카테고리 관련 API 요청을 TanStack Query로 마이그레이션 (WiP)

eslint.config.js

@@ -1,11 +1,13 @@
-import prettier from "eslint-config-prettier";
-import js from "@eslint/js";
 import { includeIgnoreFile } from "@eslint/compat";
+import js from "@eslint/js";
+import svelteQuery from "@tanstack/eslint-plugin-query";
+import prettier from "eslint-config-prettier";
 import svelte from "eslint-plugin-svelte";
 import tailwind from "eslint-plugin-tailwindcss";
 import globals from "globals";
-import { fileURLToPath } from "node:url";
 import ts from "typescript-eslint";
+import { fileURLToPath } from "url";
+
 const gitignorePath = fileURLToPath(new URL("./.gitignore", import.meta.url));
 
 export default ts.config(
@@ -26,11 +28,11 @@ export default ts.config(
   },
   {
     files: ["**/*.svelte"],
-
     languageOptions: {
       parserOptions: {
         parser: ts.parser,
       },
     },
   },
+  ...svelteQuery.configs["flat/recommended"],
 );

package.json

@@ -21,6 +21,8 @@
     "@sveltejs/adapter-node": "^5.2.13",
     "@sveltejs/kit": "^2.22.5",
     "@sveltejs/vite-plugin-svelte": "^4.0.4",
+    "@tanstack/eslint-plugin-query": "^5.81.2",
+    "@tanstack/svelte-query": "^5.83.0",
     "@types/file-saver": "^2.0.7",
     "@types/ms": "^0.7.34",
     "@types/node-schedule": "^2.1.8",

pnpm-lock.yaml

@@ -48,6 +48,12 @@ importers:
       '@sveltejs/vite-plugin-svelte':
         specifier: ^4.0.4
         version: 4.0.4(svelte@5.35.6)(vite@5.4.19(@types/node@24.0.13))
+      '@tanstack/eslint-plugin-query':
+        specifier: ^5.81.2
+        version: 5.81.2(eslint@9.30.1(jiti@2.4.2))(typescript@5.8.3)
+      '@tanstack/svelte-query':
+        specifier: ^5.83.0
+        version: 5.83.0(svelte@5.35.6)
       '@types/file-saver':
         specifier: ^2.0.7
         version: 2.0.7
@@ -583,6 +589,19 @@ packages:
       svelte: ^5.0.0-next.96 || ^5.0.0
       vite: ^5.0.0
 
+  '@tanstack/eslint-plugin-query@5.81.2':
+    resolution: {integrity: sha512-h4k6P6fm5VhKP5NkK+0TTVpGGyKQdx6tk7NYYG7J7PkSu7ClpLgBihw7yzK8N3n5zPaF3IMyErxfoNiXWH/3/A==}
+    peerDependencies:
+      eslint: ^8.57.0 || ^9.0.0
+
+  '@tanstack/query-core@5.83.0':
+    resolution: {integrity: sha512-0M8dA+amXUkyz5cVUm/B+zSk3xkQAcuXuz5/Q/LveT4ots2rBpPTZOzd7yJa2Utsf8D2Upl5KyjhHRY+9lB/XA==}
+
+  '@tanstack/svelte-query@5.83.0':
+    resolution: {integrity: sha512-8tNXhuoizntZXnAzo4yqUWgZZnklQkXGUNpb3YreW68DyCBhhrGbErnrODQs3fVc2ABcMvAHIki5uErbdzXH1A==}
+    peerDependencies:
+      svelte: ^3.54.0 || ^4.0.0 || ^5.0.0
+
   '@types/cookie@0.6.0':
     resolution: {integrity: sha512-4Kh9a6B2bQciAhf7FSuMRRkUWecJgJu9nPnx3yzpsfXX/c50REIqpHY4C82bXP90qrLtXtkDxTZosYO3UpOwlA==}
 
@@ -2368,6 +2387,21 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
+  '@tanstack/eslint-plugin-query@5.81.2(eslint@9.30.1(jiti@2.4.2))(typescript@5.8.3)':
+    dependencies:
+      '@typescript-eslint/utils': 8.36.0(eslint@9.30.1(jiti@2.4.2))(typescript@5.8.3)
+      eslint: 9.30.1(jiti@2.4.2)
+    transitivePeerDependencies:
+      - supports-color
+      - typescript
+
+  '@tanstack/query-core@5.83.0': {}
+
+  '@tanstack/svelte-query@5.83.0(svelte@5.35.6)':
+    dependencies:
+      '@tanstack/query-core': 5.83.0
+      svelte: 5.35.6
+
   '@types/cookie@0.6.0': {}
 
   '@types/estree@1.0.8': {}

src/lib/components/molecules/Categories/Categories.svelte

@@ -1,14 +1,16 @@
 <script lang="ts">
-  import { untrack, type Component } from "svelte";
+  import type { Component } from "svelte";
   import type { SvelteHTMLElements } from "svelte/elements";
-  import { get, type Writable } from "svelte/store";
+  import { derived } from "svelte/store";
-  import type { CategoryInfo } from "$lib/modules/filesystem";
+  import type { CategoryId } from "$lib/indexedDB";
+  import { getCategoryInfo, type SubCategoryInfo } from "$lib/modules/filesystem2";
   import { SortBy, sortEntries } from "$lib/modules/util";
+  import { masterKeyStore } from "$lib/stores";
   import Category from "./Category.svelte";
   import type { SelectedCategory } from "./service";
 
   interface Props {
-    categories: Writable<CategoryInfo | null>[];
+    categoryIds: CategoryId[];
     categoryMenuIcon?: Component<SvelteHTMLElements["svg"]>;
     onCategoryClick: (category: SelectedCategory) => void;
     onCategoryMenuClick?: (category: SelectedCategory) => void;
@@ -16,42 +18,33 @@
   }
 
   let {
-    categories,
+    categoryIds,
     categoryMenuIcon,
     onCategoryClick,
     onCategoryMenuClick,
     sortBy = SortBy.NAME_ASC,
   }: Props = $props();
 
-  let categoriesWithName: { name?: string; info: Writable<CategoryInfo | null> }[] = $state([]);
+  let categories = $derived(
-
+    derived(
-  $effect(() => {
+      categoryIds.map((id) => getCategoryInfo(id, $masterKeyStore?.get(1)?.key!)),
-    categoriesWithName = categories.map((category) => ({
+      (infos) => {
-      name: get(category)?.name,
+        const categories = infos
-      info: category,
+          .filter(($info) => $info.status === "success")
+          .map(($info) => ({
+            name: $info.data.name,
+            info: $info.data as SubCategoryInfo,
           }));
-
+        sortEntries(categories, sortBy);
-    const sort = () => {
+        return categories;
-      sortEntries(categoriesWithName, sortBy);
+      },
-    };
+    ),
-    return untrack(() => {
-      sort();
-
-      const unsubscribes = categoriesWithName.map((category) =>
-        category.info.subscribe((value) => {
-          if (category.name === value?.name) return;
-          category.name = value?.name;
-          sort();
-        }),
   );
-      return () => unsubscribes.forEach((unsubscribe) => unsubscribe());
-    });
-  });
 </script>
 
-{#if categoriesWithName.length > 0}
+{#if $categories.length > 0}
   <div class="space-y-1">
-    {#each categoriesWithName as { info }}
+    {#each $categories as { info }}
       <Category
         {info}
         menuIcon={categoryMenuIcon}

src/lib/components/molecules/Categories/Category.svelte

@@ -1,14 +1,13 @@
 <script lang="ts">
   import type { Component } from "svelte";
   import type { SvelteHTMLElements } from "svelte/elements";
-  import type { Writable } from "svelte/store";
   import { ActionEntryButton } from "$lib/components/atoms";
   import { CategoryLabel } from "$lib/components/molecules";
-  import type { CategoryInfo } from "$lib/modules/filesystem";
+  import type { SubCategoryInfo } from "$lib/modules/filesystem2";
   import type { SelectedCategory } from "./service";
 
   interface Props {
-    info: Writable<CategoryInfo | null>;
+    info: SubCategoryInfo;
     menuIcon?: Component<SvelteHTMLElements["svg"]>;
     onclick: (category: SelectedCategory) => void;
     onMenuClick?: (category: SelectedCategory) => void;
@@ -17,27 +16,25 @@
   let { info, menuIcon, onclick, onMenuClick }: Props = $props();
 
   const openCategory = () => {
-    const { id, dataKey, dataKeyVersion, name } = $info as CategoryInfo;
+    const { id, dataKey, dataKeyVersion, name } = info;
     if (!dataKey || !dataKeyVersion) return; // TODO: Error handling
 
     onclick({ id, dataKey, dataKeyVersion, name });
   };
 
   const openMenu = () => {
-    const { id, dataKey, dataKeyVersion, name } = $info as CategoryInfo;
+    const { id, dataKey, dataKeyVersion, name } = info;
     if (!dataKey || !dataKeyVersion) return; // TODO: Error handling
 
     onMenuClick!({ id, dataKey, dataKeyVersion, name });
   };
 </script>
 
-{#if $info}
 <ActionEntryButton
   class="h-12"
   onclick={openCategory}
   actionButtonIcon={menuIcon}
   onActionButtonClick={openMenu}
 >
-    <CategoryLabel name={$info.name!} />
+  <CategoryLabel name={info.name} />
 </ActionEntryButton>
-{/if}

src/lib/components/molecules/SubCategories.svelte

@@ -1,10 +1,8 @@
 <script lang="ts">
   import type { Component } from "svelte";
   import type { ClassValue, SvelteHTMLElements } from "svelte/elements";
-  import type { Writable } from "svelte/store";
   import { Categories, IconEntryButton, type SelectedCategory } from "$lib/components/molecules";
-  import { getCategoryInfo, type CategoryInfo } from "$lib/modules/filesystem";
+  import type { CategoryInfo } from "$lib/modules/filesystem2";
-  import { masterKeyStore } from "$lib/stores";
 
   import IconAddCircle from "~icons/material-symbols/add-circle";
 
@@ -27,14 +25,6 @@
     subCategoryCreatePosition = "bottom",
     subCategoryMenuIcon,
   }: Props = $props();
-
-  let subCategories: Writable<CategoryInfo | null>[] = $state([]);
-
-  $effect(() => {
-    subCategories = info.subCategoryIds.map((id) =>
-      getCategoryInfo(id, $masterKeyStore?.get(1)?.key!),
-    );
-  });
 </script>
 
 <div class={["space-y-1", className]}>
@@ -55,7 +45,7 @@
   {/if}
   {#key info}
     <Categories
-      categories={subCategories}
+      categoryIds={info.subCategoryIds}
       categoryMenuIcon={subCategoryMenuIcon}
       onCategoryClick={onSubCategoryClick}
       onCategoryMenuClick={onSubCategoryMenuClick}

src/lib/components/organisms/Category/Category.svelte

@@ -1,9 +1,8 @@
 <script lang="ts">
-  import { untrack } from "svelte";
+  import { derived } from "svelte/store";
-  import { get, type Writable } from "svelte/store";
   import { CheckBox } from "$lib/components/atoms";
   import { SubCategories, type SelectedCategory } from "$lib/components/molecules";
-  import { getFileInfo, type FileInfo, type CategoryInfo } from "$lib/modules/filesystem";
+  import { getFileInfo, type CategoryInfo } from "$lib/modules/filesystem2";
   import { SortBy, sortEntries } from "$lib/modules/util";
   import { masterKeyStore } from "$lib/stores";
   import File from "./File.svelte";
@@ -19,7 +18,7 @@
     onSubCategoryCreateClick: () => void;
     onSubCategoryMenuClick: (subCategory: SelectedCategory) => void;
     sortBy?: SortBy;
-    isFileRecursive: boolean;
+    isFileRecursive?: boolean;
   }
 
   let {
@@ -33,39 +32,35 @@
     isFileRecursive = $bindable(),
   }: Props = $props();
 
-  let files: { name?: string; info: Writable<FileInfo | null>; isRecursive: boolean }[] = $state(
+  let fileInfos = $derived(
-    [],
-  );
-
-  $effect(() => {
-    files =
     info.files
       ?.filter(({ isRecursive }) => isFileRecursive || !isRecursive)
-        .map(({ id, isRecursive }) => {
+      .map(({ id, isRecursive }) => ({
-          const info = getFileInfo(id, $masterKeyStore?.get(1)?.key!);
+        info: getFileInfo(id, $masterKeyStore?.get(1)?.key!),
-          return {
-            name: get(info)?.name,
-            info,
         isRecursive,
-          };
+      })) ?? [],
-        }) ?? [];
+  );
-
+  let files = $derived(
-    const sort = () => {
+    derived(
-      sortEntries(files, sortBy);
+      fileInfos.map(({ info }) => info),
-    };
+      (infos) => {
-    return untrack(() => {
+        const files = infos
-      sort();
+          .map(($info, i) => {
-
+            if ($info.status === "success") {
-      const unsubscribes = files.map((file) =>
+              return {
-        file.info.subscribe((value) => {
+                name: $info.data.name,
-          if (file.name === value?.name) return;
+                isRecursive: fileInfos[i]!.isRecursive,
-          file.name = value?.name;
+                info: $info.data,
-          sort();
+              };
-        }),
+            }
+            return undefined;
+          })
+          .filter((info) => info !== undefined);
+        sortEntries(files, sortBy);
+        return files;
+      },
+    ),
   );
-      return () => unsubscribes.forEach((unsubscribe) => unsubscribe());
-    });
-  });
 </script>
 
 <div class="space-y-4">
@@ -85,13 +80,15 @@
     <div class="space-y-4 bg-white p-4">
       <div class="flex items-center justify-between">
         <p class="text-lg font-bold text-gray-800">파일</p>
+        {#if isFileRecursive !== undefined}
           <CheckBox bind:checked={isFileRecursive}>
             <p class="font-medium">하위 카테고리의 파일</p>
           </CheckBox>
+        {/if}
       </div>
       <div class="space-y-1">
         {#key info}
-          {#each files as { info, isRecursive }}
+          {#each $files as { info, isRecursive }}
             <File
               {info}
               onclick={onFileClick}

src/lib/components/organisms/Category/File.svelte

@@ -1,14 +1,13 @@
 <script lang="ts">
-  import type { Writable } from "svelte/store";
   import { ActionEntryButton } from "$lib/components/atoms";
   import { DirectoryEntryLabel } from "$lib/components/molecules";
-  import type { FileInfo } from "$lib/modules/filesystem";
+  import type { FileInfo } from "$lib/modules/filesystem2";
   import { requestFileThumbnailDownload, type SelectedFile } from "./service";
 
   import IconClose from "~icons/material-symbols/close";
 
   interface Props {
-    info: Writable<FileInfo | null>;
+    info: FileInfo;
     onclick: (selectedFile: SelectedFile) => void;
     onRemoveClick?: (selectedFile: SelectedFile) => void;
   }
@@ -18,22 +17,22 @@
   let thumbnail: string | undefined = $state();
 
   const openFile = () => {
-    const { id, dataKey, dataKeyVersion, name } = $info as FileInfo;
+    const { id, dataKey, dataKeyVersion, name } = info;
     if (!dataKey || !dataKeyVersion) return; // TODO: Error handling
 
     onclick({ id, dataKey, dataKeyVersion, name });
   };
 
   const removeFile = () => {
-    const { id, dataKey, dataKeyVersion, name } = $info as FileInfo;
+    const { id, dataKey, dataKeyVersion, name } = info;
     if (!dataKey || !dataKeyVersion) return; // TODO: Error handling
 
     onRemoveClick!({ id, dataKey, dataKeyVersion, name });
   };
 
   $effect(() => {
-    if ($info?.dataKey) {
+    if (info.dataKey) {
-      requestFileThumbnailDownload($info.id, $info.dataKey)
+      requestFileThumbnailDownload(info.id, info.dataKey)
         .then((thumbnailUrl) => {
           thumbnail = thumbnailUrl ?? undefined;
         })
@@ -47,13 +46,11 @@
   });
 </script>
 
-{#if $info}
 <ActionEntryButton
   class="h-12"
   onclick={openFile}
   actionButtonIcon={onRemoveClick && IconClose}
   onActionButtonClick={removeFile}
 >
-    <DirectoryEntryLabel type="file" {thumbnail} name={$info.name} />
+  <DirectoryEntryLabel type="file" {thumbnail} name={info.name} />
 </ActionEntryButton>
-{/if}

src/lib/hooks/callApi.ts

@@ -1,11 +1,24 @@
-export const callGetApi = async (input: RequestInfo, fetchInternal = fetch) => {
+interface FetchOptions {
-  return await fetchInternal(input);
+  fetch?: typeof fetch;
+  signal?: AbortSignal;
+}
+
+export const callGetApi = async (
+  input: RequestInfo,
+  { fetch = globalThis.fetch, signal }: FetchOptions = {},
+) => {
+  return await fetch(input, { method: "GET", signal });
 };
 
-export const callPostApi = async <T>(input: RequestInfo, payload?: T, fetchInternal = fetch) => {
+export const callPostApi = async <T>(
-  return await fetchInternal(input, {
+  input: RequestInfo,
+  payload?: T,
+  { fetch = globalThis.fetch, signal }: FetchOptions = {},
+) => {
+  return await fetch(input, {
     method: "POST",
     headers: { "Content-Type": "application/json" },
     body: payload ? JSON.stringify(payload) : undefined,
+    signal,
   });
 };

src/lib/indexedDB/filesystem.ts

@@ -62,6 +62,10 @@ export const storeDirectoryInfo = async (directoryInfo: DirectoryInfo) => {
   await filesystem.directory.put(directoryInfo);
 };
 
+export const updateDirectoryInfo = async (id: number, changes: { name?: string }) => {
+  await filesystem.directory.update(id, changes);
+};
+
 export const deleteDirectoryInfo = async (id: number) => {
   await filesystem.directory.delete(id);
 };
@@ -82,6 +86,10 @@ export const storeFileInfo = async (fileInfo: FileInfo) => {
   await filesystem.file.put(fileInfo);
 };
 
+export const updateFileInfo = async (id: number, changes: { name?: string }) => {
+  await filesystem.file.update(id, changes);
+};
+
 export const deleteFileInfo = async (id: number) => {
   await filesystem.file.delete(id);
 };
@@ -98,7 +106,10 @@ export const storeCategoryInfo = async (categoryInfo: CategoryInfo) => {
   await filesystem.category.put(categoryInfo);
 };
 
-export const updateCategoryInfo = async (id: number, changes: { isFileRecursive?: boolean }) => {
+export const updateCategoryInfo = async (
+  id: number,
+  changes: { name?: string; isFileRecursive?: boolean },
+) => {
   await filesystem.category.update(id, changes);
 };
 

src/lib/modules/file/upload.ts

@@ -5,6 +5,7 @@ import { writable, type Writable } from "svelte/store";
 import {
   encodeToBase64,
   generateDataKey,
+  makeAESKeyNonextractable,
   wrapDataKey,
   encryptData,
   encryptString,
@@ -118,12 +119,14 @@ const encryptFile = limitFunction(
     });
 
     return {
+      dataKey: await makeAESKeyNonextractable(dataKey),
       dataKeyWrapped,
       dataKeyVersion,
       fileType,
       fileEncrypted,
       fileEncryptedHash,
       nameEncrypted,
+      createdAt,
       createdAtEncrypted,
       lastModifiedAtEncrypted,
       thumbnail: thumbnailEncrypted && { plaintext: thumbnailBuffer, ...thumbnailEncrypted },
@@ -176,9 +179,7 @@ export const uploadFile = async (
   hmacSecret: HmacSecret,
   masterKey: MasterKey,
   onDuplicate: () => Promise<boolean>,
-): Promise<
+) => {
-  { fileId: number; fileBuffer: ArrayBuffer; thumbnailBuffer?: ArrayBuffer } | undefined
-> => {
   const status = writable<FileUploadStatus>({
     name: file.name,
     parentId,
@@ -208,12 +209,14 @@ export const uploadFile = async (
     }
 
     const {
+      dataKey,
       dataKeyWrapped,
       dataKeyVersion,
       fileType,
       fileEncrypted,
       fileEncryptedHash,
       nameEncrypted,
+      createdAt,
       createdAtEncrypted,
       lastModifiedAtEncrypted,
       thumbnail,
@@ -256,7 +259,16 @@ export const uploadFile = async (
     }
 
     const { fileId } = await requestFileUpload(status, form, thumbnailForm);
-    return { fileId, fileBuffer, thumbnailBuffer: thumbnail?.plaintext };
+    return {
+      fileId,
+      fileDataKey: dataKey,
+      fileDataKeyVersion: dataKeyVersion,
+      fileType,
+      fileEncryptedIv: fileEncrypted.iv,
+      fileCreatedAt: createdAt,
+      fileBuffer,
+      thumbnailBuffer: thumbnail?.plaintext,
+    };
   } catch (e) {
     status.update((value) => {
       value.status = "error";

src/lib/modules/filesystem.ts

@@ -1,360 +0,0 @@
-import { get, writable, type Writable } from "svelte/store";
-import { callGetApi } from "$lib/hooks";
-import {
-  getDirectoryInfos as getDirectoryInfosFromIndexedDB,
-  getDirectoryInfo as getDirectoryInfoFromIndexedDB,
-  storeDirectoryInfo,
-  deleteDirectoryInfo,
-  getFileInfos as getFileInfosFromIndexedDB,
-  getFileInfo as getFileInfoFromIndexedDB,
-  storeFileInfo,
-  deleteFileInfo,
-  getCategoryInfos as getCategoryInfosFromIndexedDB,
-  getCategoryInfo as getCategoryInfoFromIndexedDB,
-  storeCategoryInfo,
-  updateCategoryInfo as updateCategoryInfoInIndexedDB,
-  deleteCategoryInfo,
-  type DirectoryId,
-  type CategoryId,
-} from "$lib/indexedDB";
-import { unwrapDataKey, decryptString } from "$lib/modules/crypto";
-import type {
-  CategoryInfoResponse,
-  CategoryFileListResponse,
-  DirectoryInfoResponse,
-  FileInfoResponse,
-} from "$lib/server/schemas";
-
-export type DirectoryInfo =
-  | {
-      id: "root";
-      dataKey?: undefined;
-      dataKeyVersion?: undefined;
-      name?: undefined;
-      subDirectoryIds: number[];
-      fileIds: number[];
-    }
-  | {
-      id: number;
-      dataKey?: CryptoKey;
-      dataKeyVersion?: Date;
-      name: string;
-      subDirectoryIds: number[];
-      fileIds: number[];
-    };
-
-export interface FileInfo {
-  id: number;
-  dataKey?: CryptoKey;
-  dataKeyVersion?: Date;
-  contentType: string;
-  contentIv?: string;
-  name: string;
-  createdAt?: Date;
-  lastModifiedAt: Date;
-  categoryIds: number[];
-}
-
-export type CategoryInfo =
-  | {
-      id: "root";
-      dataKey?: undefined;
-      dataKeyVersion?: undefined;
-      name?: undefined;
-      subCategoryIds: number[];
-      files?: undefined;
-      isFileRecursive?: undefined;
-    }
-  | {
-      id: number;
-      dataKey?: CryptoKey;
-      dataKeyVersion?: Date;
-      name: string;
-      subCategoryIds: number[];
-      files: { id: number; isRecursive: boolean }[];
-      isFileRecursive: boolean;
-    };
-
-const directoryInfoStore = new Map<DirectoryId, Writable<DirectoryInfo | null>>();
-const fileInfoStore = new Map<number, Writable<FileInfo | null>>();
-const categoryInfoStore = new Map<CategoryId, Writable<CategoryInfo | null>>();
-
-const fetchDirectoryInfoFromIndexedDB = async (
-  id: DirectoryId,
-  info: Writable<DirectoryInfo | null>,
-) => {
-  if (get(info)) return;
-
-  const [directory, subDirectories, files] = await Promise.all([
-    id !== "root" ? getDirectoryInfoFromIndexedDB(id) : undefined,
-    getDirectoryInfosFromIndexedDB(id),
-    getFileInfosFromIndexedDB(id),
-  ]);
-  const subDirectoryIds = subDirectories.map(({ id }) => id);
-  const fileIds = files.map(({ id }) => id);
-
-  if (id === "root") {
-    info.set({ id, subDirectoryIds, fileIds });
-  } else {
-    if (!directory) return;
-    info.set({ id, name: directory.name, subDirectoryIds, fileIds });
-  }
-};
-
-const fetchDirectoryInfoFromServer = async (
-  id: DirectoryId,
-  info: Writable<DirectoryInfo | null>,
-  masterKey: CryptoKey,
-) => {
-  const res = await callGetApi(`/api/directory/${id}`);
-  if (res.status === 404) {
-    info.set(null);
-    await deleteDirectoryInfo(id as number);
-    return;
-  } else if (!res.ok) {
-    throw new Error("Failed to fetch directory information");
-  }
-
-  const {
-    metadata,
-    subDirectories: subDirectoryIds,
-    files: fileIds,
-  }: DirectoryInfoResponse = await res.json();
-
-  if (id === "root") {
-    info.set({ id, subDirectoryIds, fileIds });
-  } else {
-    const { dataKey } = await unwrapDataKey(metadata!.dek, masterKey);
-    const name = await decryptString(metadata!.name, metadata!.nameIv, dataKey);
-
-    info.set({
-      id,
-      dataKey,
-      dataKeyVersion: new Date(metadata!.dekVersion),
-      name,
-      subDirectoryIds,
-      fileIds,
-    });
-    await storeDirectoryInfo({ id, parentId: metadata!.parent, name });
-  }
-};
-
-const fetchDirectoryInfo = async (
-  id: DirectoryId,
-  info: Writable<DirectoryInfo | null>,
-  masterKey: CryptoKey,
-) => {
-  await fetchDirectoryInfoFromIndexedDB(id, info);
-  await fetchDirectoryInfoFromServer(id, info, masterKey);
-};
-
-export const getDirectoryInfo = (id: DirectoryId, masterKey: CryptoKey) => {
-  // TODO: MEK rotation
-
-  let info = directoryInfoStore.get(id);
-  if (!info) {
-    info = writable(null);
-    directoryInfoStore.set(id, info);
-  }
-
-  fetchDirectoryInfo(id, info, masterKey); // Intended
-  return info;
-};
-
-const fetchFileInfoFromIndexedDB = async (id: number, info: Writable<FileInfo | null>) => {
-  if (get(info)) return;
-
-  const file = await getFileInfoFromIndexedDB(id);
-  if (!file) return;
-
-  info.set(file);
-};
-
-const decryptDate = async (ciphertext: string, iv: string, dataKey: CryptoKey) => {
-  return new Date(parseInt(await decryptString(ciphertext, iv, dataKey), 10));
-};
-
-const fetchFileInfoFromServer = async (
-  id: number,
-  info: Writable<FileInfo | null>,
-  masterKey: CryptoKey,
-) => {
-  const res = await callGetApi(`/api/file/${id}`);
-  if (res.status === 404) {
-    info.set(null);
-    await deleteFileInfo(id);
-    return;
-  } else if (!res.ok) {
-    throw new Error("Failed to fetch file information");
-  }
-
-  const metadata: FileInfoResponse = await res.json();
-  const { dataKey } = await unwrapDataKey(metadata.dek, masterKey);
-
-  const name = await decryptString(metadata.name, metadata.nameIv, dataKey);
-  const createdAt =
-    metadata.createdAt && metadata.createdAtIv
-      ? await decryptDate(metadata.createdAt, metadata.createdAtIv, dataKey)
-      : undefined;
-  const lastModifiedAt = await decryptDate(
-    metadata.lastModifiedAt,
-    metadata.lastModifiedAtIv,
-    dataKey,
-  );
-
-  info.set({
-    id,
-    dataKey,
-    dataKeyVersion: new Date(metadata.dekVersion),
-    contentType: metadata.contentType,
-    contentIv: metadata.contentIv,
-    name,
-    createdAt,
-    lastModifiedAt,
-    categoryIds: metadata.categories,
-  });
-  await storeFileInfo({
-    id,
-    parentId: metadata.parent,
-    name,
-    contentType: metadata.contentType,
-    createdAt,
-    lastModifiedAt,
-    categoryIds: metadata.categories,
-  });
-};
-
-const fetchFileInfo = async (id: number, info: Writable<FileInfo | null>, masterKey: CryptoKey) => {
-  await fetchFileInfoFromIndexedDB(id, info);
-  await fetchFileInfoFromServer(id, info, masterKey);
-};
-
-export const getFileInfo = (fileId: number, masterKey: CryptoKey) => {
-  // TODO: MEK rotation
-
-  let info = fileInfoStore.get(fileId);
-  if (!info) {
-    info = writable(null);
-    fileInfoStore.set(fileId, info);
-  }
-
-  fetchFileInfo(fileId, info, masterKey); // Intended
-  return info;
-};
-
-const fetchCategoryInfoFromIndexedDB = async (
-  id: CategoryId,
-  info: Writable<CategoryInfo | null>,
-) => {
-  if (get(info)) return;
-
-  const [category, subCategories] = await Promise.all([
-    id !== "root" ? getCategoryInfoFromIndexedDB(id) : undefined,
-    getCategoryInfosFromIndexedDB(id),
-  ]);
-  const subCategoryIds = subCategories.map(({ id }) => id);
-
-  if (id === "root") {
-    info.set({ id, subCategoryIds });
-  } else {
-    if (!category) return;
-    info.set({
-      id,
-      name: category.name,
-      subCategoryIds,
-      files: category.files,
-      isFileRecursive: category.isFileRecursive,
-    });
-  }
-};
-
-const fetchCategoryInfoFromServer = async (
-  id: CategoryId,
-  info: Writable<CategoryInfo | null>,
-  masterKey: CryptoKey,
-) => {
-  let res = await callGetApi(`/api/category/${id}`);
-  if (res.status === 404) {
-    info.set(null);
-    await deleteCategoryInfo(id as number);
-    return;
-  } else if (!res.ok) {
-    throw new Error("Failed to fetch category information");
-  }
-
-  const { metadata, subCategories }: CategoryInfoResponse = await res.json();
-
-  if (id === "root") {
-    info.set({ id, subCategoryIds: subCategories });
-  } else {
-    const { dataKey } = await unwrapDataKey(metadata!.dek, masterKey);
-    const name = await decryptString(metadata!.name, metadata!.nameIv, dataKey);
-
-    res = await callGetApi(`/api/category/${id}/file/list?recurse=true`);
-    if (!res.ok) {
-      throw new Error("Failed to fetch category files");
-    }
-
-    const { files }: CategoryFileListResponse = await res.json();
-    const filesMapped = files.map(({ file, isRecursive }) => ({ id: file, isRecursive }));
-    let isFileRecursive: boolean | undefined = undefined;
-
-    info.update((value) => {
-      const newValue = {
-        isFileRecursive: false,
-        ...value,
-        id,
-        dataKey,
-        dataKeyVersion: new Date(metadata!.dekVersion),
-        name,
-        subCategoryIds: subCategories,
-        files: filesMapped,
-      };
-      isFileRecursive = newValue.isFileRecursive;
-      return newValue;
-    });
-    await storeCategoryInfo({
-      id,
-      parentId: metadata!.parent,
-      name,
-      files: filesMapped,
-      isFileRecursive: isFileRecursive!,
-    });
-  }
-};
-
-const fetchCategoryInfo = async (
-  id: CategoryId,
-  info: Writable<CategoryInfo | null>,
-  masterKey: CryptoKey,
-) => {
-  await fetchCategoryInfoFromIndexedDB(id, info);
-  await fetchCategoryInfoFromServer(id, info, masterKey);
-};
-
-export const getCategoryInfo = (categoryId: CategoryId, masterKey: CryptoKey) => {
-  // TODO: MEK rotation
-
-  let info = categoryInfoStore.get(categoryId);
-  if (!info) {
-    info = writable(null);
-    categoryInfoStore.set(categoryId, info);
-  }
-
-  fetchCategoryInfo(categoryId, info, masterKey); // Intended
-  return info;
-};
-
-export const updateCategoryInfo = async (
-  categoryId: number,
-  changes: { isFileRecursive?: boolean },
-) => {
-  await updateCategoryInfoInIndexedDB(categoryId, changes);
-  categoryInfoStore.get(categoryId)?.update((value) => {
-    if (!value) return value;
-    if (changes.isFileRecursive !== undefined) {
-      value.isFileRecursive = changes.isFileRecursive;
-    }
-    return value;
-  });
-};

src/lib/modules/filesystem2/category.ts

@@ -0,0 +1,294 @@
+import { useQueryClient, createQuery, createMutation } from "@tanstack/svelte-query";
+import { callGetApi, callPostApi } from "$lib/hooks";
+import {
+  getCategoryInfos as getCategoryInfosFromIndexedDB,
+  getCategoryInfo as getCategoryInfoFromIndexedDB,
+  storeCategoryInfo,
+  updateCategoryInfo,
+  deleteCategoryInfo,
+  type CategoryId,
+} from "$lib/indexedDB";
+import {
+  generateDataKey,
+  wrapDataKey,
+  unwrapDataKey,
+  encryptString,
+  decryptString,
+} from "$lib/modules/crypto";
+import type {
+  CategoryInfoResponse,
+  CategoryFileListResponse,
+  CategoryRenameRequest,
+  CategoryCreateRequest,
+  CategoryCreateResponse,
+} from "$lib/server/schemas";
+import type { MasterKey } from "$lib/stores";
+
+export type CategoryInfo =
+  | {
+      id: "root";
+      dataKey?: undefined;
+      dataKeyVersion?: undefined;
+      name?: undefined;
+      subCategoryIds: number[];
+      files?: undefined;
+      isFileRecursive?: undefined;
+    }
+  | {
+      id: number;
+      dataKey?: CryptoKey;
+      dataKeyVersion?: Date;
+      name: string;
+      subCategoryIds: number[];
+      files: { id: number; isRecursive: boolean }[];
+      isFileRecursive: boolean;
+    };
+export type SubCategoryInfo = CategoryInfo & { id: number };
+
+let temporaryIdCounter = -1;
+
+const getInitialCategoryInfo = async (id: CategoryId) => {
+  const [category, subCategories] = await Promise.all([
+    id !== "root" ? getCategoryInfoFromIndexedDB(id) : undefined,
+    getCategoryInfosFromIndexedDB(id),
+  ]);
+  const subCategoryIds = subCategories.map(({ id }) => id);
+
+  if (id === "root") {
+    return { id, subCategoryIds };
+  } else if (category) {
+    return {
+      id,
+      name: category.name,
+      subCategoryIds,
+      files: category.files,
+      isFileRecursive: category.isFileRecursive,
+    };
+  }
+  return undefined;
+};
+
+export const getCategoryInfo = (id: CategoryId, masterKey: CryptoKey) => {
+  return createQuery<CategoryInfo>({
+    queryKey: ["category", id],
+    queryFn: async ({ client, signal }) => {
+      if (!client.getQueryData<CategoryInfo>(["category", id])) {
+        const initialInfo = await getInitialCategoryInfo(id);
+        if (initialInfo) {
+          setTimeout(() => client.invalidateQueries({ queryKey: ["category", id] }), 0);
+          return initialInfo;
+        }
+      }
+
+      const res = await callGetApi(`/api/category/${id}`, { signal }); // TODO: 404
+      const { metadata, subCategories }: CategoryInfoResponse = await res.json();
+
+      if (id === "root") {
+        return { id, subCategoryIds: subCategories };
+      } else {
+        const { dataKey } = await unwrapDataKey(metadata!.dek, masterKey);
+        const name = await decryptString(metadata!.name, metadata!.nameIv, dataKey);
+
+        const res = await callGetApi(`/api/category/${id}/file/list?recurse=true`); // TODO: Error Handling
+        const { files }: CategoryFileListResponse = await res.json();
+        const filesMapped = files.map(({ file, isRecursive }) => ({ id: file, isRecursive }));
+
+        const prevInfo = client.getQueryData<CategoryInfo>(["category", id]);
+        await storeCategoryInfo({
+          id,
+          parentId: metadata!.parent,
+          name,
+          files: filesMapped,
+          isFileRecursive: prevInfo?.isFileRecursive ?? false,
+        });
+        return {
+          id,
+          dataKey,
+          dataKeyVersion: new Date(metadata!.dekVersion),
+          name,
+          subCategoryIds: subCategories,
+          files: filesMapped,
+          isFileRecursive: prevInfo?.isFileRecursive ?? false,
+        };
+      }
+    },
+    staleTime: Infinity,
+  });
+};
+
+export type CategoryInfoStore = ReturnType<typeof getCategoryInfo>;
+
+export const useCategoryCreation = (parentId: CategoryId, masterKey: MasterKey) => {
+  const queryClient = useQueryClient();
+  return createMutation<void, Error, { name: string }, { tempId: number }>({
+    mutationFn: async ({ name }) => {
+      const { dataKey, dataKeyVersion } = await generateDataKey();
+      const nameEncrypted = await encryptString(name, dataKey);
+
+      const res = await callPostApi<CategoryCreateRequest>("/api/category/create", {
+        parent: parentId,
+        mekVersion: masterKey.version,
+        dek: await wrapDataKey(dataKey, masterKey.key),
+        dekVersion: dataKeyVersion.toISOString(),
+        name: nameEncrypted.ciphertext,
+        nameIv: nameEncrypted.iv,
+      });
+      if (!res.ok) throw new Error("Failed to create category");
+
+      const { category: id }: CategoryCreateResponse = await res.json();
+      queryClient.setQueryData<CategoryInfo>(["category", id], {
+        id,
+        name,
+        dataKey,
+        dataKeyVersion,
+        subCategoryIds: [],
+        files: [],
+        isFileRecursive: false,
+      });
+      await storeCategoryInfo({ id, parentId, name, files: [], isFileRecursive: false });
+    },
+    onMutate: async ({ name }) => {
+      const tempId = temporaryIdCounter--;
+      queryClient.setQueryData<CategoryInfo>(["category", tempId], {
+        id: tempId,
+        name,
+        subCategoryIds: [],
+        files: [],
+        isFileRecursive: false,
+      });
+
+      await queryClient.cancelQueries({ queryKey: ["category", parentId] });
+      queryClient.setQueryData<CategoryInfo>(["category", parentId], (prevParentInfo) => {
+        if (!prevParentInfo) return;
+        return {
+          ...prevParentInfo,
+          subCategoryIds: [...prevParentInfo.subCategoryIds, tempId],
+        };
+      });
+
+      return { tempId };
+    },
+    onError: (_error, _variables, context) => {
+      if (context) {
+        queryClient.setQueryData<CategoryInfo>(["category", parentId], (prevParentInfo) => {
+          if (!prevParentInfo) return;
+          return {
+            ...prevParentInfo,
+            subCategoryIds: prevParentInfo.subCategoryIds.filter((id) => id !== context.tempId),
+          };
+        });
+      }
+    },
+    onSettled: () => {
+      queryClient.invalidateQueries({ queryKey: ["category", parentId] });
+    },
+  });
+};
+
+export const useCategoryRename = () => {
+  const queryClient = useQueryClient();
+  return createMutation<
+    void,
+    Error,
+    {
+      id: number;
+      dataKey: CryptoKey;
+      dataKeyVersion: Date;
+      newName: string;
+    },
+    { oldName: string | undefined }
+  >({
+    mutationFn: async ({ id, dataKey, dataKeyVersion, newName }) => {
+      const newNameEncrypted = await encryptString(newName, dataKey);
+      const res = await callPostApi<CategoryRenameRequest>(`/api/category/${id}/rename`, {
+        dekVersion: dataKeyVersion.toISOString(),
+        name: newNameEncrypted.ciphertext,
+        nameIv: newNameEncrypted.iv,
+      });
+      if (!res.ok) throw new Error("Failed to rename category");
+
+      await updateCategoryInfo(id, { name: newName });
+    },
+    onMutate: async ({ id, newName }) => {
+      await queryClient.cancelQueries({ queryKey: ["category", id] });
+
+      const prevInfo = queryClient.getQueryData<SubCategoryInfo>(["category", id]);
+      if (prevInfo) {
+        queryClient.setQueryData<CategoryInfo>(["category", id], {
+          ...prevInfo,
+          name: newName,
+        });
+      }
+
+      return { oldName: prevInfo?.name };
+    },
+    onError: (_error, { id }, context) => {
+      if (context?.oldName) {
+        queryClient.setQueryData<SubCategoryInfo>(["category", id], (prevInfo) => {
+          if (!prevInfo) return;
+          return { ...prevInfo, name: context.oldName! };
+        });
+      }
+    },
+    onSettled: (_data, _error, { id }) => {
+      queryClient.invalidateQueries({ queryKey: ["category", id] });
+    },
+  });
+};
+
+export const useCategoryDeletion = (parentId: CategoryId) => {
+  const queryClient = useQueryClient();
+  return createMutation<void, Error, { id: number }, {}>({
+    mutationFn: async ({ id }) => {
+      const res = await callPostApi(`/api/category/${id}/delete`);
+      if (!res.ok) throw new Error("Failed to delete category");
+
+      await deleteCategoryInfo(id);
+
+      // TODO: Update FileInfo
+    },
+    onMutate: async ({ id }) => {
+      await queryClient.cancelQueries({ queryKey: ["category", parentId] });
+      queryClient.setQueryData<CategoryInfo>(["category", parentId], (prevParentInfo) => {
+        if (!prevParentInfo) return;
+        return {
+          ...prevParentInfo,
+          subCategoryIds: prevParentInfo.subCategoryIds.filter((categoryId) => categoryId !== id),
+        };
+      });
+      return {};
+    },
+    onError: (_error, { id }, context) => {
+      if (context) {
+        queryClient.setQueryData<CategoryInfo>(["category", parentId], (prevParentInfo) => {
+          if (!prevParentInfo) return;
+          return {
+            ...prevParentInfo,
+            subCategoryIds: [...prevParentInfo.subCategoryIds, id],
+          };
+        });
+      }
+    },
+    onSettled: () => {
+      queryClient.invalidateQueries({ queryKey: ["category", parentId] });
+    },
+  });
+};
+
+export const useCategoryFileRecursionToggle = () => {
+  const queryClient = useQueryClient();
+  return createMutation<void, Error, { id: number; isFileRecursive: boolean }, {}>({
+    mutationFn: async ({ id, isFileRecursive }) => {
+      await updateCategoryInfo(id, { isFileRecursive });
+    },
+    onMutate: async ({ id, isFileRecursive }) => {
+      const prevInfo = queryClient.getQueryData<SubCategoryInfo>(["category", id]);
+      if (prevInfo) {
+        queryClient.setQueryData<CategoryInfo>(["category", id], {
+          ...prevInfo,
+          isFileRecursive,
+        });
+      }
+    },
+  });
+};

src/lib/modules/filesystem2/directory.ts

@@ -0,0 +1,267 @@
+import { useQueryClient, createQuery, createMutation } from "@tanstack/svelte-query";
+import { callGetApi, callPostApi } from "$lib/hooks";
+import {
+  getDirectoryInfos as getDirectoryInfosFromIndexedDB,
+  getDirectoryInfo as getDirectoryInfoFromIndexedDB,
+  storeDirectoryInfo,
+  updateDirectoryInfo,
+  deleteDirectoryInfo,
+  getFileInfos as getFileInfosFromIndexedDB,
+  deleteFileInfo,
+  type DirectoryId,
+} from "$lib/indexedDB";
+import {
+  generateDataKey,
+  wrapDataKey,
+  unwrapDataKey,
+  encryptString,
+  decryptString,
+} from "$lib/modules/crypto";
+import type {
+  DirectoryInfoResponse,
+  DirectoryDeleteResponse,
+  DirectoryRenameRequest,
+  DirectoryCreateRequest,
+  DirectoryCreateResponse,
+} from "$lib/server/schemas";
+import type { MasterKey } from "$lib/stores";
+
+export type DirectoryInfo =
+  | {
+      id: "root";
+      dataKey?: undefined;
+      dataKeyVersion?: undefined;
+      name?: undefined;
+      subDirectoryIds: number[];
+      fileIds: number[];
+    }
+  | {
+      id: number;
+      dataKey?: CryptoKey;
+      dataKeyVersion?: Date;
+      name: string;
+      subDirectoryIds: number[];
+      fileIds: number[];
+    };
+export type SubDirectoryInfo = DirectoryInfo & { id: number };
+
+let temporaryIdCounter = -1;
+
+const getInitialDirectoryInfo = async (id: DirectoryId) => {
+  const [directory, subDirectories, files] = await Promise.all([
+    id !== "root" ? getDirectoryInfoFromIndexedDB(id) : undefined,
+    getDirectoryInfosFromIndexedDB(id),
+    getFileInfosFromIndexedDB(id),
+  ]);
+  const subDirectoryIds = subDirectories.map(({ id }) => id);
+  const fileIds = files.map(({ id }) => id);
+
+  if (id === "root") {
+    return { id, subDirectoryIds, fileIds };
+  } else if (directory) {
+    return { id, name: directory.name, subDirectoryIds, fileIds };
+  }
+  return undefined;
+};
+
+export const getDirectoryInfo = (id: DirectoryId, masterKey: CryptoKey) => {
+  return createQuery<DirectoryInfo>({
+    queryKey: ["directory", id],
+    queryFn: async ({ client, signal }) => {
+      if (!client.getQueryData(["directory", id])) {
+        const initialInfo = await getInitialDirectoryInfo(id);
+        if (initialInfo) {
+          setTimeout(() => client.invalidateQueries({ queryKey: ["directory", id] }), 0);
+          return initialInfo;
+        }
+      }
+
+      const res = await callGetApi(`/api/directory/${id}`, { signal }); // TODO: 404
+      const {
+        metadata,
+        subDirectories: subDirectoryIds,
+        files: fileIds,
+      }: DirectoryInfoResponse = await res.json();
+
+      if (id === "root") {
+        return { id, subDirectoryIds, fileIds };
+      } else {
+        const { dataKey } = await unwrapDataKey(metadata!.dek, masterKey);
+        const name = await decryptString(metadata!.name, metadata!.nameIv, dataKey);
+        await storeDirectoryInfo({ id, parentId: metadata!.parent, name });
+        return {
+          id,
+          dataKey,
+          dataKeyVersion: new Date(metadata!.dekVersion),
+          name,
+          subDirectoryIds,
+          fileIds,
+        };
+      }
+    },
+    staleTime: Infinity,
+  });
+};
+
+export type DirectoryInfoStore = ReturnType<typeof getDirectoryInfo>;
+
+export const useDirectoryCreation = (parentId: DirectoryId, masterKey: MasterKey) => {
+  const queryClient = useQueryClient();
+  return createMutation<void, Error, { name: string }, { tempId: number }>({
+    mutationFn: async ({ name }) => {
+      const { dataKey, dataKeyVersion } = await generateDataKey();
+      const nameEncrypted = await encryptString(name, dataKey);
+
+      const res = await callPostApi<DirectoryCreateRequest>(`/api/directory/create`, {
+        parent: parentId,
+        mekVersion: masterKey.version,
+        dek: await wrapDataKey(dataKey, masterKey.key),
+        dekVersion: dataKeyVersion.toISOString(),
+        name: nameEncrypted.ciphertext,
+        nameIv: nameEncrypted.iv,
+      });
+      if (!res.ok) throw new Error("Failed to create directory");
+
+      const { directory: id }: DirectoryCreateResponse = await res.json();
+      queryClient.setQueryData<DirectoryInfo>(["directory", id], {
+        id,
+        name,
+        dataKey,
+        dataKeyVersion,
+        subDirectoryIds: [],
+        fileIds: [],
+      });
+      await storeDirectoryInfo({ id, parentId, name });
+    },
+    onMutate: async ({ name }) => {
+      const tempId = temporaryIdCounter--;
+      queryClient.setQueryData<DirectoryInfo>(["directory", tempId], {
+        id: tempId,
+        name,
+        subDirectoryIds: [],
+        fileIds: [],
+      });
+
+      await queryClient.cancelQueries({ queryKey: ["directory", parentId] });
+      queryClient.setQueryData<DirectoryInfo>(["directory", parentId], (prevParentInfo) => {
+        if (!prevParentInfo) return undefined;
+        return {
+          ...prevParentInfo,
+          subDirectoryIds: [...prevParentInfo.subDirectoryIds, tempId],
+        };
+      });
+
+      return { tempId };
+    },
+    onError: (_error, _variables, context) => {
+      if (context) {
+        queryClient.setQueryData<DirectoryInfo>(["directory", parentId], (prevParentInfo) => {
+          if (!prevParentInfo) return undefined;
+          return {
+            ...prevParentInfo,
+            subDirectoryIds: prevParentInfo.subDirectoryIds.filter((id) => id !== context.tempId),
+          };
+        });
+      }
+    },
+    onSettled: () => {
+      queryClient.invalidateQueries({ queryKey: ["directory", parentId] });
+    },
+  });
+};
+
+export const useDirectoryRename = () => {
+  const queryClient = useQueryClient();
+  return createMutation<
+    void,
+    Error,
+    {
+      id: number;
+      dataKey: CryptoKey;
+      dataKeyVersion: Date;
+      newName: string;
+    },
+    { oldName: string | undefined }
+  >({
+    mutationFn: async ({ id, dataKey, dataKeyVersion, newName }) => {
+      const newNameEncrypted = await encryptString(newName, dataKey);
+      const res = await callPostApi<DirectoryRenameRequest>(`/api/directory/${id}/rename`, {
+        dekVersion: dataKeyVersion.toISOString(),
+        name: newNameEncrypted.ciphertext,
+        nameIv: newNameEncrypted.iv,
+      });
+      if (!res.ok) throw new Error("Failed to rename directory");
+
+      await updateDirectoryInfo(id, { name: newName });
+    },
+    onMutate: async ({ id, newName }) => {
+      await queryClient.cancelQueries({ queryKey: ["directory", id] });
+
+      const prevInfo = queryClient.getQueryData<SubDirectoryInfo>(["directory", id]);
+      if (prevInfo) {
+        queryClient.setQueryData<DirectoryInfo>(["directory", id], {
+          ...prevInfo,
+          name: newName,
+        });
+      }
+
+      return { oldName: prevInfo?.name };
+    },
+    onError: (_error, { id }, context) => {
+      if (context?.oldName) {
+        queryClient.setQueryData<SubDirectoryInfo>(["directory", id], (prevInfo) => {
+          if (!prevInfo) return undefined;
+          return { ...prevInfo, name: context.oldName! };
+        });
+      }
+    },
+    onSettled: (_data, _error, { id }) => {
+      queryClient.invalidateQueries({ queryKey: ["directory", id] });
+    },
+  });
+};
+
+export const useDirectoryDeletion = (parentId: DirectoryId) => {
+  const queryClient = useQueryClient();
+  return createMutation<{ deletedFiles: number[] }, Error, { id: number }, {}>({
+    mutationFn: async ({ id }) => {
+      const res = await callPostApi(`/api/directory/${id}/delete`);
+      if (!res.ok) throw new Error("Failed to delete directory");
+
+      const { deletedDirectories, deletedFiles }: DirectoryDeleteResponse = await res.json();
+      await Promise.all([
+        ...deletedDirectories.map(deleteDirectoryInfo),
+        ...deletedFiles.map(deleteFileInfo),
+      ]);
+
+      return { deletedFiles };
+    },
+    onMutate: async ({ id }) => {
+      await queryClient.cancelQueries({ queryKey: ["directory", parentId] });
+      queryClient.setQueryData<DirectoryInfo>(["directory", parentId], (prevParentInfo) => {
+        if (!prevParentInfo) return undefined;
+        return {
+          ...prevParentInfo,
+          subDirectoryIds: prevParentInfo.subDirectoryIds.filter(
+            (subDirectoryId) => subDirectoryId !== id,
+          ),
+        };
+      });
+      return {};
+    },
+    onError: (_error, { id }, context) => {
+      if (context) {
+        queryClient.setQueryData<DirectoryInfo>(["directory", parentId], (prevParentInfo) => {
+          if (!prevParentInfo) return undefined;
+          return {
+            ...prevParentInfo,
+            subDirectoryIds: [...prevParentInfo.subDirectoryIds, id],
+          };
+        });
+      }
+    },
+    onSettled: () => {
+      queryClient.invalidateQueries({ queryKey: ["directory", parentId] });
+    },
+  });
+};

src/lib/modules/filesystem2/file.ts

@@ -0,0 +1,230 @@
+import { useQueryClient, createQuery, createMutation } from "@tanstack/svelte-query";
+import { callGetApi, callPostApi } from "$lib/hooks";
+import {
+  getFileInfo as getFileInfoFromIndexedDB,
+  storeFileInfo,
+  updateFileInfo,
+  deleteFileInfo,
+  type DirectoryId,
+} from "$lib/indexedDB";
+import { unwrapDataKey, encryptString, decryptString } from "$lib/modules/crypto";
+import { uploadFile } from "$lib/modules/file";
+import type { FileInfoResponse, FileRenameRequest } from "$lib/server/schemas";
+import type { MasterKey, HmacSecret } from "$lib/stores";
+import type { DirectoryInfo } from "./directory";
+
+export interface FileInfo {
+  id: number;
+  dataKey?: CryptoKey;
+  dataKeyVersion?: Date;
+  contentType: string;
+  contentIv?: string;
+  name: string;
+  createdAt?: Date;
+  lastModifiedAt: Date;
+  categoryIds: number[];
+}
+
+const decryptDate = async (ciphertext: string, iv: string, dataKey: CryptoKey) => {
+  return new Date(parseInt(await decryptString(ciphertext, iv, dataKey), 10));
+};
+
+export const getFileInfo = (id: number, masterKey: CryptoKey) => {
+  return createQuery<FileInfo>({
+    queryKey: ["file", id],
+    queryFn: async ({ client, signal }) => {
+      if (!client.getQueryData(["file", id])) {
+        const initialInfo = await getFileInfoFromIndexedDB(id);
+        if (initialInfo) {
+          setTimeout(() => client.invalidateQueries({ queryKey: ["file", id] }), 0);
+          return initialInfo;
+        }
+      }
+
+      const res = await callGetApi(`/api/file/${id}`, { signal }); // TODO: 404
+      const metadata: FileInfoResponse = await res.json();
+
+      const { dataKey } = await unwrapDataKey(metadata.dek, masterKey);
+      const name = await decryptString(metadata.name, metadata.nameIv, dataKey);
+      const createdAt =
+        metadata.createdAt && metadata.createdAtIv
+          ? await decryptDate(metadata.createdAt, metadata.createdAtIv, dataKey)
+          : undefined;
+      const lastModifiedAt = await decryptDate(
+        metadata.lastModifiedAt,
+        metadata.lastModifiedAtIv,
+        dataKey,
+      );
+
+      await storeFileInfo({
+        id,
+        parentId: metadata.parent,
+        name,
+        contentType: metadata.contentType,
+        createdAt,
+        lastModifiedAt,
+        categoryIds: metadata.categories,
+      });
+      return {
+        id,
+        dataKey,
+        dataKeyVersion: new Date(metadata.dekVersion),
+        contentType: metadata.contentType,
+        contentIv: metadata.contentIv,
+        name,
+        createdAt,
+        lastModifiedAt,
+        categoryIds: metadata.categories,
+      };
+    },
+    staleTime: Infinity,
+  });
+};
+
+export type FileInfoStore = ReturnType<typeof getFileInfo>;
+
+export const useFileUpload = (
+  parentId: DirectoryId,
+  masterKey: MasterKey,
+  hmacSecret: HmacSecret,
+) => {
+  const queryClient = useQueryClient();
+  return createMutation<
+    { fileId: number; fileBuffer: ArrayBuffer; thumbnailBuffer?: ArrayBuffer },
+    Error,
+    { file: File; onDuplicate: () => Promise<boolean> },
+    { tempId: number }
+  >({
+    mutationFn: async ({ file, onDuplicate }) => {
+      const res = await uploadFile(file, parentId, hmacSecret, masterKey, onDuplicate);
+      if (!res) throw new Error("Failed to upload file");
+
+      queryClient.setQueryData<FileInfo>(["file", res.fileId], {
+        id: res.fileId,
+        dataKey: res.fileDataKey,
+        dataKeyVersion: res.fileDataKeyVersion,
+        contentType: res.fileType,
+        contentIv: res.fileEncryptedIv,
+        name: file.name,
+        createdAt: res.fileCreatedAt,
+        lastModifiedAt: new Date(file.lastModified),
+        categoryIds: [],
+      });
+      await storeFileInfo({
+        id: res.fileId,
+        parentId,
+        name: file.name,
+        contentType: res.fileType,
+        createdAt: res.fileCreatedAt,
+        lastModifiedAt: new Date(file.lastModified),
+        categoryIds: [],
+      });
+      return {
+        fileId: res.fileId,
+        fileBuffer: res.fileBuffer,
+        thumbnailBuffer: res.thumbnailBuffer,
+      };
+    },
+    onSuccess: async ({ fileId }) => {
+      await queryClient.cancelQueries({ queryKey: ["directory", parentId] });
+      queryClient.setQueryData<DirectoryInfo>(["directory", parentId], (prevParentInfo) => {
+        if (!prevParentInfo) return undefined;
+        return {
+          ...prevParentInfo,
+          fileIds: [...prevParentInfo.fileIds, fileId],
+        };
+      });
+    },
+    onSettled: () => {
+      queryClient.invalidateQueries({ queryKey: ["directory", parentId] });
+    },
+  });
+};
+
+export const useFileRename = () => {
+  const queryClient = useQueryClient();
+  return createMutation<
+    void,
+    Error,
+    {
+      id: number;
+      dataKey: CryptoKey;
+      dataKeyVersion: Date;
+      newName: string;
+    },
+    { oldName: string | undefined }
+  >({
+    mutationFn: async ({ id, dataKey, dataKeyVersion, newName }) => {
+      const newNameEncrypted = await encryptString(newName, dataKey);
+      const res = await callPostApi<FileRenameRequest>(`/api/file/${id}/rename`, {
+        dekVersion: dataKeyVersion.toISOString(),
+        name: newNameEncrypted.ciphertext,
+        nameIv: newNameEncrypted.iv,
+      });
+      if (!res.ok) throw new Error("Failed to rename file");
+
+      await updateFileInfo(id, { name: newName });
+    },
+    onMutate: async ({ id, newName }) => {
+      await queryClient.cancelQueries({ queryKey: ["file", id] });
+
+      const prevInfo = queryClient.getQueryData<FileInfo>(["file", id]);
+      if (prevInfo) {
+        queryClient.setQueryData<FileInfo>(["file", id], {
+          ...prevInfo,
+          name: newName,
+        });
+      }
+
+      return { oldName: prevInfo?.name };
+    },
+    onError: (_error, { id }, context) => {
+      if (context?.oldName) {
+        queryClient.setQueryData<FileInfo>(["file", id], (prevInfo) => {
+          if (!prevInfo) return undefined;
+          return { ...prevInfo, name: context.oldName! };
+        });
+      }
+    },
+    onSettled: (_data, _error, { id }) => {
+      queryClient.invalidateQueries({ queryKey: ["file", id] });
+    },
+  });
+};
+
+export const useFileDeletion = (parentId: DirectoryId) => {
+  const queryClient = useQueryClient();
+  return createMutation<void, Error, { id: number }, {}>({
+    mutationFn: async ({ id }) => {
+      const res = await callPostApi(`/api/file/${id}/delete`);
+      if (!res.ok) throw new Error("Failed to delete file");
+
+      await deleteFileInfo(id);
+    },
+    onMutate: async ({ id }) => {
+      await queryClient.cancelQueries({ queryKey: ["directory", parentId] });
+      queryClient.setQueryData<DirectoryInfo>(["directory", parentId], (prevParentInfo) => {
+        if (!prevParentInfo) return undefined;
+        return {
+          ...prevParentInfo,
+          fileIds: prevParentInfo.fileIds.filter((fileId) => fileId !== id),
+        };
+      });
+      return {};
+    },
+    onError: (_error, { id }, context) => {
+      if (context) {
+        queryClient.setQueryData<DirectoryInfo>(["directory", parentId], (prevParentInfo) => {
+          if (!prevParentInfo) return undefined;
+          return {
+            ...prevParentInfo,
+            fileIds: [...prevParentInfo.fileIds, id],
+          };
+        });
+      }
+    },
+    onSettled: () => {
+      queryClient.invalidateQueries({ queryKey: ["directory", parentId] });
+    },
+  });
+};

src/lib/modules/filesystem2/index.ts

@@ -0,0 +1,3 @@
+export * from "./category";
+export * from "./directory";
+export * from "./file";

src/lib/server/db/category.ts

@@ -17,7 +17,7 @@ interface Category {
 export type NewCategory = Omit<Category, "id">;
 
 export const registerCategory = async (params: NewCategory) => {
-  await db.transaction().execute(async (trx) => {
+  return await db.transaction().execute(async (trx) => {
     const mek = await trx
       .selectFrom("master_encryption_key")
       .select("version")
@@ -51,6 +51,7 @@ export const registerCategory = async (params: NewCategory) => {
         new_name: params.encName,
       })
       .execute();
+    return { id: categoryId };
   });
 };
 

src/lib/server/db/file.ts

@@ -39,7 +39,7 @@ interface File {
 export type NewFile = Omit<File, "id">;
 
 export const registerDirectory = async (params: NewDirectory) => {
-  await db.transaction().execute(async (trx) => {
+  return await db.transaction().execute(async (trx) => {
     const mek = await trx
       .selectFrom("master_encryption_key")
       .select("version")
@@ -73,6 +73,7 @@ export const registerDirectory = async (params: NewDirectory) => {
         new_name: params.encName,
       })
       .execute();
+    return { id: directoryId };
   });
 };
 
@@ -180,7 +181,10 @@ export const unregisterDirectory = async (userId: number, directoryId: number) =
       };
       const unregisterDirectoryRecursively = async (
         directoryId: number,
-      ): Promise<{ id: number; path: string; thumbnailPath: string | null }[]> => {
+      ): Promise<{
+        subDirectories: { id: number }[];
+        files: { id: number; path: string; thumbnailPath: string | null }[];
+      }> => {
         const files = await unregisterFiles(directoryId);
         const subDirectories = await trx
           .selectFrom("directory")
@@ -188,7 +192,7 @@ export const unregisterDirectory = async (userId: number, directoryId: number) =
           .where("parent_id", "=", directoryId)
           .where("user_id", "=", userId)
           .execute();
-        const subDirectoryFilePaths = await Promise.all(
+        const subDirectoryEntries = await Promise.all(
           subDirectories.map(async ({ id }) => await unregisterDirectoryRecursively(id)),
         );
 
@@ -200,7 +204,12 @@ export const unregisterDirectory = async (userId: number, directoryId: number) =
         if (deleteRes.numDeletedRows === 0n) {
           throw new IntegrityError("Directory not found");
         }
-        return files.concat(...subDirectoryFilePaths);
+        return {
+          subDirectories: subDirectoryEntries
+            .flatMap(({ subDirectories }) => subDirectories)
+            .concat(subDirectories),
+          files: subDirectoryEntries.flatMap(({ files }) => files).concat(files),
+        };
       };
       return await unregisterDirectoryRecursively(directoryId);
     });

src/lib/server/schemas/category.ts

@@ -53,3 +53,8 @@ export const categoryCreateRequest = z.object({
   nameIv: z.string().base64().nonempty(),
 });
 export type CategoryCreateRequest = z.input<typeof categoryCreateRequest>;
+
+export const categoryCreateResponse = z.object({
+  category: z.number().int().positive(),
+});
+export type CategoryCreateResponse = z.output<typeof categoryCreateResponse>;

src/lib/server/schemas/directory.ts

@@ -19,6 +19,7 @@ export const directoryInfoResponse = z.object({
 export type DirectoryInfoResponse = z.output<typeof directoryInfoResponse>;
 
 export const directoryDeleteResponse = z.object({
+  deletedDirectories: z.number().int().positive().array(),
   deletedFiles: z.number().int().positive().array(),
 });
 export type DirectoryDeleteResponse = z.output<typeof directoryDeleteResponse>;
@@ -39,3 +40,8 @@ export const directoryCreateRequest = z.object({
   nameIv: z.string().base64().nonempty(),
 });
 export type DirectoryCreateRequest = z.input<typeof directoryCreateRequest>;
+
+export const directoryCreateResponse = z.object({
+  directory: z.number().int().positive(),
+});
+export type DirectoryCreateResponse = z.output<typeof directoryCreateResponse>;

src/lib/server/services/category.ts

@@ -123,7 +123,8 @@ export const createCategory = async (params: NewCategory) => {
   }
 
   try {
-    await registerCategory(params);
+    const { id } = await registerCategory(params);
+    return { id };
   } catch (e) {
     if (e instanceof IntegrityError && e.message === "Inactive MEK version") {
       error(400, "Inactive MEK version");

src/lib/server/services/directory.ts

@@ -42,8 +42,9 @@ const safeUnlink = async (path: string | null) => {
 
 export const deleteDirectory = async (userId: number, directoryId: number) => {
   try {
-    const files = await unregisterDirectory(userId, directoryId);
+    const { subDirectories, files } = await unregisterDirectory(userId, directoryId);
     return {
+      directories: [...subDirectories.map(({ id }) => id), directoryId],
       files: files.map(({ id, path, thumbnailPath }) => {
         safeUnlink(path); // Intended
         safeUnlink(thumbnailPath); // Intended
@@ -86,7 +87,8 @@ export const createDirectory = async (params: NewDirectory) => {
   }
 
   try {
-    await registerDirectory(params);
+    const { id } = await registerDirectory(params);
+    return { id };
   } catch (e) {
     if (e instanceof IntegrityError && e.message === "Inactive MEK version") {
       error(400, "Invalid MEK version");

src/routes/(fullscreen)/file/[id]/+page.svelte

@@ -5,12 +5,8 @@
   import { goto } from "$app/navigation";
   import { FullscreenDiv } from "$lib/components/atoms";
   import { Categories, IconEntryButton, TopBar } from "$lib/components/molecules";
-  import {
+  import { getCategoryInfo, type CategoryInfo } from "$lib/modules/filesystem2";
-    getFileInfo,
+  import { getFileInfo } from "$lib/modules/filesystem2";
-    getCategoryInfo,
-    type FileInfo,
-    type CategoryInfo,
-  } from "$lib/modules/filesystem";
   import { captureVideoThumbnail } from "$lib/modules/thumbnail";
   import { fileDownloadStatusStore, isFileDownloading, masterKeyStore } from "$lib/stores";
   import AddToCategoryBottomSheet from "./AddToCategoryBottomSheet.svelte";
@@ -28,8 +24,7 @@
 
   let { data } = $props();
 
-  let info: Writable<FileInfo | null> | undefined = $state();
+  let info = $derived(getFileInfo(data.id, $masterKeyStore?.get(1)?.key!));
-  let categories: Writable<CategoryInfo | null>[] = $state([]);
 
   let isAddToCategoryBottomSheetOpen = $state(false);
 
@@ -85,19 +80,14 @@
   };
 
   $effect(() => {
-    info = getFileInfo(data.id, $masterKeyStore?.get(1)?.key!);
+    data.id;
     isDownloadRequested = false;
     viewerType = undefined;
   });
 
   $effect(() => {
-    categories =
+    if ($info.data?.dataKey && $info.data?.contentIv) {
-      $info?.categoryIds.map((id) => getCategoryInfo(id, $masterKeyStore?.get(1)?.key!)) ?? [];
+      const contentType = $info.data.contentType;
-  });
-
-  $effect(() => {
-    if ($info && $info.dataKey && $info.contentIv) {
-      const contentType = $info.contentType;
       if (contentType.startsWith("image")) {
         viewerType = "image";
       } else if (contentType.startsWith("video")) {
@@ -107,21 +97,23 @@
       untrack(() => {
         if (!downloadStatus && !isDownloadRequested) {
           isDownloadRequested = true;
-          requestFileDownload(data.id, $info.contentIv!, $info.dataKey!).then(async (buffer) => {
+          requestFileDownload(data.id, $info.data.contentIv!, $info.data.dataKey!).then(
+            async (buffer) => {
               const blob = await updateViewer(buffer, contentType);
               if (!viewerType) {
-              FileSaver.saveAs(blob, $info.name);
+                FileSaver.saveAs(blob, $info.data.name);
               }
-          });
+            },
+          );
         }
       });
     }
   });
 
   $effect(() => {
-    if ($info && $downloadStatus?.status === "decrypted") {
+    if ($info.status === "success" && $downloadStatus?.status === "decrypted") {
       untrack(
-        () => !isDownloadRequested && updateViewer($downloadStatus.result!, $info.contentType),
+        () => !isDownloadRequested && updateViewer($downloadStatus.result!, $info.data.contentType),
       );
     }
   });
@@ -133,11 +125,11 @@
   <title>파일</title>
 </svelte:head>
 
-<TopBar title={$info?.name} />
+<TopBar title={$info.data?.name} />
 <FullscreenDiv>
   <div class="space-y-4 pb-4">
     <DownloadStatus status={downloadStatus} />
-    {#if $info && viewerType}
+    {#if $info.status === "success" && viewerType}
       <div class="flex w-full justify-center">
         {#snippet viewerLoading(message: string)}
           <p class="text-gray-500">{message}</p>
@@ -145,7 +137,7 @@
 
         {#if viewerType === "image"}
           {#if fileBlobUrl}
-            <img src={fileBlobUrl} alt={$info.name} onerror={convertHeicToJpeg} />
+            <img src={fileBlobUrl} alt={$info.data.name} onerror={convertHeicToJpeg} />
           {:else}
             {@render viewerLoading("이미지를 불러오고 있어요.")}
           {/if}
@@ -156,7 +148,7 @@
               <video bind:this={videoElement} src={fileBlobUrl} controls muted></video>
               <IconEntryButton
                 icon={IconCamera}
-                onclick={() => updateThumbnail($info.dataKey!, $info.dataKeyVersion!)}
+                onclick={() => updateThumbnail($info.data.dataKey!, $info.data.dataKeyVersion!)}
                 class="w-full"
               >
                 이 장면을 썸네일로 설정하기
@@ -172,7 +164,7 @@
       <p class="text-lg font-bold">카테고리</p>
       <div class="space-y-1">
         <Categories
-          {categories}
+          categoryIds={$info.data?.categoryIds ?? []}
           categoryMenuIcon={IconClose}
           onCategoryClick={({ id }) => goto(`/category/${id}`)}
           onCategoryMenuClick={({ id }) => removeFromCategory(id)}

src/routes/(fullscreen)/file/[id]/AddToCategoryBottomSheet.svelte

@@ -1,9 +1,8 @@
 <script lang="ts">
-  import type { Writable } from "svelte/store";
   import { BottomDiv, BottomSheet, Button, FullscreenDiv } from "$lib/components/atoms";
   import { SubCategories } from "$lib/components/molecules";
   import { CategoryCreateModal } from "$lib/components/organisms";
-  import { getCategoryInfo, type CategoryInfo } from "$lib/modules/filesystem";
+  import { getCategoryInfo, type CategoryInfoStore } from "$lib/modules/filesystem2";
   import { masterKeyStore } from "$lib/stores";
   import { requestCategoryCreation } from "./service";
 
@@ -14,7 +13,7 @@
 
   let { onAddToCategoryClick, isOpen = $bindable() }: Props = $props();
 
-  let category: Writable<CategoryInfo | null> | undefined = $state();
+  let category: CategoryInfoStore | undefined = $state();
 
   let isCategoryCreateModalOpen = $state(false);
 
@@ -25,20 +24,20 @@
   });
 </script>
 
-{#if $category}
+{#if $category?.status === "success"}
   <BottomSheet bind:isOpen class="flex flex-col">
     <FullscreenDiv>
       <SubCategories
         class="py-4"
-        info={$category}
+        info={$category.data}
         onSubCategoryClick={({ id }) =>
           (category = getCategoryInfo(id, $masterKeyStore?.get(1)?.key!))}
         onSubCategoryCreateClick={() => (isCategoryCreateModalOpen = true)}
         subCategoryCreatePosition="top"
       />
-      {#if $category.id !== "root"}
+      {#if $category.data.id !== "root"}
         <BottomDiv>
-          <Button onclick={() => onAddToCategoryClick($category.id)} class="w-full">
+          <Button onclick={() => onAddToCategoryClick($category.data.id as number)} class="w-full">
             이 카테고리에 추가하기
           </Button>
         </BottomDiv>
@@ -50,8 +49,8 @@
 <CategoryCreateModal
   bind:isOpen={isCategoryCreateModalOpen}
   onCreateClick={async (name: string) => {
-    if (await requestCategoryCreation(name, $category!.id, $masterKeyStore?.get(1)!)) {
+    if (await requestCategoryCreation(name, $category!.data!.id, $masterKeyStore?.get(1)!)) {
-      category = getCategoryInfo($category!.id, $masterKeyStore?.get(1)?.key!); // TODO: FIXME
+      category = getCategoryInfo($category!.data!.id, $masterKeyStore?.get(1)?.key!); // TODO: FIXME
       return true;
     }
     return false;

src/routes/(fullscreen)/file/downloads/File.svelte

@@ -1,6 +1,6 @@
 <script lang="ts">
   import { get, type Writable } from "svelte/store";
-  import { getFileInfo, type FileInfo } from "$lib/modules/filesystem";
+  import { getFileInfo } from "$lib/modules/filesystem2";
   import { formatNetworkSpeed } from "$lib/modules/util";
   import { masterKeyStore, type FileDownloadStatus } from "$lib/stores";
 
@@ -17,14 +17,10 @@
 
   let { status }: Props = $props();
 
-  let fileInfo: Writable<FileInfo | null> | undefined = $state();
+  let fileInfo = $derived(getFileInfo(get(status).id, $masterKeyStore?.get(1)?.key!));
-
-  $effect(() => {
-    fileInfo = getFileInfo(get(status).id, $masterKeyStore?.get(1)?.key!);
-  });
 </script>
 
-{#if $fileInfo}
+{#if $fileInfo.status === "success"}
   <div class="flex h-14 items-center gap-x-4 p-2">
     <div class="flex-shrink-0 text-lg text-gray-600">
       {#if $status.status === "download-pending"}
@@ -42,8 +38,8 @@
       {/if}
     </div>
     <div class="flex-grow overflow-hidden">
-      <p title={$fileInfo.name} class="truncate font-medium">
+      <p title={$fileInfo.data.name} class="truncate font-medium">
-        {$fileInfo.name}
+        {$fileInfo.data.name}
       </p>
       <p class="text-xs text-gray-800">
         {#if $status.status === "download-pending"}

src/routes/(fullscreen)/settings/cache/+page.svelte

@@ -1,18 +1,17 @@
 <script lang="ts">
   import { onMount } from "svelte";
-  import type { Writable } from "svelte/store";
   import { FullscreenDiv } from "$lib/components/atoms";
   import { TopBar } from "$lib/components/molecules";
   import type { FileCacheIndex } from "$lib/indexedDB";
   import { getFileCacheIndex, deleteFileCache as doDeleteFileCache } from "$lib/modules/file";
-  import { getFileInfo, type FileInfo } from "$lib/modules/filesystem";
+  import { getFileInfo, type FileInfoStore } from "$lib/modules/filesystem2";
   import { formatFileSize } from "$lib/modules/util";
   import { masterKeyStore } from "$lib/stores";
   import File from "./File.svelte";
 
   interface FileCache {
     index: FileCacheIndex;
-    fileInfo: Writable<FileInfo | null>;
+    fileInfo: FileInfoStore;
   }
 
   let fileCache: FileCache[] | undefined = $state();

src/routes/(fullscreen)/settings/cache/File.svelte

@@ -1,7 +1,6 @@
 <script lang="ts">
-  import type { Writable } from "svelte/store";
   import type { FileCacheIndex } from "$lib/indexedDB";
-  import type { FileInfo } from "$lib/modules/filesystem";
+  import type { FileInfoStore } from "$lib/modules/filesystem2";
   import { formatDate, formatFileSize } from "$lib/modules/util";
 
   import IconDraft from "~icons/material-symbols/draft";
@@ -10,7 +9,7 @@
 
   interface Props {
     index: FileCacheIndex;
-    info: Writable<FileInfo | null>;
+    info: FileInfoStore;
     onDeleteClick: (fileId: number) => void;
   }
 
@@ -28,8 +27,8 @@
     </div>
   {/if}
   <div class="flex-grow overflow-hidden">
-    {#if $info}
+    {#if $info.status === "success"}
-      <p title={$info.name} class="truncate font-medium">{$info.name}</p>
+      <p title={$info.data.name} class="truncate font-medium">{$info.data.name}</p>
     {:else}
       <p class="font-medium">삭제된 파일</p>
     {/if}

src/routes/(fullscreen)/settings/thumbnail/+page.svelte

@@ -5,7 +5,7 @@
   import { BottomDiv, Button, FullscreenDiv } from "$lib/components/atoms";
   import { IconEntryButton, TopBar } from "$lib/components/molecules";
   import { deleteAllFileThumbnailCaches } from "$lib/modules/file";
-  import { getFileInfo } from "$lib/modules/filesystem";
+  import { getFileInfo } from "$lib/modules/filesystem2";
   import { masterKeyStore } from "$lib/stores";
   import File from "./File.svelte";
   import {
@@ -21,8 +21,8 @@
   const generateAllThumbnails = () => {
     persistentStates.files.forEach(({ info }) => {
       const fileInfo = get(info);
-      if (fileInfo) {
+      if (fileInfo.data) {
-        requestThumbnailGeneration(fileInfo);
+        requestThumbnailGeneration(fileInfo.data);
       }
     });
   };

src/routes/(fullscreen)/settings/thumbnail/+page.ts

@@ -4,7 +4,7 @@ import type { MissingThumbnailFileScanResponse } from "$lib/server/schemas";
 import type { PageLoad } from "./$types";
 
 export const load: PageLoad = async ({ fetch }) => {
-  const res = await callPostApi("/api/file/scanMissingThumbnails", undefined, fetch);
+  const res = await callPostApi("/api/file/scanMissingThumbnails", undefined, { fetch });
   if (!res.ok) {
     error(500, "Internal server error");
   }

src/routes/(fullscreen)/settings/thumbnail/File.svelte

@@ -13,14 +13,14 @@
   import type { Writable } from "svelte/store";
   import { ActionEntryButton } from "$lib/components/atoms";
   import { DirectoryEntryLabel } from "$lib/components/molecules";
-  import type { FileInfo } from "$lib/modules/filesystem";
+  import type { FileInfo, FileInfoStore } from "$lib/modules/filesystem2";
   import { formatDateTime } from "$lib/modules/util";
   import type { GenerationStatus } from "./service.svelte";
 
   import IconCamera from "~icons/material-symbols/camera";
 
   interface Props {
-    info: Writable<FileInfo | null>;
+    info: FileInfoStore;
     onclick: (selectedFile: FileInfo) => void;
     onGenerateThumbnailClick: (selectedFile: FileInfo) => void;
     generationStatus?: Writable<GenerationStatus>;
@@ -29,18 +29,18 @@
   let { info, onclick, onGenerateThumbnailClick, generationStatus }: Props = $props();
 </script>
 
-{#if $info}
+{#if $info.status === "success"}
   <ActionEntryButton
     class="h-14"
-    onclick={() => onclick($info)}
+    onclick={() => onclick($info.data)}
     actionButtonIcon={!$generationStatus || $generationStatus === "error" ? IconCamera : undefined}
-    onActionButtonClick={() => onGenerateThumbnailClick($info)}
+    onActionButtonClick={() => onGenerateThumbnailClick($info.data)}
     actionButtonClass="text-gray-800"
   >
     {@const subtext =
       $generationStatus && $generationStatus !== "uploaded"
         ? subtexts[$generationStatus]
-        : formatDateTime($info.createdAt ?? $info.lastModifiedAt)}
+        : formatDateTime($info.data.createdAt ?? $info.data.lastModifiedAt)}
-    <DirectoryEntryLabel type="file" name={$info.name} {subtext} />
+    <DirectoryEntryLabel type="file" name={$info.data.name} {subtext} />
   </ActionEntryButton>
 {/if}

src/routes/(fullscreen)/settings/thumbnail/service.svelte.ts

@@ -2,7 +2,7 @@ import { limitFunction } from "p-limit";
 import { get, writable, type Writable } from "svelte/store";
 import { encryptData } from "$lib/modules/crypto";
 import { storeFileThumbnailCache } from "$lib/modules/file";
-import type { FileInfo } from "$lib/modules/filesystem";
+import type { FileInfo, FileInfoStore } from "$lib/modules/filesystem2";
 import { generateThumbnail as doGenerateThumbnail } from "$lib/modules/thumbnail";
 import { requestFileDownload, requestFileThumbnailUpload } from "$lib/services/file";
 
@@ -17,7 +17,7 @@ export type GenerationStatus =
 
 interface File {
   id: number;
-  info: Writable<FileInfo | null>;
+  info: FileInfoStore;
   status?: Writable<GenerationStatus>;
 }
 

src/routes/(main)/category/[[id]]/+page.svelte

@@ -1,9 +1,8 @@
 <script lang="ts">
-  import type { Writable } from "svelte/store";
   import { goto } from "$app/navigation";
   import { TopBar } from "$lib/components/molecules";
   import { Category, CategoryCreateModal } from "$lib/components/organisms";
-  import { getCategoryInfo, updateCategoryInfo, type CategoryInfo } from "$lib/modules/filesystem";
+  import { getCategoryInfo, useCategoryFileRecursionToggle } from "$lib/modules/filesystem2";
   import { masterKeyStore } from "$lib/stores";
   import CategoryDeleteModal from "./CategoryDeleteModal.svelte";
   import CategoryMenuBottomSheet from "./CategoryMenuBottomSheet.svelte";
@@ -19,9 +18,9 @@
   let { data } = $props();
   let context = createContext();
 
-  let info: Writable<CategoryInfo | null> | undefined = $state();
+  let info = $derived(getCategoryInfo(data.id, $masterKeyStore?.get(1)?.key!));
-
+  let toggleFileRecursion = useCategoryFileRecursionToggle();
-  let isFileRecursive: boolean | undefined = $state();
+  let isFileRecursive = $derived($info.data?.isFileRecursive);
 
   let isCategoryCreateModalOpen = $state(false);
   let isCategoryMenuBottomSheetOpen = $state(false);
@@ -29,19 +28,8 @@
   let isCategoryDeleteModalOpen = $state(false);
 
   $effect(() => {
-    info = getCategoryInfo(data.id, $masterKeyStore?.get(1)?.key!);
+    if (isFileRecursive !== undefined && $info.data?.isFileRecursive !== isFileRecursive) {
-    isFileRecursive = undefined;
+      $toggleFileRecursion.mutate({ id: data.id as number, isFileRecursive });
-  });
-
-  $effect(() => {
-    if ($info && isFileRecursive === undefined) {
-      isFileRecursive = $info.isFileRecursive ?? false;
-    }
-  });
-
-  $effect(() => {
-    if (data.id !== "root" && $info?.isFileRecursive !== isFileRecursive) {
-      updateCategoryInfo(data.id as number, { isFileRecursive });
     }
   });
 </script>
@@ -51,13 +39,13 @@
 </svelte:head>
 
 {#if data.id !== "root"}
-  <TopBar title={$info?.name} />
+  <TopBar title={$info.data?.name} />
 {/if}
 <div class="min-h-full bg-gray-100 pb-[5.5em]">
-  {#if $info && isFileRecursive !== undefined}
+  {#if $info.status === "success"}
     <Category
       bind:isFileRecursive
-      info={$info}
+      info={$info.data}
       onFileClick={({ id }) => goto(`/file/${id}`)}
       onFileRemoveClick={async ({ id }) => {
         await requestFileRemovalFromCategory(id, data.id as number);

src/routes/(main)/directory/[[id]]/+page.svelte

@@ -1,10 +1,23 @@
 <script lang="ts">
   import { onMount } from "svelte";
-  import type { Writable } from "svelte/store";
   import { goto } from "$app/navigation";
   import { FloatingButton } from "$lib/components/atoms";
   import { TopBar } from "$lib/components/molecules";
-  import { getDirectoryInfo, type DirectoryInfo } from "$lib/modules/filesystem";
+  import {
+    storeFileCache,
+    deleteFileCache,
+    storeFileThumbnailCache,
+    deleteFileThumbnailCache,
+  } from "$lib/modules/file";
+  import {
+    getDirectoryInfo,
+    useDirectoryCreation,
+    useDirectoryRename,
+    useDirectoryDeletion,
+    useFileUpload,
+    useFileRename,
+    useFileDeletion,
+  } from "$lib/modules/filesystem2";
   import { masterKeyStore, hmacSecretStore } from "$lib/stores";
   import DirectoryCreateModal from "./DirectoryCreateModal.svelte";
   import DirectoryEntries from "./DirectoryEntries";
@@ -15,21 +28,23 @@
   import EntryMenuBottomSheet from "./EntryMenuBottomSheet.svelte";
   import EntryRenameModal from "./EntryRenameModal.svelte";
   import UploadStatusCard from "./UploadStatusCard.svelte";
-  import {
+  import { createContext, requestHmacSecretDownload } from "./service.svelte";
-    createContext,
-    requestHmacSecretDownload,
-    requestDirectoryCreation,
-    requestFileUpload,
-    requestEntryRename,
-    requestEntryDeletion,
-  } from "./service.svelte";
 
   import IconAdd from "~icons/material-symbols/add";
 
   let { data } = $props();
   let context = createContext();
 
-  let info: Writable<DirectoryInfo | null> | undefined = $state();
+  let info = $derived(getDirectoryInfo(data.id, $masterKeyStore?.get(1)?.key!));
+  let requestDirectoryCreation = $derived(useDirectoryCreation(data.id, $masterKeyStore?.get(1)!));
+  let requestDirectoryRename = useDirectoryRename();
+  let requestDirectoryDeletion = $derived(useDirectoryDeletion(data.id));
+  let requestFileUpload = $derived(
+    useFileUpload(data.id, $masterKeyStore?.get(1)!, $hmacSecretStore?.get(1)!),
+  );
+  let requestFileRename = $derived(useFileRename());
+  let requestFileDeletion = $derived(useFileDeletion(data.id));
+
   let fileInput: HTMLInputElement | undefined = $state();
   let duplicatedFile: File | undefined = $state();
   let resolveForDuplicateFileModal: ((res: boolean) => void) | undefined = $state();
@@ -47,21 +62,24 @@
     if (!files || files.length === 0) return;
 
     for (const file of files) {
-      requestFileUpload(file, data.id, $hmacSecretStore?.get(1)!, $masterKeyStore?.get(1)!, () => {
+      $requestFileUpload
+        .mutateAsync({
+          file,
+          onDuplicate: () => {
             return new Promise((resolve) => {
               duplicatedFile = file;
               resolveForDuplicateFileModal = resolve;
               isDuplicateFileModalOpen = true;
             });
+          },
         })
         .then((res) => {
-          if (!res) return;
+          if (res) {
-          // TODO: FIXME
+            storeFileCache(res.fileId, res.fileBuffer); // Intended
-          info = getDirectoryInfo(data.id, $masterKeyStore?.get(1)?.key!);
+            if (res.thumbnailBuffer) {
-        })
+              storeFileThumbnailCache(res.fileId, res.thumbnailBuffer); // Intended
-        .catch((e: Error) => {
+            }
-          // TODO: FIXME
+          }
-          console.error(e);
         });
     }
 
@@ -73,10 +91,6 @@
       throw new Error("Failed to download hmac secrets");
     }
   });
-
-  $effect(() => {
-    info = getDirectoryInfo(data.id, $masterKeyStore?.get(1)?.key!);
-  });
 </script>
 
 <svelte:head>
@@ -87,17 +101,17 @@
 
 <div class="flex h-full flex-col">
   {#if data.id !== "root"}
-    <TopBar title={$info?.name} class="flex-shrink-0" />
+    <TopBar title={$info.data?.name} class="flex-shrink-0" />
   {/if}
-  {#if $info}
+  {#if $info.status === "success"}
     <div class={["flex flex-grow flex-col px-4 pb-4", data.id === "root" && "pt-4"]}>
       <div class="flex gap-x-2">
         <UploadStatusCard onclick={() => goto("/file/uploads")} />
         <DownloadStatusCard onclick={() => goto("/file/downloads")} />
       </div>
-      {#key $info}
+      {#key $info.data.id}
         <DirectoryEntries
-          info={$info}
+          info={$info.data}
           onEntryClick={({ type, id }) => goto(`/${type}/${id}`)}
           onEntryMenuClick={(entry) => {
             context.selectedEntry = entry;
@@ -130,11 +144,8 @@
 <DirectoryCreateModal
   bind:isOpen={isDirectoryCreateModalOpen}
   onCreateClick={async (name) => {
-    if (await requestDirectoryCreation(name, data.id, $masterKeyStore?.get(1)!)) {
+    $requestDirectoryCreation.mutate({ name });
-      info = getDirectoryInfo(data.id, $masterKeyStore?.get(1)?.key!); // TODO: FIXME
+    return true; // TODO
-      return true;
-    }
-    return false;
   }}
 />
 <DuplicateFileModal
@@ -164,20 +175,45 @@
 <EntryRenameModal
   bind:isOpen={isEntryRenameModalOpen}
   onRenameClick={async (newName: string) => {
-    if (await requestEntryRename(context.selectedEntry!, newName)) {
+    if (context.selectedEntry!.type === "directory") {
-      info = getDirectoryInfo(data.id, $masterKeyStore?.get(1)?.key!); // TODO: FIXME
+      $requestDirectoryRename.mutate({
-      return true;
+        id: context.selectedEntry!.id,
+        dataKey: context.selectedEntry!.dataKey,
+        dataKeyVersion: context.selectedEntry!.dataKeyVersion,
+        newName,
+      });
+      return true; // TODO
+    } else {
+      $requestFileRename.mutate({
+        id: context.selectedEntry!.id,
+        dataKey: context.selectedEntry!.dataKey,
+        dataKeyVersion: context.selectedEntry!.dataKeyVersion,
+        newName,
+      });
+      return true; // TODO
     }
-    return false;
   }}
 />
 <EntryDeleteModal
   bind:isOpen={isEntryDeleteModalOpen}
   onDeleteClick={async () => {
-    if (await requestEntryDeletion(context.selectedEntry!)) {
+    if (context.selectedEntry!.type === "directory") {
-      info = getDirectoryInfo(data.id, $masterKeyStore?.get(1)?.key!); // TODO: FIXME
+      const res = await $requestDirectoryDeletion.mutateAsync({ id: context.selectedEntry!.id });
-      return true;
+      if (!res) return false;
+      await Promise.all(
+        res.deletedFiles.flatMap((fileId) => [
+          deleteFileCache(fileId),
+          deleteFileThumbnailCache(fileId),
+        ]),
+      );
+      return true; // TODO
+    } else {
+      await $requestFileDeletion.mutateAsync({ id: context.selectedEntry!.id });
+      await Promise.all([
+        deleteFileCache(context.selectedEntry!.id),
+        deleteFileThumbnailCache(context.selectedEntry!.id),
+      ]);
+      return true; // TODO
     }
-    return false;
   }}
 />

src/routes/(main)/directory/[[id]]/DirectoryEntries/DirectoryEntries.svelte

@@ -1,12 +1,12 @@
 <script lang="ts">
-  import { untrack } from "svelte";
+  import { derived } from "svelte/store";
-  import { get, type Writable } from "svelte/store";
   import {
     getDirectoryInfo,
     getFileInfo,
     type DirectoryInfo,
+    type SubDirectoryInfo,
     type FileInfo,
-  } from "$lib/modules/filesystem";
+  } from "$lib/modules/filesystem2";
   import { SortBy, sortEntries } from "$lib/modules/util";
   import {
     fileUploadStatusStore,
@@ -30,88 +30,84 @@
 
   interface DirectoryEntry {
     name?: string;
-    info: Writable<DirectoryInfo | null>;
+    info: SubDirectoryInfo;
   }
 
   type FileEntry =
     | {
         type: "file";
         name?: string;
-        info: Writable<FileInfo | null>;
+        info: FileInfo;
       }
     | {
         type: "uploading-file";
         name: string;
-        info: Writable<FileUploadStatus>;
+        info: FileUploadStatus;
       };
 
-  let subDirectories: DirectoryEntry[] = $state([]);
+  let subDirectories = $derived(
-  let files: FileEntry[] = $state([]);
+    derived(
-
+      info.subDirectoryIds.map((id) => getDirectoryInfo(id, $masterKeyStore?.get(1)?.key!)),
-  $effect(() => {
+      (infos) => {
-    // TODO: Fix duplicated requests
+        const subDirectories = infos
-
+          .filter(($info) => $info.status === "success")
-    subDirectories = info.subDirectoryIds.map((id) => {
+          .map(
-      const info = getDirectoryInfo(id, $masterKeyStore?.get(1)?.key!);
+            ($info) =>
-      return { name: get(info)?.name, info };
+              ({
-    });
+                name: $info.data.name,
-    files = info.fileIds
+                info: $info.data as SubDirectoryInfo,
-      .map((id): FileEntry => {
+              }) satisfies DirectoryEntry,
-        const info = getFileInfo(id, $masterKeyStore?.get(1)?.key!);
-        return {
-          type: "file",
-          name: get(info)?.name,
-          info,
-        };
-      })
-      .concat(
-        $fileUploadStatusStore
-          .filter((statusStore) => {
-            const { parentId, status } = get(statusStore);
-            return parentId === info.id && isFileUploading(status);
-          })
-          .map((status) => ({
-            type: "uploading-file",
-            name: get(status).name,
-            info: status,
-          })),
           );
-
-    const sort = () => {
         sortEntries(subDirectories, sortBy);
-      sortEntries(files, sortBy);
+        return subDirectories;
-    };
+      },
-    return untrack(() => {
-      sort();
-
-      const unsubscribes = subDirectories
-        .map((subDirectory) =>
-          subDirectory.info.subscribe((value) => {
-            if (subDirectory.name === value?.name) return;
-            subDirectory.name = value?.name;
-            sort();
-          }),
-        )
-        .concat(
-          files.map((file) =>
-            file.info.subscribe((value) => {
-              if (file.name === value?.name) return;
-              file.name = value?.name;
-              sort();
-            }),
     ),
   );
-      return () => unsubscribes.forEach((unsubscribe) => unsubscribe());
+  let files = $derived(
-    });
+    derived(
-  });
+      info.fileIds.map((id) => getFileInfo(id, $masterKeyStore?.get(1)?.key!)),
+      (infos) =>
+        infos
+          .filter(($info) => $info.status === "success")
+          .map(
+            ($info) =>
+              ({
+                type: "file",
+                name: $info.data.name,
+                info: $info.data,
+              }) satisfies FileEntry,
+          ),
+    ),
+  );
+  let uploadingFiles = $derived(
+    derived($fileUploadStatusStore, (statuses) =>
+      statuses
+        .filter(({ parentId, status }) => parentId === info.id && isFileUploading(status))
+        .map(
+          ($status) =>
+            ({
+              type: "uploading-file",
+              name: $status.name,
+              info: $status,
+            }) satisfies FileEntry,
+        ),
+    ),
+  );
+  let everyFiles = $derived(
+    derived([files, uploadingFiles], ([$files, $uploadingFiles]) => {
+      const allFiles = [...$files, ...$uploadingFiles];
+      sortEntries(allFiles, sortBy);
+      return allFiles;
+    }),
+  );
 </script>
 
-{#if subDirectories.length + files.length > 0}
+{#if $subDirectories.length + $everyFiles.length > 0}
   <div class="space-y-1 pb-[4.5rem]">
-    {#each subDirectories as { info }}
+    {#each $subDirectories as { info }}
       <SubDirectory {info} onclick={onEntryClick} onOpenMenuClick={onEntryMenuClick} />
     {/each}
-    {#each files as file}
+    {#each $everyFiles as file}
       {#if file.type === "file"}
         <File info={file.info} onclick={onEntryClick} onOpenMenuClick={onEntryMenuClick} />
       {:else}

src/routes/(main)/directory/[[id]]/DirectoryEntries/File.svelte

@@ -1,8 +1,7 @@
 <script lang="ts">
-  import type { Writable } from "svelte/store";
   import { ActionEntryButton } from "$lib/components/atoms";
   import { DirectoryEntryLabel } from "$lib/components/molecules";
-  import type { FileInfo } from "$lib/modules/filesystem";
+  import type { FileInfo } from "$lib/modules/filesystem2";
   import { formatDateTime } from "$lib/modules/util";
   import { requestFileThumbnailDownload } from "./service";
   import type { SelectedEntry } from "../service.svelte";
@@ -10,7 +9,7 @@
   import IconMoreVert from "~icons/material-symbols/more-vert";
 
   interface Props {
-    info: Writable<FileInfo | null>;
+    info: FileInfo;
     onclick: (selectedEntry: SelectedEntry) => void;
     onOpenMenuClick: (selectedEntry: SelectedEntry) => void;
   }
@@ -20,22 +19,22 @@
   let thumbnail: string | undefined = $state();
 
   const openFile = () => {
-    const { id, dataKey, dataKeyVersion, name } = $info!;
+    const { id, dataKey, dataKeyVersion, name } = info;
     if (!dataKey || !dataKeyVersion) return; // TODO: Error handling
 
     onclick({ type: "file", id, dataKey, dataKeyVersion, name });
   };
 
   const openMenu = () => {
-    const { id, dataKey, dataKeyVersion, name } = $info!;
+    const { id, dataKey, dataKeyVersion, name } = info;
     if (!dataKey || !dataKeyVersion) return; // TODO: Error handling
 
     onOpenMenuClick({ type: "file", id, dataKey, dataKeyVersion, name });
   };
 
   $effect(() => {
-    if ($info?.dataKey) {
+    if (info.dataKey) {
-      requestFileThumbnailDownload($info.id, $info.dataKey)
+      requestFileThumbnailDownload(info.id, info.dataKey)
         .then((thumbnailUrl) => {
           thumbnail = thumbnailUrl ?? undefined;
         })
@@ -49,7 +48,6 @@
   });
 </script>
 
-{#if $info}
 <ActionEntryButton
   class="h-14"
   onclick={openFile}
@@ -59,8 +57,7 @@
   <DirectoryEntryLabel
     type="file"
     {thumbnail}
-      name={$info.name}
+    name={info.name}
-      subtext={formatDateTime($info.createdAt ?? $info.lastModifiedAt)}
+    subtext={formatDateTime(info.createdAt ?? info.lastModifiedAt)}
   />
 </ActionEntryButton>
-{/if}

src/routes/(main)/directory/[[id]]/DirectoryEntries/SubDirectory.svelte

@@ -1,16 +1,13 @@
 <script lang="ts">
-  import type { Writable } from "svelte/store";
   import { ActionEntryButton } from "$lib/components/atoms";
   import { DirectoryEntryLabel } from "$lib/components/molecules";
-  import type { DirectoryInfo } from "$lib/modules/filesystem";
+  import type { SubDirectoryInfo } from "$lib/modules/filesystem2";
   import type { SelectedEntry } from "../service.svelte";
 
   import IconMoreVert from "~icons/material-symbols/more-vert";
 
-  type SubDirectoryInfo = DirectoryInfo & { id: number };
-
   interface Props {
-    info: Writable<DirectoryInfo | null>;
+    info: SubDirectoryInfo;
     onclick: (selectedEntry: SelectedEntry) => void;
     onOpenMenuClick: (selectedEntry: SelectedEntry) => void;
   }
@@ -18,27 +15,25 @@
   let { info, onclick, onOpenMenuClick }: Props = $props();
 
   const openDirectory = () => {
-    const { id, dataKey, dataKeyVersion, name } = $info as SubDirectoryInfo;
+    const { id, dataKey, dataKeyVersion, name } = info;
     if (!dataKey || !dataKeyVersion) return; // TODO: Error handling
 
     onclick({ type: "directory", id, dataKey, dataKeyVersion, name });
   };
 
   const openMenu = () => {
-    const { id, dataKey, dataKeyVersion, name } = $info as SubDirectoryInfo;
+    const { id, dataKey, dataKeyVersion, name } = info;
     if (!dataKey || !dataKeyVersion) return; // TODO: Error handling
 
     onOpenMenuClick({ type: "directory", id, dataKey, dataKeyVersion, name });
   };
 </script>
 
-{#if $info}
 <ActionEntryButton
   class="h-14"
   onclick={openDirectory}
   actionButtonIcon={IconMoreVert}
   onActionButtonClick={openMenu}
 >
-    <DirectoryEntryLabel type="directory" name={$info.name!} />
+  <DirectoryEntryLabel type="directory" name={info.name} />
 </ActionEntryButton>
-{/if}

src/routes/(main)/directory/[[id]]/DirectoryEntries/UploadingFile.svelte

@@ -1,36 +1,35 @@
 <script lang="ts">
-  import type { Writable } from "svelte/store";
   import { formatNetworkSpeed } from "$lib/modules/util";
   import { isFileUploading, type FileUploadStatus } from "$lib/stores";
 
   import IconDraft from "~icons/material-symbols/draft";
 
   interface Props {
-    status: Writable<FileUploadStatus>;
+    status: FileUploadStatus;
   }
 
   let { status }: Props = $props();
 </script>
 
-{#if isFileUploading($status.status)}
+{#if isFileUploading(status.status)}
   <div class="flex h-14 gap-x-4 p-2">
     <div class="flex h-10 w-10 flex-shrink-0 items-center justify-center text-xl">
       <IconDraft class="text-gray-600" />
     </div>
     <div class="flex flex-grow flex-col overflow-hidden text-gray-800">
-      <p title={$status.name} class="truncate font-medium">
+      <p title={status.name} class="truncate font-medium">
-        {$status.name}
+        {status.name}
       </p>
       <p class="text-xs">
-        {#if $status.status === "encryption-pending"}
+        {#if status.status === "encryption-pending"}
           준비 중
-        {:else if $status.status === "encrypting"}
+        {:else if status.status === "encrypting"}
           암호화하는 중
-        {:else if $status.status === "upload-pending"}
+        {:else if status.status === "upload-pending"}
           업로드를 기다리는 중
-        {:else if $status.status === "uploading"}
+        {:else if status.status === "uploading"}
-          전송됨 {Math.floor(($status.progress ?? 0) * 100)}% ·
+          전송됨 {Math.floor((status.progress ?? 0) * 100)}% ·
-          {formatNetworkSpeed(($status.rate ?? 0) * 8)}
+          {formatNetworkSpeed((status.rate ?? 0) * 8)}
         {/if}
       </p>
     </div>

src/routes/(main)/menu/+page.ts

@@ -4,7 +4,7 @@ import type { UserInfoResponse } from "$lib/server/schemas";
 import type { PageLoad } from "./$types";
 
 export const load: PageLoad = async ({ fetch }) => {
-  const res = await callGetApi("/api/user", fetch);
+  const res = await callGetApi("/api/user", { fetch });
   if (!res.ok) {
     error(500, "Internal server error");
   }

src/routes/+layout.svelte

@@ -1,6 +1,8 @@
 <script lang="ts">
+  import { QueryClient, QueryClientProvider } from "@tanstack/svelte-query";
   import { onMount } from "svelte";
   import { get } from "svelte/store";
+  import { browser } from "$app/environment";
   import { goto as svelteGoto } from "$app/navigation";
   import {
     fileUploadStatusStore,
@@ -10,10 +12,19 @@
     clientKeyStore,
     masterKeyStore,
   } from "$lib/stores";
+
   import "../app.css";
 
   let { children } = $props();
 
+  const queryClient = new QueryClient({
+    defaultOptions: {
+      queries: {
+        enabled: browser,
+      },
+    },
+  });
+
   const protectFileUploadAndDownload = (e: BeforeUnloadEvent) => {
     if (
       $fileUploadStatusStore.some((status) => isFileUploading(get(status).status)) ||
@@ -24,6 +35,8 @@
   };
 
   onMount(async () => {
+    window.__TANSTACK_QUERY_CLIENT__ = queryClient;
+
     const goto = async (url: string) => {
       const whitelist = ["/auth/login", "/key", "/client/pending"];
       if (!whitelist.some((path) => location.pathname.startsWith(path))) {
@@ -43,4 +56,6 @@
 
 <svelte:window onbeforeunload={protectFileUploadAndDownload} />
 
+<QueryClientProvider client={queryClient}>
   {@render children()}
+</QueryClientProvider>

src/routes/api/category/create/+server.ts

@@ -1,6 +1,10 @@
-import { error, text } from "@sveltejs/kit";
+import { error, json } from "@sveltejs/kit";
 import { authorize } from "$lib/server/modules/auth";
-import { categoryCreateRequest } from "$lib/server/schemas";
+import {
+  categoryCreateRequest,
+  categoryCreateResponse,
+  type CategoryCreateResponse,
+} from "$lib/server/schemas";
 import { createCategory } from "$lib/server/services/category";
 import type { RequestHandler } from "./$types";
 
@@ -11,7 +15,7 @@ export const POST: RequestHandler = async ({ locals, request }) => {
   if (!zodRes.success) error(400, "Invalid request body");
   const { parent, mekVersion, dek, dekVersion, name, nameIv } = zodRes.data;
 
-  await createCategory({
+  const { id } = await createCategory({
     userId,
     parentId: parent,
     mekVersion,
@@ -19,5 +23,5 @@ export const POST: RequestHandler = async ({ locals, request }) => {
     dekVersion: new Date(dekVersion),
     encName: { ciphertext: name, iv: nameIv },
   });
-  return text("Category created", { headers: { "Content-Type": "text/plain" } });
+  return json(categoryCreateResponse.parse({ category: id } satisfies CategoryCreateResponse));
 };

src/routes/api/directory/[id]/delete/+server.ts

@@ -16,8 +16,11 @@ export const POST: RequestHandler = async ({ locals, params }) => {
   if (!zodRes.success) error(400, "Invalid path parameters");
   const { id } = zodRes.data;
 
-  const { files } = await deleteDirectory(userId, id);
+  const { directories, files } = await deleteDirectory(userId, id);
   return json(
-    directoryDeleteResponse.parse({ deletedFiles: files } satisfies DirectoryDeleteResponse),
+    directoryDeleteResponse.parse({
+      deletedDirectories: directories,
+      deletedFiles: files,
+    } satisfies DirectoryDeleteResponse),
   );
 };

src/routes/api/directory/create/+server.ts

@@ -1,6 +1,10 @@
-import { error, text } from "@sveltejs/kit";
+import { error, json } from "@sveltejs/kit";
 import { authorize } from "$lib/server/modules/auth";
-import { directoryCreateRequest } from "$lib/server/schemas";
+import {
+  directoryCreateRequest,
+  directoryCreateResponse,
+  type DirectoryCreateResponse,
+} from "$lib/server/schemas";
 import { createDirectory } from "$lib/server/services/directory";
 import type { RequestHandler } from "./$types";
 
@@ -11,7 +15,7 @@ export const POST: RequestHandler = async ({ locals, request }) => {
   if (!zodRes.success) error(400, "Invalid request body");
   const { parent, mekVersion, dek, dekVersion, name, nameIv } = zodRes.data;
 
-  await createDirectory({
+  const { id } = await createDirectory({
     userId,
     parentId: parent,
     mekVersion,
@@ -19,5 +23,5 @@ export const POST: RequestHandler = async ({ locals, request }) => {
     dekVersion: new Date(dekVersion),
     encName: { ciphertext: name, iv: nameIv },
   });
-  return text("Directory created", { headers: { "Content-Type": "text/plain" } });
+  return json(directoryCreateResponse.parse({ directory: id } satisfies DirectoryCreateResponse));
 };