Fixing the download strategy for ibm-fms (#1917)

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Fixes # (issue)


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server/text_generation_server/cli.py

@@ -154,31 +154,27 @@ def download_weights(
         try:
             import json
 
-            medusa_head = hf_hub_download(
-                model_id, revision=revision, filename="medusa_lm_head.safetensors"
-            )
-            medusa_config = hf_hub_download(
+            config = hf_hub_download(
                 model_id, revision=revision, filename="config.json"
             )
-            with open(medusa_config, "r") as f:
+            with open(config, "r") as f:
                 config = json.load(f)
 
-            model_id = config["base_model_name_or_path"]
-            revision = "main"
-            try:
-                utils.weight_files(model_id, revision, extension)
-                logger.info(
-                    f"Files for parent {model_id} are already present on the host. "
-                    "Skipping download."
-                )
-                return
-            # Local files not found
-            except (
-                utils.LocalEntryNotFoundError,
-                FileNotFoundError,
-                utils.EntryNotFoundError,
-            ):
-                pass
+            base_model_id = config.get("base_model_name_or_path", None)
+            if base_model_id and base_model_id != model_id:
+                try:
+                    logger.info(f"Downloading parent model {base_model_id}")
+                    download_weights(
+                        model_id=base_model_id,
+                        revision="main",
+                        extension=extension,
+                        auto_convert=auto_convert,
+                        logger_level=logger_level,
+                        json_output=json_output,
+                        trust_remote_code=trust_remote_code,
+                    )
+                except Exception:
+                    pass
         except (utils.LocalEntryNotFoundError, utils.EntryNotFoundError):
             pass
 
@@ -195,31 +191,6 @@ def download_weights(
             if not extension == ".safetensors" or not auto_convert:
                 raise e
 
-    elif (Path(model_id) / "medusa_lm_head.safetensors").exists():
-        # Try to load as a local Medusa model
-        try:
-            import json
-
-            medusa_head = Path(model_id) / "medusa_lm_head.safetensors"
-            medusa_config = Path(model_id) / "config.json"
-            with open(medusa_config, "r") as f:
-                config = json.load(f)
-
-            model_id = config["base_model_name_or_path"]
-            revision = "main"
-            try:
-                utils.weight_files(model_id, revision, extension)
-                logger.info(
-                    f"Files for parent {model_id} are already present on the host. "
-                    "Skipping download."
-                )
-                return
-            # Local files not found
-            except (utils.LocalEntryNotFoundError, utils.EntryNotFoundError):
-                pass
-        except (utils.LocalEntryNotFoundError, utils.EntryNotFoundError):
-            pass
-
     elif (Path(model_id) / "adapter_config.json").exists():
         # Try to load as a local PEFT model
         try:
@@ -230,14 +201,43 @@ def download_weights(
             return
         except (utils.LocalEntryNotFoundError, utils.EntryNotFoundError):
             pass
+    elif (Path(model_id) / "config.json").exists():
+        # Try to load as a local Medusa model
+        try:
+            import json
+
+            config = Path(model_id) / "config.json"
+            with open(config, "r") as f:
+                config = json.load(f)
+
+            base_model_id = config.get("base_model_name_or_path", None)
+            if base_model_id:
+                try:
+                    logger.info(f"Downloading parent model {base_model_id}")
+                    download_weights(
+                        model_id=base_model_id,
+                        revision="main",
+                        extension=extension,
+                        auto_convert=auto_convert,
+                        logger_level=logger_level,
+                        json_output=json_output,
+                        trust_remote_code=trust_remote_code,
+                    )
+                except Exception:
+                    pass
+        except (utils.LocalEntryNotFoundError, utils.EntryNotFoundError):
+            pass
 
     # Try to see if there are local pytorch weights
     try:
         # Get weights for a local model, a hub cached model and inside the WEIGHTS_CACHE_OVERRIDE
-        local_pt_files = utils.weight_files(model_id, revision, ".bin")
+        try:
+            local_pt_files = utils.weight_files(model_id, revision, ".bin")
+        except Exception:
+            local_pt_files = utils.weight_files(model_id, revision, ".pt")
 
     # No local pytorch weights
-    except utils.LocalEntryNotFoundError:
+    except (utils.LocalEntryNotFoundError, utils.EntryNotFoundError):
         if extension == ".safetensors":
             logger.warning(
                 f"No safetensors weights found for model {model_id} at revision {revision}. "

server/text_generation_server/utils/hub.py

@@ -40,7 +40,6 @@ def _weight_hub_files_from_model_info(
         and "arguments" not in s.rfilename
         and "args" not in s.rfilename
         and "training" not in s.rfilename
-        and "medusa_lm_head" not in s.rfilename
     ]
 
 
@@ -57,7 +56,6 @@ def _weight_files_from_dir(d: Path, extension: str) -> List[str]:
         and "args" not in f
         and "adapter" not in f
         and "training" not in f
-        and "medusa_lm_head" not in f
     ]
     return filenames