Add configurable formats and lazy decoders, v0.7.1

.env.example

@@ -11,6 +11,9 @@ APP_NAME=Photo Date Editor
 APP_TITLE=Mork Photo Date Editor
 # Optional text shown directly below the page heading.
 APP_SUBTITLE=Family photo metadata editor
+# Enabled groups: jpg, png, tiff, heif, dng
+# Use ENABLED_FORMATS=jpg for a JPEG-only workflow.
+ENABLED_FORMATS=jpg,png,tiff,heif,dng
 MAX_UPLOAD_MB=150
 LOG_LEVEL=INFO
 
@@ -27,4 +30,4 @@ DEFAULT_MAP_LON=11.0
 DEFAULT_MAP_ZOOM=5
 GEOCODER_URL=https://nominatim.openstreetmap.org/search
 # Optional custom identification sent to the geocoder. The default uses APP_NAME, version and APP_URL.
-# GEOCODER_USER_AGENT=MorkPhotoDateEditor/0.7.0 (+https://edit.mork.fyi)
+# GEOCODER_USER_AGENT=MorkPhotoDateEditor/0.7.1 (+https://edit.mork.fyi)

CHANGELOG.md

@@ -1,5 +1,18 @@
 # Changelog
 
+## 0.7.1
+
+- Add `ENABLED_FORMATS` with the available groups `jpg`, `png`, `tiff`, `heif`, and `dng`.
+- Expand each group to its associated extensions and expose the enabled groups/extensions through `/api/config`.
+- Omit disabled formats from browser folder scans and reject them at backend metadata, preview, and processing endpoints.
+- Generate the default page subtitle and empty-folder guidance from the enabled format groups.
+- Validate configuration strictly so unknown or empty format lists fail clearly at startup.
+- Load `pillow-heif` only on the first HEIF preview.
+- Prefer an embedded DNG preview without loading LibRaw, and import `rawpy` only when a rendered DNG fallback is actually required.
+- Keep a decoder loaded after first use until container restart, avoiding repeated load/unload overhead.
+- Preserve all format behavior when `ENABLED_FORMATS` is omitted.
+- Bump the application and service-worker cache version to 0.7.1.
+
 ## 0.7.0
 
 - Add DNG folder scanning, `DNG` format badges, and format-sort compatibility.

README.md

@@ -1,6 +1,6 @@
 # Photo Date Editor
 
-Version 0.7.0
+Version 0.7.1
 
 A self-hosted browser UI for manually dating scanned photographs. The browser receives temporary read/write access to a local computer or Chromebook folder, sends one image at a time to the Docker backend for ExifTool processing, and overwrites the same local file after processing.
 
@@ -54,6 +54,7 @@ APP_PORT=8080
 APP_NAME=Photo Date Editor
 APP_TITLE=Mork Photo Date Editor
 APP_SUBTITLE=Family photo metadata editor
+ENABLED_FORMATS=jpg,png,tiff,heif,dng
 MAX_UPLOAD_MB=150
 LOG_LEVEL=INFO
 
@@ -72,7 +73,35 @@ GEOCODER_URL=https://nominatim.openstreetmap.org/search
 
 Open the configured HTTPS URL through Caddy, click **Open photo folder**, and grant read/write access.
 
-## Upgrade from 0.1 through 0.6.1
+## Enabled formats
+
+`ENABLED_FORMATS` accepts a comma-separated list of format groups:
+
+| Group | File extensions |
+|---|---|
+| `jpg` | `.jpg`, `.jpeg` |
+| `png` | `.png` |
+| `tiff` | `.tif`, `.tiff` |
+| `heif` | `.heic`, `.heif`, `.hif` |
+| `dng` | `.dng` |
+
+The default enables every group:
+
+```dotenv
+ENABLED_FORMATS=jpg,png,tiff,heif,dng
+```
+
+For a JPEG-only installation:
+
+```dotenv
+ENABLED_FORMATS=jpg
+```
+
+Disabled formats are omitted from folder scans and rejected by the backend. The page subtitle and empty-folder message reflect the enabled groups. Unknown group names stop application startup with a clear configuration error instead of silently enabling or disabling the wrong format.
+
+HEIF and DNG decoders load lazily. A JPEG-only process does not import them. After the first applicable preview, the decoder remains loaded until the container restarts; repeatedly unloading it would add avoidable delay and memory churn. For DNG, LibRaw is loaded only if no usable embedded JPEG preview is available.
+
+## Upgrade from 0.1 through 0.7
 
 Replace the project files with this version and rebuild:
 
@@ -80,7 +109,7 @@ Replace the project files with this version and rebuild:
 docker compose up -d --build
 ```
 
-The existing `.env` can be kept. `APP_TITLE` and `APP_SUBTITLE` are optional. When `APP_TITLE` is omitted, the visible page title continues to use `APP_NAME`; the subtitle uses the built-in format description when omitted. Browser progress from earlier releases remains compatible. A normal refresh should load the new service-worker cache; use a hard refresh if an old UI remains visible.
+The existing `.env` can be kept. When `ENABLED_FORMATS` is omitted, all current format groups remain enabled. `APP_TITLE` and `APP_SUBTITLE` are optional. When `APP_TITLE` is omitted, the visible page title continues to use `APP_NAME`; when `APP_SUBTITLE` is omitted, it is generated from the enabled formats. Browser progress from earlier releases remains compatible. A normal refresh should load the new service-worker cache; use a hard refresh if an old UI remains visible.
 
 ## Caddy example
 

app/main.py

@@ -24,33 +24,78 @@ from pydantic import BaseModel, Field
 from fastapi.responses import FileResponse, Response
 from fastapi.staticfiles import StaticFiles
 from PIL import Image, ImageOps, UnidentifiedImageError
-from pillow_heif import register_heif_opener
-import rawpy
 
-register_heif_opener()
+FORMAT_GROUPS: dict[str, tuple[str, ...]] = {
+    "jpg": (".jpg", ".jpeg"),
+    "png": (".png",),
+    "tiff": (".tif", ".tiff"),
+    "heif": (".heic", ".heif", ".hif"),
+    "dng": (".dng",),
+}
+FORMAT_LABELS = {
+    "jpg": "JPG",
+    "png": "PNG",
+    "tiff": "TIFF",
+    "heif": "HEIF",
+    "dng": "DNG",
+}
+
+
+def _enabled_format_groups() -> tuple[str, ...]:
+    configured = os.getenv("ENABLED_FORMATS", ",".join(FORMAT_GROUPS))
+    requested = tuple(dict.fromkeys(
+        value.strip().casefold()
+        for value in configured.split(",")
+        if value.strip()
+    ))
+    unknown = sorted(set(requested) - set(FORMAT_GROUPS))
+    if unknown:
+        raise RuntimeError(
+            "Unknown ENABLED_FORMATS value(s): "
+            f"{', '.join(unknown)}. Available groups: {', '.join(FORMAT_GROUPS)}."
+        )
+    if not requested:
+        raise RuntimeError("ENABLED_FORMATS must contain at least one format group.")
+    return tuple(group for group in FORMAT_GROUPS if group in requested)
+
+
+def _format_list_text(groups: tuple[str, ...]) -> str:
+    labels = [FORMAT_LABELS[group] for group in groups]
+    if len(labels) == 1:
+        return labels[0]
+    if len(labels) == 2:
+        return " and ".join(labels)
+    return f"{', '.join(labels[:-1])} and {labels[-1]}"
+
+
+ENABLED_FORMAT_GROUPS = _enabled_format_groups()
+SUPPORTED_EXTENSIONS = {
+    extension
+    for group in ENABLED_FORMAT_GROUPS
+    for extension in FORMAT_GROUPS[group]
+}
+ENABLED_FORMAT_LABEL = _format_list_text(ENABLED_FORMAT_GROUPS)
 
 APP_NAME = os.getenv("APP_NAME", "Photo Date Editor")
 APP_TITLE = os.getenv("APP_TITLE") or APP_NAME
 APP_SUBTITLE = (
     os.getenv("APP_SUBTITLE")
-    or "Local folder · in-place JPG, PNG, TIFF and HEIF metadata"
+    or f"Local folder · in-place {ENABLED_FORMAT_LABEL} metadata"
 )
 APP_URL = os.getenv("APP_URL", "http://localhost:8080")
-APP_VERSION = "0.7.0"
+APP_VERSION = "0.7.1"
 MAX_UPLOAD_MB = int(os.getenv("MAX_UPLOAD_MB", "150"))
 MAX_UPLOAD_BYTES = MAX_UPLOAD_MB * 1024 * 1024
 PREVIEW_MAX_EDGE = int(os.getenv("PREVIEW_MAX_EDGE", "2400"))
 PREVIEW_MAX_PIXELS = int(os.getenv("PREVIEW_MAX_PIXELS", "300000000"))
 Image.MAX_IMAGE_PIXELS = PREVIEW_MAX_PIXELS
 
-SUPPORTED_EXTENSIONS = {
-    ".jpg", ".jpeg", ".png", ".tif", ".tiff",
-    ".heic", ".heif", ".hif", ".dng",
-}
 TIFF_EXTENSIONS = {".tif", ".tiff"}
 HEIF_EXTENSIONS = {".heic", ".heif", ".hif"}
 DNG_EXTENSIONS = {".dng"}
-SERVER_PREVIEW_EXTENSIONS = TIFF_EXTENSIONS | HEIF_EXTENSIONS | DNG_EXTENSIONS
+SERVER_PREVIEW_EXTENSIONS = (
+    TIFF_EXTENSIONS | HEIF_EXTENSIONS | DNG_EXTENSIONS
+) & SUPPORTED_EXTENSIONS
 MEDIA_TYPES = {
     ".jpg": "image/jpeg",
     ".jpeg": "image/jpeg",
@@ -87,6 +132,9 @@ _last_geocode_request = 0.0
 _tile_cache: OrderedDict[str, tuple[bytes, str]] = OrderedDict()
 _tile_cache_limit = 512
 _tile_lock = asyncio.Lock()
+_decoder_lock = threading.Lock()
+_heif_decoder_registered = False
+_rawpy_module: Any | None = None
 
 logging.basicConfig(
     level=getattr(logging, LOG_LEVEL, logging.INFO),
@@ -116,7 +164,7 @@ def health() -> dict[str, str]:
 
 
 @app.get("/api/config")
-def config() -> dict[str, str | int | float]:
+def config() -> dict[str, Any]:
     return {
         "appName": APP_NAME,
         "appTitle": APP_TITLE,
@@ -124,6 +172,9 @@ def config() -> dict[str, str | int | float]:
         "appUrl": APP_URL,
         "version": APP_VERSION,
         "maxUploadMb": MAX_UPLOAD_MB,
+        "enabledFormats": list(ENABLED_FORMAT_GROUPS),
+        "enabledExtensions": sorted(SUPPORTED_EXTENSIONS),
+        "enabledFormatLabel": ENABLED_FORMAT_LABEL,
         "mapTileUrl": "/api/map/tiles/{z}/{x}/{y}.png",
         "mapAttribution": MAP_ATTRIBUTION,
         "defaultMapLat": DEFAULT_MAP_LAT,
@@ -585,6 +636,35 @@ def _metadata_values(metadata: dict[str, Any]) -> tuple[bool, bool, dict[str, An
     return has_metadata, edited_by_app, values
 
 
+def _ensure_heif_decoder() -> None:
+    """Register pillow-heif once, on the first HEIF preview request."""
+    global _heif_decoder_registered
+    if _heif_decoder_registered:
+        return
+    with _decoder_lock:
+        if _heif_decoder_registered:
+            return
+        from pillow_heif import register_heif_opener
+
+        register_heif_opener()
+        _heif_decoder_registered = True
+        logger.info("HEIF preview decoder loaded.")
+
+
+def _get_rawpy() -> Any:
+    """Import rawpy once, on the first DNG that needs a rendered fallback."""
+    global _rawpy_module
+    if _rawpy_module is not None:
+        return _rawpy_module
+    with _decoder_lock:
+        if _rawpy_module is None:
+            import rawpy
+
+            _rawpy_module = rawpy
+            logger.info("DNG LibRaw preview decoder loaded.")
+    return _rawpy_module
+
+
 def _embedded_dng_preview(path: Path) -> Image.Image | None:
     """Return the first usable DNG preview, preferring the largest common tags."""
     for tag in ("JpgFromRaw", "PreviewImage", "ThumbnailImage"):
@@ -611,6 +691,7 @@ def _embedded_dng_preview(path: Path) -> Image.Image | None:
 
 def _render_dng(path: Path) -> Image.Image:
     """Render a half-size RGB fallback when a DNG has no embedded JPEG preview."""
+    rawpy = _get_rawpy()
     try:
         with rawpy.imread(str(path)) as raw:
             width = int(raw.sizes.width)
@@ -634,6 +715,11 @@ async def create_preview(file: Annotated[UploadFile, File(...)]) -> Response:
     """Generate a temporary browser-friendly preview for TIFF, HEIF, and DNG images."""
     filename = file.filename or "photo.tiff"
     suffix = Path(filename).suffix.lower()
+    if suffix not in SUPPORTED_EXTENSIONS:
+        raise HTTPException(
+            status_code=415,
+            detail=f"This format is disabled. Enabled format groups: {ENABLED_FORMAT_LABEL}.",
+        )
     if suffix not in SERVER_PREVIEW_EXTENSIONS:
         raise HTTPException(
             status_code=415,
@@ -650,6 +736,8 @@ async def create_preview(file: Annotated[UploadFile, File(...)]) -> Response:
                     preview = _render_dng(temp_path)
                 preview = ImageOps.exif_transpose(preview)
             else:
+                if suffix in HEIF_EXTENSIONS:
+                    _ensure_heif_decoder()
                 with Image.open(temp_path) as source:
                     source.seek(0)
                     preview = ImageOps.exif_transpose(source)
@@ -692,7 +780,7 @@ async def read_metadata(file: Annotated[UploadFile, File(...)]) -> dict[str, boo
     if suffix not in SUPPORTED_EXTENSIONS:
         raise HTTPException(
             status_code=415,
-            detail="Supported formats are JPG, JPEG, PNG, TIF, TIFF, HEIC, HEIF, HIF, and DNG.",
+            detail=f"This format is disabled. Enabled format groups: {ENABLED_FORMAT_LABEL}.",
         )
 
     with tempfile.TemporaryDirectory(prefix="photo-date-editor-read-") as temp_dir:
@@ -761,7 +849,7 @@ async def process_photo(
     if suffix not in SUPPORTED_EXTENSIONS:
         raise HTTPException(
             status_code=415,
-            detail="Supported formats are JPG, JPEG, PNG, TIF, TIFF, HEIC, HEIF, HIF, and DNG.",
+            detail=f"This format is disabled. Enabled format groups: {ENABLED_FORMAT_LABEL}.",
         )
 
     exif_datetime, xmp_date, precision_label = _normalise_datetime(

app/static/app.js

@@ -13,6 +13,9 @@ const state = {
   mapMarker: null,
   locationDirty: false,
   favoriteLocations: [],
+  configPromise: null,
+  enabledExtensions: new Set(),
+  enabledFormatLabel: '',
 };
 
 const $ = (selector) => document.querySelector(selector);
@@ -128,6 +131,12 @@ function requiresServerPreview(photo) {
   return photo.format === 'TIFF' || photo.format === 'HEIF' || photo.format === 'DNG';
 }
 
+function isEnabledFilename(filename) {
+  const dot = filename.lastIndexOf('.');
+  if (dot < 0) return false;
+  return state.enabledExtensions.has(filename.slice(dot).toLowerCase());
+}
+
 function storageKey() {
   return state.directoryHandle ? `photo-date-editor:${state.directoryHandle.name}` : null;
 }
@@ -154,14 +163,13 @@ function saveFolderState() {
 }
 
 async function openFolder() {
-  await loadFavoriteLocations();
-
-  if (!isSupported()) {
-    showToast('Use a current Chromium browser over HTTPS. Folder access is unavailable here.', true);
-    return;
-  }
-
   try {
+    await loadAppConfig();
+    await loadFavoriteLocations();
+    if (!isSupported()) {
+      showToast('Use a current Chromium browser over HTTPS. Folder access is unavailable here.', true);
+      return;
+    }
     const handle = await window.showDirectoryPicker({ mode: 'readwrite', id: 'photo-date-editor' });
     const permission = await handle.requestPermission({ mode: 'readwrite' });
     if (permission !== 'granted') throw new Error('Read/write permission was not granted.');
@@ -179,7 +187,7 @@ async function scanFolder() {
   const photos = [];
 
   for await (const [name, handle] of state.directoryHandle.entries()) {
-    if (handle.kind !== 'file' || !/\.(jpe?g|png|tiff?|heic|heif|hif|dng)$/i.test(name)) continue;
+    if (handle.kind !== 'file' || !isEnabledFilename(name)) continue;
     const file = await handle.getFile();
     const previous = stored.photos?.[name] || {};
     const unchanged = !previous.lastModified || previous.lastModified === file.lastModified;
@@ -218,7 +226,7 @@ async function scanFolder() {
   } else {
     elements.viewerContent.classList.add('hidden');
     elements.viewerEmpty.classList.remove('hidden');
-    showToast('No JPG, PNG, TIFF, HEIC, HEIF, HIF, or DNG files were found in that folder.', true);
+    showToast(`No enabled ${state.enabledFormatLabel} files were found in that folder.`, true);
   }
 }
 
@@ -1026,18 +1034,34 @@ window.addEventListener('keydown', (event) => {
   else if (!typing && event.key.toLowerCase() === 'c') copyPreviousValues();
 });
 
-async function initialise() {
+function loadAppConfig() {
-  try {
+  if (!state.configPromise) {
-    const response = await fetch('/api/config', { cache: 'no-store' });
+    state.configPromise = (async () => {
-    if (response.ok) {
+      const response = await fetch('/api/config', { cache: 'no-store' });
+      if (!response.ok) throw new Error(`Configuration request failed (${response.status}).`);
       const config = await response.json();
+      const extensions = Array.isArray(config.enabledExtensions) ? config.enabledExtensions : [];
+      if (!extensions.length) throw new Error('The server has no enabled photo formats.');
       const pageTitle = config.appTitle || config.appName;
       elements.appName.textContent = pageTitle;
       elements.appSubtitle.textContent = config.appSubtitle;
       document.title = pageTitle;
       state.mapConfig = config;
-    }
+      state.enabledExtensions = new Set(extensions.map((value) => String(value).toLowerCase()));
-  } catch {}
+      state.enabledFormatLabel = config.enabledFormatLabel || 'photo';
+      return config;
+    })();
+  }
+  return state.configPromise;
+}
+
+async function initialise() {
+  try {
+    await loadAppConfig();
+  } catch (error) {
+    setSaveStatus('failed', 'Configuration unavailable', error.message || 'Could not load enabled formats.');
+    for (const button of elements.openButtons) button.disabled = true;
+  }
 
   // Favorite locations are server-side shared data and must be loaded on every page start,
   // independently of whether the user opens a photo folder in this browser session.

app/static/index.html

@@ -16,7 +16,7 @@
         <div class="brand-mark" aria-hidden="true">◫</div>
         <div>
           <h1 id="app-name">Photo Date Editor</h1>
-          <p id="app-subtitle">Local folder · in-place JPG, PNG, TIFF, HEIF and DNG metadata</p>
+          <p id="app-subtitle">Loading enabled photo formats…</p>
         </div>
       </div>
       <div class="top-actions">
@@ -74,7 +74,7 @@
             </select>
           </div>
           <div id="file-list" class="file-list" aria-live="polite">
-            <div class="empty-list">Choose a folder containing JPG, PNG, TIFF, HEIC, HEIF, HIF, or DNG photos.</div>
+            <div class="empty-list">Choose a folder containing an enabled photo format.</div>
           </div>
         </section>
 

app/static/service-worker.js

@@ -1,4 +1,4 @@
-const CACHE_NAME = 'photo-date-editor-v7-0';
+const CACHE_NAME = 'photo-date-editor-v7-1';
 const SHELL = ['/', '/styles.css', '/app.js', '/manifest.webmanifest', '/vendor/leaflet/leaflet.css', '/vendor/leaflet/leaflet.js'];
 
 self.addEventListener('install', (event) => {

docker-compose.yml

@@ -12,6 +12,7 @@ services:
       APP_NAME: "${APP_NAME:-Photo Date Editor}"
       APP_TITLE: "${APP_TITLE:-}"
       APP_SUBTITLE: "${APP_SUBTITLE:-}"
+      ENABLED_FORMATS: "${ENABLED_FORMATS:-jpg,png,tiff,heif,dng}"
       MAX_UPLOAD_MB: "${MAX_UPLOAD_MB:-150}"
       LOG_LEVEL: "${LOG_LEVEL:-INFO}"
       DATA_DIR: "/data"