Add retry logic and verification for model downloads

app.py

@@ -2,6 +2,7 @@ import os
 import sys
 import shutil
 import subprocess
+import time
 from pathlib import Path
 
 # Hugging Face Spaces / CPU-only environment setup
@@ -17,6 +18,30 @@ def run(cmd, cwd=None):
     print(">>>", " ".join(map(str, cmd)), flush=True)
     subprocess.check_call(cmd, cwd=cwd)
 
+def download_with_retry(repo_id, filename, local_dir, max_retries=3):
+    """Download with retry logic"""
+    from huggingface_hub import hf_hub_download
+    for attempt in range(max_retries):
+        try:
+            print(f"Downloading {filename} from {repo_id} (attempt {attempt+1}/{max_retries})...", flush=True)
+            hf_hub_download(
+                repo_id=repo_id,
+                filename=filename,
+                local_dir=local_dir,
+                local_dir_use_symlinks=False,
+            )
+            target = Path(local_dir) / filename
+            if target.exists() and target.stat().st_size > 1000:
+                print(f"✓ {filename} downloaded successfully ({target.stat().st_size} bytes)", flush=True)
+                return True
+            else:
+                print(f"✗ {filename} download failed: file too small or missing", flush=True)
+        except Exception as e:
+            print(f"✗ Attempt {attempt+1} failed: {e}", flush=True)
+        if attempt < max_retries - 1:
+            time.sleep(5)
+    return False
+
 # 1. Guarantee RVC existence regardless of build SDK
 if not (RVC_DIR / "webui.py").exists():
     print("RVC missing or incomplete. Performing clean clone...", flush=True)
@@ -46,24 +71,30 @@ for asset_dir in [
     asset_dir.mkdir(parents=True, exist_ok=True)
 
 # 4. Download OldChineseMan RVC model from model repo
-from huggingface_hub import hf_hub_download
-
 model_repo = "jacky3102/OldChineseMan_RVC"
 weights_dir = RVC_DIR / "assets" / "weights"
 indices_dir = RVC_DIR / "assets" / "indices"
 
-for fname in ["OldChineseMan.pth", "added_IVF24_Flat_nprobe_1_OldChineseMan_v2.index"]:
-    target = weights_dir / fname if fname.endswith(".pth") else indices_dir / fname
-    if not target.exists():
-        print(f"Downloading {fname} from {model_repo}...", flush=True)
-        hf_hub_download(
-            repo_id=model_repo,
-            filename=fname,
-            local_dir=weights_dir if fname.endswith(".pth") else indices_dir,
-            local_dir_use_symlinks=False,
-        )
+files_to_download = [
+    ("OldChineseMan.pth", weights_dir),
+    ("added_IVF24_Flat_nprobe_1_OldChineseMan_v2.index", indices_dir),
+]
+
+print("=== Downloading RVC model files ===", flush=True)
+all_ok = True
+for fname, target_dir in files_to_download:
+    target = target_dir / fname
+    if target.exists() and target.stat().st_size > 1000:
+        print(f"✓ {fname} already exists ({target.stat().st_size} bytes)", flush=True)
     else:
-        print(f"{fname} already exists, skipping.", flush=True)
+        if not download_with_retry(model_repo, fname, target_dir):
+            print(f"✗ FAILED to download {fname}", flush=True)
+            all_ok = False
+
+if not all_ok:
+    print("⚠ Some model files failed to download. Inference may fail.", flush=True)
+else:
+    print("=== All model files ready ===", flush=True)
 
 # 5. Launch RVC WebUI (webui.py is the new entry point)
 run([