feat: query save/restore

packages/system/package.json

@@ -41,6 +41,7 @@
     "eventemitter3": "^5.0.1",
     "isomorphic-ws": "^5.0.0",
     "lokijs": "^1.5.12",
+    "lru-cache": "^10.2.0",
     "uuid": "^9.0.0",
     "ws": "^8.14.0"
   }

packages/system/src/connection.ts

@@ -386,7 +386,7 @@ export class Connection extends EventEmitter<ConnectionEvents> {
             const latest = eventSet.reduce((acc, v) => (acc = v.created_at > acc ? v.created_at : acc), 0);
             const newFilters = filters.map(a => ({
               ...a,
-              since: latest,
+              since: latest + 1,
             }));
             this.queueReq(["REQ", id, ...newFilters], item.cb);
           }

packages/system/src/query-manager.ts

@@ -166,13 +166,6 @@ export class QueryManager extends EventEmitter<QueryManagerEvents> {
     }
   }
 
-  /**
-   * Split request into 2 branches.
-   * 1. Request cache for results
-   * 2. Send query to relays
-   */
-  #splitSyncRequest(req: BuiltRawReqFilter) {}
-
   #cleanup() {
     let changed = false;
     for (const [k, v] of this.#queries) {

packages/system/src/query.ts

@@ -3,10 +3,11 @@ import debug from "debug";
 import EventEmitter from "eventemitter3";
 import { unixNowMs, unwrap } from "@snort/shared";
 
-import { Connection, ReqFilter, Nips, TaggedNostrEvent, SystemInterface } from ".";
+import { Connection, ReqFilter, Nips, TaggedNostrEvent, SystemInterface, ParsedFragment } from ".";
 import { NoteCollection } from "./note-collection";
 import { BuiltRawReqFilter, RequestBuilder } from "./request-builder";
 import { eventMatchesFilter } from "./request-matcher";
+import { LRUCache } from "lru-cache";
 
 interface QueryTraceEvents {
   change: () => void;
@@ -105,6 +106,11 @@ export interface QueryEvents {
   end: () => void;
 }
 
+const QueryCache = new LRUCache<string, Array<TaggedNostrEvent>>({
+  ttl: 60_000 * 3,
+  ttlAutopurge: true,
+});
+
 /**
  * Active or queued query on the system
  */
@@ -175,6 +181,11 @@ export class Query extends EventEmitter<QueryEvents> {
     this.#groupingDelay = req.options?.groupingDelay ?? 100;
     this.#checkTraces();
 
+    const cached = QueryCache.get(this.request.id);
+    if (cached) {
+      this.#log("Restored %o for %s", cached, this.request.id);
+      this.feed.add(cached);
+    }
     this.feed.on("event", evs => this.emit("event", evs));
     this.#start();
   }
@@ -234,7 +245,7 @@ export class Query extends EventEmitter<QueryEvents> {
    * This function should be called when this Query object and FeedStore is no longer needed
    */
   cancel() {
-    this.#cancelAt = unixNowMs() + 5_000;
+    this.#cancelAt = unixNowMs() + 1_000;
   }
 
   uncancel() {
@@ -248,6 +259,8 @@ export class Query extends EventEmitter<QueryEvents> {
     }
     this.#stopCheckTraces();
     this.emit("end");
+    QueryCache.set(this.request.id, this.feed.snapshot);
+    this.#log("Saved %O for %s", this.feed.snapshot, this.request.id);
   }
 
   /**

yarn.lock

@@ -3091,6 +3091,7 @@ __metadata:
     jest: ^29.5.0
     jest-environment-jsdom: ^29.5.0
     lokijs: ^1.5.12
+    lru-cache: ^10.2.0
     ts-jest: ^29.1.0
     ts-node: ^10.9.1
     typescript: ^5.2.2
@@ -8280,6 +8281,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"lru-cache@npm:^10.2.0":
+  version: 10.2.0
+  resolution: "lru-cache@npm:10.2.0"
+  checksum: eee7ddda4a7475deac51ac81d7dd78709095c6fa46e8350dc2d22462559a1faa3b81ed931d5464b13d48cbd7e08b46100b6f768c76833912bc444b99c37e25db
+  languageName: node
+  linkType: hard
+
 "lru-cache@npm:^5.1.1":
   version: 5.1.1
   resolution: "lru-cache@npm:5.1.1"