redis
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A modern, high performance Redis client
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# Node-Redis
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[](https://codecov.io/gh/redis/node-redis)
[](https://github.com/redis/node-redis/blob/master/LICENSE)
[](https://discord.gg/redis)
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node-redis is a modern, high performance [Redis](https://redis.io) client for Node.js.
## How do I Redis?
[Learn for free at Redis University](https://university.redis.com/)
[Build faster with the Redis Launchpad](https://launchpad.redis.com/)
[Try the Redis Cloud](https://redis.com/try-free/)
[Dive in developer tutorials](https://developer.redis.com/)
[Join the Redis community](https://redis.com/community/)
[Work at Redis](https://redis.com/company/careers/jobs/)
## Installation
Start a redis via docker:
```bash
docker run -p 6379:6379 -d redis:8.0-rc1
```
To install node-redis, simply:
```bash
npm install redis
```
> "redis" is the "whole in one" package that includes all the other packages. If you only need a subset of the commands,
> you can install the individual packages. See the list below.
## Packages
| Name | Description |
| ---------------------------------------------- | ------------------------------------------------------------------------------------------- |
| [`redis`](../redis) | The client with all the ["redis-stack"](https://github.com/redis-stack/redis-stack) modules |
| [`@redis/client`](../client) | The base clients (i.e `RedisClient`, `RedisCluster`, etc.) |
| [`@redis/bloom`](../bloom) | [Redis Bloom](https://redis.io/docs/data-types/probabilistic/) commands |
| [`@redis/json`](../json) | [Redis JSON](https://redis.io/docs/data-types/json/) commands |
| [`@redis/search`](../search) | [RediSearch](https://redis.io/docs/interact/search-and-query/) commands |
| [`@redis/time-series`](../time-series) | [Redis Time-Series](https://redis.io/docs/data-types/timeseries/) commands |
| [`@redis/entraid`](../entraid) | Secure token-based authentication for Redis clients using Microsoft Entra ID |
> Looking for a high-level library to handle object mapping?
> See [redis-om-node](https://github.com/redis/redis-om-node)!
## Usage
### Basic Example
```typescript
import { createClient } from "redis";
const client = await createClient()
.on("error", (err) => console.log("Redis Client Error", err))
.connect();
await client.set("key", "value");
const value = await client.get("key");
client.destroy();
```
The above code connects to localhost on port 6379. To connect to a different host or port, use a connection string in
the format `redis[s]://[[username][:password]@][host][:port][/db-number]`:
```typescript
createClient({
url: "redis://alice:foobared@awesome.redis.server:6380",
});
```
You can also use discrete parameters, UNIX sockets, and even TLS to connect. Details can be found in
the [client configuration guide](../../docs/client-configuration.md).
To check if the the client is connected and ready to send commands, use `client.isReady` which returns a boolean.
`client.isOpen` is also available. This returns `true` when the client's underlying socket is open, and `false` when it
isn't (for example when the client is still connecting or reconnecting after a network error).
### Redis Commands
There is built-in support for all of the [out-of-the-box Redis commands](https://redis.io/commands). They are exposed
using the raw Redis command names (`HSET`, `HGETALL`, etc.) and a friendlier camel-cased version (`hSet`, `hGetAll`,
etc.):
```typescript
// raw Redis commands
await client.HSET("key", "field", "value");
await client.HGETALL("key");
// friendly JavaScript commands
await client.hSet("key", "field", "value");
await client.hGetAll("key");
```
Modifiers to commands are specified using a JavaScript object:
```typescript
await client.set("key", "value", {
EX: 10,
NX: true,
});
```
Replies will be transformed into useful data structures:
```typescript
await client.hGetAll("key"); // { field1: 'value1', field2: 'value2' }
await client.hVals("key"); // ['value1', 'value2']
```
`Buffer`s are supported as well:
```typescript
const client = createClient().withTypeMapping({
[RESP_TYPES.BLOB_STRING]: Buffer
});
await client.hSet("key", "field", Buffer.from("value")); // 'OK'
await client.hGet("key", "field"); // { field: <Buffer 76 61 6c 75 65> }
```
### Unsupported Redis Commands
If you want to run commands and/or use arguments that Node Redis doesn't know about (yet!) use `.sendCommand()`:
```typescript
await client.sendCommand(["SET", "key", "value", "NX"]); // 'OK'
await client.sendCommand(["HGETALL", "key"]); // ['key1', 'field1', 'key2', 'field2']
```
### Transactions (Multi/Exec)
Start a [transaction](https://redis.io/topics/transactions) by calling `.multi()`, then chaining your commands. When
you're done, call `.exec()` and you'll get an array back with your results:
```typescript
await client.set("another-key", "another-value");
const [setKeyReply, otherKeyValue] = await client
.multi()
.set("key", "value")
.get("another-key")
.exec(); // ['OK', 'another-value']
```
You can also [watch](https://redis.io/topics/transactions#optimistic-locking-using-check-and-set) keys by calling
`.watch()`. Your transaction will abort if any of the watched keys change.
### Blocking Commands
In v4, `RedisClient` had the ability to create a pool of connections using an "Isolation Pool" on top of the "main"
connection. However, there was no way to use the pool without a "main" connection:
```javascript
const client = await createClient()
.on("error", (err) => console.error(err))
.connect();
await client.ping(client.commandOptions({ isolated: true }));
```
In v5 we've extracted this pool logic into its own class—`RedisClientPool`:
```javascript
const pool = await createClientPool()
.on("error", (err) => console.error(err))
.connect();
await pool.ping();
```
### Pub/Sub
See the [Pub/Sub overview](../../docs/pub-sub.md).
### Scan Iterator
[`SCAN`](https://redis.io/commands/scan) results can be looped over
using [async iterators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol/asyncIterator):
```typescript
for await (const key of client.scanIterator()) {
// use the key!
await client.get(key);
}
```
This works with `HSCAN`, `SSCAN`, and `ZSCAN` too:
```typescript
for await (const { field, value } of client.hScanIterator("hash")) {
}
for await (const member of client.sScanIterator("set")) {
}
for await (const { score, value } of client.zScanIterator("sorted-set")) {
}
```
You can override the default options by providing a configuration object:
```typescript
client.scanIterator({
TYPE: "string", // `SCAN` only
MATCH: "patter*",
COUNT: 100,
});
```
### Disconnecting
The `QUIT` command has been deprecated in Redis 7.2 and should now also be considered deprecated in Node-Redis. Instead
of sending a `QUIT` command to the server, the client can simply close the network connection.
`client.QUIT/quit()` is replaced by `client.close()`. and, to avoid confusion, `client.disconnect()` has been renamed to
`client.destroy()`.
```typescript
client.destroy();
```
### Auto-Pipelining
Node Redis will automatically pipeline requests that are made during the same "tick".
```typescript
client.set("Tm9kZSBSZWRpcw==", "users:1");
client.sAdd("users:1:tokens", "Tm9kZSBSZWRpcw==");
```
Of course, if you don't do something with your Promises you're certain to
get [unhandled Promise exceptions](https://nodejs.org/api/process.html#process_event_unhandledrejection). To take
advantage of auto-pipelining and handle your Promises, use `Promise.all()`.
```typescript
await Promise.all([
client.set("Tm9kZSBSZWRpcw==", "users:1"),
client.sAdd("users:1:tokens", "Tm9kZSBSZWRpcw=="),
]);
```
### Programmability
See the [Programmability overview](../../docs/programmability.md).
### Clustering
Check out the [Clustering Guide](../../docs/clustering.md) when using Node Redis to connect to a Redis Cluster.
### Events
The Node Redis client class is an Nodejs EventEmitter and it emits an event each time the network status changes:
| Name | When | Listener arguments |
| ----------------------- | ---------------------------------------------------------------------------------- | --------------------------------------------------------- |
| `connect` | Initiating a connection to the server | _No arguments_ |
| `ready` | Client is ready to use | _No arguments_ |
| `end` | Connection has been closed (via `.disconnect()`) | _No arguments_ |
| `error` | An error has occurred—usually a network issue such as "Socket closed unexpectedly" | `(error: Error)` |
| `reconnecting` | Client is trying to reconnect to the server | _No arguments_ |
| `sharded-channel-moved` | See [here](../../docs/pub-sub.md#sharded-channel-moved-event) | See [here](../../docs/pub-sub.md#sharded-channel-moved-event) |
> :warning: You **MUST** listen to `error` events. If a client doesn't have at least one `error` listener registered and
> an `error` occurs, that error will be thrown and the Node.js process will exit. See the [ > `EventEmitter` docs](https://nodejs.org/api/events.html#events_error_events) for more details.
> The client will not emit [any other events](../../docs/v3-to-v4.md#all-the-removed-events) beyond those listed above.
## Supported Redis versions
Node Redis is supported with the following versions of Redis:
| Version | Supported |
| ------- | ------------------ |
| 8.0.z | :heavy_check_mark: |
| 7.4.z | :heavy_check_mark: |
| 7.2.z | :heavy_check_mark: |
| < 7.2 | :x: |
> Node Redis should work with older versions of Redis, but it is not fully tested and we cannot offer support.
## Migration
- [From V3 to V4](../../docs/v3-to-v4.md)
- [From V4 to V5](../../docs/v4-to-v5.md)
- [V5](../../docs/v5.md)
## Contributing
If you'd like to contribute, check out the [contributing guide](../../CONTRIBUTING.md).
Thank you to all the people who already contributed to Node Redis!
[](https://github.com/redis/node-redis/graphs/contributors)
## License
This repository is licensed under the "MIT" license. See [LICENSE](../../LICENSE).