DIGEST - Upstash Documentation

Use DIGEST to get the digest of a string value.

The reply is a 16-character lowercase hexadecimal XXH3 digest of the stored bytes, null when the key does not exist, and an error when the value is not a string. It is a fast non-cryptographic hash, meant for change detection rather than for security.

Comparing digests lets a client tell whether a large value has changed without transferring it, for instance to decide whether a cached copy is still current. The same digest can be passed to the conditional forms of SET (IFDEQ, IFDNE) and DELEX, which turns it into a compact compare-and-set token for large values. DIGEST is an Upstash extension.

Syntax#

DIGEST <key>

Arguments#

Argument	Required	Repeatable	Description
`key`	Yes	No	String key whose value should be hashed.

Important points#

The reply is a 16-character lowercase hexadecimal XXH3 digest of the stored string bytes.
A missing key returns null. A key containing a non-string value returns WRONGTYPE.

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	Bulk string or Null bulk string or null array
RESP3	Bulk string or Null

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

DIGEST lock:job-1

@upstash/redis

Note

This command is not supported yet in @upstash/redis.

upstash_redis

Note

This command is not supported yet in upstash_redis.

ioredis

import Redis from "ioredis";const redis = new Redis(process.env.REDIS_URL!);const result = await redis.call("DIGEST", "lock:job-1");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.digest("lock:job-1");console.log(result);

redis-py

import osimport redisclient = redis.from_url(os.environ["REDIS_URL"])result = client.execute_command("DIGEST", "lock:job-1")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.Digest(context.Background(), "lock:job-1").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.digestKey("lock:job-1");  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.digest("lock:job-1")?;    println!("{result:?}");    Ok(())}