cof

A lightweight, generic, thread-safe in-memory key-value cache for Go with TTL-based expiration and automatic background cleanup.

Features

• Generic -- store any value type via Go generics
• Thread-safe -- all operations are protected by a sync.RWMutex
• TTL expiration -- default TTL per cache, per-item override with PutWithTTL
• Automatic cleanup -- background goroutine periodically removes expired entries
• Lazy expiration -- Get, Pop, Has, Len, and Keys never return expired items even between cleanups

Install

go get github.com/leodeim/cof

Requires Go 1.23+.

Quick start

package main

import (
    "fmt"
    "time"

    "github.com/leodeim/cof"
)

func main() {
    c, err := cof.Init[string](
        cof.TTL(5 * time.Minute),
        cof.CleanInterval(1 * time.Minute),
    )
    if err != nil {
        panic(err)
    }
    defer c.Stop()

    c.Put("greeting", "hello, world!")

    v, ok := c.Get("greeting")
    fmt.Println(v, ok) // hello, world! true
}

API

Creating a cache

c, err := cof.Init[ValueType](opts ...cof.Option)

Options

Option	Default	Description
cof.TTL(d)	15 min	Default TTL for entries. Pass 0 to disable expiration.
cof.CleanInterval(d)	1 min	How often the cleaner runs. Pass 0 to disable background cleanup.

Operations

Method	Description
Put(key, value)	Insert/update with the default TTL
PutWithTTL(key, value, ttl)	Insert/update with a custom TTL (0 = no expiry)
Get(key) (T, bool)	Retrieve a value; returns false if missing or expired
Pop(key) (T, bool)	Retrieve and delete; returns false if missing or expired
Delete(key)	Remove an entry
Has(key) bool	Check existence (expired entries return false)
Len() int	Count of live entries
Keys() []string	Sorted slice of live keys
Clear()	Remove all entries (keeps the cleaner running)
Stop()	Remove all entries and stop the background goroutine

License

MIT