this.#_iv);
return this.#processChunk(res.rest);
}
catch (error) {
callback(error);
}
}
_flush(callback) {
this.#setHandler(callback);
try {
if (!this.#_decipher) {
// No data processed at all
return callback();
}
this.#_chunkProcessor.flush(this.#_handler);
const final = this.#_decipher.final();
this.push(final);
}
catch (err) {
callback(err);
}
finally {
this.#_handler = null;
this.#_iv = null;
this.#_decipher = null;
}
}
}
exports.default = DecryptStream;