cache

type Cache interface {
	io.Closer

	Name() string

	// Set saves entry with the given key,
	// it returns an ErrEntryTooBig when entry is too big.
	Set(ctx context.Context, key string, entry []byte) error

	// Delete removes the given key.
	Delete(ctx context.Context, key string) ([]byte, error)

	// Get reads entry for the given key,
	// it returns an ErrEntryNotFound when no entry exists for the given key.
	Get(ctx context.Context, key string) ([]byte, error)
}

type FileConfig struct {
	// Namespace indicates the operating workspace.
	Namespace string
	// EntryMaxAge indicates the maximum lifetime of each entry,
	// default is 15 mins.
	EntryMaxAge time.Duration
	// LazyEntryEviction indicates to evict an expired entry at next peeking,
	// by default, a background looping tries to evict expired entries per 3 mins.
	LazyEntryEviction bool
	// Buckets indicates the bucket number of cache,
	// value must be a power of two,
	// default is 12.
	Buckets int
}

type MemoryConfig struct {
	// Namespace indicates the operating workspace.
	Namespace string
	// EntryMaxAge indicates the maximum lifetime of each entry,
	// default is 15 mins.
	EntryMaxAge time.Duration
	// LazyEntryEviction indicates to evict an expired entry at next peeking,
	// by default, a background looping tries to evict expired entries per 3 mins.
	LazyEntryEviction bool
	// Buckets indicates the bucket number of cache,
	// value must be a power of two,
	// default is 64.
	Buckets int
	// BucketCapacity indicates the maximum MB of each bucket,
	// default is 1 MB.
	BucketCapacity int
	// LazyBucketCapacityScale indicates to scale when the current bucket is not enough to put a new entry,
	// by default, create the bucket with the given capacity to avoid any array copying.
	// It's worth noticing that the bucket capacity can not exceed even configured LazyBucketCapacityScale to true.
	LazyBucketCapacityScale bool
}