Improve initialization for extra arches

README.md

@@ -56,15 +56,14 @@ Note that `model` is a [`ModelDescriptor`](https://chainner.app/spandrel/#ModelD
 If you are working on a non-commercial open-source project or a private project, you should use `spandrel` and `spandrel_extra_arches` to get everything spandrel has to offer. The `spandrel` package only contains architectures with [permissive and public domain licenses](https://en.wikipedia.org/wiki/Permissive_software_license) (MIT, Apache 2.0, public domain), so it is fit for every use case. Architectures with restrictive licenses (e.g. non-commercial) are implemented in the `spandrel_extra_arches` package.
 
 ```python
-from spandrel import ImageModelDescriptor, MAIN_REGISTRY, ModelLoader
-from spandrel_extra_arches import EXTRA_REGISTRY
-import torch
+import spandrel
+import spandrel_extra_arches
 
 # add extra architectures before `ModelLoader` is used
-MAIN_REGISTRY.add(*EXTRA_REGISTRY)
+spandrel_extra_arches.install()
 
 # load a model from disk
-model = ModelLoader().load_from_file(r"path/to/model.pth")
+model = spandrel.ModelLoader().load_from_file(r"path/to/model.pth")
 
 ... # use model
 ```

libs/spandrel/spandrel/__helpers/registry.py

@@ -15,6 +15,12 @@ class UnsupportedModelError(Exception):
     """
 
 
+class DuplicateArchitectureError(ValueError):
+    """
+    An error that will be thrown by `ArchRegistry` if the same architecture is added twice.
+    """
+
+
 @dataclass(frozen=True)
 class ArchSupport:
     """
@@ -105,30 +111,45 @@ def architectures(
         else:
             raise ValueError(f"Invalid order: {order}")
 
-    def add(self, *architectures: ArchSupport):
+    def add(
+        self,
+        *architectures: ArchSupport,
+        ignore_duplicates: bool = False,
+    ) -> list[ArchSupport]:
         """
         Adds the given architectures to the registry.
 
-        Throws an error if an architecture with the same ID already exists.
+        Throws an error if an architecture with the same ID already exists,
+        unless `ignore_duplicates` is True, in which case the old architecture is retained.
+
         Throws an error if a circular dependency of `before` references is detected.
 
         If an error is thrown, the registry is left unchanged.
+
+        Returns a list of architectures that were added.
         """
 
         new_architectures = list(self._architectures)
         new_by_id = dict(self._by_id)
+        added = []
         for arch in architectures:
             if arch.architecture.id in new_by_id:
-                raise ValueError(f"Duplicate architecture: {arch.architecture.id}")
+                if ignore_duplicates:
+                    continue
+                raise DuplicateArchitectureError(
+                    f"Duplicate architecture: {arch.architecture.id}"
+                )
 
             new_architectures.append(arch)
             new_by_id[arch.architecture.id] = arch
+            added.append(arch)
 
         new_ordered = ArchRegistry._get_ordered(new_architectures)
 
         self._architectures = new_architectures
         self._ordered = new_ordered
         self._by_id = new_by_id
+        return added
 
     @staticmethod
     def _get_ordered(architectures: list[ArchSupport]) -> list[ArchSupport]:

libs/spandrel/spandrel/__init__.py

@@ -20,14 +20,20 @@
     StateDict,
     UnsupportedDtypeError,
 )
-from .__helpers.registry import ArchRegistry, ArchSupport, UnsupportedModelError
+from .__helpers.registry import (
+    ArchRegistry,
+    ArchSupport,
+    DuplicateArchitectureError,
+    UnsupportedModelError,
+)
 
 __all__ = [
     "ArchId",
     "Architecture",
     "ArchRegistry",
     "ArchSupport",
     "canonicalize_state_dict",
+    "DuplicateArchitectureError",
     "ImageModelDescriptor",
     "MAIN_REGISTRY",
     "MaskedImageModelDescriptor",

libs/spandrel_extra_arches/README.md

@@ -20,14 +20,14 @@ pip install spandrel spandrel_extra_arches
 ## Basic usage
 
 ```python
-from spandrel import MAIN_REGISTRY, ModelLoader
-from spandrel_extra_arches import EXTRA_REGISTRY
+import spandrel
+import spandrel_extra_arches
 
 # add extra architectures before `ModelLoader` is used
-MAIN_REGISTRY.add(*EXTRA_REGISTRY)
+spandrel_extra_arches.install()
 
 # load a model from disk
-model = ModelLoader().load_from_file(r"path/to/model.pth")
+model = spandrel.ModelLoader().load_from_file(r"path/to/model.pth")
 
 ... # use model
 ```

libs/spandrel_extra_arches/spandrel_extra_arches/__helper.py

@@ -1,4 +1,10 @@
-from spandrel import ArchRegistry, ArchSupport
+from __future__ import annotations
+
+from spandrel import (
+    MAIN_REGISTRY,
+    ArchRegistry,
+    ArchSupport,
+)
 
 from .architectures import (
     MAT,
@@ -27,3 +33,20 @@
     ArchSupport.from_architecture(MPRNet.MPRNetArch()),
     ArchSupport.from_architecture(MIRNet2.MIRNet2Arch()),
 )
+
+
+def install(*, ignore_duplicates: bool = False) -> list[ArchSupport]:
+    """
+    Try to install the extra architectures into the main registry.
+
+    If `ignore_duplicates` is True, the function will not raise an error
+    if the installation fails due to any of the architectures having already
+    been installed (but they won't be replaced by ones from this package).
+    """
+    return MAIN_REGISTRY.add(*EXTRA_REGISTRY, ignore_duplicates=ignore_duplicates)
+
+
+__all__ = [
+    "EXTRA_REGISTRY",
+    "install",
+]

libs/spandrel_extra_arches/spandrel_extra_arches/__init__.py

@@ -1,5 +1,8 @@
-from .__helper import EXTRA_REGISTRY
+from .__helper import EXTRA_REGISTRY, install
 
 __version__ = "0.1.1"
 
-__all__ = ["EXTRA_REGISTRY"]
+__all__ = [
+    "EXTRA_REGISTRY",
+    "install",
+]

scripts/dump_state_dict.py

@@ -54,14 +54,14 @@
     sys.path.insert(0, __file__ + "/../../libs/spandrel")
     sys.path.insert(0, __file__ + "/../../libs/spandrel_extra_arches")
 
-    from spandrel import MAIN_REGISTRY, ModelLoader  # noqa: E402
-    from spandrel_extra_arches import EXTRA_REGISTRY  # noqa: E402
+    import spandrel_extra_arches  # noqa: E402
+    from spandrel import ModelLoader  # noqa: E402
 except ImportError:
     print("Unable to import spandrel.")
     print("Follow the contributing guide to set up editable installs.")
     raise
 
-MAIN_REGISTRY.add(*EXTRA_REGISTRY)
+spandrel_extra_arches.install()
 
 State = Dict[str, object]
 

tests/__snapshots__/test_registry.ambr

@@ -1,9 +1,9 @@
 # serializer version: 1
 # name: test_registry_add_invalid
-  ValueError('Duplicate architecture: b')
+  DuplicateArchitectureError('Duplicate architecture: b')
 # ---
 # name: test_registry_add_invalid.1
-  ValueError('Duplicate architecture: test')
+  DuplicateArchitectureError('Duplicate architecture: test')
 # ---
 # name: test_registry_add_invalid.2
   ValueError('Circular dependency in architecture detection: 1 -> 2 -> 1')

tests/util.py

@@ -29,8 +29,8 @@
 from bs4 import BeautifulSoup, Tag
 from syrupy.filters import props
 
+import spandrel_extra_arches
 from spandrel import (
-    MAIN_REGISTRY,
     Architecture,
     ImageModelDescriptor,
     ModelDescriptor,
@@ -40,9 +40,13 @@
 )
 from spandrel.__helpers.model_descriptor import StateDict
 from spandrel.util import KeyCondition
-from spandrel_extra_arches import EXTRA_REGISTRY
 
-MAIN_REGISTRY.add(*EXTRA_REGISTRY)
+# The asserts check that the install function first does return
+# the newly installed architectures and then does not return them
+# when requested to ignore duplicates.
+_installed_extras = spandrel_extra_arches.install()
+assert len(_installed_extras) > 0
+assert len(spandrel_extra_arches.install(ignore_duplicates=True)) == 0
 
 TEST_DIR = Path("./tests/").resolve()
 MODEL_DIR = TEST_DIR / "models"