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React Query์™€ ํ•จ๊ป˜ ์‚ฌ์šฉํ•˜๊ธฐ

โ€œํ‚ค๋ฅผ ์–ด๋””์— ๋‘์–ด์•ผ ํ•˜๋Š”๊ฐ€โ€ ๋ฌธ์ œโ€‹

ํ•ด๊ฒฐ์ฑ… โ€” ์—”ํ‹ฐํ‹ฐ๋ณ„๋กœ ๋ถ„๋ฆฌํ•˜๊ธฐโ€‹

ํ”„๋กœ์ ํŠธ๊ฐ€ ์ด๋ฏธ ์—”ํ‹ฐํ‹ฐ ๋‹จ์œ„๋กœ ๊ตฌ์„ฑ๋˜์–ด ์žˆ์œผ๋ฉฐ, ๊ฐ ์š”์ฒญ์ด ๋‹จ์ผ ์—”ํ‹ฐํ‹ฐ์— ํ•ด๋‹นํ•œ๋‹ค๋ฉด, ์—”ํ‹ฐํ‹ฐ๋ณ„๋กœ ์ฝ”๋“œ๋ฅผ ๊ตฌ์„ฑํ•˜๋Š” ๊ฒƒ์ด ์ข‹์Šต๋‹ˆ๋‹ค. ์˜ˆ๋ฅผ ๋“ค์–ด, ๋‹ค์Œ๊ณผ ๊ฐ™์€ ๋””๋ ‰ํ† ๋ฆฌ ๊ตฌ์กฐ๋ฅผ ์‚ฌ์šฉํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค:

โ””โ”€โ”€ src/                                        #
โ”œโ”€โ”€ app/ #
| ... #
โ”œโ”€โ”€ pages/ #
| ... #
โ”œโ”€โ”€ entities/ #
| โ”œโ”€โ”€ {entity}/ #
| ... โ””โ”€โ”€ api/ #
| โ”œโ”€โ”€ `{entity}.query` # ์ฟผ๋ฆฌ ํ‚ค์™€ ํ•จ์ˆ˜
| โ”œโ”€โ”€ `get-{entity}` # ์—”ํ‹ฐํ‹ฐ ์กฐํšŒ ํ•จ์ˆ˜
| โ”œโ”€โ”€ `create-{entity}` # ์—”ํ‹ฐํ‹ฐ ์ƒ์„ฑ ํ•จ์ˆ˜
| โ”œโ”€โ”€ `update-{entity}` # ์—”ํ‹ฐํ‹ฐ ์—…๋ฐ์ดํŠธ ํ•จ์ˆ˜
| โ”œโ”€โ”€ `delete-{entity}` # ์—”ํ‹ฐํ‹ฐ ์‚ญ์ œ ํ•จ์ˆ˜
| ... #
| #
โ”œโ”€โ”€ features/ #
| ... #
โ”œโ”€โ”€ widgets/ #
| ... #
โ””โ”€โ”€ shared/ #
... #

๋งŒ์•ฝ ์—”ํ‹ฐํ‹ฐ ๊ฐ„์— ์—ฐ๊ฒฐ์ด ํ•„์š”ํ•œ ๊ฒฝ์šฐ (์˜ˆ: Country ์—”ํ‹ฐํ‹ฐ์— City ์—”ํ‹ฐํ‹ฐ ํ•„๋“œ๊ฐ€ ํฌํ•จ๋˜๋Š” ๊ฒฝ์šฐ), @x-notation์„ ํ™œ์šฉํ•œ ๊ต์ฐจ ์ž„ํฌํŠธ ๋ฐฉ์‹์„ ์‚ฌ์šฉํ•˜๊ฑฐ๋‚˜ ๋Œ€์•ˆ์œผ๋กœ ์•„๋ž˜์˜ ๊ตฌ์กฐ๋ฅผ ๊ณ ๋ คํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค.

๋Œ€์•ˆ ๋ฐฉ์•ˆ โ€” shared์— ์œ ์ง€ํ•˜๊ธฐโ€‹

์—”ํ‹ฐํ‹ฐ๋ณ„ ๋ถ„๋ฆฌ๊ฐ€ ์ ์ ˆํ•˜์ง€ ์•Š์€ ๊ฒฝ์šฐ, ๋‹ค์Œ๊ณผ ๊ฐ™์€ ๊ตฌ์กฐ๋ฅผ ์‚ฌ์šฉํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค:

โ””โ”€โ”€ src/                                        #
... #
โ””โ”€โ”€ shared/ #
โ”œโ”€โ”€ api/ #
... โ”œโ”€โ”€ `queries` # ์ฟผ๋ฆฌ ํŒฉํ† ๋ฆฌ๋“ค
| โ”œโ”€โ”€ `document.ts` #
| โ”œโ”€โ”€ `background-jobs.ts` #
| ... #
โ””โ”€โ”€ index.ts #

์ดํ›„ @/shared/api/index.ts์—์„œ ๋‹ค์Œ๊ณผ ๊ฐ™์ด ์‚ฌ์šฉํ•ฉ๋‹ˆ๋‹ค:

@/shared/api/index.ts
export { documentQueries } from "./queries/document";

"mutation ์œ„์น˜ ์„ค์ •" ๋ฌธ์ œโ€‹

์ฟผ๋ฆฌ์™€ mutation์„ ๊ฐ™์€ ์œ„์น˜์— ๋‘๋Š” ๊ฒƒ์€ ๊ถŒ์žฅ๋˜์ง€ ์•Š์Šต๋‹ˆ๋‹ค. ๋‹ค์Œ ๋‘ ๊ฐ€์ง€ ์˜ต์…˜์ด ์žˆ์Šต๋‹ˆ๋‹ค:

1. ์‚ฌ์šฉ ์œ„์น˜ ๊ทผ์ฒ˜์˜ api ๋””๋ ‰ํ† ๋ฆฌ์—์„œ ์ปค์Šคํ…€ ํ›… ์ •์˜ํ•˜๊ธฐโ€‹

@/features/update-post/api/use-update-title.ts
export const useUpdateTitle = () => {
const queryClient = useQueryClient();

return useMutation({
mutationFn: ({ id, newTitle }) =>
apiClient
.patch(`/posts/${id}`, { title: newTitle })
.then((data) => console.log(data)),

onSuccess: (newPost) => {
queryClient.setQueryData(postsQueries.ids(id), newPost);
},
});
};

2. ๊ณต์šฉ ๋˜๋Š” ์—”ํ‹ฐํ‹ฐ์—์„œ mutation ํ•จ์ˆ˜๋ฅผ ์ •์˜ํ•˜๊ณ , ์ปดํฌ๋„ŒํŠธ์—์„œ useMutation์„ ์ง์ ‘ ์‚ฌ์šฉํ•˜๊ธฐโ€‹

const { mutateAsync, isPending } = useMutation({
mutationFn: postApi.createPost,
});
@/pages/post-create/ui/post-create-page.tsx
export const CreatePost = () => {
const { classes } = useStyles();
const [title, setTitle] = useState("");

const { mutate, isPending } = useMutation({
mutationFn: postApi.createPost,
});

const handleChange = (e: ChangeEvent<HTMLInputElement>) =>
setTitle(e.target.value);
const handleSubmit = (e: FormEvent<HTMLFormElement>) => {
e.preventDefault();
mutate({ title, userId: DEFAULT_USER_ID });
};

return (
<form className={classes.create_form} onSubmit={handleSubmit}>
<TextField onChange={handleChange} value={title} />
<LoadingButton type="submit" variant="contained" loading={isPending}>
Create
</LoadingButton>
</form>
);
};

์š”์ฒญ์˜ ์กฐ์งํ™”โ€‹

์ฟผ๋ฆฌ ํŒฉํ† ๋ฆฌโ€‹

์ฟผ๋ฆฌ ํŒฉํ† ๋ฆฌ๋Š” ์ฟผ๋ฆฌ ํ‚ค ๋ชฉ๋ก์„ ๋ฐ˜ํ™˜ํ•˜๋Š” ํ•จ์ˆ˜๋ฅผ ํฌํ•จํ•œ ๊ฐ์ฒด์ž…๋‹ˆ๋‹ค. ์‚ฌ์šฉ ๋ฐฉ๋ฒ•์€ ๋‹ค์Œ๊ณผ ๊ฐ™์Šต๋‹ˆ๋‹ค:

const keyFactory = {
all: () => ["entity"],
lists: () => [...postQueries.all(), "list"],
};
info

queryOptions๋Š” react-query@v5์˜ ๋‚ด์žฅ ์œ ํ‹ธ๋ฆฌํ‹ฐ์ž…๋‹ˆ๋‹ค (์„ ํƒ ์‚ฌํ•ญ)

queryOptions({
queryKey,
...options,
});

๋” ํฐ ํƒ€์ž… ์•ˆ์ •์„ฑ, react-query์˜ ํ–ฅํ›„ ๋ฒ„์ „๊ณผ์˜ ํ˜ธํ™˜์„ฑ, ํ•จ์ˆ˜ ๋ฐ ์ฟผ๋ฆฌ ํ‚ค์— ๋Œ€ํ•œ ์‰ฌ์šด ์•ก์„ธ์Šค๋ฅผ ์œ„ํ•ด, "@tanstack/react-query"์˜ ๋‚ด์žฅ queryOptions ํ•จ์ˆ˜๋ฅผ ์‚ฌ์šฉํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค (์ž์„ธํ•œ ๋‚ด์šฉ์€ ์—ฌ๊ธฐ).

1. ์ฟผ๋ฆฌ ํŒฉํ† ๋ฆฌ ์ƒ์„ฑ ์˜ˆ์‹œโ€‹

@/entities/post/api/post.queries.ts
import { keepPreviousData, queryOptions } from "@tanstack/react-query";
import { getPosts } from "./get-posts";
import { getDetailPost } from "./get-detail-post";
import { PostDetailQuery } from "./query/post.query";

export const postQueries = {
all: () => ["posts"],

lists: () => [...postQueries.all(), "list"],
list: (page: number, limit: number) =>
queryOptions({
queryKey: [...postQueries.lists(), page, limit],
queryFn: () => getPosts(page, limit),
placeholderData: keepPreviousData,
}),

details: () => [...postQueries.all(), "detail"],
detail: (query?: PostDetailQuery) =>
queryOptions({
queryKey: [...postQueries.details(), query?.id],
queryFn: () => getDetailPost({ id: query?.id }),
staleTime: 5000,
}),
};

2. ์• ํ”Œ๋ฆฌ์ผ€์ด์…˜ ์ฝ”๋“œ์—์„œ์˜ ์ฟผ๋ฆฌ ํŒฉํ† ๋ฆฌ ์‚ฌ์šฉ ์˜ˆ์‹œโ€‹

import { useParams } from "react-router-dom";
import { postApi } from "@/entities/post";
import { useQuery } from "@tanstack/react-query";

type Params = {
postId: string;
};

export const PostPage = () => {
const { postId } = useParams<Params>();
const id = parseInt(postId || "");
const {
data: post,
error,
isLoading,
isError,
} = useQuery(postApi.postQueries.detail({ id }));

if (isLoading) {
return <div>Loading...</div>;
}

if (isError || !post) {
return <>{error?.message}</>;
}

return (
<div>
<p>Post id: {post.id}</p>
<div>
<h1>{post.title}</h1>
<div>
<p>{post.body}</p>
</div>
</div>
<div>Owner: {post.userId}</div>
</div>
);
};

์ฟผ๋ฆฌ ํŒฉํ† ๋ฆฌ ์‚ฌ์šฉ์˜ ์žฅ์ โ€‹

  • ์š”์ฒญ ๊ตฌ์กฐํ™”: ํŒฉํ† ๋ฆฌ๋ฅผ ํ†ตํ•ด ๋ชจ๋“  API ์š”์ฒญ์„ ํ•œ ๊ณณ์— ์กฐ์งํ™”ํ•˜์—ฌ ์ฝ”๋“œ์˜ ๊ฐ€๋…์„ฑ๊ณผ ์œ ์ง€๋ณด์ˆ˜์„ฑ์„ ๋†’์ž…๋‹ˆ๋‹ค.
  • ์ฟผ๋ฆฌ ๋ฐ ํ‚ค์— ๋Œ€ํ•œ ํŽธ๋ฆฌํ•œ ์ ‘๊ทผ: ๋‹ค์–‘ํ•œ ์œ ํ˜•์˜ ์ฟผ๋ฆฌ์™€ ํ•ด๋‹น ํ‚ค์— ์‰ฝ๊ฒŒ ์ ‘๊ทผํ•  ์ˆ˜ ์žˆ๋Š” ๋ฉ”์„œ๋“œ๋ฅผ ์ œ๊ณตํ•ฉ๋‹ˆ๋‹ค.
  • ์ฟผ๋ฆฌ ์žฌํ˜ธ์ถœ ์šฉ์ด์„ฑ: ์• ํ”Œ๋ฆฌ์ผ€์ด์…˜์˜ ์—ฌ๋Ÿฌ ๋ถ€๋ถ„์—์„œ ์ฟผ๋ฆฌ ํ‚ค๋ฅผ ๋ณ€๊ฒฝํ•  ํ•„์š” ์—†์ด ์‰ฝ๊ฒŒ ์žฌํ˜ธ์ถœํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค.

ํŽ˜์ด์ง€๋„ค์ด์…˜โ€‹

์ด ์„น์…˜์—์„œ๋Š” ํŽ˜์ด์ง€๋„ค์ด์…˜์„ ์‚ฌ์šฉํ•˜์—ฌ ๊ฒŒ์‹œ๋ฌผ ์—”ํ‹ฐํ‹ฐ๋ฅผ ๊ฐ€์ ธ์˜ค๋Š” API ์š”์ฒญ์„ ์ˆ˜ํ–‰ํ•˜๋Š” getPosts ํ•จ์ˆ˜์˜ ์˜ˆ๋ฅผ ์†Œ๊ฐœํ•ฉ๋‹ˆ๋‹ค.

1. getPosts ํ•จ์ˆ˜ ์ƒ์„ฑํ•˜๊ธฐโ€‹

getPosts ํ•จ์ˆ˜๋Š” api ์„ธ๊ทธ๋จผํŠธ์˜ get-posts.ts ํŒŒ์ผ์— ์žˆ์Šต๋‹ˆ๋‹ค.

@/pages/post-feed/api/get-posts.ts
import { apiClient } from "@/shared/api/base";

import { PostWithPaginationDto } from "./dto/post-with-pagination.dto";
import { PostQuery } from "./query/post.query";
import { mapPost } from "./mapper/map-post";
import { PostWithPagination } from "../model/post-with-pagination";

const calculatePostPage = (totalCount: number, limit: number) =>
Math.floor(totalCount / limit);

export const getPosts = async (
page: number,
limit: number,
): Promise<PostWithPagination> => {
const skip = page * limit;
const query: PostQuery = { skip, limit };
const result = await apiClient.get<PostWithPaginationDto>("/posts", query);

return {
posts: result.posts.map((post) => mapPost(post)),
limit: result.limit,
skip: result.skip,
total: result.total,
totalPages: calculatePostPage(result.total, limit),
};
};

2. ํŽ˜์ด์ง€๋„ค์ด์…˜์„ ์œ„ํ•œ ์ฟผ๋ฆฌ ํŒฉํ† ๋ฆฌโ€‹

postQueries ์ฟผ๋ฆฌ ํŒฉํ† ๋ฆฌ๋Š” ํŠน์ • ํŽ˜์ด์ง€์™€ ์ œํ•œ์— ๋งž์ถฐ ๊ฒŒ์‹œ๋ฌผ ๋ชฉ๋ก์„ ์š”์ฒญํ•˜๋Š” ๋“ฑ ๊ฒŒ์‹œ๋ฌผ ๊ด€๋ จ ๋‹ค์–‘ํ•œ ์ฟผ๋ฆฌ ์˜ต์…˜์„ ์ •์˜ํ•ฉ๋‹ˆ๋‹ค.

import { keepPreviousData, queryOptions } from "@tanstack/react-query";
import { getPosts } from "./get-posts";

export const postQueries = {
all: () => ["posts"],
lists: () => [...postQueries.all(), "list"],
list: (page: number, limit: number) =>
queryOptions({
queryKey: [...postQueries.lists(), page, limit],
queryFn: () => getPosts(page, limit),
placeholderData: keepPreviousData,
}),
};

3. ์• ํ”Œ๋ฆฌ์ผ€์ด์…˜ ์ฝ”๋“œ์—์„œ์˜ ์‚ฌ์šฉโ€‹

@/pages/home/ui/index.tsx
export const HomePage = () => {
const itemsOnScreen = DEFAULT_ITEMS_ON_SCREEN;
const [page, setPage] = usePageParam(DEFAULT_PAGE);
const { data, isFetching, isLoading } = useQuery(
postApi.postQueries.list(page, itemsOnScreen),
);
return (
<>
<Pagination
onChange={(_, page) => setPage(page)}
page={page}
count={data?.totalPages}
variant="outlined"
color="primary"
/>
<Posts posts={data?.posts} />
</>
);
};
note

์˜ˆ์‹œ๋Š” ๋‹จ์ˆœํ™”๋œ ๋ฒ„์ „์ด๋ฉฐ, ์ „์ฒด ์ฝ”๋“œ๋Š” GitHub์—์„œ ํ™•์ธํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค.

์ฟผ๋ฆฌ ๊ด€๋ฆฌ๋ฅผ ์œ„ํ•œ QueryProviderโ€‹

์ด ๊ฐ€์ด๋“œ์—์„œ๋Š” QueryProvider๋ฅผ ์–ด๋–ป๊ฒŒ ๊ตฌ์„ฑํ•˜๋Š”์ง€ ์‚ดํŽด๋ด…๋‹ˆ๋‹ค.

1. QueryProvider ์ƒ์„ฑํ•˜๊ธฐโ€‹

query-provider.tsx ํŒŒ์ผ์€ @/app/providers/query-provider.tsx ๊ฒฝ๋กœ์— ์žˆ์Šต๋‹ˆ๋‹ค.

@/app/providers/query-provider.tsx
import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
import { ReactQueryDevtools } from "@tanstack/react-query-devtools";
import { ReactNode } from "react";

type Props = {
children: ReactNode;
client: QueryClient;
};

export const QueryProvider = ({ client, children }: Props) => {
return (
<QueryClientProvider client={client}>
{children}
<ReactQueryDevtools />
</QueryClientProvider>
);
};

2. QueryClient ์ƒ์„ฑํ•˜๊ธฐโ€‹

QueryClient๋Š” API ์š”์ฒญ์„ ๊ด€๋ฆฌํ•˜๋Š” ์ธ์Šคํ„ด์Šค์ž…๋‹ˆ๋‹ค. query-client.ts ํŒŒ์ผ์€ @/shared/api/query-client.ts์— ์†ํ•ด ์žˆ์œผ๋ฉฐ, ์ฟผ๋ฆฌ ์บ์‹ฑ์„ ์œ„ํ•ด ํŠน์ • ์„ค์ •์œผ๋กœ QueryClient๋ฅผ ์ƒ์„ฑํ•ฉ๋‹ˆ๋‹ค.

@/shared/api/query-client.ts
import { QueryClient } from "@tanstack/react-query";

export const queryClient = new QueryClient({
defaultOptions: {
queries: {
staleTime: 5 * 60 * 1000,
gcTime: 5 * 60 * 1000,
},
},
});

์ฝ”๋“œ ์ƒ์„ฑโ€‹

API ์ฝ”๋“œ๋ฅผ ์ƒ์„ฑํ•ด์ฃผ๋Š” ๋„๊ตฌ๋“ค์ด ์žˆ์ง€๋งŒ, ์ด๋Ÿฌํ•œ ๋ฐฉ์‹์€ ์œ„์˜ ์˜ˆ์ œ ์ฒ˜๋Ÿผ ์ง์ ‘ ์ฝ”๋“œ๋ฅผ ์ž‘์„ฑํ•˜๋Š” ๋ฐฉ๋ฒ•๋ณด๋‹ค ์œ ์—ฐ์„ฑ์ด ๋ถ€์กฑํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค. ๊ทธ๋Ÿฌ๋‚˜ Swagger ํŒŒ์ผ์ด ์ž˜ ๊ตฌ์„ฑ๋˜์–ด ์žˆ๊ณ  ์ด๋Ÿฌํ•œ ์ž๋™ ์ƒ์„ฑ ๋„๊ตฌ๋ฅผ ์‚ฌ์šฉํ•˜๋Š” ๊ฒฝ์šฐ, ์ƒ์„ฑ๋œ ์ฝ”๋“œ๋ฅผ @/shared/api ๋””๋ ‰ํ† ๋ฆฌ์— ๋‘์–ด ๊ด€๋ฆฌํ•˜๋Š” ๊ฒƒ์ด ํšจ์œจ์ ์ผ ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค.

React Query๋ฅผ ์กฐ์งํ™”ํ•˜๊ธฐ ์œ„ํ•œ ์ถ”๊ฐ€ ์กฐ์–ธโ€‹

API ํด๋ผ์ด์–ธํŠธโ€‹

๊ณต์œ  ๋ ˆ์ด์–ด์—์„œ ์ปค์Šคํ…€ API ํด๋ผ์ด์–ธํŠธ ํด๋ž˜์Šค๋ฅผ ์‚ฌ์šฉํ•˜๋ฉด, ํ”„๋กœ์ ํŠธ ๋‚ด API ์ž‘์—…์„ ์ผ๊ด€์„ฑ ์žˆ๊ฒŒ ๊ด€๋ฆฌํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค. ์ด๋ฅผ ํ†ตํ•ด ๋กœ๊น…, ํ—ค๋” ์„ค์ •, ๋ฐ์ดํ„ฐ ์ „์†ก ํ˜•์‹(JSON ๋˜๋Š” XML ๋“ฑ)์„ ํ•œ ๊ณณ์—์„œ ๊ด€๋ฆฌํ•  ์ˆ˜ ์žˆ๊ฒŒ ๋ฉ๋‹ˆ๋‹ค. ๋˜ํ•œ ์ด ์ ‘๊ทผ ๋ฐฉ์‹์€ API์™€์˜ ์ƒํ˜ธ์ž‘์šฉ์— ๋Œ€ํ•œ ๋ณ€๊ฒฝ ์‚ฌํ•ญ์„ ์‰ฝ๊ฒŒ ๋ฐ˜์˜ํ•  ์ˆ˜ ์žˆ๊ฒŒ ํ•˜์—ฌ, ํ”„๋กœ์ ํŠธ์˜ ์œ ์ง€๋ณด์ˆ˜์„ฑ๊ณผ ๊ฐœ๋ฐœ ํŽธ์˜์„ฑ์„ ํฌ๊ฒŒ ํ–ฅ์ƒ์‹œํ‚ต๋‹ˆ๋‹ค.

@/shared/api/api-client.ts
import { API_URL } from "@/shared/config";

export class ApiClient {
private baseUrl: string;

constructor(url: string) {
this.baseUrl = url;
}

async handleResponse<TResult>(response: Response): Promise<TResult> {
if (!response.ok) {
throw new Error(`HTTP error! Status: ${response.status}`);
}

try {
return await response.json();
} catch (error) {
throw new Error("Error parsing JSON response");
}
}

public async get<TResult = unknown>(
endpoint: string,
queryParams?: Record<string, string | number>,
): Promise<TResult> {
const url = new URL(endpoint, this.baseUrl);

if (queryParams) {
Object.entries(queryParams).forEach(([key, value]) => {
url.searchParams.append(key, value.toString());
});
}
const response = await fetch(url.toString(), {
method: "GET",
headers: {
"Content-Type": "application/json",
},
});

return this.handleResponse<TResult>(response);
}

public async post<TResult = unknown, TData = Record<string, unknown>>(
endpoint: string,
body: TData,
): Promise<TResult> {
const response = await fetch(`${this.baseUrl}${endpoint}`, {
method: "POST",
headers: {
"Content-Type": "application/json",
},
body: JSON.stringify(body),
});

return this.handleResponse<TResult>(response);
}
}

export const apiClient = new ApiClient(API_URL);

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