Strings

String commands read and write whole values, counters and byte ranges. The methods below are on the Redis service.

Example (Typing a Conditional Write and a Counter)

import { Effect } from "effect";

import { Redis } from "@effect-kit/redis";

const program = Effect.gen(function* () {
  const redis = yield* Redis;

  const claimed = yield* redis.set("lock:report", "worker-1", { condition: "NX" });
         
const claimed: boolean
  const views = yield* redis.incrby("views", 5);
        
const views: bigint
  const previous = yield* redis.set("mode", "fast", { get: true });
          
const previous: Option<Uint8Array<ArrayBufferLike>>

  return { claimed, views, previous };
});

get returns Option<string> and getBytes returns Option<Uint8Array>. Counters return bigint. set returns void, a boolean when you pass a condition, and the previous value when you pass get: true.

MethodsCopy Anchor Link

SetOptionsCopy Anchor Link

redis.set takes SetOptions. The type of the options decides the reply type, as shown in SetResult. redis.setKey takes WriteSetOptions, which is SetOptions without get.

expiryAfter(duration) turns an Effect Duration into an expiry value. It rejects durations shorter than one millisecond.

Example (Setting a Key With a Duration)

import { Duration, Effect } from "effect";

import { Redis, expiryAfter } from "@effect-kit/redis";

const program = Effect.gen(function* () {
  const redis = yield* Redis;

  const expiry = yield* expiryAfter(Duration.minutes(5));
  yield* redis.set("session:abc", "user-42", { expiry });
});

IncrementExpiryOptionsCopy Anchor Link

redis.increx takes IncrementExpiryOptions. redis.increxFloat takes FloatIncrementExpiryOptions, where increment is required and values are number | string.

Other option typesCopy Anchor Link

• MultiSetOptions for redis.msetex: { condition?: "NX" | "XX"; expiry?: SetExpiry }.
• DeleteCondition for redis.delex: { type: "IFEQ" | "IFNE" | "IFDEQ" | "IFDNE"; value: string | Uint8Array }.
• Expiry for redis.getex: { type: "EX" | "PX" | "EXAT" | "PXAT"; value: number | bigint } | { type: "PERSIST" }.
• LcsMatches is the redis.lcsMatches reply: { length: bigint; matches: ReadonlyArray<LcsMatch> }.

Typed keysCopy Anchor Link

redis.getKey and redis.setKey read and write values through a RedisKey codec. See Typed values.