cache

cache

Temporary key-value storage with a single Cache interface and two backends: Redis and in-memory.

Install

go get github.com/fatkulnurk/foundation/cache@v0.3.0

API

type Cache interface {
    Set(ctx context.Context, key string, value any, ttlSeconds int) error
    Get(ctx context.Context, key string) (string, error)
    Delete(ctx context.Context, key string) error
    Has(ctx context.Context, key string) (bool, error)
}

• ttlSeconds <= 0 means no expiry (local) / Redis zero TTL semantics as implemented.
• Keys are stored as Prefix + key when Config.Prefix is set.
• Get returns cache.ErrNotFound when the key is missing or expired (local).

Local cache

cfg := &cache.Config{Prefix: "myapp:"}
c := cache.NewLocalCache(cfg)
if lc, ok := c.(*cache.LocalCache); ok {
    defer lc.Close() // stops background janitor
}

_ = c.Set(ctx, "user:1", "Ada", 60)
v, err := c.Get(ctx, "user:1")

Suitable for tests, single-process apps, and data that must not be shared across instances. Expired keys are removed on access and by a background janitor.

Redis cache

import "github.com/redis/go-redis/v9"

rdb := redis.NewClient(&redis.Options{Addr: "localhost:6379"})
c := cache.NewRedisCache(&cache.Config{Prefix: "myapp:"}, rdb)

_ = c.Set(ctx, "user:1", "Ada", 60)

Use Redis when multiple processes/servers must share the same cache.

Config

Field	Env (via LoadConfig)	Description
Prefix	CACHE_PREFIX	Optional key prefix (e.g. myapp:)

cfg := cache.LoadConfig()

When to use which

	Local	Redis
Shared across nodes	No	Yes
Extra dependency	None	Redis server
Best for	Dev, tests, single instance	Production multi-instance

See also

• Root README
• Example: example/main.go