node-redis/docs/client-configuration.md

createClient configuration

Property	Default	Description
url		redis[s]://[[username][:password]@][host][:port][/db-number] (see redis and rediss IANA registration for more details)
socket		Socket connection properties. Unlisted net.connect properties (and tls.connect) are also supported
socket.port	6379	Redis server port
socket.host	'localhost'	Redis server hostname
socket.family	0	IP Stack version (one of 4 | 6 | 0)
socket.path		Path to the UNIX Socket
socket.connectTimeout	5000	Connection timeout (in milliseconds)
socket.noDelay	true	Toggle Nagle's algorithm
socket.keepAlive	true	Toggle keep-alive functionality
socket.keepAliveInitialDelay	5000	If set to a positive number, it sets the initial delay before the first keepalive probe is sent on an idle socket
socket.tls		See explanation and examples below
socket.reconnectStrategy	Exponential backoff with a maximum of 2000 ms; plus 0-200 ms random jitter.	A function containing the Reconnect Strategy logic
username		ACL username (see ACL guide)
password		ACL password or the old "--requirepass" password
name		Client name (see CLIENT SETNAME)
database		Redis database number (see SELECT command)
modules		Included Redis Modules
scripts		Script definitions (see Lua Scripts)
functions		Function definitions (see Functions)
commandsQueueMaxLength		Maximum length of the client's internal command queue
disableOfflineQueue	false	Disables offline queuing, see FAQ
readonly	false	Connect in READONLY mode
legacyMode	false	Maintain some backwards compatibility (see the Migration Guide)
isolationPoolOptions		See the Isolated Execution Guide
pingInterval		Send PING command at interval (in ms). Useful with "Azure Cache for Redis"

Reconnect Strategy

When the socket closes unexpectedly (without calling .quit()/.disconnect()), the client uses reconnectStrategy to decide what to do. The following values are supported:

1. false -> do not reconnect, close the client and flush the command queue.
2. number -> wait for X milliseconds before reconnecting.
3. (retries: number, cause: Error) => false | number | Error -> number is the same as configuring a number directly, Error is the same as false, but with a custom error.

By default the strategy uses exponential backoff, but it can be overwritten like so:

createClient({
  socket: {
    reconnectStrategy: retries => {
        // Generate a random jitter between 0 – 200 ms:
        const jitter = Math.floor(Math.random() * 200);
        // Delay is an exponential back off, (times^2) * 50 ms, with a maximum value of 2000 ms:
        const delay = Math.min(Math.pow(2, retries) * 50, 2000);

        return delay + jitter;
    }
  }
});

TLS

To enable TLS, set socket.tls to true. Below are some basic examples.

For configuration options see tls.connect and tls.createSecureContext, as those are the underlying functions used by this library.

Create a SSL client

createClient({
  socket: {
    tls: true,
    ca: '...',
    cert: '...'
  }
});

Create a SSL client using a self-signed certificate

createClient({
  socket: {
    tls: true,
    rejectUnauthorized: false,
    cert: '...'
  }
});