# $cache

## Import

```typescript
import { $cache } from "alepha/cache";
```

## Overview

Creates a cache primitive for caching with automatic management.

**Middleware mode** (no `handler`) - usable in `use` arrays AND as a store:

```ts
class UserService {
  userCache = $cache({ name: "users", ttl: [10, "minutes"] });

  fetchUser = $pipeline({
    use: [this.userCache],
    handler: async (userId: string) => this.repo.getById(userId),
  });

  async invalidateUser(userId: string) {
    await this.userCache.invalidate(userId);
  }
}
```

**Primitive mode** (with `handler`) - standalone callable:

```ts
getUserData = $cache({
  name: "user-data",
  ttl: [10, "minutes"],
  handler: async (userId: string) => {
    return await database.users.findById(userId);
  },
});
```

## Options

| Option     | Type                                       | Required | Description                                              |
| ---------- | ------------------------------------------ | -------- | -------------------------------------------------------- |
| `name`     | `string`                                   | No       | The cache name                                           |
| `handler`  | `Object`                                   | No       | Function which returns cached data.                      |
| `key`      | `Object`                                   | No       | The key generator for the cache                          |
| `provider` | `Service<CacheProvider> \| "memory"` | No       | The store provider for the cache                         |
| `ttl`      | `DurationLike`                             | No       | The time-to-live for the cache, as a `DurationLike` (e.g |
| `disabled` | `boolean`                                  | No       | If the cache is disabled.                                |
| `compress` | `boolean`                                  | No       | Enable gzip compression for cached values                |
| `memory`   | `true \| CacheMemoryTierOptions`           | No       | Add an in-process L1 memory tier in front of `provider`  |
| `stale`    | `DurationLike`                             | No       | Stale-while-revalidate window                            |