useMultiFileAuthState

Store authentication state across multiple files for efficient session management

The useMultiFileAuthState function provides a file-based implementation of authentication state storage. It’s more efficient than single-file storage but recommended for development/bot use only.

While more efficient than single-file storage, this is not recommended for production applications. Consider implementing authentication state storage with a proper SQL or NoSQL database for production use.

Function Signature

const useMultiFileAuthState = async (
  folder: string
): Promise<{ 
  state: AuthenticationState; 
  saveCreds: () => Promise<void> 
}>

Parameters

folder · string · required

Path to the folder where authentication state files will be stored. The folder will be created if it doesn’t exist.

Returns

Returns a Promise that resolves to an object with:

state · AuthenticationState · required

The authentication state object containing credentials and keys

Show properties

creds · AuthenticationCreds

Authentication credentials loaded from creds.json or newly initialized

keys · SignalKeyStore

Key store implementation with file-based persistence

Show methods

get · async function

Retrieve keys by type and IDs from JSON files

async (type: string, ids: string[]) => {
  // Reads files like: pre-key-1.json, session-abc.json
  // Returns: { [id]: value }
}

set · async function

Store keys to JSON files, delete if value is null

async (data: SignalDataSet) => {
  // Writes/deletes files like: pre-key-1.json, session-abc.json
}

saveCreds · () => Promise<void> · required

Function to persist credentials to disk. Call this after credential updates to save changes.

await saveCreds() // Writes to creds.json

Usage Example

import { useMultiFileAuthState } from '@whiskeysockets/baileys'

const { state, saveCreds } = await useMultiFileAuthState('./auth_info')

// Use the state when creating a socket connection
const sock = makeWASocket({
  auth: state,
  // ... other options
})

// Listen for credential updates and save them
sock.ev.on('creds.update', saveCreds)

File Structure

The function creates the following file structure:

auth_info/
├── creds.json                    # Main credentials
├── pre-key-1.json               # Individual pre-keys
├── pre-key-2.json
├── session-123456789.json        # Session data
├── app-state-sync-key-xyz.json  # App state keys
└── ...

Key Features

File Locking

The implementation uses per-file mutex locks to prevent race conditions when reading/writing files concurrently:

const fileLocks = new Map<string, Mutex>()
const getFileLock = (path: string): Mutex => {
  let mutex = fileLocks.get(path)
  if (!mutex) {
    mutex = new Mutex()
    fileLocks.set(path, mutex)
  }
  return mutex
}

File Name Sanitization

Special characters in key IDs are sanitized for safe file system usage:

• / → __
• : → -

Automatic Initialization

If creds.json doesn’t exist, new credentials are automatically initialized using initAuthCreds().

Special Handling for App State Keys

App state sync keys are deserialized using protobuf:

if (type === 'app-state-sync-key' && value) {
  value = proto.Message.AppStateSyncKeyData.fromObject(value)
}

Error Handling

The function will throw an error if a non-directory file exists at the specified folder path.

if (folderInfo && !folderInfo.isDirectory()) {
  throw new Error(
    `found something that is not a directory at ${folder}, ` +
    `either delete it or specify a different location`
  )
}

Related

• AuthenticationState - Authentication state types
• makeCacheableSignalKeyStore - Add caching to key stores