To implement a concurrent cache using sync.Map in Golang, follow these steps:
Step 1: Import the required packages
import (
"sync"
"time"
)
Step 2: Define the Cache struct
type Cache struct {
cacheMap *sync.Map
}
Step 3: Define the Set method to add or update a key-value pair in the cache
func (c *Cache) Set(key, value interface{}) {
c.cacheMap.Store(key, value)
}
Step 4: Define the Get method to retrieve a value by key from the cache
func (c *Cache) Get(key interface{}) (interface{}, bool) {
return c.cacheMap.Load(key)
}
Step 5: Define the Delete method to remove a key-value pair from the cache
func (c *Cache) Delete(key interface{}) {
c.cacheMap.Delete(key)
}
Step 6: Define the CleanupExpired method to periodically delete expired key-value pairs from the cache
func (c *Cache) CleanupExpired(duration time.Duration) {
ticker := time.NewTicker(duration)
go func() {
for range ticker.C {
c.cacheMap.Range(func(key, value interface{}) bool {
// Implement the logic to check if the key-value pair has expired
// If expired, delete the key-value pair from the cache
return true
})
}
}()
}
Step 7: Create an instance of the Cache struct and use its methods to interact with the cache
func main() {
cache := &Cache{
cacheMap: &sync.Map{},
}
cache.Set("key1", "value1")
cache.Set("key2", "value2")
value, ok := cache.Get("key1")
if ok {
fmt.Println(value)
}
cache.Delete("key2")
}
Note: Replace the comment in Step 6 with the logic to check if a key-value pair has expired. You can use the time package's functions like time.Now() and duration comparisons to implement the expiration logic.