Added class for loading locally saved model

doc/changes/changes_0.8.0.md

@@ -11,6 +11,7 @@ This release added the get_language_definition function to the LanguageContainer
 
  - #174: Added get_language_definition to the language container deployer
 
+
 ### Bug Fixes
 
  - n/a

doc/changes/changes_0.9.0.md

@@ -9,7 +9,7 @@ T.B.D
 
 ### Features
 
- - n/a
+- #145: Added load function for loading local models
 
 ### Bug Fixes
 

exasol_transformers_extension/utils/load_local_model.py

@@ -0,0 +1,66 @@
+import torch
+import transformers.pipelines
+from typing import Optional
+from pathlib import Path
+from exasol_transformers_extension.utils.model_factory_protocol import ModelFactoryProtocol
+
+
+class LoadLocalModel:
+    """
+    Class for loading locally saved models and tokenizers. Also stores information regarding the model and pipeline.
+
+    :pipeline_factory:      a function to create a transformers pipeline
+    :task_name:             name of the current task
+    :device:                device to be used for pipeline creation
+    :_base_model_factory:    a ModelFactoryProtocol for creating the loaded model
+    :_tokenizer_factory:     a ModelFactoryProtocol for creating the loaded tokenizer
+    """
+    def __init__(self,
+                 pipeline_factory,
+                 task_name: str,
+                 device: str,
+                 base_model_factory: ModelFactoryProtocol,
+                 tokenizer_factory: ModelFactoryProtocol
+                 ):
+        self.pipeline_factory = pipeline_factory
+        self.task_name = task_name
+        self.device = device
+        self._base_model_factory = base_model_factory
+        self._tokenizer_factory = tokenizer_factory
+        self._loaded_model_key = None
+
+    @property
+    def loaded_model_key(self):
+        """Get the current loaded_model_key."""
+        return self._loaded_model_key
+
+    def load_models(self,
+                    model_path: Path,
+                    current_model_key: str
+                    ) -> transformers.pipelines.Pipeline:
+        """
+        Loads a locally saved model and tokenizer from "cache_dir / "pretrained" / model_name".
+        Returns new pipeline corresponding to the model and task.
+
+        :model_path:            location of the saved model and tokenizer
+        :current_model_key:     key of the model to be loaded
+        """
+
+        loaded_model = self._base_model_factory.from_pretrained(str(model_path))
+        loaded_tokenizer = self._tokenizer_factory.from_pretrained(str(model_path))
+
+        last_created_pipeline = self.pipeline_factory(
+            self.task_name,
+            model=loaded_model,
+            tokenizer=loaded_tokenizer,
+            device=self.device,
+            framework="pt")
+        self._loaded_model_key = current_model_key
+        return last_created_pipeline
+
+    def clear_device_memory(self):
+        """
+        Delete models and free device memory
+        """
+        torch.cuda.empty_cache()
+

exasol_transformers_extension/utils/model_factory_protocol.py

@@ -1,5 +1,5 @@
 from pathlib import Path
-from typing import Protocol, Union, runtime_checkable
+from typing import Protocol, Union, runtime_checkable, Optional
 
 import transformers
 
@@ -9,8 +9,17 @@ class ModelFactoryProtocol(Protocol):
     """
     Protocol for better type hints.
     """
-    def from_pretrained(self, model_name: str, cache_dir: Path, use_auth_token: str) -> transformers.PreTrainedModel:
+    def from_pretrained(self, model_name: str, cache_dir: Optional[Path]=None, use_auth_token: Optional[str]=None) \
+            -> transformers.PreTrainedModel:
+        """
+        Either downloads a model from Huggingface Hub(all parameters required),
+        or loads a locally saved model from file (only requires filepath)
+
+        :model_name:        model name, or path to locally saved model files
+        :cache_dir:         optional. Path where downloaded model should be cached
+        :use_auth_token:    optional. token for Huggingface hub private models
+        """
         pass
 
     def save_pretrained(self, save_directory: Union[str, Path]):
-        pass
+        pass

tests/integration_tests/without_db/utils/test_load_local_model.py

@@ -0,0 +1,83 @@
+from pathlib import Path, PurePosixPath
+from transformers import AutoModel, AutoTokenizer, pipeline
+import tarfile
+
+from exasol_transformers_extension.utils.load_local_model import LoadLocalModel
+from exasol_transformers_extension.utils.model_factory_protocol import ModelFactoryProtocol
+from exasol_transformers_extension.utils.huggingface_hub_bucketfs_model_transfer_sp import \
+    HuggingFaceHubBucketFSModelTransferSPFactory
+from exasol_bucketfs_utils_python.localfs_mock_bucketfs_location import \
+    LocalFSMockBucketFSLocation
+
+from tests.utils.parameters import model_params
+
+import tempfile
+
+
+class TestSetup:
+    def __init__(self):
+
+        self.base_model_factory: ModelFactoryProtocol = AutoModel
+        self.tokenizer_factory: ModelFactoryProtocol = AutoTokenizer
+
+        self.token = "token"
+        model_params_ = model_params.tiny_model
+        self.model_name = model_params_
+
+        self.mock_current_model_key = None
+        test_pipeline = pipeline
+        self.loader = LoadLocalModel(
+                                    test_pipeline,
+                                    task_name="token-classification",
+                                    device="cpu",
+                                    base_model_factory=self.base_model_factory,
+                                    tokenizer_factory=self.tokenizer_factory
+                                    )
+
+
+def download_model_with_huggingface_transfer(test_setup, mock_bucketfs_location):
+    model_transfer_factory = HuggingFaceHubBucketFSModelTransferSPFactory()
+    downloader = model_transfer_factory.create(bucketfs_location=mock_bucketfs_location,
+                                               model_name=test_setup.model_name,
+                                               model_path=Path("cached_files"),
+                                               token="")
+    downloader.download_from_huggingface_hub(test_setup.base_model_factory)
+    downloader.download_from_huggingface_hub(test_setup.tokenizer_factory)
+    bucketfs_model_path = downloader.upload_to_bucketfs()
+
+    with tarfile.open(mock_bucketfs_location.base_path / bucketfs_model_path) as tar:
+        tar.extractall(path=mock_bucketfs_location.base_path / bucketfs_model_path.parent)
+    return mock_bucketfs_location.base_path / bucketfs_model_path.parent
+
+
+def test_load_local_model():
+    test_setup = TestSetup()
+
+    with tempfile.TemporaryDirectory() as dir:
+        dir_p = Path(dir)
+        model_save_path = dir_p / "pretrained" / test_setup.model_name
+        # download a model
+        model = AutoModel.from_pretrained(test_setup.model_name)
+        tokenizer = AutoTokenizer.from_pretrained(test_setup.model_name)
+        model.save_pretrained(model_save_path)
+        tokenizer.save_pretrained(model_save_path)
+
+        test_setup.loader.load_models(current_model_key=test_setup.mock_current_model_key,
+                                      model_path=dir_p / "pretrained" / test_setup.model_name)
+
+
+def test_load_local_model_with_huggingface_model_transfer():
+    test_setup = TestSetup()
+
+    with tempfile.TemporaryDirectory() as dire:
+        dir_p = Path(dire)
+
+        mock_bucketfs_location = LocalFSMockBucketFSLocation(
+            PurePosixPath(dir_p / "bucket"))
+
+        # download a model
+        downloaded_model_path = download_model_with_huggingface_transfer(
+            test_setup, mock_bucketfs_location)
+
+        test_setup.loader.load_models(current_model_key=test_setup.mock_current_model_key,
+                                      model_path=downloaded_model_path)

tests/unit_tests/utils/test_load_local_model.py

@@ -0,0 +1,41 @@
+import tempfile
+from pathlib import Path
+from typing import Union
+from unittest.mock import create_autospec, MagicMock, call
+
+from exasol_transformers_extension.utils.model_factory_protocol import ModelFactoryProtocol
+from exasol_transformers_extension.utils.load_local_model import LoadLocalModel
+
+
+
+class TestSetup:
+    def __init__(self):
+
+        self.model_factory_mock: Union[ModelFactoryProtocol, MagicMock] = create_autospec(ModelFactoryProtocol)
+        self.tokenizer_factory_mock: Union[ModelFactoryProtocol, MagicMock] = create_autospec(ModelFactoryProtocol)
+        self.token = "token"
+        self.model_name = "model_name"
+        self.mock_current_model_key = "some_key"
+        self.cache_dir = "test/Path"
+
+        mock_pipeline = lambda task_name, model, tokenizer, device, framework: None
+        self.loader = LoadLocalModel(
+                                     mock_pipeline,
+                                     task_name="test_task",
+                                     device=0,
+                                     base_model_factory=self.model_factory_mock,
+                                     tokenizer_factory=self.tokenizer_factory_mock)
+
+
+def test_load_function_call():
+    test_setup = TestSetup()
+    model_save_path = Path(test_setup.cache_dir) / "pretrained" / test_setup.model_name
+
+    test_setup.loader.load_models(current_model_key=test_setup.mock_current_model_key,
+                                    model_path=model_save_path)
+
+    assert test_setup.model_factory_mock.mock_calls == [
+        call.from_pretrained(str(model_save_path))]
+    assert test_setup.tokenizer_factory_mock.mock_calls == [
+        call.from_pretrained(str(model_save_path))]
+