fixed authentication middleware

* backend code

* fixed twitch authentication

.gitignore

@@ -29,3 +29,4 @@ frontend/.yarn/install-state.gz
 livestreams.dat
 .vite/deps
 archive.txt
+twitch-monitor.dat

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "yt-dlp-webui",
-  "version": "3.2.5",
+  "version": "3.2.6",
   "description": "Frontend compontent of yt-dlp-webui",
   "scripts": {
     "dev": "vite --host 0.0.0.0",
@@ -18,11 +18,11 @@
     "@mui/icons-material": "^6.2.0",
     "@mui/material": "^6.2.0",
     "fp-ts": "^2.16.5",
+    "jotai": "^2.10.3",
     "react": "^19.0.0",
     "react-dom": "^19.0.0",
     "react-router-dom": "^6.23.1",
     "react-virtuoso": "^4.7.11",
-    "jotai": "^2.10.3",
     "rxjs": "^7.8.1"
   },
   "devDependencies": {

frontend/src/Layout.tsx

@@ -28,6 +28,7 @@ import Footer from './components/Footer'
 import Logout from './components/Logout'
 import SocketSubscriber from './components/SocketSubscriber'
 import ThemeToggler from './components/ThemeToggler'
+import TwitchIcon from './components/TwitchIcon'
 import { useI18n } from './hooks/useI18n'
 import Toaster from './providers/ToasterProvider'
 import { getAccentValue } from './utils'
@@ -154,6 +155,19 @@ export default function Layout() {
                 <ListItemText primary={i18n.t('subscriptionsButtonLabel')} />
               </ListItemButton>
             </Link>
+            <Link to={'/twitch'} style={
+              {
+                textDecoration: 'none',
+                color: mode === 'dark' ? '#ffffff' : '#000000DE'
+              }
+            }>
+              <ListItemButton>
+                <ListItemIcon>
+                  <TwitchIcon />
+                </ListItemIcon>
+                <ListItemText primary={"Twitch"} />
+              </ListItemButton>
+            </Link>
             <Link to={'/monitor'} style={
               {
                 textDecoration: 'none',

frontend/src/assets/i18n/en_US.yaml

@@ -80,4 +80,7 @@ keys:
   cronExpressionLabel: 'Cron expression'
   editButtonLabel: 'Edit'
   newSubscriptionButton: New subscription
-  clearCompletedButton: 'Clear completed'
+  clearCompletedButton: 'Clear completed'
+  twitchIntegrationInfo: |
+    To enable monitoring Twitch streams follow this wiki page.
+    https://github.com/marcopiovanello/yt-dlp-web-ui/wiki/Twitch-integration

frontend/src/components/HomeSpeedDial.tsx

@@ -32,7 +32,6 @@ const HomeSpeedDial: React.FC<Props> = ({ onDownloadOpen, onEditorOpen }) => {
       ariaLabel="Home speed dial"
       sx={{ position: 'absolute', bottom: 64, right: 24 }}
       icon={<SpeedDialIcon />}
-      onClick={onDownloadOpen}
     >
       <SpeedDialAction
         icon={listView ? <ViewAgendaIcon /> : <FormatListBulleted />}

frontend/src/components/TwitchIcon.tsx

@@ -0,0 +1,22 @@
+import { useAtomValue } from 'jotai'
+import { settingsState } from '../atoms/settings'
+
+const TwitchIcon: React.FC = () => {
+  const { theme } = useAtomValue(settingsState)
+
+  return (
+    <svg
+      role="img"
+      viewBox="0 0 24 24"
+      width={24}
+      height={24}
+      xmlns="http://www.w3.org/2000/svg"
+      style={{ fill: theme === 'dark' ? '#fff' : '#757575' }}
+    >
+      <title>Twitch</title>
+      <path d="M11.571 4.714h1.715v5.143H11.57zm4.715 0H18v5.143h-1.714zM6 0L1.714 4.286v15.428h5.143V24l4.286-4.286h3.428L22.286 12V0zm14.571 11.143l-3.428 3.428h-3.429l-3 3v-3H6.857V1.714h13.714Z" />
+    </svg>
+  )
+}
+
+export default TwitchIcon

frontend/src/components/twitch/TwitchDialog.tsx

@@ -0,0 +1,140 @@
+import CloseIcon from '@mui/icons-material/Close'
+import {
+  Alert,
+  AppBar,
+  Box,
+  Button,
+  Container,
+  Dialog,
+  Grid,
+  IconButton,
+  Paper,
+  Slide,
+  TextField,
+  Toolbar,
+  Typography
+} from '@mui/material'
+import { TransitionProps } from '@mui/material/transitions'
+import { matchW } from 'fp-ts/lib/Either'
+import { pipe } from 'fp-ts/lib/function'
+import { useAtomValue } from 'jotai'
+import { forwardRef, startTransition, useState } from 'react'
+import { serverURL } from '../../atoms/settings'
+import { useToast } from '../../hooks/toast'
+import { useI18n } from '../../hooks/useI18n'
+import { ffetch } from '../../lib/httpClient'
+
+type Props = {
+  open: boolean
+  onClose: () => void
+}
+
+const Transition = forwardRef(function Transition(
+  props: TransitionProps & {
+    children: React.ReactElement
+  },
+  ref: React.Ref<unknown>,
+) {
+  return <Slide direction="up" ref={ref} {...props} />
+})
+
+const TwitchDialog: React.FC<Props> = ({ open, onClose }) => {
+  const [channelURL, setChannelURL] = useState('')
+
+  const { i18n } = useI18n()
+  const { pushMessage } = useToast()
+
+  const baseURL = useAtomValue(serverURL)
+
+  const submit = async (channelURL: string) => {
+    const task = ffetch<void>(`${baseURL}/twitch/user`, {
+      method: 'POST',
+      body: JSON.stringify({
+        user: channelURL.split('/').at(-1)
+      })
+    })
+    const either = await task()
+
+    pipe(
+      either,
+      matchW(
+        (l) => pushMessage(l, 'error'),
+        (_) => onClose()
+      )
+    )
+  }
+
+  return (
+    <Dialog
+      fullScreen
+      open={open}
+      onClose={onClose}
+      TransitionComponent={Transition}
+    >
+      <AppBar sx={{ position: 'relative' }}>
+        <Toolbar>
+          <IconButton
+            edge="start"
+            color="inherit"
+            onClick={onClose}
+            aria-label="close"
+          >
+            <CloseIcon />
+          </IconButton>
+          <Typography sx={{ ml: 2, flex: 1 }} variant="h6" component="div">
+            {i18n.t('subscriptionsButtonLabel')}
+          </Typography>
+        </Toolbar>
+      </AppBar>
+      <Box sx={{
+        backgroundColor: (theme) => theme.palette.background.default,
+        minHeight: (theme) => `calc(99vh - ${theme.mixins.toolbar.minHeight}px)`
+      }}>
+        <Container sx={{ my: 4 }}>
+          <Grid container spacing={2}>
+            <Grid item xs={12}>
+              <Paper
+                elevation={4}
+                sx={{
+                  p: 2,
+                  display: 'flex',
+                  flexDirection: 'column',
+                }}
+              >
+                <Grid container gap={1.5}>
+                  <Grid item xs={12}>
+                    <Alert severity="info">
+                      {i18n.t('twitchIntegrationInfo')}
+                    </Alert>
+                  </Grid>
+                  <Grid item xs={12} mt={1}>
+                    <TextField
+                      multiline
+                      fullWidth
+                      label={i18n.t('subscriptionsURLInput')}
+                      variant="outlined"
+                      placeholder="https://www.twitch.tv/a_twitch_user_that_exists"
+                      onChange={(e) => setChannelURL(e.target.value)}
+                    />
+                  </Grid>
+                  <Grid item xs={12}>
+                    <Button
+                      sx={{ mt: 2 }}
+                      variant="contained"
+                      disabled={channelURL === ''}
+                      onClick={() => startTransition(() => submit(channelURL))}
+                    >
+                      {i18n.t('startButton')}
+                    </Button>
+                  </Grid>
+                </Grid>
+              </Paper>
+            </Grid>
+          </Grid>
+        </Container>
+      </Box>
+    </Dialog>
+  )
+}
+
+export default TwitchDialog

frontend/src/router.tsx

@@ -6,6 +6,7 @@ import Terminal from './views/Terminal'
 
 const Home = lazy(() => import('./views/Home'))
 const Login = lazy(() => import('./views/Login'))
+const Twitch = lazy(() => import('./views/Twitch'))
 const Archive = lazy(() => import('./views/Archive'))
 const Settings = lazy(() => import('./views/Settings'))
 const LiveStream = lazy(() => import('./views/Livestream'))
@@ -111,6 +112,14 @@ export const router = createHashRouter([
           </Suspense >
         )
       },
+      {
+        path: '/twitch',
+        element: (
+          <Suspense fallback={<CircularProgress />}>
+            <Twitch />
+          </Suspense >
+        )
+      },
     ]
   },
 ])

frontend/src/views/Twitch.tsx

@@ -0,0 +1,77 @@
+import {
+  Chip,
+  Container,
+  Paper
+} from '@mui/material'
+import { matchW } from 'fp-ts/lib/Either'
+import { pipe } from 'fp-ts/lib/function'
+import { useAtomValue } from 'jotai'
+import { useState, useTransition } from 'react'
+import { serverURL } from '../atoms/settings'
+import LoadingBackdrop from '../components/LoadingBackdrop'
+import NoSubscriptions from '../components/subscriptions/NoSubscriptions'
+import SubscriptionsSpeedDial from '../components/subscriptions/SubscriptionsSpeedDial'
+import TwitchDialog from '../components/twitch/TwitchDialog'
+import { useToast } from '../hooks/toast'
+import useFetch from '../hooks/useFetch'
+import { ffetch } from '../lib/httpClient'
+
+const TwitchView: React.FC = () => {
+  const { pushMessage } = useToast()
+
+  const baseURL = useAtomValue(serverURL)
+
+  const [openDialog, setOpenDialog] = useState(false)
+
+  const { data: users, fetcher: refetch } = useFetch<Array<string>>('/twitch/users')
+
+  const [isPending, startTransition] = useTransition()
+
+  const deleteUser = async (user: string) => {
+    const task = ffetch<void>(`${baseURL}/twitch/user/${user}`, {
+      method: 'DELETE',
+    })
+    const either = await task()
+
+    pipe(
+      either,
+      matchW(
+        (l) => pushMessage(l, 'error'),
+        () => refetch()
+      )
+    )
+  }
+
+  return (
+    <>
+      <LoadingBackdrop isLoading={!users || isPending} />
+
+      <SubscriptionsSpeedDial onOpen={() => setOpenDialog(s => !s)} />
+
+      <TwitchDialog open={openDialog} onClose={() => {
+        setOpenDialog(s => !s)
+        refetch()
+      }} />
+
+      {
+        !users || users.length === 0 ?
+          <NoSubscriptions /> :
+          <Container maxWidth="xl" sx={{ mt: 4, mb: 8 }}>
+            <Paper sx={{
+              p: 2.5,
+              minHeight: '80vh',
+            }}>
+              {users.map(user => (
+                <Chip
+                  label={user}
+                  onDelete={() => startTransition(async () => await deleteUser(user))}
+                />
+              ))}
+            </Paper>
+          </Container>
+      }
+    </>
+  )
+}
+
+export default TwitchView

server/config/config.go

@@ -4,6 +4,7 @@ import (
 	"os"
 	"path/filepath"
 	"sync"
+	"time"
 
 	"gopkg.in/yaml.v3"
 )
@@ -31,6 +32,11 @@ type Config struct {
 	OpenIdEmailWhitelist []string `yaml:"openid_email_whitelist"`
 	FrontendPath         string   `yaml:"frontend_path"`
 	AutoArchive          bool     `yaml:"auto_archive"`
+	Twitch               struct {
+		ClientId      string        `yaml:"client_id"`
+		ClientSecret  string        `yaml:"client_secret"`
+		CheckInterval time.Duration `yaml:"check_interval"`
+	} `yaml:"twitch"`
 }
 
 var (
@@ -42,6 +48,7 @@ func Instance() *Config {
 	if instance == nil {
 		instanceOnce.Do(func() {
 			instance = &Config{}
+			instance.Twitch.CheckInterval = time.Minute * 5
 		})
 	}
 	return instance

server/internal/process.go

@@ -93,7 +93,6 @@ func (p *Process) Start() {
 
 	baseParams := []string{
 		strings.Split(p.Url, "?list")[0], //no playlist
-		"--no-exec",
 		"--newline",
 		"--no-colors",
 		"--no-playlist",
@@ -101,6 +100,7 @@ func (p *Process) Start() {
 		templateReplacer.Replace(downloadTemplate),
 		"--progress-template",
 		templateReplacer.Replace(postprocessTemplate),
+		"--no-exec",
 	}
 
 	// if user asked to manually override the output path...

server/middleware/utils.go

@@ -0,0 +1,21 @@
+package middlewares
+
+import (
+	"net/http"
+
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/config"
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/openid"
+)
+
+func ApplyAuthenticationByConfig(next http.Handler) http.Handler {
+    handler := next
+
+    if config.Instance().RequireAuth {
+        handler = Authenticated(handler)
+    }
+    if config.Instance().UseOpenId {
+        handler = openid.Middleware(handler)
+    }
+
+    return handler
+}

server/rest/service.go

@@ -164,7 +164,7 @@ func (s *Service) DeleteTemplate(ctx context.Context, id string) error {
 
 func (s *Service) GetVersion(ctx context.Context) (string, string, error) {
 	//TODO: load from realease properties file, or anything else outside code
-	const CURRENT_RPC_VERSION = "3.2.5"
+	const CURRENT_RPC_VERSION = "3.2.6"
 
 	result := make(chan string, 1)
 

server/server.go

@@ -34,6 +34,7 @@ import (
 	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/status"
 	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/subscription"
 	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/subscription/task"
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/twitch"
 	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/user"
 
 	_ "modernc.org/sqlite"
@@ -51,6 +52,7 @@ type serverConfig struct {
 	db       *sql.DB
 	mq       *internal.MessageQueue
 	lm       *livestream.Monitor
+	tm       *twitch.Monitor
 }
 
 // TODO: change scope
@@ -115,17 +117,33 @@ func RunBlocking(rc *RunConfig) {
 	go lm.Schedule()
 	go lm.Restore()
 
-	srv := newServer(serverConfig{
+	tm := twitch.NewMonitor(
+		twitch.NewAuthenticationManager(
+			config.Instance().Twitch.ClientId,
+			config.Instance().Twitch.ClientSecret,
+		),
+	)
+	go tm.Monitor(
+		context.TODO(),
+		config.Instance().Twitch.CheckInterval,
+		twitch.DEFAULT_DOWNLOAD_HANDLER(mdb, mq),
+	)
+	go tm.Restore()
+
+	scfg := serverConfig{
 		frontend: rc.App,
 		swagger:  rc.Swagger,
 		mdb:      mdb,
 		mq:       mq,
 		db:       db,
 		lm:       lm,
-	})
+		tm:       tm,
+	}
 
-	go gracefulShutdown(srv, mdb)
-	go autoPersist(time.Minute*5, mdb, lm)
+	srv := newServer(scfg)
+
+	go gracefulShutdown(srv, &scfg)
+	go autoPersist(time.Minute*5, mdb, lm, tm)
 
 	var (
 		network = "tcp"
@@ -188,12 +206,7 @@ func newServer(c serverConfig) *http.Server {
 
 	// Filebrowser routes
 	r.Route("/filebrowser", func(r chi.Router) {
-		if config.Instance().RequireAuth {
-			r.Use(middlewares.Authenticated)
-		}
-		if config.Instance().UseOpenId {
-			r.Use(openid.Middleware)
-		}
+		r.Use(middlewares.ApplyAuthenticationByConfig)
 		r.Post("/downloaded", filebrowser.ListDownloaded)
 		r.Post("/delete", filebrowser.DeleteFile)
 		r.Get("/d/{id}", filebrowser.DownloadFile)
@@ -235,10 +248,18 @@ func newServer(c serverConfig) *http.Server {
 	// Subscriptions
 	r.Route("/subscriptions", subscription.Container(c.db, cronTaskRunner).ApplyRouter())
 
+	// Twitch
+	r.Route("/twitch", func(r chi.Router) {
+		r.Use(middlewares.ApplyAuthenticationByConfig)
+		r.Get("/users", twitch.GetMonitoredUsers(c.tm))
+		r.Post("/user", twitch.MonitorUserHandler(c.tm))
+		r.Delete("/user/{user}", twitch.DeleteUser(c.tm))
+	})
+
 	return &http.Server{Handler: r}
 }
 
-func gracefulShutdown(srv *http.Server, db *internal.MemoryDB) {
+func gracefulShutdown(srv *http.Server, cfg *serverConfig) {
 	ctx, stop := signal.NotifyContext(context.Background(),
 		os.Interrupt,
 		syscall.SIGTERM,
@@ -250,7 +271,9 @@ func gracefulShutdown(srv *http.Server, db *internal.MemoryDB) {
 		slog.Info("shutdown signal received")
 
 		defer func() {
-			db.Persist()
+			cfg.mdb.Persist()
+			cfg.lm.Persist()
+			cfg.tm.Persist()
 
 			stop()
 			srv.Shutdown(context.Background())
@@ -258,8 +281,14 @@ func gracefulShutdown(srv *http.Server, db *internal.MemoryDB) {
 	}()
 }
 
-func autoPersist(d time.Duration, db *internal.MemoryDB, lm *livestream.Monitor) {
+func autoPersist(
+	d time.Duration,
+	db *internal.MemoryDB,
+	lm *livestream.Monitor,
+	tm *twitch.Monitor,
+) {
 	for {
+		time.Sleep(d)
 		if err := db.Persist(); err != nil {
 			slog.Warn("failed to persisted session", slog.Any("err", err))
 		}
@@ -267,7 +296,10 @@ func autoPersist(d time.Duration, db *internal.MemoryDB, lm *livestream.Monitor)
 			slog.Warn(
 				"failed to persisted livestreams monitor session", slog.Any("err", err.Error()))
 		}
+		if err := tm.Persist(); err != nil {
+			slog.Warn(
+				"failed to persisted twitch monitor session", slog.Any("err", err.Error()))
+		}
 		slog.Debug("sucessfully persisted session")
-		time.Sleep(d)
 	}
 }

server/twitch/auth.go

@@ -0,0 +1,75 @@
+package twitch
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+	"time"
+)
+
+const authURL = "https://id.twitch.tv/oauth2/token"
+
+type AuthResponse struct {
+	AccessToken string `json:"access_token"`
+	ExpiresIn   int    `json:"expires_in"`
+	TokenType   string `json:"token_type"`
+}
+
+type AccessToken struct {
+	Token  string
+	Expiry time.Time
+}
+
+type AuthenticationManager struct {
+	clientId     string
+	clientSecret string
+	accesToken   *AccessToken
+}
+
+func NewAuthenticationManager(clientId, clientSecret string) *AuthenticationManager {
+	return &AuthenticationManager{
+		clientId:     clientId,
+		clientSecret: clientSecret,
+		accesToken:   &AccessToken{},
+	}
+}
+
+func (a *AuthenticationManager) GetAccessToken() (*AccessToken, error) {
+	if a.accesToken != nil && a.accesToken.Token != "" && a.accesToken.Expiry.After(time.Now()) {
+		return a.accesToken, nil
+	}
+
+	data := url.Values{}
+	data.Set("client_id", a.clientId)
+	data.Set("client_secret", a.clientSecret)
+	data.Set("grant_type", "client_credentials")
+
+	resp, err := http.PostForm(authURL, data)
+	if err != nil {
+		return nil, fmt.Errorf("errore richiesta token: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("status non OK: %s", resp.Status)
+	}
+
+	var auth AuthResponse
+	if err := json.NewDecoder(resp.Body).Decode(&auth); err != nil {
+		return nil, fmt.Errorf("errore decoding JSON: %w", err)
+	}
+
+	token := &AccessToken{
+		Token:  auth.AccessToken,
+		Expiry: time.Now().Add(time.Duration(auth.ExpiresIn) * time.Second),
+	}
+
+	a.accesToken = token
+
+	return token, nil
+}
+
+func (a *AuthenticationManager) GetClientId() string {
+	return a.clientId
+}

server/twitch/client.go

@@ -0,0 +1,91 @@
+package twitch
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"time"
+)
+
+const twitchAPIURL = "https://api.twitch.tv/helix"
+
+type Client struct {
+	authenticationManager AuthenticationManager
+}
+
+func NewTwitchClient(am *AuthenticationManager) *Client {
+	return &Client{
+		authenticationManager: *am,
+	}
+}
+
+type streamResp struct {
+	Data []struct {
+		ID        string `json:"id"`
+		UserName  string `json:"user_name"`
+		Title     string `json:"title"`
+		GameName  string `json:"game_name"`
+		StartedAt string `json:"started_at"`
+	} `json:"data"`
+}
+
+func (c *Client) doRequest(endpoint string, params map[string]string) ([]byte, error) {
+	token, err := c.authenticationManager.GetAccessToken()
+	if err != nil {
+		return nil, err
+	}
+
+	reqURL := twitchAPIURL + endpoint
+	req, err := http.NewRequest("GET", reqURL, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	q := req.URL.Query()
+	for k, v := range params {
+		q.Set(k, v)
+	}
+	req.URL.RawQuery = q.Encode()
+
+	req.Header.Set("Client-Id", c.authenticationManager.GetClientId())
+	req.Header.Set("Authorization", "Bearer "+token.Token)
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	return io.ReadAll(resp.Body)
+}
+
+func (c *Client) PollStream(channel string, liveChannel chan<- *StreamInfo) error {
+	body, err := c.doRequest("/streams", map[string]string{"user_login": channel})
+	if err != nil {
+		return err
+	}
+
+	var sr streamResp
+	if err := json.Unmarshal(body, &sr); err != nil {
+		return err
+	}
+
+	if len(sr.Data) == 0 {
+		liveChannel <- &StreamInfo{UserName: channel, IsLive: false}
+		return nil
+	}
+
+	s := sr.Data[0]
+	started, _ := time.Parse(time.RFC3339, s.StartedAt)
+
+	liveChannel <- &StreamInfo{
+		ID:        s.ID,
+		UserName:  s.UserName,
+		Title:     s.Title,
+		GameName:  s.GameName,
+		StartedAt: started,
+		IsLive:    true,
+	}
+
+	return nil
+}

server/twitch/monitor.go

@@ -0,0 +1,149 @@
+package twitch
+
+import (
+	"context"
+	"encoding/gob"
+	"fmt"
+	"iter"
+	"log/slog"
+	"maps"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/config"
+	"github.com/marcopiovanello/yt-dlp-web-ui/v3/server/internal"
+)
+
+type Monitor struct {
+	liveChannel           chan *StreamInfo
+	monitored             map[string]*Client
+	lastState             map[string]bool
+	mu                    sync.RWMutex
+	authenticationManager *AuthenticationManager
+}
+
+func NewMonitor(authenticationManager *AuthenticationManager) *Monitor {
+	return &Monitor{
+		liveChannel:           make(chan *StreamInfo, 16),
+		monitored:             make(map[string]*Client),
+		lastState:             make(map[string]bool),
+		authenticationManager: authenticationManager,
+	}
+}
+
+func (m *Monitor) Add(user string) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.monitored[user] = NewTwitchClient(m.authenticationManager)
+	slog.Info("added user to twitch monitor", slog.String("user", user))
+}
+
+func (m *Monitor) Monitor(ctx context.Context, interval time.Duration, handler func(url string) error) {
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ticker.C:
+			m.mu.RLock()
+			for user, client := range m.monitored {
+				u := user
+				c := client
+
+				go func() {
+					if err := c.PollStream(u, m.liveChannel); err != nil {
+						slog.Error("polling failed", slog.String("user", u), slog.Any("err", err))
+					}
+				}()
+			}
+			m.mu.RUnlock()
+
+		case stream := <-m.liveChannel:
+			wasLive := m.lastState[stream.UserName]
+			if stream.IsLive && !wasLive {
+				slog.Info("stream went live", slog.String("user", stream.UserName))
+				if err := handler(fmt.Sprintf("https://www.twitch.tv/%s", stream.UserName)); err != nil {
+					slog.Error("handler failed", slog.String("user", stream.UserName), slog.Any("err", err))
+				}
+			}
+			m.lastState[stream.UserName] = stream.IsLive
+
+		case <-ctx.Done():
+			slog.Info("stopping twitch monitor")
+			return
+		}
+	}
+}
+
+func (m *Monitor) GetMonitoredUsers() iter.Seq[string] {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+	return maps.Keys(m.monitored)
+}
+
+func (m *Monitor) DeleteUser(user string) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	delete(m.monitored, user)
+	delete(m.lastState, user)
+}
+
+func DEFAULT_DOWNLOAD_HANDLER(db *internal.MemoryDB, mq *internal.MessageQueue) func(url string) error {
+	return func(url string) error {
+		p := &internal.Process{
+			Url:        url,
+			Livestream: true,
+			Params:     []string{"--downloader", "ffmpeg", "--no-part"},
+		}
+		db.Set(p)
+		mq.Publish(p)
+		return nil
+	}
+}
+
+func (m *Monitor) Persist() error {
+	filename := filepath.Join(config.Instance().SessionFilePath, "twitch-monitor.dat")
+
+	f, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	enc := gob.NewEncoder(f)
+	users := make([]string, 0, len(m.monitored))
+
+	for user := range m.monitored {
+		users = append(users, user)
+	}
+
+	return enc.Encode(users)
+}
+
+func (m *Monitor) Restore() error {
+	filename := filepath.Join(config.Instance().SessionFilePath, "twitch-monitor.dat")
+
+	f, err := os.Open(filename)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil
+		}
+		return err
+	}
+	defer f.Close()
+
+	dec := gob.NewDecoder(f)
+	var users []string
+	if err := dec.Decode(&users); err != nil {
+		return err
+	}
+
+	m.monitored = make(map[string]*Client)
+	for _, user := range users {
+		m.monitored[user] = NewTwitchClient(m.authenticationManager)
+	}
+
+	return nil
+}

server/twitch/rest.go

@@ -0,0 +1,65 @@
+package twitch
+
+import (
+	"encoding/json"
+	"net/http"
+	"slices"
+
+	"github.com/go-chi/chi/v5"
+)
+
+type addUserReq struct {
+	User string `json:"user"`
+}
+
+func MonitorUserHandler(m *Monitor) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		var req addUserReq
+
+		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		m.Add(req.User)
+
+		if err := json.NewEncoder(w).Encode("ok"); err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+	}
+}
+
+func GetMonitoredUsers(m *Monitor) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		it := m.GetMonitoredUsers()
+
+		users := slices.Collect(it)
+		if users == nil {
+			users = make([]string, 0)
+		}
+
+		if err := json.NewEncoder(w).Encode(users); err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+	}
+}
+
+func DeleteUser(m *Monitor) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		user := chi.URLParam(r, "user")
+
+		if user == "" {
+			http.Error(w, "empty user", http.StatusBadRequest)
+			return
+		}
+
+		m.DeleteUser(user)
+
+		if err := json.NewEncoder(w).Encode("ok"); err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+	}
+}

server/twitch/types.go

@@ -0,0 +1,20 @@
+package twitch
+
+import "time"
+
+type StreamInfo struct {
+	ID        string
+	UserName  string
+	Title     string
+	GameName  string
+	StartedAt time.Time
+	IsLive    bool
+}
+
+type VodInfo struct {
+	ID        string
+	Title     string
+	URL       string
+	Duration  string
+	CreatedAt time.Time
+}