use InMemoryDB instead of seenEvents LRUSet

packages/app/src/Cache/InMemoryDB.ts

@@ -0,0 +1,214 @@
+import { ID, ReqFilter as Filter, STR, TaggedNostrEvent, UID } from "@snort/system";
+import loki from "lokijs";
+
+type PackedNostrEvent = {
+  id: UID;
+  pubkey: number;
+  kind: number;
+  tags: Array<string | UID>[];
+  flatTags: string[];
+  sig: string;
+  created_at: number;
+  content?: string;
+  relays: string[];
+  saved_at: number;
+};
+
+const DEFAULT_MAX_SIZE = 10000;
+
+class InMemoryDB {
+  private loki = new loki("EventDB");
+  private eventsCollection: Collection<PackedNostrEvent>;
+  private maxSize: number;
+
+  constructor(maxSize = DEFAULT_MAX_SIZE) {
+    this.maxSize = maxSize;
+    this.eventsCollection = this.loki.addCollection("events", {
+      unique: ["id"],
+      indices: ["pubkey", "kind", "flatTags", "created_at", "saved_at"],
+    });
+    this.startRemoveOldestInterval();
+  }
+
+  private startRemoveOldestInterval() {
+    const removeOldest = () => {
+      this.removeOldest();
+      setTimeout(() => removeOldest(), 3000);
+    };
+    setTimeout(() => removeOldest(), 3000);
+  }
+
+  get(id: string): TaggedNostrEvent | undefined {
+    const event = this.eventsCollection.by("id", ID(id)); // throw if db not ready yet?
+    if (event) {
+      return this.unpack(event);
+    }
+  }
+
+  has(id: string): boolean {
+    return !!this.eventsCollection.by("id", ID(id));
+  }
+
+  // map to internal UIDs to save memory
+  private pack(event: TaggedNostrEvent): PackedNostrEvent {
+    return {
+      id: ID(event.id),
+      pubkey: ID(event.pubkey),
+      sig: event.sig,
+      kind: event.kind,
+      tags: event.tags.map(tag => {
+        if (["e", "p"].includes(tag[0]) && typeof tag[1] === "string") {
+          return [tag[0], ID(tag[1] as string), ...tag.slice(2)];
+        } else {
+          return tag;
+        }
+      }),
+      flatTags: event.tags.filter(tag => ["e", "p", "d"].includes(tag[0])).map(tag => `${tag[0]}_${ID(tag[1])}`),
+      created_at: event.created_at,
+      content: event.content,
+      relays: event.relays,
+      saved_at: Date.now(),
+    };
+  }
+
+  private unpack(packedEvent: PackedNostrEvent): TaggedNostrEvent {
+    return <TaggedNostrEvent>{
+      id: STR(packedEvent.id),
+      pubkey: STR(packedEvent.pubkey),
+      sig: packedEvent.sig,
+      kind: packedEvent.kind,
+      tags: packedEvent.tags.map(tag => {
+        if (["e", "p"].includes(tag[0] as string) && typeof tag[1] === "number") {
+          return [tag[0], STR(tag[1] as number), ...tag.slice(2)];
+        } else {
+          return tag;
+        }
+      }),
+      created_at: packedEvent.created_at,
+      content: packedEvent.content,
+      relays: packedEvent.relays,
+    };
+  }
+
+  handleEvent(event: TaggedNostrEvent): boolean {
+    if (!event || !event.id || !event.created_at) {
+      throw new Error("Invalid event");
+    }
+
+    const id = ID(event.id);
+    if (this.eventsCollection.by("id", id)) {
+      return false; // this prevents updating event.relays?
+    }
+
+    const packed = this.pack(event);
+
+    // we might want to limit the kinds of events we save, e.g. no kind 0, 3 or only 1, 6
+
+    try {
+      this.eventsCollection.insert(packed);
+    } catch (e) {
+      return false;
+    }
+
+    return true;
+  }
+
+  remove(eventId: string): void {
+    const id = ID(eventId);
+    this.eventsCollection.findAndRemove({ id });
+    if (this.idb) {
+      try {
+        this.idb.events.where({ id: eventId }).delete();
+      } catch (e) {
+        console.error(e);
+      }
+    }
+  }
+
+  removeOldest(): void {
+    const count = this.eventsCollection.count();
+    console.log("InMemoryDB: count", count, this.maxSize);
+    if (count > this.maxSize) {
+      console.log("InMemoryDB: removing oldest events", count - this.maxSize);
+      this.eventsCollection
+        .chain()
+        .simplesort("saved_at")
+        .limit(count - this.maxSize)
+        .remove();
+    }
+  }
+
+  find(filter: Filter, callback: (event: TaggedNostrEvent) => void): void {
+    this.findArray(filter).forEach(event => {
+      callback(event);
+    });
+  }
+
+  findArray(filter: Filter): TaggedNostrEvent[] {
+    const query = this.constructQuery(filter);
+
+    const searchRegex = filter.search ? new RegExp(filter.search, "i") : undefined;
+    let chain = this.eventsCollection
+      .chain()
+      .find(query)
+      .where((e: PackedNostrEvent) => {
+        if (searchRegex && !e.content?.match(searchRegex)) {
+          return false;
+        }
+        return true;
+      })
+      .simplesort("created_at", true);
+
+    if (filter.limit) {
+      chain = chain.limit(filter.limit);
+    }
+
+    return chain.data().map(e => this.unpack(e));
+  }
+
+  findAndRemove(filter: Filter) {
+    const query = this.constructQuery(filter);
+    this.eventsCollection.findAndRemove(query);
+  }
+
+  private constructQuery(filter: Filter): LokiQuery<PackedNostrEvent> {
+    const query: LokiQuery<PackedNostrEvent> = {};
+
+    if (filter.ids) {
+      query.id = { $in: filter.ids.map(ID) };
+    } else {
+      if (filter.authors) {
+        query.pubkey = { $in: filter.authors.map(ID) };
+      }
+      if (filter.kinds) {
+        query.kind = { $in: filter.kinds };
+      }
+      if (filter["#e"]) {
+        query.flatTags = { $contains: "e_" + filter["#e"]!.map(ID) };
+      } else if (filter["#p"]) {
+        query.flatTags = { $contains: "p_" + filter["#p"]!.map(ID) };
+      } else if (filter["#d"]) {
+        query.flatTags = { $contains: "d_" + filter["#d"]!.map(ID) };
+      }
+      if (filter.since && filter.until) {
+        query.created_at = { $between: [filter.since, filter.until] };
+      }
+      if (filter.since) {
+        query.created_at = { $gte: filter.since };
+      }
+      if (filter.until) {
+        query.created_at = { $lte: filter.until };
+      }
+    }
+
+    return query;
+  }
+
+  findOne(filter: Filter): TaggedNostrEvent | undefined {
+    return this.findArray(filter)[0];
+  }
+}
+
+export { InMemoryDB };
+
+export default new InMemoryDB();

packages/app/src/Db/IndexedDB.ts

@@ -1,5 +1,5 @@
+import LRUSet from "@snort/shared/src/LRUSet";
 import { ReqFilter as Filter, TaggedNostrEvent } from "@snort/system";
-import { seenEvents } from "@snort/system";
 import * as Comlink from "comlink";
 import Dexie, { Table } from "dexie";
 
@@ -23,6 +23,7 @@ class IndexedDB extends Dexie {
   private subscribedAuthorsAndKinds = new Set<string>();
   private readQueue: Map<string, Task> = new Map();
   private isProcessingQueue = false;
+  private seenEvents = new LRUSet(2000);
 
   constructor() {
     super("EventDB");
@@ -61,10 +62,10 @@ class IndexedDB extends Dexie {
   }
 
   handleEvent(event: TaggedNostrEvent) {
-    if (seenEvents.has(event.id)) {
+    if (this.seenEvents.has(event.id)) {
       return;
     }
-    seenEvents.add(event.id);
+    this.seenEvents.add(event.id);
 
     // maybe we don't want event.kind 3 tags
     const tags =
@@ -166,7 +167,7 @@ class IndexedDB extends Dexie {
 
     // make sure only 1 argument is passed
     const cb = e => {
-      seenEvents.add(e.id);
+      this.seenEvents.add(e.id);
       callback(e);
     };
 

packages/app/src/system.ts

@@ -15,6 +15,7 @@ import { addEventToFuzzySearch } from "@/Db/FuzzySearch";
 import IndexedDBWorker from "@/Db/IndexedDB?worker";
 import { LoginStore } from "@/Utils/Login";
 import { hasWasm, WasmOptimizer } from "@/Utils/wasm";
+import inMemoryDB from "@/Cache/InMemoryDB"; // move to system or pass alreadyHave fn to system?
 
 export const indexedDB = Comlink.wrap(new IndexedDBWorker());
 /**
@@ -37,6 +38,7 @@ System.on("auth", async (c, r, cb) => {
 });
 
 System.on("event", (_, ev) => {
+  inMemoryDB.handleEvent(ev);
   addEventToFuzzySearch(ev);
   socialGraphInstance.handleEvent(ev);
   if (CONFIG.useIndexedDBEvents && socialGraphInstance.getFollowDistance(ev.pubkey) <= 2) {
@@ -44,21 +46,24 @@ System.on("event", (_, ev) => {
   }
 });
 
+System.on("request", (filter: ReqFilter) => {
+  inMemoryDB.find(filter, e => System.HandleEvent(e));
+  if (CONFIG.useIndexedDBEvents) {
+    indexedDB.find(
+      filter,
+      Comlink.proxy((e: TaggedNostrEvent) => {
+        System.HandleEvent(e);
+      }),
+    );
+  }
+});
+
 if (CONFIG.useIndexedDBEvents) {
   // load all profiles
   indexedDB.find(
     { kinds: [0] },
     Comlink.proxy((e: TaggedNostrEvent) => System.HandleEvent(e)),
   );
-
-  System.on("request", (filter: ReqFilter) => {
-    indexedDB.find(
-      filter,
-      Comlink.proxy((e: TaggedNostrEvent) => {
-        System.HandleEvent(e);
-      }),
-    );
-  });
 }
 
 /**

packages/system/src/connection.ts

@@ -9,8 +9,8 @@ import { ConnectionStats } from "./connection-stats";
 import { NostrEvent, ReqCommand, ReqFilter, TaggedNostrEvent, u256 } from "./nostr";
 import { RelayInfo } from "./relay-info";
 import EventKind from "./event-kind";
-import { seenEvents } from "./seen-events";
 import { getHex64 } from "./utils";
+import inMemoryDB from "@snort/app/src/Cache/InMemoryDB";
 
 /**
  * Relay settings
@@ -203,12 +203,10 @@ export class Connection extends EventEmitter<ConnectionEvents> {
     if ((e.data as string).length > 0) {
       // skip message processing if we've already seen it
       const msgId = getHex64(e.data as string, "id");
-      /* Disabled in absence of local db
-      if (seenEvents.has(msgId)) {
+      if (inMemoryDB.has(msgId)) {
+        console.log('already have');
         return;
       }
-       */
-      seenEvents.add(msgId); // TODO only do after msg validation
 
       const msg = JSON.parse(e.data as string) as Array<string | NostrEvent | boolean>;
       const tag = msg[0] as string;

packages/system/src/index.ts

@@ -33,7 +33,6 @@ export * from "./query-optimizer";
 export * from "./encrypted";
 export * from "./outbox-model";
 export { parseIMeta } from "./utils";
-export * from "./seen-events";
 
 export * from "./impl/nip4";
 export * from "./impl/nip44";

packages/system/src/seen-events.ts

@@ -1,3 +0,0 @@
-import LRUSet from "@snort/shared/src/LRUSet";
-
-export const seenEvents = new LRUSet<string>(2000);