PUBLISH - Upstash Documentation

Use PUBLISH to send a message to a channel.

The reply is the number of subscribers the message was delivered to, counting both channel and pattern subscribers, so a reply of 0 means nobody was listening. Delivery is fire and forget: messages are not stored and a client that is not connected at that moment never sees them, so use streams when messages must survive a disconnect or be replayed.

Publishing works over both the REST API and a TCP connection, while subscribing requires a TCP connection.

Syntax#

PUBLISH <channel> <message>

Arguments#

Argument	Required	Repeatable	Description
`<channel>`	Yes	No	Channel name.
`<message>`	Yes	No	Message payload.

Response#

The reply reports the result of the operation. Error replies have the same shape in RESP2 and RESP3 and are surfaced as exceptions by the SDKs below.

Protocol	Reply
RESP2	Integer
RESP3	Integer

Note

Client libraries often decode bulk strings, maps, sets, and numeric strings into language-native values. The table describes the Redis wire reply.

Examples#

TCP examples use the TLS REDIS_URL from the Upstash console. REST examples use UPSTASH_REDIS_REST_URL and UPSTASH_REDIS_REST_TOKEN.

Redis CLI

PUBLISH events hello

@upstash/redis

import { Redis } from "@upstash/redis";const redis = Redis.fromEnv();const listeners = await redis.publish("my-channel", "my-message");

upstash_redis

from upstash_redis import Redisredis = Redis.from_env()result = redis.publish("events", "hello")print(result)

ioredis

import Redis from "ioredis";const redis = new Redis(process.env.REDIS_URL!);const result = await redis.publish("events", "hello");console.log(result);

node-redis

import { createClient } from "redis";const client = await createClient({ url: process.env.REDIS_URL })  .on("error", console.error)  .connect();const result = await client.publish("events", "hello");console.log(result);

redis-py

import osimport redisclient = redis.from_url(os.environ["REDIS_URL"])result = client.publish("events", "hello")print(result)

go-redis

package mainimport (    "context"    "fmt"    "os"    "github.com/redis/go-redis/v9")func main() {    opts, err := redis.ParseURL(os.Getenv("REDIS_URL"))    if err != nil {        panic(err)    }    client := redis.NewClient(opts)    result, err := client.Publish(context.Background(), "events", "hello").Result()    if err != nil {        panic(err)    }    fmt.Println(result)}

jedis

import java.net.URI;import redis.clients.jedis.Jedis;try (Jedis jedis = new Jedis(new URI(System.getenv("REDIS_URL")))) {  Object result = jedis.publish("events", "hello");  System.out.println(result);}

redis-rs

use redis::TypedCommands;fn main() -> redis::RedisResult<()> {    let url = std::env::var("REDIS_URL").expect("REDIS_URL is not set");    let client = redis::Client::open(url)?;    let mut connection = client.get_connection()?;    let result = connection.publish("events", "hello")?;    println!("{result:?}");    Ok(())}