React weak argument using JSON based cache function for Server Component: useful to assign argument as object, array or any serializable values.

object-cache.ts

import hash from 'object-hash';

export type ObjectCacheFunction<A extends unknown[], V> = (...args: A) => V;
const objectMap = cache(() => new Map<string, any[]>());

export const objectCache = <A extends unknown[], V>(fn: ObjectCacheFunction<A, V>): ObjectCacheFunction<A, V> => {
  const map = objectMap();
  return new Proxy(
    cache((s: string) => fn(...(map.get(s) as A))),
    {
      apply(target, _, args) {
        const key = hash(args);
        map.set(key, args);
        return target(key);
      },
    }
  ) as unknown as ObjectCacheFunction<A, V>;
};

weak-cache.ts

export type WeakCacheFunction<A extends unknown[], V> = (...args: A) => V;

export const weakCache = <A extends unknown[], V>(fn: WeakCacheFunction<A, V>): WeakCacheFunction<A, V> => {
  return new Proxy(
    cache((s: string) => fn(...JSON.parse(s))),
    {
      apply(target, _, args) {
        // use serializable verification for safety argument cache!
        //if (!isSerializable(args))
        //  throw new TypeError('weakCache error: arguments must be serializable for check arguments equality.');
        return target(JSON.stringify(args));
      },
    }
  ) as unknown as WeakCacheFunction<A, V>;
};

// How to use: just same as react cache! and use it in Server Component.
const weakCachedFn = weakCache((a: string, b:number, c: { foo: string }, d: number[]) => {
  console.log("I'll show you when all serializable argument value based cache hit!", a, b, c, d);
});