Persisted observable returns undefined during initial render

[jabahere]

Hello,
Your library looks awesome! I'm trying it out to see if I could use it within my app, and I'm running into a tiny "issue".

When I use observable within my component:

const Component: React.FC<{ children: React.ReactNode }> = ({ children }) => {
  const test$$ = use$(test$);
  
  console.log({ test: test$ })
  
  return (...)
}

I get test$ is undefined during the initial render (app launch).
I'd like to avoid getting undefined on initial render if possible. is that possible to achieve?

This is how my test$ observable is defined:

export const supabase = createClient<Database>(supabaseUrl, supabaseAnonKey);

const customSynced = configureSynced(syncedSupabase, {
  persist: {
    plugin: observablePersistAsyncStorage({
      AsyncStorage,
    }),
  },
  generateId: randomUUID,
  supabase,
  changesSince: "last-sync",
  fieldCreatedAt: "created_at",
  fieldUpdatedAt: "updated_at",
  fieldDeleted: "deleted",
});

export const test$ = observable(
  customSynced({
    supabase,
    collection: "test",
    select: (from) => from.select("*"),
    actions: ["read", "create", "update", "delete"],
    realtime: true,
    persist: {
      name: "test",
      retrySync: true,
    },
    retry: {
      infinite: true,
    },
  }),
);

I'm assuming this is happening because I'm using AsyncStorage as my persistence layer?
I'm using "@legendapp/state": "^3.0.0-beta.24", within react-native project.

Thanks!

[jmeistrich]

Yes, it's because AsyncStorage is async. If you want a synchronous persistence you could use the MMKV plugin or the new kv-store plugin which is in the latest version but not yet documented. Details are here: #444

[jabahere]

Thanks @jmeistrich, new expo-sqlite kv store works great, thought there's a misleading error which I ended up fixing in my fork. Here's PR if you're open to contributions: https://github.com/LegendApp/legend-state/pull/449/files

[jmeistrich]

Oh thanks, not sure how that mistake got through there!

[jmeistrich]

Just released beta.26 with your PR, thank you!