Python entry-point for CustomLLM subclasses (#15881)

* load entrypoints

* mock loading entry-point in pyproject.toml

* simpler group name

* create CustomLLM subclass instance after load

Author: AlbertDeFusco

litellm/utils.py

@@ -36,6 +36,7 @@
 from dataclasses import dataclass, field
 from functools import lru_cache, wraps
 from importlib import resources
+from importlib.metadata import entry_points
 from inspect import iscoroutine
 from io import StringIO
 from os.path import abspath, dirname, join
@@ -385,10 +386,22 @@ def print_verbose(
 
 ####### CLIENT ###################
 # make it easy to log if completion/embedding runs succeeded or failed + see what happened | Non-Blocking
+def load_custom_provider_entrypoints():
+    found_entry_points = tuple(entry_points().select(group="litellm"))  # type: ignore
+    for entry_point in found_entry_points:
+        # types are ignored because of circular dependency issues importing CustomLLM and CustomLLMItem
+        HandlerClass = entry_point.load()
+        handler = HandlerClass()
+        provider = {"provider": entry_point.name, "custom_handler": handler}
+        litellm.custom_provider_map.append(provider)  # type: ignore
+
+
 def custom_llm_setup():
     """
     Add custom_llm provider to provider list
     """
+    load_custom_provider_entrypoints()
+
     for custom_llm in litellm.custom_provider_map:
         if custom_llm["provider"] not in litellm.provider_list:
             litellm.provider_list.append(custom_llm["provider"])

tests/local_testing/test_custom_llm.py

@@ -10,6 +10,7 @@
 
 import openai
 import pytest
+from pytest_mock import MockerFixture
 
 sys.path.insert(
     0, os.path.abspath("../..")
@@ -536,4 +537,47 @@ async def test_simple_aembedding():
         "object": "embedding",
         "embedding": [0.1, 0.2, 0.3],
         "index": 1,
-    }
+    }
+
+
+def test_custom_llm_provider_entrypoint(mocker: MockerFixture):
+    # This test mocks the use of entry-points in pyproject.toml:
+    #   [project.entry-point.litellm]
+    #   custom_llm = <module>:MyCustomLLM
+    #   another-custom-llm = <module>:AnotherCustomLLM
+
+    from litellm.utils import custom_llm_setup
+
+    class AnotherCustomLLM(CustomLLM):
+        pass
+
+    providers = {
+        "custom_llm": MyCustomLLM,
+        "another-custom-llm": AnotherCustomLLM
+    }
+
+    def load(self):
+        return providers[self.name]
+
+    mocker.patch("importlib.metadata.EntryPoint.load", load)
+    from importlib.metadata import EntryPoints, EntryPoint
+
+    entry_points = EntryPoints([
+        EntryPoint(group="litellm", name="custom_llm", value="package.module:MyCustomLLM"),
+        EntryPoint(group="litellm", name="another-custom-llm", value="package.module:AnotherCustomLLM"),
+    ])
+    mocked = mocker.patch("litellm.utils.entry_points")
+    mocked.return_value = entry_points
+
+    assert litellm.custom_provider_map == []
+    assert litellm._custom_providers == []
+
+    custom_llm_setup()
+
+    assert litellm._custom_providers == ['custom_llm', 'another-custom-llm']
+
+    assert litellm.custom_provider_map[0]["provider"] == "custom_llm"
+    assert isinstance(litellm.custom_provider_map[0]["custom_handler"], CustomLLM)
+
+    assert litellm.custom_provider_map[1]["provider"] == "another-custom-llm"
+    assert isinstance(litellm.custom_provider_map[1]["custom_handler"], AnotherCustomLLM)