address comments

packages/core/src/lib/waku_store/index.ts

@@ -4,7 +4,13 @@ import type { PeerId } from "@libp2p/interface-peer-id";
 import type { Peer, PeerStore } from "@libp2p/interface-peer-store";
 import { sha256 } from "@noble/hashes/sha256";
 import { concat, utf8ToBytes } from "@waku/byte-utils";
-import { DecodedMessage, Decoder, Index, Store } from "@waku/interfaces";
+import {
+  Cursor,
+  DecodedMessage,
+  Decoder,
+  Index,
+  Store,
+} from "@waku/interfaces";
 import debug from "debug";
 import all from "it-all";
 import * as lp from "it-length-prefixed";
@@ -84,8 +90,10 @@ export interface QueryOptions {
   timeFilter?: TimeFilter;
   /**
    * Cursor as an index to start a query from.
+   * The cursor index will be exclusive (i.e. the message at the cursor index will not be included in the result).
+   * If undefined, the query will start from the beginning or end of the history, depending on the page direction.
    */
-  cursor?: Index;
+  cursor?: Cursor;
 }
 
 /**
@@ -289,7 +297,7 @@ async function* paginate<T extends DecodedMessage>(
   protocol: string,
   queryOpts: Params,
   decoders: Map<string, Decoder<T>>,
-  cursor?: Index
+  cursor?: Cursor
 ): AsyncGenerator<Promise<T | undefined>[]> {
   if (
     queryOpts.contentTopics.toString() !==
@@ -300,8 +308,10 @@ async function* paginate<T extends DecodedMessage>(
     );
   }
 
+  let currentCursor = cursor;
+
   while (true) {
-    queryOpts = Object.assign(queryOpts, { cursor });
+    queryOpts = Object.assign(queryOpts, { currentCursor });
 
     const stream = await connection.newStream(protocol);
     const historyRpcQuery = HistoryRPC.createQuery(queryOpts);
@@ -362,8 +372,8 @@ async function* paginate<T extends DecodedMessage>(
       return Promise.resolve(undefined);
     });
 
-    cursor = response.pagingInfo?.cursor;
-    if (typeof cursor === "undefined") {
+    const nextCursor = response.pagingInfo?.cursor;
+    if (typeof nextCursor === "undefined") {
       // If the server does not return cursor then there is an issue,
       // Need to abort, or we end up in an infinite loop
       log(
@@ -372,6 +382,8 @@ async function* paginate<T extends DecodedMessage>(
       break;
     }
 
+    currentCursor = nextCursor;
+
     const responsePageSize = response.pagingInfo?.pageSize;
     const queryPageSize = historyRpcQuery.query?.pagingInfo?.pageSize;
     if (

packages/interfaces/src/index.ts

@@ -60,6 +60,12 @@ export interface TimeFilter {
   endTime: Date;
 }
 
+export type Cursor = {
+  digest?: Uint8Array;
+  senderTime?: bigint;
+  pubsubTopic?: string;
+};
+
 export type StoreQueryOptions = {
   /**
    * The direction in which pages are retrieved:
@@ -83,7 +89,7 @@ export type StoreQueryOptions = {
   /**
    * Cursor as an index to start a query from.
    */
-  cursor?: Index;
+  cursor?: Cursor;
 } & ProtocolOptions;
 
 export interface Store extends PointToPointProtocol {