agsamantha/node_modules/langchain/dist/storage/file_system.cjs

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2024-10-02 15:15:21 -05:00
"use strict";
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
var desc = Object.getOwnPropertyDescriptor(m, k);
if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
desc = { enumerable: true, get: function() { return m[k]; } };
}
Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
o["default"] = v;
});
var __importStar = (this && this.__importStar) || function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
__setModuleDefault(result, mod);
return result;
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.LocalFileStore = void 0;
const fs = __importStar(require("node:fs/promises"));
const path = __importStar(require("node:path"));
const stores_1 = require("@langchain/core/stores");
/**
* File system implementation of the BaseStore using a dictionary. Used for
* storing key-value pairs in the file system.
* @example
* ```typescript
* const store = await LocalFileStore.fromPath("./messages");
* await store.mset(
* Array.from({ length: 5 }).map((_, index) => [
* `message:id:${index}`,
* new TextEncoder().encode(
* JSON.stringify(
* index % 2 === 0
* ? new AIMessage("ai stuff...")
* : new HumanMessage("human stuff..."),
* ),
* ),
* ]),
* );
* const retrievedMessages = await store.mget(["message:id:0", "message:id:1"]);
* console.log(retrievedMessages.map((v) => new TextDecoder().decode(v)));
* for await (const key of store.yieldKeys("message:id:")) {
* await store.mdelete([key]);
* }
* ```
*
* @security **Security Notice** This file store
* can alter any text file in the provided directory and any subfolders.
* Make sure that the path you specify when initializing the store is free
* of other files.
*/
class LocalFileStore extends stores_1.BaseStore {
constructor(fields) {
super(fields);
Object.defineProperty(this, "lc_namespace", {
enumerable: true,
configurable: true,
writable: true,
value: ["langchain", "storage"]
});
Object.defineProperty(this, "rootPath", {
enumerable: true,
configurable: true,
writable: true,
value: void 0
});
this.rootPath = fields.rootPath;
}
/**
* Read and parse the file at the given path.
* @param key The key to read the file for.
* @returns Promise that resolves to the parsed file content.
*/
async getParsedFile(key) {
// Validate the key to prevent path traversal
if (!/^[a-zA-Z0-9_\-:.]+$/.test(key)) {
throw new Error("Invalid key. Only alphanumeric characters, underscores, hyphens, colons, and periods are allowed.");
}
try {
const fileContent = await fs.readFile(this.getFullPath(key));
if (!fileContent) {
return undefined;
}
return fileContent;
// eslint-disable-next-line @typescript-eslint/no-explicit-any
}
catch (e) {
// File does not exist yet.
// eslint-disable-next-line no-instanceof/no-instanceof
if ("code" in e && e.code === "ENOENT") {
return undefined;
}
throw new Error(`Error reading and parsing file at path: ${this.rootPath}.\nError: ${JSON.stringify(e)}`);
}
}
/**
* Writes the given key-value pairs to the file at the given path.
* @param fileContent An object with the key-value pairs to be written to the file.
*/
async setFileContent(content, key) {
try {
await fs.writeFile(this.getFullPath(key), content);
}
catch (error) {
throw new Error(`Error writing file at path: ${this.getFullPath(key)}.\nError: ${JSON.stringify(error)}`);
}
}
/**
* Returns the full path of the file where the value of the given key is stored.
* @param key the key to get the full path for
*/
getFullPath(key) {
try {
const keyAsTxtFile = `${key}.txt`;
// Validate the key to prevent path traversal
if (!/^[a-zA-Z0-9_.\-/]+$/.test(key)) {
throw new Error(`Invalid characters in key: ${key}`);
}
const fullPath = path.resolve(this.rootPath, keyAsTxtFile);
const commonPath = path.resolve(this.rootPath);
if (!fullPath.startsWith(commonPath)) {
throw new Error(`Invalid key: ${key}. Key should be relative to the root path. ` +
`Root path: ${this.rootPath}, Full path: ${fullPath}`);
}
return fullPath;
}
catch (e) {
throw new Error(`Error getting full path for key: ${key}.\nError: ${String(e)}`);
}
}
/**
* Retrieves the values associated with the given keys from the store.
* @param keys Keys to retrieve values for.
* @returns Array of values associated with the given keys.
*/
async mget(keys) {
const values = [];
for (const key of keys) {
const fileContent = await this.getParsedFile(key);
values.push(fileContent);
}
return values;
}
/**
* Sets the values for the given keys in the store.
* @param keyValuePairs Array of key-value pairs to set in the store.
* @returns Promise that resolves when all key-value pairs have been set.
*/
async mset(keyValuePairs) {
await Promise.all(keyValuePairs.map(([key, value]) => this.setFileContent(value, key)));
}
/**
* Deletes the given keys and their associated values from the store.
* @param keys Keys to delete from the store.
* @returns Promise that resolves when all keys have been deleted.
*/
async mdelete(keys) {
await Promise.all(keys.map((key) => fs.unlink(this.getFullPath(key))));
}
/**
* Asynchronous generator that yields keys from the store. If a prefix is
* provided, it only yields keys that start with the prefix.
* @param prefix Optional prefix to filter keys.
* @returns AsyncGenerator that yields keys from the store.
*/
async *yieldKeys(prefix) {
const allFiles = await fs.readdir(this.rootPath);
const allKeys = allFiles.map((file) => file.replace(".txt", ""));
for (const key of allKeys) {
if (prefix === undefined || key.startsWith(prefix)) {
yield key;
}
}
}
/**
* Static method for initializing the class.
* Preforms a check to see if the directory exists, and if not, creates it.
* @param path Path to the directory.
* @returns Promise that resolves to an instance of the class.
*/
static async fromPath(rootPath) {
try {
// Verifies the directory exists at the provided path, and that it is readable and writable.
await fs.access(rootPath, fs.constants.R_OK | fs.constants.W_OK);
}
catch (_) {
try {
// Directory does not exist, create it.
await fs.mkdir(rootPath, { recursive: true });
}
catch (error) {
throw new Error(`An error occurred creating directory at: ${rootPath}.\nError: ${JSON.stringify(error)}`);
}
}
return new this({ rootPath });
}
}
exports.LocalFileStore = LocalFileStore;