(refactor) litellm.Router client initialization utils (#6394)

* refactor InitalizeOpenAISDKClient

* use helper func for _should_create_openai_sdk_client_for_model

* use static methods for set client on litellm router

* reduce LOC in _get_client_initialization_params

* fix _should_create_openai_sdk_client_for_model

* code quality fix

* test test_should_create_openai_sdk_client_for_model

* test test_get_client_initialization_params_openai

* fix mypy linting errors

* fix OpenAISDKClientInitializationParams

* test_get_client_initialization_params_all_env_vars

* test_get_client_initialization_params_azure_ai_studio_mistral

* test_get_client_initialization_params_default_values

* fix _get_client_initialization_params

litellm/router.py

@@ -63,10 +63,7 @@
     _get_router_metadata_variable_name,
     replace_model_in_jsonl,
 )
-from litellm.router_utils.client_initalization_utils import (
-    set_client,
-    should_initialize_sync_client,
-)
+from litellm.router_utils.client_initalization_utils import InitalizeOpenAISDKClient
 from litellm.router_utils.cooldown_cache import CooldownCache
 from litellm.router_utils.cooldown_callbacks import router_cooldown_event_callback
 from litellm.router_utils.cooldown_handlers import (
@@ -3951,7 +3948,7 @@ def _add_deployment(self, deployment: Deployment) -> Deployment:
             raise Exception(f"Unsupported provider - {custom_llm_provider}")
 
         # init OpenAI, Azure clients
-        set_client(
+        InitalizeOpenAISDKClient.set_client(
             litellm_router_instance=self, model=deployment.to_json(exclude_none=True)
         )
 
@@ -4661,7 +4658,9 @@ def _get_client(self, deployment, kwargs, client_type=None):
                     """
                     Re-initialize the client
                     """
-                    set_client(litellm_router_instance=self, model=deployment)
+                    InitalizeOpenAISDKClient.set_client(
+                        litellm_router_instance=self, model=deployment
+                    )
                     client = self.cache.get_cache(key=cache_key, local_only=True)
                 return client
             else:
@@ -4671,7 +4670,9 @@ def _get_client(self, deployment, kwargs, client_type=None):
                     """
                     Re-initialize the client
                     """
-                    set_client(litellm_router_instance=self, model=deployment)
+                    InitalizeOpenAISDKClient.set_client(
+                        litellm_router_instance=self, model=deployment
+                    )
                     client = self.cache.get_cache(key=cache_key, local_only=True)
                 return client
         else:
@@ -4682,7 +4683,9 @@ def _get_client(self, deployment, kwargs, client_type=None):
                     """
                     Re-initialize the client
                     """
-                    set_client(litellm_router_instance=self, model=deployment)
+                    InitalizeOpenAISDKClient.set_client(
+                        litellm_router_instance=self, model=deployment
+                    )
                     client = self.cache.get_cache(key=cache_key)
                 return client
             else:
@@ -4692,7 +4695,9 @@ def _get_client(self, deployment, kwargs, client_type=None):
                     """
                     Re-initialize the client
                     """
-                    set_client(litellm_router_instance=self, model=deployment)
+                    InitalizeOpenAISDKClient.set_client(
+                        litellm_router_instance=self, model=deployment
+                    )
                     client = self.cache.get_cache(key=cache_key)
                 return client