tachyon-expire-cache

TachyonExpireCache is a cache class that allows you to add expiration for data.

It implements the generic IAsyncCache interface from '@luolapeikko/cache-types' and uses the IStorageDriver interface from the "tachyon-drive" to support different storage drivers.

Installation

``bash
npm install tachyon-expire-cache
`

Validation and serialization type

`typescript
type CacheMap = Map<
Key,
{ data: Payload; expires: number | undefined }
>;
`

Usage

Example with FileStorageDriver and BufferSerializer with zod validation

`typescript
import { TachyonExpireCache, CacheMap } from "tachyon-expire-cache";
import { IPersistSerializer } from "tachyon-drive";
import { FileStorageDriver } from "tachyon-drive-node-fs";

// type CachePayload = {data: Payload; expires: number | undefined};
function cachePayloadSchema(data: z.Schema) {
return z.object({
data,
expires: z.number().optional(),
});
}

// type CacheMap = Map>
const bufferSerializer: IPersistSerializer, Buffer> = {
serialize: (data: CacheMap) =>
Buffer.from(JSON.stringify(Array.from(data))),
deserialize: (buffer: Buffer) => new Map(JSON.parse(buffer.toString())),
validator: (data: CacheMap) =>
z.map(z.string(), cachePayloadSchema(z.string())).safeParse(data).success,
};
const driver = new FileStorageDriver(
{ fileName: "./cache.json", name: "FileStorageDriver" },
bufferSerializer,
);
const cache = new TachyonExpireCache(
{ name: "Some-Cache-Name" },
driver,
);

await cache.set("key", "value", new Date(Date.now() + 1000));

await cache.get("key"); // 'value'

await cache.has("key"); // true

await cache.delete("key"); // true

await cache.clear();

await cache.size(); // number of items in cache
``