## @snort/system

A collection of caching and querying techniquies used by https://snort.social to serve all content from the nostr protocol.

Simple example:
```js
import { 
    NostrSystem, 
    EventPublisher, 
    UserRelaysCache, 
    RequestBuilder, 
    FlatNoteStore, 
    StoreSnapshot 
} from "@snort/system"

// Provided in-memory / indexedDb cache for relays
// You can also implement your own with "RelayCache" interface
const RelaysCache = new UserRelaysCache();

// example auth handler using NIP-07
const AuthHandler = async (challenge: string, relay: string) => {
    const pub = await EventPublisher.nip7();
    if (pub) {
        return await pub.nip42Auth(challenge, relay);
    }
}

// Singleton instance to store all connections and access query fetching system
const System = new NostrSystem({
    relayCache: RelaysCache,
    authHandler: AuthHandler // can be left undefined if you dont care about NIP-42 Auth
});

(async () => {
    // connec to one "bootstrap" relay to pull profiles/relay lists from
    // also used as a fallback relay when gossip model doesnt know which relays to pick, or "authors" are not provided in the request
    await System.ConnectToRelay("wss://relay.snort.social", { read: true, write: false });

    // ID should be unique to the use case, this is important as all data fetched from this ID will be merged into the same NoteStore
    const rb = new RequestBuilder("get-posts");
    rb.withFilter()
        .authors(["63fe6318dc58583cfe16810f86dd09e18bfd76aabc24a0081ce2856f330504ed"]) // Kieran pubkey
        .kinds([1])
        .limit(10);

    const q = System.Query<FlatNoteStore>(FlatNoteStore, rb);
    // basic usage using "onEvent", fired for every event added to the store
    q.onEvent = (sub, e) => {
        console.debug(sub, e);
    }

    // Hookable type using change notification, limited to every 500ms
    const release = q.feed.hook(() => {
        // since we use the FlatNoteStore we expect NostrEvent[]
        // other stores provide different data, like a single event instead of an array (latest version)
        const state = q.feed.snapshot as StoreSnapshot<ReturnType<FlatNoteStore["getSnapshotData"]>>;

        // do something with snapshot of store
        console.log(`We have ${state.data.length} events now!`)
    });

    // release the hook when its not needed anymore
    // these patterns will be managed in @snort/system-react to make it easier to use react or other UI frameworks
    // release();
})();
```