@naturalcycles/js-lib
Version:
Standard library for universal (browser + Node.js) javascript
68 lines (67 loc) • 2.67 kB
TypeScript
import type { AnyObject, UnixTimestamp } from '../types.js';
import { MISS } from '../types.js';
export type MemoSerializer = (args: any[]) => any;
export declare const jsonMemoSerializer: MemoSerializer;
export interface MemoCacheOptions {
/**
* If set (and if it's implemented by the driver) - will set expiry TTL for each key of the batch.
* E.g EXAT in Redis.
*/
expireAt?: UnixTimestamp;
}
export interface MemoCache<KEY = any, VALUE = any> {
has: (k: KEY) => boolean;
/**
* `get` return signature doesn't contain `undefined`,
* because `undefined` is a valid VALUE to store in the Cache.
* `undefined` does NOT mean cache miss.
* Cache misses are checked by calling `has` method instead.
*/
get: (k: KEY) => VALUE;
set: (k: KEY, v: VALUE, opt?: MemoCacheOptions) => void;
/**
* Clear is only called when `_getMemoCache().clear()` is called.
* Otherwise the Cache is "persistent" (never cleared).
*/
clear: () => void;
}
export interface AsyncMemoCache<KEY = any, VALUE = any> {
/**
* MISS symbol indicates the ABSENCE of value in the Cache.
* You can safely store `undefined` or `null` values in the Cache,
* they will not be interpreted as a cache miss, because there is a special MISS symbol for that.
*/
get: (k: KEY) => Promise<VALUE | typeof MISS>;
set: (k: KEY, v: VALUE, opt?: MemoCacheOptions) => Promise<void>;
/**
* Clear is only called when `_getAsyncMemo().clear()` is called.
* Otherwise the Cache is "persistent" (never cleared).
*/
clear: () => Promise<void>;
}
export declare class MapMemoCache<KEY = any, VALUE = any> implements MemoCache<KEY, VALUE> {
private m;
has(k: KEY): boolean;
get(k: KEY): VALUE;
set(k: KEY, v: VALUE): void;
clear(): void;
}
/**
* Implementation of AsyncMemoCache backed by a synchronous Map.
* Doesn't have a practical use except testing,
* because the point of AsyncMemoCache is to have an **async** backed cache.
*/
export declare class MapAsyncMemoCache<KEY = any, VALUE = any> implements AsyncMemoCache<KEY, VALUE> {
private delay;
constructor(delay?: number);
private m;
get(k: KEY): Promise<VALUE | typeof MISS>;
set(k: KEY, v: VALUE): Promise<void>;
clear(): Promise<void>;
}
/**
* Generic override of Typescript's built in legacy MethodDecorator, that
* allows us to infer the parameters of the decorated method from the parameters
* of a decorator.
*/
export type MethodDecorator<T> = (target: AnyObject, propertyKey: string | symbol, descriptor: TypedPropertyDescriptor<T>) => TypedPropertyDescriptor<T> | undefined;