[videogames] Fix how we scan for new RA playlogs

vrobbler/apps/scrobbles/importers/webdav.py

@@ -20,7 +20,7 @@ DEFAULT_EBIRD_PATH = "var/ebird/"
 DEFAULT_SCALE_PATH = "var/scale/"
 
 
-def import_from_webdav_for_all_users(restart=False):
+def import_from_webdav_for_all_users(restart=False, update_retroarch_hash=False):
     """Iterate all WebDAV-enabled users, scanning each media-type directory."""
     webdav_enabled_user_ids = UserProfile.objects.filter(
         webdav_url__isnull=False,
@@ -46,7 +46,9 @@ def import_from_webdav_for_all_users(restart=False):
         logger.info("Scanning WebDAV gpx for user %s", user_id)
         gpx_count += scan_webdav_for_gpx(client, user_id)
         logger.info("Scanning WebDAV retroarch for user %s", user_id)
-        retro_count += scan_webdav_for_retroarch(client, user_id)
+        retro_count += scan_webdav_for_retroarch(
+            client, user_id, update_hash_only=update_retroarch_hash
+        )
         logger.info("Scanning WebDAV bgstats for user %s", user_id)
         bgstats_count += scan_webdav_for_bgstats(client, user_id)
         logger.info("Scanning WebDAV ebird for user %s", user_id)
@@ -182,8 +184,18 @@ def scan_webdav_for_gpx(webdav_client, user_id):
     return new_imports
 
 
-def scan_webdav_for_retroarch(webdav_client, user_id):
-    """Download all .lrtl files from WebDAV, zip them, queue one import."""
+def scan_webdav_for_retroarch(webdav_client, user_id, update_hash_only=False):
+    """Check for new .lrtl files on WebDAV, download+import if changed.
+
+    Uses ETags from a single PROPFIND to detect changes without downloading
+    any file content, making the common no-change case very fast.
+
+    When *update_hash_only* is True, mismatched hashes update the last import's
+    stored hash without re-downloading — useful when migrating to a new hash
+    scheme to avoid a one-time re-import.
+    """
+    import hashlib
+    import shutil
     import zipfile
     from datetime import datetime
 
@@ -198,7 +210,7 @@ def scan_webdav_for_retroarch(webdav_client, user_id):
         return 0
 
     try:
-        files = webdav_client.list(retroarch_path)
+        files = webdav_client.list(retroarch_path, get_info=True)
     except Exception as e:
         logger.warning(
             "Could not list var/retroarch/",
@@ -206,10 +218,11 @@ def scan_webdav_for_retroarch(webdav_client, user_id):
         )
         return 0
 
-    lrtl_basenames = sorted(
-        os.path.basename(fname) for fname in files if fname.lower().endswith(".lrtl")
+    lrtl_files = sorted(
+        [f for f in files if f.get("name", "").lower().endswith(".lrtl")],
+        key=lambda x: x.get("name", ""),
     )
-    if not lrtl_basenames:
+    if not lrtl_files:
         logger.info("No .lrtl files found on webdav", extra={"user_id": user_id})
         return 0
 
@@ -223,14 +236,48 @@ def scan_webdav_for_retroarch(webdav_client, user_id):
         )
         return 0
 
+    # Compute hash from filenames + ETags (no downloads needed)
+    hasher = hashlib.md5()
+    for f in lrtl_files:
+        hasher.update(f.get("name", "").encode())
+        hasher.update((f.get("etag") or f.get("modified") or "").encode())
+    content_hash = hasher.hexdigest()
+
+    # Skip if the last completed import already has this hash
+    last_import = (
+        RetroarchImport.objects.filter(
+            user_id=user_id, processed_finished__isnull=False
+        )
+        .order_by("-processed_finished")
+        .first()
+    )
+    if last_import and last_import.files_hash == content_hash:
+        logger.info(
+            "Retroarch lrtl files unchanged for user, skipping",
+            extra={"user_id": user_id},
+        )
+        return 0
+
+    if update_hash_only and last_import:
+        logger.info(
+            "Updating retroarch files_hash (%s) without re-import",
+            content_hash[:12],
+            extra={"user_id": user_id},
+        )
+        last_import.files_hash = content_hash
+        last_import.save(update_fields=["files_hash"])
+        return 0
+
+    # Something changed — download everything
     download_dir = tempfile.mkdtemp()
     try:
         downloaded = []
-        for basename in lrtl_basenames:
+        for f in lrtl_files:
+            basename = f.get("name")
             dst = os.path.join(download_dir, basename)
             try:
                 webdav_client.download_sync(
-                    remote_path=f"{retroarch_path}/{basename}",
+                    remote_path=f.get("path"),
                     local_path=dst,
                 )
                 downloaded.append(basename)
@@ -240,32 +287,6 @@ def scan_webdav_for_retroarch(webdav_client, user_id):
         if not downloaded:
             return 0
 
-        # Compute content hash of all downloaded files
-        import hashlib
-
-        hasher = hashlib.md5()
-        for basename in downloaded:
-            filepath = os.path.join(download_dir, basename)
-            hasher.update(basename.encode())
-            with open(filepath, "rb") as f:
-                hasher.update(f.read())
-        content_hash = hasher.hexdigest()
-
-        # Skip if the last completed import already has this hash
-        last_import = (
-            RetroarchImport.objects.filter(
-                user_id=user_id, processed_finished__isnull=False
-            )
-            .order_by("-processed_finished")
-            .first()
-        )
-        if last_import and last_import.files_hash == content_hash:
-            logger.info(
-                "Retroarch lrtl files unchanged for user, skipping",
-                extra={"user_id": user_id},
-            )
-            return 0
-
         zip_path = os.path.join(
             download_dir,
             f"retroarch-batch-{datetime.now().strftime('%Y%m%d%H%M%S')}.zip",
@@ -290,8 +311,6 @@ def scan_webdav_for_retroarch(webdav_client, user_id):
         )
         return 1
     finally:
-        import shutil
-
         shutil.rmtree(download_dir, ignore_errors=True)
 
 

vrobbler/apps/scrobbles/management/commands/import_from_webdav.py

@@ -9,13 +9,23 @@ class Command(BaseCommand):
             action="store_true",
             help="Restart failed imports",
         )
+        parser.add_argument(
+            "--update-retroarch-hash",
+            action="store_true",
+            help="Update retroarch files_hash to new ETag-based scheme "
+            "without re-importing (migration helper)",
+        )
 
     def handle(self, *args, **options):
         restart = False
         if options["restart"]:
             restart = True
+        update_hash = options.get("update_retroarch_hash", False)
         ko_count, gpx_count, retro_count, bgstats_count, ebird_count, scale_count = (
-            webdav.import_from_webdav_for_all_users(restart=restart)
+            webdav.import_from_webdav_for_all_users(
+                restart=restart,
+                update_retroarch_hash=update_hash,
+            )
         )
         print(
             f"Started {ko_count} KOReader, {gpx_count} Trail GPX, "