RPUSHX to add elements to the tail of a list only when the list already exists.
Nothing happens and the reply is 0 when the key does not exist, and no key is created. Use it when producers should append to a queue only while it is alive, for example when the list is created by a consumer that is currently attached, so that writes to a queue nobody is reading do not silently pile up.
Syntax
Arguments
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.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 TLSREDIS_URL from the Upstash console. REST examples use UPSTASH_REDIS_REST_URL and UPSTASH_REDIS_REST_TOKEN.
Redis CLI
Redis CLI
@upstash/redis
@upstash/redis
upstash_redis
upstash_redis
ioredis
ioredis
node-redis
node-redis
redis-py
redis-py
go-redis
go-redis
jedis
jedis
redis-rs
redis-rs