Memory Cache

Memory Cache

go-zero’s collection.Cache provides a thread-safe, size-bounded, TTL-evicting in-process cache backed by LRU eviction.

Basic Usage

import "github.com/zeromicro/go-zero/core/collection"

c := collection.NewCache(time.Minute)   // default TTL = 1 minute

// Set
c.Set("user:42", user)

// Get
val, ok := c.Get("user:42")
if ok {
    return val.(*User), nil
}

With Custom TTL per Entry

c.SetWithExpire("session:abc", session, 30*time.Minute)

Take (Read-Through)

val, err := c.Take("user:42", func() (any, error) {
    return db.QueryUser(42)
})

Take is safe for concurrent callers — only one goroutine executes the loader function for the same key (singleflight semantics).

Configuration

c := collection.NewCache(
    time.Minute,
    collection.WithLimit(10000),   // max 10 000 items
)

When to Use

• Hot data that fits in memory and changes infrequently
• Local deduplication of identical concurrent reads
• Complement to Redis cache for L1/L2 layering