/*
File Name:  Store.go
Copyright:  2021 Peernet s.r.o.
Author:     Peter Kleissner

Simple key-value store interface.
*/

package store

import (
	"time"
)

// Store is the interface for implementing the storage mechanism for the DHT.
type Store interface {
	// Set stores the key-value pair.
	Set(key []byte, data []byte) error

	// StoreExpire stores the key-value pair and deletes it after the expiration time.
	// If key-value already exists, it will be overwritten and the new expiration time applies.
	StoreExpire(key []byte, data []byte, expiration time.Time) error

	// Get returns the value for the key if present.
	Get(key []byte) (data []byte, found bool)

	// Delete deletes a key-value pair.
	Delete(key []byte)

	// ExpireKeys is called to delete all keys that are marked for expiration.
	ExpireKeys()

	// Count returns the total number of records stored.
	Count() uint64

	// Iterate iterates over all records.
	Iterate(callback func(key, value []byte))
}