From a19b1e83a9a7e9ee426813cbcb8f11e4c3d892d0 Mon Sep 17 00:00:00 2001
From: Alex Gleason <alex@alexgleason.me>
Date: Mon, 13 Mar 2023 16:39:23 -0500
Subject: [PATCH] EntityStore: parse entities after fetch, not during render
 (performance)

---
 app/soapbox/entity-store/hooks/useEntities.ts | 12 +++++++-----
 app/soapbox/entity-store/hooks/useEntity.ts   |  9 +++------
 2 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/app/soapbox/entity-store/hooks/useEntities.ts b/app/soapbox/entity-store/hooks/useEntities.ts
index fa7e26d626..72cec62f52 100644
--- a/app/soapbox/entity-store/hooks/useEntities.ts
+++ b/app/soapbox/entity-store/hooks/useEntities.ts
@@ -3,6 +3,7 @@ import z from 'zod';
 
 import { getNextLink, getPrevLink } from 'soapbox/api';
 import { useApi, useAppDispatch, useAppSelector } from 'soapbox/hooks';
+import { filteredArray } from 'soapbox/schemas/utils';
 
 import { entitiesFetchFail, entitiesFetchRequest, entitiesFetchSuccess } from '../actions';
 
@@ -52,10 +53,9 @@ function useEntities<TEntity extends Entity>(
 
   const entities: readonly TEntity[] = entityIds ? (
     Array.from(entityIds).reduce<TEntity[]>((result, id) => {
-      // TODO: parse after fetch, not during render.
-      const entity = schema.safeParse(cache?.store[id]);
-      if (entity.success) {
-        result.push(entity.data);
+      const entity = cache?.store[id];
+      if (entity) {
+        result.push(entity as TEntity);
       }
       return result;
     }, [])
@@ -74,7 +74,9 @@ function useEntities<TEntity extends Entity>(
     dispatch(entitiesFetchRequest(entityType, listKey));
     try {
       const response = await api.get(url);
-      dispatch(entitiesFetchSuccess(response.data, entityType, listKey, {
+      const entities = filteredArray(schema).parse(response.data);
+
+      dispatch(entitiesFetchSuccess(entities, entityType, listKey, {
         next: getNextLink(response),
         prev: getPrevLink(response),
         fetching: false,
diff --git a/app/soapbox/entity-store/hooks/useEntity.ts b/app/soapbox/entity-store/hooks/useEntity.ts
index d242c9b4ef..92f20560ec 100644
--- a/app/soapbox/entity-store/hooks/useEntity.ts
+++ b/app/soapbox/entity-store/hooks/useEntity.ts
@@ -30,11 +30,7 @@ function useEntity<TEntity extends Entity>(
   const defaultSchema = z.custom<TEntity>();
   const schema = opts.schema || defaultSchema;
 
-  const entity = useAppSelector(state => {
-    // TODO: parse after fetch, not during render.
-    const result = schema.safeParse(state.entities[entityType]?.store[entityId]);
-    return result.success ? result.data : undefined;
-  });
+  const entity = useAppSelector(state => state.entities[entityType]?.store[entityId] as TEntity | undefined);
 
   const [isFetching, setIsFetching] = useState(false);
   const isLoading = isFetching && !entity;
@@ -42,7 +38,8 @@ function useEntity<TEntity extends Entity>(
   const fetchEntity = () => {
     setIsFetching(true);
     api.get(endpoint).then(({ data }) => {
-      dispatch(importEntities([data], entityType));
+      const entity = schema.parse(data);
+      dispatch(importEntities([entity], entityType));
       setIsFetching(false);
     }).catch(() => {
       setIsFetching(false);