Runtime

In-memory map. Forgets everything when the page unloads. Two instances on the same page have independent stores. Backed by a synchronous Map under the hood, but every public method still returns a Promise to satisfy the shared CacheDriverInterface.

Signature

import { RunTimeDriver } from "@mongez/cache";

class RunTimeDriver extends BaseCacheEngine implements CacheDriverInterface {
  public data: Map<string, { value: any; expiresAt?: number }>;
}

The driver overrides getItem / setItem / removeItem to talk to this.data directly, and overrides convertValue / parseValue to no-ops since the in-memory store doesn’t need JSON.

data is a Map, not a plain object: cache keys are caller-supplied, and on a plain object __proto__ / constructor / toString resolve through the prototype chain instead of being treated as data. Reach into it with data.get(key) / data.set(key, value) / data.delete(key) — it was a plain object before v1.4.0.

Usage

import cache, { RunTimeDriver, setCacheConfigurations } from "@mongez/cache";

setCacheConfigurations({
  driver: new RunTimeDriver(),
});

await cache.set("name", "Hasan");
await cache.get("name");                  // "Hasan"
// Reload — gone.

Or two managers, two stores:

const a = new RunTimeDriver();
const b = new RunTimeDriver();
await a.set("name", "from-a");
await b.set("name", "from-b");
await a.get("name");                      // "from-a"
await b.get("name");                      // "from-b"

TTL

Works the same as the storage-backed drivers — await cache.set(key, value, expiresAfterSeconds). A read past the window returns the default and drops the entry.

await cache.set("ttl.test", "abc", 60);
// ... 61 seconds later ...
await cache.get("ttl.test", null);        // null — entry has been removed

SSR

This is the safe default when localStorage / sessionStorage aren’t available:

const driver = typeof window === "undefined"
  ? new RunTimeDriver()
  : new PlainLocalStorageDriver();

setCacheConfigurations({ driver });

Server-rendered pages see an empty runtime cache (each request creates fresh state if you construct per-request), then the client takes over with its own driver on the next render.

has() semantics

has(missingKey) resolves to false. RunTimeDriver.getItem returns null (not undefined) for misses, matching the Web Storage API contract that BaseCacheEngine.has() relies on (getItem(...) !== null), and has() performs the same expiry check as get() so the two agree on a live-vs-expired entry. Coverage lives at src/__tests__/runtime-driver.test.ts.