refactor: optimize user fetching in MemoCommentMessage and MemoReactionListView components

web/src/components/Inbox/MemoCommentMessage.tsx

@@ -8,10 +8,11 @@ import { activityServiceClient, memoServiceClient, userServiceClient } from "@/c
 import { activityNamePrefix } from "@/helpers/resource-names";
 import useAsyncEffect from "@/hooks/useAsyncEffect";
 import useNavigateTo from "@/hooks/useNavigateTo";
+import { useUser } from "@/hooks/useUserQueries";
 import { handleError } from "@/lib/error";
 import { cn } from "@/lib/utils";
 import { Memo } from "@/types/proto/api/v1/memo_service_pb";
-import { User, UserNotification, UserNotification_Status } from "@/types/proto/api/v1/user_service_pb";
+import { UserNotification, UserNotification_Status } from "@/types/proto/api/v1/user_service_pb";
 import { useTranslate } from "@/utils/i18n";
 
 interface Props {
@@ -23,10 +24,12 @@ function MemoCommentMessage({ notification }: Props) {
   const navigateTo = useNavigateTo();
   const [relatedMemo, setRelatedMemo] = useState<Memo | undefined>(undefined);
   const [commentMemo, setCommentMemo] = useState<Memo | undefined>(undefined);
-  const [sender, setSender] = useState<User | undefined>(undefined);
+  const [senderName, setSenderName] = useState<string | undefined>(undefined);
   const [initialized, setInitialized] = useState<boolean>(false);
   const [hasError, setHasError] = useState<boolean>(false);
 
+  const { data: sender } = useUser(senderName || "", { enabled: !!senderName });
+
   useAsyncEffect(async () => {
     if (!notification.activityId) {
       return;
@@ -44,16 +47,12 @@ function MemoCommentMessage({ notification }: Props) {
         });
         setRelatedMemo(memo);
 
-        // Fetch the comment memo
         const comment = await memoServiceClient.getMemo({
           name: memoCommentPayload.memo,
         });
         setCommentMemo(comment);
 
-        const sender = await userServiceClient.getUser({
-          name: notification.sender,
-        });
-        setSender(sender);
+        setSenderName(notification.sender);
         setInitialized(true);
       }
     } catch (error) {

web/src/components/MemoReactionListView/hooks.ts

@@ -1,33 +1,30 @@
 import { useQueryClient } from "@tanstack/react-query";
-import { uniq } from "lodash-es";
-import { useEffect, useState } from "react";
-import { memoServiceClient, userServiceClient } from "@/connect";
+import { useMemo } from "react";
+import { memoServiceClient } from "@/connect";
 import useCurrentUser from "@/hooks/useCurrentUser";
 import { memoKeys } from "@/hooks/useMemoQueries";
+import { useUsersByNames } from "@/hooks/useUserQueries";
 import type { Memo, Reaction } from "@/types/proto/api/v1/memo_service_pb";
 import type { User } from "@/types/proto/api/v1/user_service_pb";
 
 export type ReactionGroup = Map<string, User[]>;
 
 export const useReactionGroups = (reactions: Reaction[]): ReactionGroup => {
-  const [reactionGroup, setReactionGroup] = useState<ReactionGroup>(new Map());
+  const creatorNames = useMemo(() => reactions.map((r) => r.creator), [reactions]);
+  const { data: userMap } = useUsersByNames(creatorNames);
 
-  useEffect(() => {
-    const fetchReactionGroups = async () => {
-      const newReactionGroup = new Map<string, User[]>();
-      for (const reaction of reactions) {
-        // Fetch user via gRPC directly since we need it within an effect
-        const user = await userServiceClient.getUser({ name: reaction.creator });
-        const users = newReactionGroup.get(reaction.reactionType) || [];
-        users.push(user);
-        newReactionGroup.set(reaction.reactionType, uniq(users));
-      }
-      setReactionGroup(newReactionGroup);
-    };
-    fetchReactionGroups();
-  }, [reactions]);
+  return useMemo(() => {
+    const reactionGroup = new Map<string, User[]>();
+    for (const reaction of reactions) {
+      const user = userMap?.get(reaction.creator);
+      if (!user) continue;
 
-  return reactionGroup;
+      const users = reactionGroup.get(reaction.reactionType) || [];
+      users.push(user);
+      reactionGroup.set(reaction.reactionType, users);
+    }
+    return reactionGroup;
+  }, [reactions, userMap]);
 };
 
 interface UseReactionActionsOptions {

web/src/components/PagedMemoList/PagedMemoList.tsx

@@ -1,4 +1,5 @@
-import { ArrowUpIcon, LoaderIcon } from "lucide-react";
+import { useQueryClient } from "@tanstack/react-query";
+import { ArrowUpIcon } from "lucide-react";
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import { matchPath } from "react-router-dom";
 import { Button } from "@/components/ui/button";
@@ -6,6 +7,7 @@ import { userServiceClient } from "@/connect";
 import { useView } from "@/contexts/ViewContext";
 import { DEFAULT_LIST_MEMOS_PAGE_SIZE } from "@/helpers/consts";
 import { useInfiniteMemos } from "@/hooks/useMemoQueries";
+import { userKeys } from "@/hooks/useUserQueries";
 import { Routes } from "@/router";
 import { State } from "@/types/proto/api/v1/common_pb";
 import type { Memo } from "@/types/proto/api/v1/memo_service_pb";
@@ -81,6 +83,7 @@ function useAutoFetchWhenNotScrollable({
 const PagedMemoList = (props: Props) => {
   const t = useTranslate();
   const { layout } = useView();
+  const queryClient = useQueryClient();
 
   // Show memo editor only on the root route
   const showMemoEditor = Boolean(matchPath(Routes.ROOT, window.location.pathname));
@@ -99,7 +102,7 @@ const PagedMemoList = (props: Props) => {
   // Apply custom sorting if provided, otherwise use memos directly
   const sortedMemoList = useMemo(() => (props.listSort ? props.listSort(memos) : memos), [memos, props.listSort]);
 
-  // Batch-fetch creators when new data arrives to improve performance
+  // Prefetch creators when new data arrives to improve performance
   useEffect(() => {
     if (!data?.pages || !props.showCreator) return;
 
@@ -107,14 +110,17 @@ const PagedMemoList = (props: Props) => {
     if (!lastPage?.memos) return;
 
     const uniqueCreators = Array.from(new Set(lastPage.memos.map((memo) => memo.creator)));
-    void Promise.allSettled(
-      uniqueCreators.map((creator) =>
-        userServiceClient.getUser({ name: creator }).catch(() => {
-          /* silently ignore errors */
-        }),
-      ),
-    );
-  }, [data?.pages, props.showCreator]);
+    for (const creator of uniqueCreators) {
+      void queryClient.prefetchQuery({
+        queryKey: userKeys.detail(creator),
+        queryFn: async () => {
+          const user = await userServiceClient.getUser({ name: creator });
+          return user;
+        },
+        staleTime: 1000 * 60 * 5,
+      });
+    }
+  }, [data?.pages, props.showCreator, queryClient]);
 
   // Auto-fetch hook: fetches more content when page isn't scrollable
   useAutoFetchWhenNotScrollable({

web/src/hooks/useUserQueries.ts

@@ -15,6 +15,7 @@ export const userKeys = {
   currentUser: () => [...userKeys.all, "current"] as const,
   shortcuts: () => [...userKeys.all, "shortcuts"] as const,
   notifications: () => [...userKeys.all, "notifications"] as const,
+  byNames: (names: string[]) => [...userKeys.all, "byNames", ...names.sort()] as const,
 };
 
 // NOTE: This hook is currently UNUSED in favor of the AuthContext-based
@@ -226,3 +227,33 @@ export function useUpdateUserGeneralSetting(currentUserName?: string) {
     },
   });
 }
+
+// Hook to fetch multiple users by names (returns Map<name, User>)
+export function useUsersByNames(names: string[]) {
+  const enabled = names.length > 0;
+  const uniqueNames = Array.from(new Set(names));
+
+  return useQuery({
+    queryKey: userKeys.byNames(uniqueNames),
+    queryFn: async () => {
+      const users = await Promise.all(
+        uniqueNames.map(async (name) => {
+          try {
+            const user = await userServiceClient.getUser({ name });
+            return { name, user };
+          } catch {
+            return { name, user: undefined };
+          }
+        }),
+      );
+
+      const userMap = new Map<string, User | undefined>();
+      for (const { name, user } of users) {
+        userMap.set(name, user);
+      }
+      return userMap;
+    },
+    enabled,
+    staleTime: 1000 * 60 * 5, // 5 minutes - user profiles don't change often
+  });
+}