Per-user podcasts, file uploads, RSS images, Docker support

- Each user owns a podcast: podcast title/author/image on users table
- Episodes scoped by user_id with context-based auth
- Audio file upload replaces URL linking, served from /uploads/
- Podcast and per-episode images with itunes:image in RSS
- RSS per-user via ?user=N, dashboard shows user-specific feed URL
- Settings form for title + author + image per user
- Docker multi-stage build (golang:1.25-alpine / alpine:3.21)
- Removed PODSTALK_TITLE/AUTHOR env vars

handler/episode.go

@@ -23,28 +23,36 @@ type EpisodeHandler struct {
 }
 
 func (h *EpisodeHandler) ServeDashboard(w http.ResponseWriter, r *http.Request) {
-	episodes, err := h.Store.ListEpisodes()
+	userID := UserIDFromContext(r)
+	user, err := h.Store.GetUser(userID)
+	if err != nil {
+		http.Error(w, "user not found", http.StatusInternalServerError)
+		return
+	}
+
+	episodes, err := h.Store.ListEpisodes(userID)
 	if err != nil {
 		http.Error(w, "failed to load episodes", http.StatusInternalServerError)
 		return
 	}
 
-	title, _ := h.Store.GetSetting("podcast_title")
+	title := user.PodcastTitle
 	if title == "" {
 		title = "Podstalk"
 	}
-
-	podcastImage, _ := h.Store.GetSetting("podcast_image")
-
 	h.Tpl.Render(w, "dashboard", map[string]any{
-		"Episodes":     episodes,
-		"PodcastTitle": title,
-		"PodcastImage": podcastImage,
-		"BaseURL":      h.BaseURL,
+		"Episodes":      episodes,
+		"PodcastTitle":  title,
+		"PodcastImage":  user.PodcastImage,
+		"PodcastAuthor": user.PodcastAuthor,
+		"BaseURL":       h.BaseURL,
+		"UserID":        user.ID,
 	})
 }
 
 func (h *EpisodeHandler) ServeNew(w http.ResponseWriter, r *http.Request) {
+	userID := UserIDFromContext(r)
+
 	if r.Method == http.MethodGet {
 		h.Tpl.Render(w, "episode_form", map[string]any{"Editing": false})
 		return
@@ -89,7 +97,7 @@ func (h *EpisodeHandler) ServeNew(w http.ResponseWriter, r *http.Request) {
 
 		imagePath, _ := h.saveUploadedFile(r, "image_file", "images")
 
-		_, err = h.Store.CreateEpisode(title, description, audioPath, imagePath, publishedAt)
+		_, err = h.Store.CreateEpisode(userID, title, description, audioPath, imagePath, publishedAt)
 		if err != nil {
 			h.Tpl.Render(w, "episode_form", map[string]any{
 				"Editing": false,
@@ -151,7 +159,6 @@ func (h *EpisodeHandler) ServeEdit(w http.ResponseWriter, r *http.Request) {
 			return
 		}
 
-		// Load existing episode to know which files to replace
 		existing, err := h.Store.GetEpisode(id)
 		if err != nil {
 			http.Error(w, "episode not found", http.StatusNotFound)
@@ -191,7 +198,6 @@ func (h *EpisodeHandler) ServeDelete(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// Delete associated files
 	ep, err := h.Store.GetEpisode(id)
 	if err == nil {
 		h.removeUploadedFile(ep.AudioPath)
@@ -205,9 +211,7 @@ func (h *EpisodeHandler) ServeDelete(w http.ResponseWriter, r *http.Request) {
 	http.Redirect(w, r, "/", http.StatusSeeOther)
 }
 
-// ServeUpload serves files from the upload directory.
 func (h *EpisodeHandler) ServeUpload(w http.ResponseWriter, r *http.Request) {
-	// Strip /uploads/ prefix to get the relative path
 	relPath := strings.TrimPrefix(r.URL.Path, "/uploads/")
 	if relPath == "" || strings.Contains(relPath, "..") {
 		http.Error(w, "invalid path", http.StatusBadRequest)
@@ -216,8 +220,6 @@ func (h *EpisodeHandler) ServeUpload(w http.ResponseWriter, r *http.Request) {
 	http.ServeFile(w, r, filepath.Join(h.UploadDir, relPath))
 }
 
-// saveUploadedFile saves a file from a multipart form field to the upload directory.
-// Returns the relative path (category/filename) or empty string if no file uploaded.
 func (h *EpisodeHandler) saveUploadedFile(r *http.Request, field, category string) (string, error) {
 	file, header, err := r.FormFile(field)
 	if err != nil {
@@ -260,7 +262,6 @@ func (h *EpisodeHandler) removeUploadedFile(relPath string) {
 }
 
 func sanitizeFilename(name string) string {
-	// Keep only the base name, lowercased, alphanumeric + dots + dashes
 	name = filepath.Base(name)
 	name = strings.Map(func(r rune) rune {
 		if r >= 'a' && r <= 'z' || r >= '0' && r <= '9' || r == '.' || r == '-' {