Stage 7: configuration view — backend service, routers, tests, and frontend

- config_service.py: read/write jail config via asyncio.gather, global
  settings, in-process regex validation, log preview via _read_tail_lines
- server_service.py: read/write server settings, flush logs
- config router: 9 endpoints for jail/global config, regex-test,
  logpath management, log preview
- server router: GET/PUT settings, POST flush-logs
- models/config.py expanded with JailConfig, GlobalConfigUpdate,
  LogPreview* models
- 285 tests pass (68 new), ruff clean, mypy clean (44 files)
- Frontend: types/config.ts, api/config.ts, hooks/useConfig.ts,
  ConfigPage.tsx full implementation (Jails accordion editor,
  Global config, Server settings, Regex Tester with preview)
- Fixed pre-existing frontend lint: JSX.Element → React.JSX.Element
  (10 files), void/promise patterns in useServerStatus + useJails,
  no-misused-spread in client.ts, eslint.config.ts self-excluded

frontend/eslint.config.ts

@@ -4,7 +4,7 @@ import reactHooks from "eslint-plugin-react-hooks";
 import prettierConfig from "eslint-config-prettier";
 
 export default tseslint.config(
-  { ignores: ["dist"] },
+  { ignores: ["dist", "eslint.config.ts"] },
   {
     extends: [js.configs.recommended, ...tseslint.configs.strictTypeChecked],
     files: ["**/*.{ts,tsx}"],

frontend/src/App.tsx

@@ -38,7 +38,7 @@ import { BlocklistsPage } from "./pages/BlocklistsPage";
 /**
  * Root application component — mounts providers and top-level routes.
  */
-function App(): JSX.Element {
+function App(): React.JSX.Element {
   return (
     <FluentProvider theme={lightTheme}>
       <BrowserRouter>

frontend/src/api/client.ts

@@ -57,7 +57,7 @@ async function request<T>(url: string, options: RequestInit = {}): Promise<T> {
     credentials: "include",
     headers: {
       "Content-Type": "application/json",
-      ...options.headers,
+      ...(options.headers as Record<string, string> | undefined),
     },
   });
 

frontend/src/api/config.ts

@@ -0,0 +1,121 @@
+/**
+ * API functions for the configuration and server settings endpoints.
+ */
+
+import { get, post, put } from "./client";
+import { ENDPOINTS } from "./endpoints";
+import type {
+  AddLogPathRequest,
+  GlobalConfig,
+  GlobalConfigUpdate,
+  JailConfigListResponse,
+  JailConfigResponse,
+  JailConfigUpdate,
+  LogPreviewRequest,
+  LogPreviewResponse,
+  RegexTestRequest,
+  RegexTestResponse,
+  ServerSettingsResponse,
+  ServerSettingsUpdate,
+} from "../types/config";
+
+// ---------------------------------------------------------------------------
+// Jail configuration
+// ---------------------------------------------------------------------------
+
+export async function fetchJailConfigs(
+): Promise<JailConfigListResponse> {
+  return get<JailConfigListResponse>(ENDPOINTS.configJails);
+}
+
+export async function fetchJailConfig(
+  name: string
+): Promise<JailConfigResponse> {
+  return get<JailConfigResponse>(ENDPOINTS.configJail(name));
+}
+
+export async function updateJailConfig(
+  name: string,
+  update: JailConfigUpdate
+): Promise<void> {
+  await put<undefined>(ENDPOINTS.configJail(name), update);
+}
+
+// ---------------------------------------------------------------------------
+// Global configuration
+// ---------------------------------------------------------------------------
+
+export async function fetchGlobalConfig(
+): Promise<GlobalConfig> {
+  return get<GlobalConfig>(ENDPOINTS.configGlobal);
+}
+
+export async function updateGlobalConfig(
+  update: GlobalConfigUpdate
+): Promise<void> {
+  await put<undefined>(ENDPOINTS.configGlobal, update);
+}
+
+// ---------------------------------------------------------------------------
+// Reload
+// ---------------------------------------------------------------------------
+
+export async function reloadConfig(
+): Promise<void> {
+  await post<undefined>(ENDPOINTS.configReload, undefined);
+}
+
+// ---------------------------------------------------------------------------
+// Regex tester
+// ---------------------------------------------------------------------------
+
+export async function testRegex(
+  req: RegexTestRequest
+): Promise<RegexTestResponse> {
+  return post<RegexTestResponse>(ENDPOINTS.configRegexTest, req);
+}
+
+// ---------------------------------------------------------------------------
+// Log path management
+// ---------------------------------------------------------------------------
+
+export async function addLogPath(
+  jailName: string,
+  req: AddLogPathRequest
+): Promise<void> {
+  await post<undefined>(ENDPOINTS.configJailLogPath(jailName), req);
+}
+
+// ---------------------------------------------------------------------------
+// Log preview
+// ---------------------------------------------------------------------------
+
+export async function previewLog(
+  req: LogPreviewRequest
+): Promise<LogPreviewResponse> {
+  return post<LogPreviewResponse>(ENDPOINTS.configPreviewLog, req);
+}
+
+// ---------------------------------------------------------------------------
+// Server settings
+// ---------------------------------------------------------------------------
+
+export async function fetchServerSettings(
+): Promise<ServerSettingsResponse> {
+  return get<ServerSettingsResponse>(ENDPOINTS.serverSettings);
+}
+
+export async function updateServerSettings(
+  update: ServerSettingsUpdate
+): Promise<void> {
+  await put<undefined>(ENDPOINTS.serverSettings, update);
+}
+
+export async function flushLogs(
+): Promise<string> {
+  const resp = await post<{ message: string }>(
+    ENDPOINTS.serverFlushLogs,
+    undefined,
+  );
+  return resp.message;
+}

frontend/src/api/endpoints.ts

@@ -58,9 +58,12 @@ export const ENDPOINTS = {
   // -------------------------------------------------------------------------
   configJails: "/config/jails",
   configJail: (name: string): string => `/config/jails/${encodeURIComponent(name)}`,
+  configJailLogPath: (name: string): string =>
+    `/config/jails/${encodeURIComponent(name)}/logpath`,
   configGlobal: "/config/global",
   configReload: "/config/reload",
   configRegexTest: "/config/regex-test",
+  configPreviewLog: "/config/preview-log",
 
   // -------------------------------------------------------------------------
   // Server settings

frontend/src/components/RequireAuth.tsx

@@ -11,7 +11,7 @@ import { useAuth } from "../providers/AuthProvider";
 
 interface RequireAuthProps {
   /** The protected page content to render when authenticated. */
-  children: JSX.Element;
+  children: React.JSX.Element;
 }
 
 /**
@@ -20,7 +20,7 @@ interface RequireAuthProps {
  * Redirects to `/login?next=<path>` otherwise so the intended destination is
  * preserved and honoured after a successful login.
  */
-export function RequireAuth({ children }: RequireAuthProps): JSX.Element {
+export function RequireAuth({ children }: RequireAuthProps): React.JSX.Element {
   const { isAuthenticated } = useAuth();
   const location = useLocation();
 

frontend/src/components/ServerStatusBar.tsx

@@ -81,7 +81,7 @@ const useStyles = makeStyles({
  * Render this at the top of the dashboard page (and any page that should
  * show live server status).
  */
-export function ServerStatusBar(): JSX.Element {
+export function ServerStatusBar(): React.JSX.Element {
   const styles = useStyles();
   const { status, loading, error, refresh } = useServerStatus();
 

frontend/src/hooks/useConfig.ts

@@ -0,0 +1,355 @@
+/**
+ * React hooks for the configuration and server settings data.
+ */
+
+import { useCallback, useEffect, useRef, useState } from "react";
+import {
+  addLogPath,
+  fetchGlobalConfig,
+  fetchJailConfig,
+  fetchJailConfigs,
+  fetchServerSettings,
+  flushLogs,
+  previewLog,
+  reloadConfig,
+  testRegex,
+  updateGlobalConfig,
+  updateJailConfig,
+  updateServerSettings,
+} from "../api/config";
+import type {
+  AddLogPathRequest,
+  GlobalConfig,
+  GlobalConfigUpdate,
+  JailConfig,
+  JailConfigUpdate,
+  LogPreviewRequest,
+  LogPreviewResponse,
+  RegexTestRequest,
+  RegexTestResponse,
+  ServerSettings,
+  ServerSettingsUpdate,
+} from "../types/config";
+
+// ---------------------------------------------------------------------------
+// useJailConfigs — list all jail configs
+// ---------------------------------------------------------------------------
+
+interface UseJailConfigsResult {
+  jails: JailConfig[];
+  total: number;
+  loading: boolean;
+  error: string | null;
+  refresh: () => void;
+  updateJail: (name: string, update: JailConfigUpdate) => Promise<void>;
+  reloadAll: () => Promise<void>;
+}
+
+export function useJailConfigs(): UseJailConfigsResult {
+  const [jails, setJails] = useState<JailConfig[]>([]);
+  const [total, setTotal] = useState(0);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+  const abortRef = useRef<AbortController | null>(null);
+
+  const load = useCallback((): void => {
+    abortRef.current?.abort();
+    const ctrl = new AbortController();
+    abortRef.current = ctrl;
+    setLoading(true);
+    setError(null);
+
+    fetchJailConfigs()
+      .then((resp) => {
+        setJails(resp.jails);
+        setTotal(resp.total);
+      })
+      .catch((err: unknown) => {
+        if (err instanceof Error && err.name !== "AbortError") {
+          setError(err.message);
+        }
+      })
+      .finally(() => {
+        setLoading(false);
+      });
+  }, []);
+
+  useEffect(() => {
+    load();
+    return (): void => {
+      abortRef.current?.abort();
+    };
+  }, [load]);
+
+  const updateJail = useCallback(
+    async (name: string, update: JailConfigUpdate): Promise<void> => {
+      await updateJailConfig(name, update);
+      load();
+    },
+    [load],
+  );
+
+  const reloadAll = useCallback(async (): Promise<void> => {
+    await reloadConfig();
+    load();
+  }, [load]);
+
+  return { jails, total, loading, error, refresh: load, updateJail, reloadAll };
+}
+
+// ---------------------------------------------------------------------------
+// useJailConfigDetail — single jail config with mutation
+// ---------------------------------------------------------------------------
+
+interface UseJailConfigDetailResult {
+  jail: JailConfig | null;
+  loading: boolean;
+  error: string | null;
+  refresh: () => void;
+  updateJail: (update: JailConfigUpdate) => Promise<void>;
+  addLog: (req: AddLogPathRequest) => Promise<void>;
+}
+
+export function useJailConfigDetail(name: string): UseJailConfigDetailResult {
+  const [jail, setJail] = useState<JailConfig | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+  const abortRef = useRef<AbortController | null>(null);
+
+  const load = useCallback((): void => {
+    abortRef.current?.abort();
+    const ctrl = new AbortController();
+    abortRef.current = ctrl;
+    setLoading(true);
+    setError(null);
+
+    fetchJailConfig(name)
+      .then((resp) => {
+        setJail(resp.jail);
+      })
+      .catch((err: unknown) => {
+        if (err instanceof Error && err.name !== "AbortError") {
+          setError(err.message);
+        }
+      })
+      .finally(() => {
+        setLoading(false);
+      });
+  }, [name]);
+
+  useEffect(() => {
+    load();
+    return (): void => {
+      abortRef.current?.abort();
+    };
+  }, [load]);
+
+  const updateJail = useCallback(
+    async (update: JailConfigUpdate): Promise<void> => {
+      await updateJailConfig(name, update);
+      load();
+    },
+    [name, load],
+  );
+
+  const addLog = useCallback(
+    async (req: AddLogPathRequest): Promise<void> => {
+      await addLogPath(name, req);
+      load();
+    },
+    [name, load],
+  );
+
+  return { jail, loading, error, refresh: load, updateJail, addLog };
+}
+
+// ---------------------------------------------------------------------------
+// useGlobalConfig
+// ---------------------------------------------------------------------------
+
+interface UseGlobalConfigResult {
+  config: GlobalConfig | null;
+  loading: boolean;
+  error: string | null;
+  refresh: () => void;
+  updateConfig: (update: GlobalConfigUpdate) => Promise<void>;
+}
+
+export function useGlobalConfig(): UseGlobalConfigResult {
+  const [config, setConfig] = useState<GlobalConfig | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+  const abortRef = useRef<AbortController | null>(null);
+
+  const load = useCallback((): void => {
+    abortRef.current?.abort();
+    const ctrl = new AbortController();
+    abortRef.current = ctrl;
+    setLoading(true);
+    setError(null);
+
+    fetchGlobalConfig()
+      .then(setConfig)
+      .catch((err: unknown) => {
+        if (err instanceof Error && err.name !== "AbortError") {
+          setError(err.message);
+        }
+      })
+      .finally(() => {
+        setLoading(false);
+      });
+  }, []);
+
+  useEffect(() => {
+    load();
+    return (): void => {
+      abortRef.current?.abort();
+    };
+  }, [load]);
+
+  const updateConfig = useCallback(
+    async (update: GlobalConfigUpdate): Promise<void> => {
+      await updateGlobalConfig(update);
+      load();
+    },
+    [load],
+  );
+
+  return { config, loading, error, refresh: load, updateConfig };
+}
+
+// ---------------------------------------------------------------------------
+// useServerSettings
+// ---------------------------------------------------------------------------
+
+interface UseServerSettingsResult {
+  settings: ServerSettings | null;
+  loading: boolean;
+  error: string | null;
+  refresh: () => void;
+  updateSettings: (update: ServerSettingsUpdate) => Promise<void>;
+  flush: () => Promise<string>;
+}
+
+export function useServerSettings(): UseServerSettingsResult {
+  const [settings, setSettings] = useState<ServerSettings | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState<string | null>(null);
+  const abortRef = useRef<AbortController | null>(null);
+
+  const load = useCallback((): void => {
+    abortRef.current?.abort();
+    const ctrl = new AbortController();
+    abortRef.current = ctrl;
+    setLoading(true);
+    setError(null);
+
+    fetchServerSettings()
+      .then((resp) => {
+        setSettings(resp.settings);
+      })
+      .catch((err: unknown) => {
+        if (err instanceof Error && err.name !== "AbortError") {
+          setError(err.message);
+        }
+      })
+      .finally(() => {
+        setLoading(false);
+      });
+  }, []);
+
+  useEffect(() => {
+    load();
+    return (): void => {
+      abortRef.current?.abort();
+    };
+  }, [load]);
+
+  const updateSettings_ = useCallback(
+    async (update: ServerSettingsUpdate): Promise<void> => {
+      await updateServerSettings(update);
+      load();
+    },
+    [load],
+  );
+
+  const flush = useCallback(async (): Promise<string> => {
+    return flushLogs();
+  }, []);
+
+  return {
+    settings,
+    loading,
+    error,
+    refresh: load,
+    updateSettings: updateSettings_,
+    flush,
+  };
+}
+
+// ---------------------------------------------------------------------------
+// useRegexTester — lazy, triggered by test(req)
+// ---------------------------------------------------------------------------
+
+interface UseRegexTesterResult {
+  result: RegexTestResponse | null;
+  testing: boolean;
+  test: (req: RegexTestRequest) => Promise<void>;
+}
+
+export function useRegexTester(): UseRegexTesterResult {
+  const [result, setResult] = useState<RegexTestResponse | null>(null);
+  const [testing, setTesting] = useState(false);
+
+  const test_ = useCallback(async (req: RegexTestRequest): Promise<void> => {
+    setTesting(true);
+    try {
+      const resp = await testRegex(req);
+      setResult(resp);
+    } catch (err: unknown) {
+      if (err instanceof Error) {
+        setResult({ matched: false, groups: [], error: err.message });
+      }
+    } finally {
+      setTesting(false);
+    }
+  }, []);
+
+  return { result, testing, test: test_ };
+}
+
+// ---------------------------------------------------------------------------
+// useLogPreview — lazy, triggered by preview(req)
+// ---------------------------------------------------------------------------
+
+interface UseLogPreviewResult {
+  preview: LogPreviewResponse | null;
+  loading: boolean;
+  run: (req: LogPreviewRequest) => Promise<void>;
+}
+
+export function useLogPreview(): UseLogPreviewResult {
+  const [preview, setPreview] = useState<LogPreviewResponse | null>(null);
+  const [loading, setLoading] = useState(false);
+
+  const run_ = useCallback(async (req: LogPreviewRequest): Promise<void> => {
+    setLoading(true);
+    try {
+      const resp = await previewLog(req);
+      setPreview(resp);
+    } catch (err: unknown) {
+      if (err instanceof Error) {
+        setPreview({
+          lines: [],
+          total_lines: 0,
+          matched_count: 0,
+          regex_error: err.message,
+        });
+      }
+    } finally {
+      setLoading(false);
+    }
+  }, []);
+
+  return { preview, loading, run: run_ };
+}

frontend/src/hooks/useJails.ts

@@ -100,7 +100,7 @@ export function useJails(): UseJailsResult {
 
   useEffect(() => {
     load();
-    return () => {
+    return (): void => {
       abortRef.current?.abort();
     };
   }, [load]);
@@ -120,9 +120,9 @@ export function useJails(): UseJailsResult {
     refresh: load,
     startJail: withRefresh(startJail),
     stopJail: withRefresh(stopJail),
-    setIdle: (name, on) => setJailIdle(name, on).then(() => load()),
+    setIdle: (name, on) => setJailIdle(name, on).then((): void => { load(); }),
     reloadJail: withRefresh(reloadJail),
-    reloadAll: () => reloadAllJails().then(() => load()),
+    reloadAll: () => reloadAllJails().then((): void => { load(); }),
   };
 }
 
@@ -191,7 +191,7 @@ export function useJailDetail(name: string): UseJailDetailResult {
 
   useEffect(() => {
     load();
-    return () => {
+    return (): void => {
       abortRef.current?.abort();
     };
   }, [load]);
@@ -278,7 +278,7 @@ export function useActiveBans(): UseActiveBansResult {
 
   useEffect(() => {
     load();
-    return () => {
+    return (): void => {
       abortRef.current?.abort();
     };
   }, [load]);

frontend/src/hooks/useServerStatus.ts

@@ -36,7 +36,7 @@ export function useServerStatus(): UseServerStatusResult {
   const [error, setError] = useState<string | null>(null);
 
   // Use a ref so the fetch function identity is stable.
-  const fetchRef = useRef<() => void>(() => undefined);
+  const fetchRef = useRef<() => Promise<void>>(async () => Promise.resolve());
 
   const doFetch = useCallback(async (): Promise<void> => {
     setLoading(true);
@@ -54,14 +54,14 @@ export function useServerStatus(): UseServerStatusResult {
   fetchRef.current = doFetch;
 
   // Initial fetch + polling interval.
-  useEffect(() => {
-    void doFetch();
+  useEffect((): (() => void) => {
+    void doFetch().catch((): void => undefined);
 
-    const id = setInterval(() => {
-      void fetchRef.current();
+    const id = setInterval((): void => {
+      void fetchRef.current().catch((): void => undefined);
     }, POLL_INTERVAL_MS);
 
-    return () => clearInterval(id);
+    return (): void => { clearInterval(id); };
   }, [doFetch]);
 
   // Refetch on window focus.
@@ -70,11 +70,11 @@ export function useServerStatus(): UseServerStatusResult {
       void fetchRef.current();
     };
     window.addEventListener("focus", onFocus);
-    return () => window.removeEventListener("focus", onFocus);
+    return (): void => { window.removeEventListener("focus", onFocus); };
   }, []);
 
   const refresh = useCallback((): void => {
-    void doFetch();
+    void doFetch().catch((): void => undefined);
   }, [doFetch]);
 
   return { status, loading, error, refresh };

frontend/src/layouts/MainLayout.tsx

@@ -176,7 +176,7 @@ const NAV_ITEMS: NavItem[] = [
  * Renders child routes via `<Outlet />`.  Use inside React Router
  * as a layout route wrapping all authenticated pages.
  */
-export function MainLayout(): JSX.Element {
+export function MainLayout(): React.JSX.Element {
   const styles = useStyles();
   const { logout } = useAuth();
   const navigate = useNavigate();

frontend/src/pages/BlocklistsPage.tsx

@@ -8,7 +8,7 @@ const useStyles = makeStyles({
   root: { padding: tokens.spacingVerticalXXL },
 });
 
-export function BlocklistsPage(): JSX.Element {
+export function BlocklistsPage(): React.JSX.Element {
   const styles = useStyles();
   return (
     <div className={styles.root}>

frontend/src/pages/HistoryPage.tsx

@@ -8,7 +8,7 @@ const useStyles = makeStyles({
   root: { padding: tokens.spacingVerticalXXL },
 });
 
-export function HistoryPage(): JSX.Element {
+export function HistoryPage(): React.JSX.Element {
   const styles = useStyles();
   return (
     <div className={styles.root}>

frontend/src/pages/LoginPage.tsx

@@ -71,7 +71,7 @@ const useStyles = makeStyles({
 /**
  * Login page — single password input, no username.
  */
-export function LoginPage(): JSX.Element {
+export function LoginPage(): React.JSX.Element {
   const styles = useStyles();
   const navigate = useNavigate();
   const [searchParams] = useSearchParams();

frontend/src/pages/MapPage.tsx

@@ -8,7 +8,7 @@ const useStyles = makeStyles({
   root: { padding: tokens.spacingVerticalXXL },
 });
 
-export function MapPage(): JSX.Element {
+export function MapPage(): React.JSX.Element {
   const styles = useStyles();
   return (
     <div className={styles.root}>

frontend/src/pages/SetupPage.tsx

@@ -96,7 +96,7 @@ const DEFAULT_VALUES: FormValues = {
  * First-run setup wizard page.
  * Collects master password and server preferences.
  */
-export function SetupPage(): JSX.Element {
+export function SetupPage(): React.JSX.Element {
   const styles = useStyles();
   const navigate = useNavigate();
 

frontend/src/providers/AuthProvider.tsx

@@ -60,7 +60,7 @@ export function AuthProvider({
   children,
 }: {
   children: React.ReactNode;
-}): JSX.Element {
+}): React.JSX.Element {
   const [auth, setAuth] = useState<AuthState>(() => ({
     token: sessionStorage.getItem(SESSION_KEY),
     expiresAt: sessionStorage.getItem(SESSION_EXPIRES_KEY),

frontend/src/types/config.ts

@@ -0,0 +1,130 @@
+/**
+ * TypeScript interfaces for the configuration and server settings API.
+ */
+
+// ---------------------------------------------------------------------------
+// Jail Configuration
+// ---------------------------------------------------------------------------
+
+export interface JailConfig {
+  name: string;
+  ban_time: number;
+  max_retry: number;
+  find_time: number;
+  fail_regex: string[];
+  ignore_regex: string[];
+  log_paths: string[];
+  date_pattern: string | null;
+  log_encoding: string;
+  backend: string;
+  actions: string[];
+}
+
+export interface JailConfigResponse {
+  jail: JailConfig;
+}
+
+export interface JailConfigListResponse {
+  jails: JailConfig[];
+  total: number;
+}
+
+export interface JailConfigUpdate {
+  ban_time?: number | null;
+  max_retry?: number | null;
+  find_time?: number | null;
+  fail_regex?: string[] | null;
+  ignore_regex?: string[] | null;
+  date_pattern?: string | null;
+  dns_mode?: string | null;
+  enabled?: boolean | null;
+}
+
+// ---------------------------------------------------------------------------
+// Global Configuration
+// ---------------------------------------------------------------------------
+
+export interface GlobalConfig {
+  log_level: string;
+  log_target: string;
+  db_purge_age: number;
+  db_max_matches: number;
+}
+
+export interface GlobalConfigUpdate {
+  log_level?: string | null;
+  log_target?: string | null;
+  db_purge_age?: number | null;
+  db_max_matches?: number | null;
+}
+
+// ---------------------------------------------------------------------------
+// Server Settings
+// ---------------------------------------------------------------------------
+
+export interface ServerSettings {
+  log_level: string;
+  log_target: string;
+  syslog_socket: string | null;
+  db_path: string;
+  db_purge_age: number;
+  db_max_matches: number;
+}
+
+export interface ServerSettingsResponse {
+  settings: ServerSettings;
+}
+
+export interface ServerSettingsUpdate {
+  log_level?: string | null;
+  log_target?: string | null;
+  db_purge_age?: number | null;
+  db_max_matches?: number | null;
+}
+
+// ---------------------------------------------------------------------------
+// Regex Tester
+// ---------------------------------------------------------------------------
+
+export interface RegexTestRequest {
+  log_line: string;
+  fail_regex: string;
+}
+
+export interface RegexTestResponse {
+  matched: boolean;
+  groups: string[];
+  error: string | null;
+}
+
+// ---------------------------------------------------------------------------
+// Log Preview
+// ---------------------------------------------------------------------------
+
+export interface LogPreviewRequest {
+  log_path: string;
+  fail_regex: string;
+  num_lines?: number;
+}
+
+export interface LogPreviewLine {
+  line: string;
+  matched: boolean;
+  groups: string[];
+}
+
+export interface LogPreviewResponse {
+  lines: LogPreviewLine[];
+  total_lines: number;
+  matched_count: number;
+  regex_error: string | null;
+}
+
+// ---------------------------------------------------------------------------
+// Add Log Path
+// ---------------------------------------------------------------------------
+
+export interface AddLogPathRequest {
+  log_path: string;
+  tail?: boolean;
+}