[Bugfix] Fix fallback loading for IndexTTS external models (#6137)

Signed-off-by: boatman <109857087+sphinxkkkbc@users.noreply.github.com>

tests/model_executor/models/indextts2/test_enhanced_codec.py

@@ -82,3 +82,31 @@ def test_model_asset_resolver_supports_native_checkpoints_layout(tmp_path):
     checkpoint.touch()
 
     assert preprocess_utils.resolve_model_file(str(tmp_path), "codec.pth") == str(checkpoint)
+
+
+def test_campplus_falls_back_to_hub_for_local_model_dir(tmp_path, monkeypatch):
+    import huggingface_hub
+
+    from vllm_omni.model_executor.models.indextts2.utils.campplus import dtdnn
+
+    checkpoint = tmp_path / "downloaded-campplus.bin"
+    checkpoint.touch()
+    downloads = []
+
+    class FakeCAMPPlus(torch.nn.Module):
+        def load_state_dict(self, state, strict=True):
+            self.loaded_state = (state, strict)
+
+    monkeypatch.setattr(dtdnn, "CAMPPlus", lambda **_kwargs: FakeCAMPPlus())
+    monkeypatch.setattr(
+        huggingface_hub,
+        "hf_hub_download",
+        lambda repo_id, filename: downloads.append((repo_id, filename)) or str(checkpoint),
+    )
+    monkeypatch.setattr(preprocess_utils.torch, "load", lambda *_args, **_kwargs: {"weight": torch.ones(1)})
+    preprocess_utils._campplus_cache.clear()
+
+    model = preprocess_utils.load_campplus(str(tmp_path), torch.device("cpu"))
+
+    assert isinstance(model, FakeCAMPPlus)
+    assert downloads == [("funasr/campplus", "campplus_cn_common.bin")]

tests/model_executor/models/indextts2/test_s2mel_v2_5.py

@@ -838,6 +838,16 @@ def test_v25_resolved_vocoder_source_is_cached(monkeypatch):
     assert calls == [("/models/indextts25", "fake-bigvgan")]
 
 
+def test_bigvgan_source_falls_back_to_hub_repo_for_local_model_dir(tmp_path):
+    assert (
+        indextts2_s2mel_decoder._resolve_bigvgan_source(
+            str(tmp_path),
+            "nvidia/bigvgan_v2_22khz_80band_256x",
+        )
+        == "nvidia/bigvgan_v2_22khz_80band_256x"
+    )
+
+
 def test_stage1_preload_does_not_swallow_cuda_runtime_failure(monkeypatch):
     decoder = object.__new__(IndexTTS2S2MelDecoder)
     torch.nn.Module.__init__(decoder)

vllm_omni/model_executor/models/indextts2/indextts2_s2mel_decoder.py

@@ -78,8 +78,6 @@ def _resolve_bigvgan_source(model_path: str, vocoder_name: str) -> str:
     )
     if local_dir is not None:
         return local_dir
-    if os.path.isdir(model_path):
-        raise FileNotFoundError(f"IndexTTS BigVGAN assets are missing from local bundle {model_path!r}")
     return vocoder_name
 
 

vllm_omni/model_executor/models/indextts2/preprocess_utils.py

@@ -102,9 +102,6 @@ def load_wav2vec2(model_path: str, device: torch.device):
         except Exception as exc:
             raise RuntimeError(f"Failed to load local IndexTTS Wav2Vec2-BERT assets from {local_dir!r}") from exc
 
-    if local_dir is None and os.path.isdir(model_path):
-        raise FileNotFoundError(f"IndexTTS Wav2Vec2-BERT assets are missing from local bundle {model_path!r}")
-
     # Try a remote model subfolder, then the public base model.
     try:
         if model is None or processor is None:
@@ -173,8 +170,6 @@ def load_semantic_codec(
         state = torch.load(ckpt_path, map_location="cpu", weights_only=True)
         codec.load_state_dict(state, strict=False)
     else:
-        if os.path.isdir(model_path):
-            raise FileNotFoundError(f"IndexTTS RepCodec checkpoint is missing from local bundle {model_path!r}")
         import safetensors.torch
         from huggingface_hub import hf_hub_download
 
@@ -203,8 +198,6 @@ def load_campplus(model_path: str, device: torch.device):
         if ckpt_path is not None:
             break
     if ckpt_path is None:
-        if os.path.isdir(model_path):
-            raise FileNotFoundError(f"IndexTTS CAMPPlus checkpoint is missing from local bundle {model_path!r}")
         from huggingface_hub import hf_hub_download
 
         ckpt_path = hf_hub_download("funasr/campplus", filename="campplus_cn_common.bin")