Redis Microservices
Redis 6.2 or newer is required because recovery uses Streams consumer-group commands including automatic claiming. Each command subject maps to a deterministic Stream. The client subscribes to a unique temporary Pub/Sub reply channel before appending the command. Events share a configured Stream.
Replicas with the same service_name share consumer groups. One replica handles
each command; each service group receives every event, with one replica handling
it inside that group.
#![allow(unused)]
fn main() {
let options = RedisTransportOptions::new("redis://127.0.0.1/")
.service_name("billing")
.event_stream("caelix:events")
.dead_letter_stream("caelix:dead");
}Options
| Method | Default | Meaning |
|---|---|---|
new(server) | required | Redis URL |
service_name(name) | none | required stable consumer-group identity |
event_stream(key) | caelix:events | shared event Stream |
dead_letter_stream(key) | none | distinct final-failure Stream |
rpc_timeout(duration) | 5 s | complete request/reply deadline |
max_request_bytes(n) | 1 MiB | command envelope limit; minimum 1 |
max_response_bytes(n) | 1 MiB | response envelope limit; minimum 256 |
max_event_bytes(n) | 1 MiB | event envelope limit; minimum 1 |
max_handler_concurrency(n) | 64 | concurrent handler bound; minimum 1 |
shutdown_timeout(duration) | 10 s | graceful task deadline |
max_event_deliveries(n) | 5 | final delivery attempt; minimum 1 |
event_retry_delay(duration) | 1 s | idle interval before event reclaim; minimum 10 ms |
command_recovery_delay(duration) | 30 s | idle interval before abandoned command reclaim; minimum 10 ms |
approximate_max_event_entries(n) | unlimited | opt-in MAXLEN ~ event trimming |
An expired command is acknowledged without invoking user code. Pending commands
from a failed replica are reclaimed after command_recovery_delay; handlers
must therefore be idempotent even though a healthy request normally executes
once. Events are at least once and retry through pending-entry recovery.
Event retention is unlimited unless trimming is enabled. Approximate trimming can delete entries still pending in a slower service group; set it only with a retention policy covering the slowest consumer. A dead-letter Stream must be non-empty and differ from the event Stream. Shutdown stops intake, drains within the configured timeout, and runs lifecycle hooks.