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#AtomCookiePersistence

#Import

typescript 
1import { AtomCookiePersistence } from "alepha/server/cookies";

#Overview

Binds every atom declared with persist: "cookie" to an HTTP cookie.

  • server:onRequest — seeds the request-scoped state from the cookie, so SSR renders with the persisted value.
  • state:mutate — writes the new value back as a Set-Cookie header.
  • state:register — an atom registering lazily during a request (first touched by an SSR render, after server:onRequest already ran) reads its cookie right away, so that render still sees the persisted value.

Atoms are resolved from the StateManager registry (alepha.store.listAtoms()) on every request and every mutation, never from a map built up from state:register events. That event fires exactly once per atom and is never replayed, while $module.register() registers atoms[] BEFORE it wires imports[] and injects services[] — so the documented $module({ atoms, imports: [AlephaServerCookies], services }) shape registers every atom before this provider exists. An event-sourced map would stay empty forever there, making persist: "cookie" a silent no-op in both directions. Reading the registry on demand is order-independent.

The cookie is named after the atom key, lives 365 days, SameSite=lax, path "/". For custom cookie options (encryption, signing, custom TTL), declare an explicit $cookie({ key: atom.key, ... }) binding instead.