@avanio/expire-cache/dist/index.d.mts

Typescript/Javascript cache with expiration

import { EventEmitter } from 'events';
import { LogMapInfer, MapLogger, ILoggerLike } from '@avanio/logger-like';
import { CacheEventsMap, ICacheWithEvents } from '@luolapeikko/cache-types';

/**
 * Callback type for when entries are expired or cleared
 */
type ICacheOnClearCallback<Payload, Key = string> = (entries: Map<Key, Payload>) => void;
/**
 * Synchronous cache interface
 * @deprecated Use ```import {type ICache} from '@luolapeikko/cache-types';``` instead.
 * @example
 * function foo(cache: ICache<string>) {
 *   const value = cache.get('key');
 *   cache.set('key', 'value');
 *   cache.has('key'); // true
 *   cache.delete('key');
 *   cache.clear();
 *   cache.size(); // 0
 * }
 */
interface ICache<Payload, Key = string> {
    /**
     * Gets a value from the cache
     * @param key - The key to get the value for
     * @returns The cached value or undefined if not found
     */
    get(key: Key): Payload | undefined;
    /**
     * Sets a value in the cache with an optional expiration date
     * @param key - The key to set the value for
     * @param data - The data to set in the cache
     * @param expires - The optional expiration date for the cache entry
     */
    set(key: Key, value: Payload, expires?: Date): void;
    /**
     * Deletes a value from the cache
     * @param key - The key to delete the value for
     * @returns {boolean} True if the value was deleted, false otherwise
     */
    delete(key: Key): boolean;
    /**
     * Checks if a key exists in the cache
     * @param key - The key to check for
     * @returns {boolean} True if the key exists in the cache, false otherwise
     */
    has(key: Key): boolean;
    /**
     * Get key expiration Date object or undefined if not found in cache
     * @param key - The key to get the expiration for
     * @returns {Date | undefined} Date object or undefined if not found in cache
     */
    expires(key: Key): Date | undefined;
    /**
     * Clear all cached values
     */
    clear(): void;
    /**
     * Gets the number of items in the cache
     * @returns {number} The number of items in the cache
     */
    size(): number;
    /**
     * Called when a entries are expired, deleted or cleared
     */
    onClear(callback: ICacheOnClearCallback<Payload, Key>): void;
    /**
     * Returns an iterator of key, value pairs for every entry in the cache.
     * @example
     * for(const [key, value] of cache.entries()) {
     *   console.log(key, value);
     * }
     */
    entries(): IterableIterator<[Key, Payload]>;
    /**
     * Returns an iterator of keys in the cache.
     * @example
     * for(const key of cache.keys()) {
     *   console.log(key);
     * }
     */
    keys(): IterableIterator<Key>;
    /**
     * Returns an iterator of values in the cache.
     * @example
     * for(const value of cache.values()) {
     *   console.log(value);
     * }
     */
    values(): IterableIterator<Payload>;
}

/**
 * Async callback type for when entries are expired or cleared
 */
type IAsyncCacheOnClearCallback<Payload, Key = string> = (entries: Map<Key, Payload>) => Promise<void>;
/**
 * Asynchronous cache interface
 * @deprecated Use ```import {type IAsyncCache} from '@luolapeikko/cache-types';``` instead.
 * @example
 * function foo(cache: IAsyncCache<string>) {
 *   const value = await cache.get('key');
 *   await cache.set('key', 'value');
 *   await cache.has('key'); // true
 *   await cache.delete('key');
 *   await cache.clear();
 *   await cache.size(); // 0
 * }
 */
interface IAsyncCache<Payload, Key = string> {
    /**
     * Gets a value from the cache
     * @param key - The key to get the value for
     * @returns {Promise<Payload | undefined>} Promise of the cached value or undefined if not found
     */
    get(key: Key): Promise<Payload | undefined>;
    /**
     * Sets a value in the cache with an optional expiration date
     * @param key - The key to set the value for
     * @param data - The data to set in the cache
     * @param expires - The optional expiration date for the cache entry
     * @returns {Promise<void>} Promise of void
     */
    set(key: Key, value: Payload, expires?: Date): Promise<void>;
    /**
     * Deletes a value from the cache
     * @param key - The key to delete the value for
     * @returns {Promise<boolean>} Promise of true if the value was deleted, false otherwise
     */
    delete(key: Key): Promise<boolean>;
    /**
     * Checks if a key exists in the cache
     * @param key - The key to check for
     * @returns {Promise<boolean>} Promise of true if the key exists in the cache, false otherwise
     */
    has(key: Key): Promise<boolean>;
    /**
     * Get key expiration Date object or undefined if not found in cache
     * @param key - The key to get the expiration for
     * @returns {Promise<Date | undefined>} Promise of Date object or undefined if not found in cache
     */
    expires(key: Key): Promise<Date | undefined>;
    /**
     * Clear all cached values
     */
    clear(): Promise<void>;
    /**
     * Gets the number of items in the cache
     * @returns {Promise<number>} Promise of the number of items in the cache
     */
    size(): Promise<number>;
    /**
     * Called when a entries are expired, deleted or cleared
     */
    onClear(callback: IAsyncCacheOnClearCallback<Payload, Key>): void;
    /**
     * Returns an async iterator of key, value pairs for every entry in the cache.
     * @example
     * for await (const [key, value] of cache.entries()) {
     *   console.log(key, value);
     * }
     */
    entries(): AsyncIterableIterator<[Key, Payload]>;
    /**
     * Async iterator for cache keys
     * @example
     * for await (const key of cache.keys()) {
     *   console.log(key);
     * }
     */
    keys(): AsyncIterableIterator<Key>;
    /**
     * Async iterator for cache values
     * @example
     * for await (const value of cache.values()) {
     *   console.log(value);
     * }
     */
    values(): AsyncIterableIterator<Payload>;
}

/**
 * A type that represents both synchronous and asynchronous cache interfaces.
 * This type can be used to create functions that work with both types of cache interfaces.
 * @deprecated Use ```import {type IAsyncCache} from '@luolapeikko/cache-types';``` instead.
 * @example
 * function foo(cache: ICacheOrAsync<string>) {
 *   const value = await cache.get('key');
 *   await cache.set('key', 'value');
 *   await cache.has('key'); // true
 *   await cache.delete('key');
 *   await cache.clear();
 *   await cache.size(); // 0
 * }
 */
type ICacheOrAsync<Payload, Key = string> = ICache<Payload, Key> | IAsyncCache<Payload, Key>;

/**
 * The default log mapping for the ExpireCache class.
 * This maps each method to a log level, allowing you to control the logging output.
 * By default, all logs are disabled (None level)
 * @example
 * const cache = new ExpireCache<string>(console, {
 *   get: LogLevel.Info,
 *   set: LogLevel.Debug,
 *   delete: LogLevel.Warn,
 * });
 */
declare const defaultLogMap$2: {
    readonly cleanExpired: 0;
    readonly clear: 0;
    readonly constructor: 0;
    readonly delete: 0;
    readonly expires: 0;
    readonly get: 0;
    readonly has: 0;
    readonly onExpire: 0;
    readonly set: 0;
    readonly size: 0;
};
type ExpireCacheLogMapType = LogMapInfer<typeof defaultLogMap$2>;
/**
 * ExpireCache class that implements the ICache interface with value expiration and expires on read operations
 * @template Payload - The type of the cached data
 * @template Key - (optional) The type of the cache key (default is string)
 * @since v0.6.5
 */
declare class ExpireCache<Payload, Key = string> extends EventEmitter<CacheEventsMap<Payload, Key>> implements ICacheWithEvents<Payload, Key> {
    private readonly cache;
    private readonly cacheTtl;
    readonly logger: MapLogger<ExpireCacheLogMapType>;
    private defaultExpireMs;
    /**
     * Creates a new instance of the ExpireCache class
     * @param logger - The logger to use (optional)
     * @param logMapping - The log mapping to use (optional). Default is all logging disabled
     * @param defaultExpireMs - The default expiration time in milliseconds (optional)
     */
    constructor(logger?: ILoggerLike, logMapping?: Partial<ExpireCacheLogMapType>, defaultExpireMs?: number);
    set(key: Key, data: Payload, expires?: Date): void;
    get(key: Key): Payload | undefined;
    has(key: Key): boolean;
    expires(key: Key): Date | undefined;
    delete(key: Key): boolean;
    clear(): void;
    size(): number;
    entries(): IterableIterator<[Key, Payload]>;
    keys(): IterableIterator<Key>;
    values(): IterableIterator<Payload>;
    /**
     * Sets the default expiration time in milliseconds
     * @param expireMs - The default expiration time in milliseconds
     */
    setExpireMs(expireMs: number | undefined): void;
    /**
     * Cleans expired cache entries
     */
    private cleanExpired;
    private notifyExpires;
    private getExpireDate;
}

/**
 * The default log mapping for the ExpireCache class.
 * This maps each method to a log level, allowing you to control the logging output.
 * By default, all logs are disabled (None level)
 * @example
 * const cache = new ExpireCache<string>(console, {
 *   get: LogLevel.Info,
 *   set: LogLevel.Debug,
 *   delete: LogLevel.Warn,
 * });
 */
declare const defaultLogMap$1: {
    cleanExpired: 0;
    clear: 0;
    constructor: 0;
    delete: 0;
    expires: 0;
    get: 0;
    has: 0;
    onExpire: 0;
    set: 0;
    size: 0;
};
type ExpireTimeoutCacheLogMapType = LogMapInfer<typeof defaultLogMap$1>;
/**
 * ExpireCache class that implements the ICache interface with value expiration and expires with setTimeout
 * @template Payload - The type of the cached data
 * @template Key - (optional) The type of the cache key (default is string)
 * @since v0.6.5
 */
declare class ExpireTimeoutCache<Payload, Key = string> extends EventEmitter<CacheEventsMap<Payload, Key>> implements ICacheWithEvents<Payload, Key> {
    private readonly cache;
    private readonly cacheTimeout;
    readonly logger: MapLogger<ExpireTimeoutCacheLogMapType>;
    private defaultExpireMs;
    /**
     * Creates a new instance of the ExpireTimeoutCache class
     * @param logger - The logger to use (optional)
     * @param logMapping - The log mapping to use (optional). Default is all logging disabled
     * @param defaultExpireMs - The default expiration time in milliseconds (optional)
     */
    constructor(logger?: ILoggerLike, logMapping?: Partial<ExpireTimeoutCacheLogMapType>, defaultExpireMs?: number);
    set(key: Key, data: Payload, expires?: Date): void;
    get(key: Key): Payload | undefined;
    has(key: Key): boolean;
    expires(key: Key): Date | undefined;
    delete(key: Key): boolean;
    clear(): void;
    size(): number;
    entries(): IterableIterator<[Key, Payload]>;
    keys(): IterableIterator<Key>;
    values(): IterableIterator<Payload>;
    /**
     * Set the default expiration time in milliseconds
     * @param expireMs - The default expiration time in milliseconds
     */
    setExpireMs(expireMs: number | undefined): void;
    private clearTimeout;
    private notifyExpires;
    private getExpireDate;
    private handleExpiredCallback;
    private handleTimeoutSetup;
}

type TierType<Data, Tier extends string> = {
    tier: Tier;
    data: Data;
};
/**
 * Helper type to build cache tier getter methods
 */
type GetCacheTier<T extends TierType<unknown, string>[], Key> = {
    [K in T[number] as `get${Capitalize<K['tier']>}`]: (key: Key, cache: T[number]) => Promise<K['data'] | undefined> | K['data'] | undefined;
};
type TierStatusRecord<T extends TierType<unknown, string>[]> = Record<T[number]['tier'], number>;
type TierStatusInitialRecord<T extends TierType<unknown, string>[]> = Record<T[number]['tier'], 0>;
type TieredCacheStatus<T extends TierType<unknown, string>[]> = {
    size: number;
    tiers: TierStatusRecord<T>;
};
type MultiTierCacheEvents<T extends TierType<unknown, string>[], Key> = {
    update: [status: Readonly<TieredCacheStatus<T>>];
    set: [Iterable<Key>];
    delete: [Iterable<Key>];
    clear: [];
};
declare const defaultLogMap: {
    readonly clear: 0;
    readonly clearTimeoutKey: 0;
    readonly constructor: 0;
    readonly delete: 0;
    readonly get: 0;
    readonly has: 0;
    readonly runTimeout: 0;
    readonly set: 0;
    readonly setTimeout: 0;
    readonly size: 0;
};
type TieredCacheLogMapType = LogMapInfer<typeof defaultLogMap>;
/**
 * Multi tier cache with timeout support to change tier based on timeout
 * @since v0.6.0
 */
declare abstract class TieredCache<Tiers extends TierType<unknown, string>[], TimeoutEnum extends number, Key> extends EventEmitter<MultiTierCacheEvents<Tiers, Key>> {
    abstract readonly cacheName: string;
    protected readonly cache: Map<Key, Tiers[number]>;
    private readonly cacheTimeout;
    readonly logger: MapLogger<TieredCacheLogMapType>;
    private statusData;
    constructor(logger?: ILoggerLike, logMapping?: Partial<ExpireCacheLogMapType>);
    /**
     * Get cache entry from cache
     * @param key - cache key
     * @param tier - cache tier
     * @param timeout - optional update to new timeout for cache entry (if not provided, default timeout for tier will be used)
     * @returns - promise that resolves when cache entry is set
     */
    get<T extends Tiers[number]>(key: Key, tier: T['tier'], timeout?: TimeoutEnum): Promise<Promise<T['data'] | undefined> | T['data'] | undefined>;
    /**
     * Set cache entry
     * @param key - cache key
     * @param tier - cache tier
     * @param data - cache data
     * @param timeout - optional timeout for cache entry. Else timeout will be checked from handleTimeoutValue or default timeout for tier.
     */
    set<T extends Tiers[number]>(key: Key, tier: T['tier'], data: T['data'], timeout?: TimeoutEnum): Promise<void>;
    /**
     * Set multiple cache entries
     * @param tier - cache tier
     * @param entries - iterable of key, data pairs
     * @param timeout - optional timeout for cache entry. Else timeout will be checked from handleTimeoutValue or default timeout for tier.
     */
    setEntries<T extends Tiers[number]>(tier: T['tier'], entries: Iterable<[Key, T['data']]>, timeout?: TimeoutEnum): Promise<void>;
    /**
     * Get tier type for current key
     */
    getTier(key: Key): Tiers[number]['tier'] | undefined;
    /**
     * Iterate this.cache values and use handleCacheEntry to get data
     * @param tier
     */
    tierValues(tier: Tiers[number]['tier']): AsyncIterable<Tiers[number]['data']>;
    tierEntries(tier: Tiers[number]['tier']): AsyncIterable<[Key, Tiers[number]['data']]>;
    keys(): Iterable<Key>;
    has(key: Key): boolean;
    size(): number;
    clear(): void;
    delete(key: Key): boolean;
    deleteKeys(keys: Iterable<Key>): number;
    status(): Readonly<TieredCacheStatus<Tiers>>;
    protected buildStatus(rebuild: boolean): Readonly<TieredCacheStatus<Tiers>>;
    /**
     * Internal helper to set cache entry and set timeout
     * @param key - cache entry key
     * @param tier - cache entry tier
     * @param data - cache entry data
     * @param timeout - timeout value, optional
     */
    protected handleSetValue<T extends Tiers[number]>(key: Key, tier: T['tier'], data: T['data'], timeout?: TimeoutEnum): Promise<void>;
    /**
     * Internal helper to delete cache entry and cancel its timeout
     * @param key - cache entry key
     * @returns true if entry was deleted, false if not found
     */
    protected handleDeleteValue(key: Key): boolean;
    private logCacheName;
    private setTimeout;
    private clearTimeoutKey;
    private clearAllTimeouts;
    private runTimeout;
    protected abstract handleCacheEntry<T extends Tiers[number]>(key: Key, tier: T['tier'], cache: Tiers[number] | undefined): Promise<T['data'] | undefined> | T['data'] | undefined;
    /**
     * this return new timeout value for cached entry based on tier (or undefined if tier doesn't have timeout)
     * @example
     * // if tier not care about data and just want to return default timeouts
     * protected handleTimeoutValue<T extends DateCacheTiers[number]>(key: Key, tier: T['type'], _data: T['data']) {
     *   return this.handleTierDefaultTimeout(tier); // else make logic based on data (i.e. newer data should have longer timeout)
     * }
     */
    protected abstract handleTimeoutValue<T extends Tiers[number]>(key: Key, tier: T['tier'], data: T['data']): Promise<number | undefined> | number | undefined;
    /**
     * this handle should change value of cache entry to another shape and return next tier default timeout (can also delete entry)
     */
    protected abstract handleTierTimeout(key: Key): Promise<number | undefined> | number | undefined;
    /**
     * If request didn't specify timeout, this method should return default timeout for tier or undefined if tier doesn't have timeout.
     */
    protected abstract handleTierDefaultTimeout(type: Tiers[number]['tier']): TimeoutEnum | undefined;
    /**
     * Build initial status data for cache
     * @example
     * protected getInitialStatusData(): Readonly<TierStatusInitialRecord<DateCacheTiers>>  {
     * 	return {model: 0, object: 0, stringValue: 0} as const;
     * }
     */
    protected abstract getInitialStatusData(): Readonly<TierStatusInitialRecord<Tiers>>;
}

export { ExpireCache, type ExpireCacheLogMapType, ExpireTimeoutCache, type ExpireTimeoutCacheLogMapType, type GetCacheTier, type IAsyncCache, type IAsyncCacheOnClearCallback, type ICache, type ICacheOnClearCallback, type ICacheOrAsync, type TierStatusInitialRecord, type TierStatusRecord, type TierType, TieredCache, type TieredCacheLogMapType, type TieredCacheStatus };