fix: allow lookup of models registered at runtime

adds tests for ModelRegistryHelper to stabilize behavior

tests/unit/providers/utils/test_model_registry.py

@@ -0,0 +1,126 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+
+#
+# ModelRegistryHelper provides mixin functionality for registering and
+# unregistering models. It maintains a mapping of model ID / aliases to
+# provider model IDs.
+#
+# Test cases -
+#  - Looking up an alias that does not exist should return None.
+#  - Registering a model + provider ID should add the model to the registry. If provider ID is known.
+#  - Registering an existing model should return an error.
+#  - Unregistering a model should remove it from the registry.
+#  - Unregistering a model that does not exist should return an error.
+#  - Models can be registered during initialization or via register_model.
+#
+# Questions -
+#  - Should we be allowed to register models w/o provider model IDs? No.
+#    According to POST /v1/models, required params are
+#      - identifier
+#      - provider_resource_id
+#      - provider_id
+#      - type
+#      - metadata
+#      - model_type
+#
+#  TODO: llama_model functionality
+#
+
+import pytest
+
+from llama_stack.apis.models.models import Model
+from llama_stack.providers.utils.inference.model_registry import ModelRegistryHelper, ProviderModelEntry
+
+
+@pytest.fixture
+def known_model() -> Model:
+    return Model(
+        provider_id="provider",
+        identifier="known-model",
+        provider_resource_id="known-provider-id",
+    )
+
+
+@pytest.fixture
+def known_provider_model(known_model: Model) -> ProviderModelEntry:
+    return ProviderModelEntry(
+        provider_model_id=known_model.provider_resource_id,
+        # aliases=[],
+    )
+
+
+@pytest.fixture
+def unknown_model() -> Model:
+    return Model(
+        provider_id="provider",
+        identifier="unknown-model",
+        provider_resource_id="unknown-provider-id",
+    )
+
+
+@pytest.fixture
+def helper(known_provider_model: ProviderModelEntry) -> ModelRegistryHelper:
+    return ModelRegistryHelper([known_provider_model])
+
+
+@pytest.mark.asyncio
+async def test_lookup_unknown_model(helper: ModelRegistryHelper, unknown_model: Model) -> None:
+    assert helper.get_provider_model_id(unknown_model.model_id) is None
+
+
+@pytest.mark.asyncio
+async def test_register_unknown_provider_model(helper: ModelRegistryHelper, unknown_model: Model) -> None:
+    with pytest.raises(ValueError):
+        await helper.register_model(unknown_model)
+
+
+@pytest.mark.asyncio
+async def test_register_model(helper: ModelRegistryHelper, known_model: Model) -> None:
+    assert helper.get_provider_model_id(known_model.model_id) is None
+    await helper.register_model(known_model)
+    assert helper.get_provider_model_id(known_model.model_id) == known_model.provider_resource_id
+
+
+@pytest.mark.asyncio
+async def test_register_model_existing(helper: ModelRegistryHelper, known_model: Model) -> None:
+    await helper.register_model(known_model)
+    with pytest.raises(ValueError):
+        await helper.register_model(known_model)
+
+
+@pytest.mark.asyncio
+async def test_unregister_model(helper: ModelRegistryHelper, known_model: Model) -> None:
+    await helper.register_model(known_model)
+    assert helper.get_provider_model_id(known_model.model_id) == known_model.provider_model_id
+    await helper.unregister_model(known_model.model_id)
+    assert helper.get_provider_model_id(known_model.model_id) is None
+
+
+@pytest.mark.asyncio
+async def test_unregister_unknown_model(helper: ModelRegistryHelper, unknown_model: Model) -> None:
+    with pytest.raises(ValueError):
+        await helper.unregister_model(unknown_model.model_id)
+
+
+@pytest.mark.asyncio
+async def test_register_model_during_init(helper: ModelRegistryHelper, known_model: Model) -> None:
+    assert helper.get_provider_model_id(known_model.provider_resource_id) == known_model.provider_model_id
+
+
+@pytest.mark.asyncio
+async def test_register_model_existing_from_init(helper: ModelRegistryHelper, known_model: Model) -> None:
+    assert helper.get_provider_model_id(known_model.provider_resource_id) == known_model.provider_model_id
+    with pytest.raises(ValueError):
+        known_model.identifier = known_model.provider_resource_id
+        await helper.register_model(known_model)
+
+
+@pytest.mark.asyncio
+async def test_unregister_model_during_init(helper: ModelRegistryHelper, known_model: Model) -> None:
+    assert helper.get_provider_model_id(known_model.provider_resource_id) == known_model.provider_model_id
+    await helper.unregister_model(known_model.provider_resource_id)
+    assert helper.get_provider_model_id(known_model.provider_resource_id) is None