add checking for imports

src/diffusers/__init__.py

@@ -4,6 +4,8 @@
     is_onnx_available,
     is_scipy_available,
     is_torch_available,
+    is_inflect_available,
+    is_torch_geometric_available,
     is_transformers_available,
     is_unidecode_available,
 )
@@ -83,3 +85,9 @@
     from .pipelines import FlaxStableDiffusionPipeline
 else:
     from .utils.dummy_flax_and_transformers_objects import *  # noqa F403
+    from .utils.dummy_transformers_objects import *
+
+if is_torch_geometric_available():
+    from .models import MoleculeGNN
+else:
+    from .utils.dummy_torch_geometric_objects import *

src/diffusers/utils/__init__.py

@@ -54,3 +54,148 @@
 DIFFUSERS_CACHE = default_cache_path
 DIFFUSERS_DYNAMIC_MODULE_NAME = "diffusers_modules"
 HF_MODULES_CACHE = os.getenv("HF_MODULES_CACHE", os.path.join(hf_cache_home, "modules"))
+<<<<<<< HEAD
+=======
+
+
+_transformers_available = importlib.util.find_spec("transformers") is not None
+try:
+    _transformers_version = importlib_metadata.version("transformers")
+    logger.debug(f"Successfully imported transformers version {_transformers_version}")
+except importlib_metadata.PackageNotFoundError:
+    _transformers_available = False
+
+
+_inflect_available = importlib.util.find_spec("inflect") is not None
+try:
+    _inflect_version = importlib_metadata.version("inflect")
+    logger.debug(f"Successfully imported inflect version {_inflect_version}")
+except importlib_metadata.PackageNotFoundError:
+    _inflect_available = False
+
+
+_unidecode_available = importlib.util.find_spec("unidecode") is not None
+try:
+    _unidecode_version = importlib_metadata.version("unidecode")
+    logger.debug(f"Successfully imported unidecode version {_unidecode_version}")
+except importlib_metadata.PackageNotFoundError:
+    _unidecode_available = False
+
+
+_modelcards_available = importlib.util.find_spec("modelcards") is not None
+try:
+    _modelcards_version = importlib_metadata.version("modelcards")
+    logger.debug(f"Successfully imported modelcards version {_modelcards_version}")
+except importlib_metadata.PackageNotFoundError:
+    _modelcards_available = False
+
+_torch_scatter_available = importlib.util.find_spec("torch_scatter") is not None
+try:
+    _torch_scatter_version = importlib_metadata.version("torch_scatter")
+    logger.debug(f"Successfully imported torch_scatter version {_torch_scatter_version}")
+except importlib_metadata.PackageNotFoundError:
+    _torch_scatter_available = False
+
+_torch_scatter_available = importlib.util.find_spec("torch_geometric") is not None
+try:
+    _torch_geometric_version = importlib_metadata.version("torch_geometric")
+    logger.debug(f"Successfully imported torch_geometric version {_torch_geometric_version}")
+except importlib_metadata.PackageNotFoundError:
+    _torch_geometric_available = False
+
+
+def is_transformers_available():
+    return _transformers_available
+
+
+def is_inflect_available():
+    return _inflect_available
+
+
+def is_unidecode_available():
+    return _unidecode_available
+
+
+def is_modelcards_available():
+    return _modelcards_available
+
+
+def is_torch_scatter_available():
+    return _torch_scatter_available
+
+
+def is_torch_geometric_available():
+    # the model source of the Molecule Generation GNN requires a specific torch geometric version
+    # for more info, see the original repo https://github.com/MinkaiXu/GeoDiff or our colab in readme
+    return _torch_geometric_version == "1.7.2"
+
+
+class RepositoryNotFoundError(HTTPError):
+    """
+    Raised when trying to access a hf.co URL with an invalid repository name, or with a private repo name the user does
+    not have access to.
+    """
+
+
+class EntryNotFoundError(HTTPError):
+    """Raised when trying to access a hf.co URL with a valid repository and revision but an invalid filename."""
+
+
+class RevisionNotFoundError(HTTPError):
+    """Raised when trying to access a hf.co URL with a valid repository but an invalid revision."""
+
+
+TRANSFORMERS_IMPORT_ERROR = """
+{0} requires the transformers library but it was not found in your environment. You can install it with pip: `pip
+install transformers`
+"""
+
+
+UNIDECODE_IMPORT_ERROR = """
+{0} requires the unidecode library but it was not found in your environment. You can install it with pip: `pip install
+Unidecode`
+"""
+
+
+INFLECT_IMPORT_ERROR = """
+{0} requires the inflect library but it was not found in your environment. You can install it with pip: `pip install
+inflect`
+"""
+
+TORCH_GEOMETRIC_IMPORT_ERROR = """
+{0} requires version 1.7.2 of torch_geometric but it was not found in your environment. You can install it with conda:
+`conda install -c rusty1s pytorch-geometric=1.7.2`, given pytorch 1.8
+"""
+
+
+BACKENDS_MAPPING = OrderedDict(
+    [
+        ("transformers", (is_transformers_available, TRANSFORMERS_IMPORT_ERROR)),
+        ("unidecode", (is_unidecode_available, UNIDECODE_IMPORT_ERROR)),
+        ("inflect", (is_inflect_available, INFLECT_IMPORT_ERROR)),
+    ]
+)
+
+
+def requires_backends(obj, backends):
+    if not isinstance(backends, (list, tuple)):
+        backends = [backends]
+
+    name = obj.__name__ if hasattr(obj, "__name__") else obj.__class__.__name__
+    checks = (BACKENDS_MAPPING[backend] for backend in backends)
+    failed = [msg.format(name) for available, msg in checks if not available()]
+    if failed:
+        raise ImportError("".join(failed))
+
+
+class DummyObject(type):
+    """
+    Metaclass for the dummy objects. Any class inheriting from it will return the ImportError generated by
+    `requires_backend` each time a user tries to access any method of that class.
+    """
+
+    def __getattr__(cls, key):
+        if key.startswith("_"):
+            return super().__getattr__(cls, key)
+        requires_backends(cls, cls._backends)
+>>>>>>> bf87817 (add checking for imports)

src/diffusers/utils/dummy_torch_geometric_objects.py

@@ -0,0 +1,10 @@
+# This file is autogenerated by the command `make fix-copies`, do not edit.
+# flake8: noqa
+from ..utils import DummyObject, requires_backends
+
+
+class MoleculeGNN(metaclass=DummyObject):
+    _backends = ["torch_geometric"]
+
+    def __init__(self, *args, **kwargs):
+        requires_backends(self, ["torch_geometric"])

tests/test_modeling_utils.py

@@ -31,14 +31,21 @@
     DDPMScheduler,
     LDMPipeline,
     LDMTextToImagePipeline,
-    MoleculeGNN,
     PNDMPipeline,
     PNDMScheduler,
     ScoreSdeVePipeline,
     ScoreSdeVeScheduler,
     UNet2DModel,
     VQModel,
 )
+from diffusers.utils import is_torch_geometric_available
+
+
+if is_torch_geometric_available():
+    from diffusers import MoleculeGNN
+else:
+    from diffusers.utils.dummy_torch_geometric_objects import *
+
 from diffusers.configuration_utils import ConfigMixin, register_to_config
 from diffusers.pipeline_utils import DiffusionPipeline
 from diffusers.testing_utils import floats_tensor, slow, torch_device