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			560 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			560 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| import logging
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| from collections.abc import Callable, Generator, Iterable, Sequence
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| from typing import IO, Any, Optional, Union, cast
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| 
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| from configs import dify_config
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| from core.entities.embedding_type import EmbeddingInputType
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| from core.entities.provider_configuration import ProviderConfiguration, ProviderModelBundle
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| from core.entities.provider_entities import ModelLoadBalancingConfiguration
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| from core.errors.error import ProviderTokenNotInitError
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| from core.model_runtime.callbacks.base_callback import Callback
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| from core.model_runtime.entities.llm_entities import LLMResult
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| from core.model_runtime.entities.message_entities import PromptMessage, PromptMessageTool
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| from core.model_runtime.entities.model_entities import ModelType
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| from core.model_runtime.entities.rerank_entities import RerankResult
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| from core.model_runtime.entities.text_embedding_entities import TextEmbeddingResult
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| from core.model_runtime.errors.invoke import InvokeAuthorizationError, InvokeConnectionError, InvokeRateLimitError
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| from core.model_runtime.model_providers.__base.large_language_model import LargeLanguageModel
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| from core.model_runtime.model_providers.__base.moderation_model import ModerationModel
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| from core.model_runtime.model_providers.__base.rerank_model import RerankModel
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| from core.model_runtime.model_providers.__base.speech2text_model import Speech2TextModel
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| from core.model_runtime.model_providers.__base.text_embedding_model import TextEmbeddingModel
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| from core.model_runtime.model_providers.__base.tts_model import TTSModel
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| from core.provider_manager import ProviderManager
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| from extensions.ext_redis import redis_client
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| from models.provider import ProviderType
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| 
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| logger = logging.getLogger(__name__)
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| 
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| 
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| class ModelInstance:
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|     """
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|     Model instance class
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|     """
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| 
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|     def __init__(self, provider_model_bundle: ProviderModelBundle, model: str) -> None:
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|         self.provider_model_bundle = provider_model_bundle
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|         self.model = model
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|         self.provider = provider_model_bundle.configuration.provider.provider
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|         self.credentials = self._fetch_credentials_from_bundle(provider_model_bundle, model)
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|         self.model_type_instance = self.provider_model_bundle.model_type_instance
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|         self.load_balancing_manager = self._get_load_balancing_manager(
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|             configuration=provider_model_bundle.configuration,
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|             model_type=provider_model_bundle.model_type_instance.model_type,
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|             model=model,
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|             credentials=self.credentials,
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|         )
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| 
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|     @staticmethod
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|     def _fetch_credentials_from_bundle(provider_model_bundle: ProviderModelBundle, model: str) -> dict:
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|         """
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|         Fetch credentials from provider model bundle
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|         :param provider_model_bundle: provider model bundle
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|         :param model: model name
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|         :return:
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|         """
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|         configuration = provider_model_bundle.configuration
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|         model_type = provider_model_bundle.model_type_instance.model_type
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|         credentials = configuration.get_current_credentials(model_type=model_type, model=model)
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| 
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|         if credentials is None:
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|             raise ProviderTokenNotInitError(f"Model {model} credentials is not initialized.")
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| 
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|         return credentials
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| 
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|     @staticmethod
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|     def _get_load_balancing_manager(
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|         configuration: ProviderConfiguration, model_type: ModelType, model: str, credentials: dict
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|     ) -> Optional["LBModelManager"]:
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|         """
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|         Get load balancing model credentials
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|         :param configuration: provider configuration
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|         :param model_type: model type
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|         :param model: model name
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|         :param credentials: model credentials
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|         :return:
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|         """
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|         if configuration.model_settings and configuration.using_provider_type == ProviderType.CUSTOM:
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|             current_model_setting = None
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|             # check if model is disabled by admin
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|             for model_setting in configuration.model_settings:
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|                 if model_setting.model_type == model_type and model_setting.model == model:
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|                     current_model_setting = model_setting
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|                     break
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| 
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|             # check if load balancing is enabled
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|             if current_model_setting and current_model_setting.load_balancing_configs:
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|                 # use load balancing proxy to choose credentials
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|                 lb_model_manager = LBModelManager(
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|                     tenant_id=configuration.tenant_id,
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|                     provider=configuration.provider.provider,
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|                     model_type=model_type,
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|                     model=model,
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|                     load_balancing_configs=current_model_setting.load_balancing_configs,
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|                     managed_credentials=credentials if configuration.custom_configuration.provider else None,
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|                 )
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| 
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|                 return lb_model_manager
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| 
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|         return None
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| 
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|     def invoke_llm(
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|         self,
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|         prompt_messages: Sequence[PromptMessage],
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|         model_parameters: Optional[dict] = None,
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|         tools: Sequence[PromptMessageTool] | None = None,
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|         stop: Optional[Sequence[str]] = None,
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|         stream: bool = True,
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|         user: Optional[str] = None,
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|         callbacks: Optional[list[Callback]] = None,
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|     ) -> Union[LLMResult, Generator]:
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|         """
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|         Invoke large language model
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| 
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|         :param prompt_messages: prompt messages
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|         :param model_parameters: model parameters
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|         :param tools: tools for tool calling
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|         :param stop: stop words
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|         :param stream: is stream response
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|         :param user: unique user id
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|         :param callbacks: callbacks
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|         :return: full response or stream response chunk generator result
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|         """
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|         if not isinstance(self.model_type_instance, LargeLanguageModel):
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|             raise Exception("Model type instance is not LargeLanguageModel")
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| 
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|         self.model_type_instance = cast(LargeLanguageModel, self.model_type_instance)
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|         return cast(
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|             Union[LLMResult, Generator],
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|             self._round_robin_invoke(
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|                 function=self.model_type_instance.invoke,
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|                 model=self.model,
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|                 credentials=self.credentials,
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|                 prompt_messages=prompt_messages,
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|                 model_parameters=model_parameters,
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|                 tools=tools,
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|                 stop=stop,
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|                 stream=stream,
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|                 user=user,
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|                 callbacks=callbacks,
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|             ),
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|         )
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| 
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|     def get_llm_num_tokens(
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|         self, prompt_messages: list[PromptMessage], tools: Optional[list[PromptMessageTool]] = None
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|     ) -> int:
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|         """
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|         Get number of tokens for llm
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| 
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|         :param prompt_messages: prompt messages
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|         :param tools: tools for tool calling
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|         :return:
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|         """
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|         if not isinstance(self.model_type_instance, LargeLanguageModel):
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|             raise Exception("Model type instance is not LargeLanguageModel")
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| 
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|         self.model_type_instance = cast(LargeLanguageModel, self.model_type_instance)
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|         return cast(
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|             int,
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|             self._round_robin_invoke(
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|                 function=self.model_type_instance.get_num_tokens,
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|                 model=self.model,
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|                 credentials=self.credentials,
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|                 prompt_messages=prompt_messages,
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|                 tools=tools,
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|             ),
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|         )
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| 
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|     def invoke_text_embedding(
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|         self, texts: list[str], user: Optional[str] = None, input_type: EmbeddingInputType = EmbeddingInputType.DOCUMENT
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|     ) -> TextEmbeddingResult:
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|         """
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|         Invoke large language model
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| 
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|         :param texts: texts to embed
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|         :param user: unique user id
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|         :param input_type: input type
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|         :return: embeddings result
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|         """
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|         if not isinstance(self.model_type_instance, TextEmbeddingModel):
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|             raise Exception("Model type instance is not TextEmbeddingModel")
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| 
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|         self.model_type_instance = cast(TextEmbeddingModel, self.model_type_instance)
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|         return cast(
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|             TextEmbeddingResult,
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|             self._round_robin_invoke(
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|                 function=self.model_type_instance.invoke,
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|                 model=self.model,
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|                 credentials=self.credentials,
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|                 texts=texts,
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|                 user=user,
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|                 input_type=input_type,
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|             ),
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|         )
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| 
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|     def get_text_embedding_num_tokens(self, texts: list[str]) -> int:
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|         """
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|         Get number of tokens for text embedding
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| 
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|         :param texts: texts to embed
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|         :return:
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|         """
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|         if not isinstance(self.model_type_instance, TextEmbeddingModel):
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|             raise Exception("Model type instance is not TextEmbeddingModel")
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| 
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|         self.model_type_instance = cast(TextEmbeddingModel, self.model_type_instance)
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|         return cast(
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|             int,
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|             self._round_robin_invoke(
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|                 function=self.model_type_instance.get_num_tokens,
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|                 model=self.model,
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|                 credentials=self.credentials,
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|                 texts=texts,
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|             ),
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|         )
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| 
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|     def invoke_rerank(
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|         self,
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|         query: str,
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|         docs: list[str],
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|         score_threshold: Optional[float] = None,
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|         top_n: Optional[int] = None,
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|         user: Optional[str] = None,
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|     ) -> RerankResult:
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|         """
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|         Invoke rerank model
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| 
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|         :param query: search query
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|         :param docs: docs for reranking
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|         :param score_threshold: score threshold
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|         :param top_n: top n
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|         :param user: unique user id
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|         :return: rerank result
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|         """
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|         if not isinstance(self.model_type_instance, RerankModel):
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|             raise Exception("Model type instance is not RerankModel")
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| 
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|         self.model_type_instance = cast(RerankModel, self.model_type_instance)
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|         return cast(
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|             RerankResult,
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|             self._round_robin_invoke(
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|                 function=self.model_type_instance.invoke,
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|                 model=self.model,
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|                 credentials=self.credentials,
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|                 query=query,
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|                 docs=docs,
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|                 score_threshold=score_threshold,
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|                 top_n=top_n,
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|                 user=user,
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|             ),
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|         )
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| 
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|     def invoke_moderation(self, text: str, user: Optional[str] = None) -> bool:
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|         """
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|         Invoke moderation model
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| 
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|         :param text: text to moderate
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|         :param user: unique user id
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|         :return: false if text is safe, true otherwise
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|         """
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|         if not isinstance(self.model_type_instance, ModerationModel):
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|             raise Exception("Model type instance is not ModerationModel")
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| 
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|         self.model_type_instance = cast(ModerationModel, self.model_type_instance)
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|         return cast(
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|             bool,
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|             self._round_robin_invoke(
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|                 function=self.model_type_instance.invoke,
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|                 model=self.model,
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|                 credentials=self.credentials,
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|                 text=text,
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|                 user=user,
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|             ),
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|         )
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| 
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|     def invoke_speech2text(self, file: IO[bytes], user: Optional[str] = None) -> str:
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|         """
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|         Invoke large language model
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| 
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|         :param file: audio file
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|         :param user: unique user id
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|         :return: text for given audio file
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|         """
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|         if not isinstance(self.model_type_instance, Speech2TextModel):
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|             raise Exception("Model type instance is not Speech2TextModel")
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| 
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|         self.model_type_instance = cast(Speech2TextModel, self.model_type_instance)
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|         return cast(
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|             str,
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|             self._round_robin_invoke(
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|                 function=self.model_type_instance.invoke,
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|                 model=self.model,
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|                 credentials=self.credentials,
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|                 file=file,
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|                 user=user,
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|             ),
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|         )
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| 
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|     def invoke_tts(self, content_text: str, tenant_id: str, voice: str, user: Optional[str] = None) -> Iterable[bytes]:
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|         """
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|         Invoke large language tts model
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| 
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|         :param content_text: text content to be translated
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|         :param tenant_id: user tenant id
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|         :param voice: model timbre
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|         :param user: unique user id
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|         :return: text for given audio file
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|         """
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|         if not isinstance(self.model_type_instance, TTSModel):
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|             raise Exception("Model type instance is not TTSModel")
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| 
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|         self.model_type_instance = cast(TTSModel, self.model_type_instance)
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|         return cast(
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|             Iterable[bytes],
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|             self._round_robin_invoke(
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|                 function=self.model_type_instance.invoke,
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|                 model=self.model,
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|                 credentials=self.credentials,
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|                 content_text=content_text,
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|                 user=user,
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|                 tenant_id=tenant_id,
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|                 voice=voice,
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|             ),
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|         )
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| 
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|     def _round_robin_invoke(self, function: Callable[..., Any], *args, **kwargs) -> Any:
 | |
|         """
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|         Round-robin invoke
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|         :param function: function to invoke
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|         :param args: function args
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|         :param kwargs: function kwargs
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|         :return:
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|         """
 | |
|         if not self.load_balancing_manager:
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|             return function(*args, **kwargs)
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| 
 | |
|         last_exception: Union[InvokeRateLimitError, InvokeAuthorizationError, InvokeConnectionError, None] = None
 | |
|         while True:
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|             lb_config = self.load_balancing_manager.fetch_next()
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|             if not lb_config:
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|                 if not last_exception:
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|                     raise ProviderTokenNotInitError("Model credentials is not initialized.")
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|                 else:
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|                     raise last_exception
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| 
 | |
|             try:
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|                 if "credentials" in kwargs:
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|                     del kwargs["credentials"]
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|                 return function(*args, **kwargs, credentials=lb_config.credentials)
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|             except InvokeRateLimitError as e:
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|                 # expire in 60 seconds
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|                 self.load_balancing_manager.cooldown(lb_config, expire=60)
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|                 last_exception = e
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|                 continue
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|             except (InvokeAuthorizationError, InvokeConnectionError) as e:
 | |
|                 # expire in 10 seconds
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|                 self.load_balancing_manager.cooldown(lb_config, expire=10)
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|                 last_exception = e
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|                 continue
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|             except Exception as e:
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|                 raise e
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| 
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|     def get_tts_voices(self, language: Optional[str] = None) -> list:
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|         """
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|         Invoke large language tts model voices
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| 
 | |
|         :param language: tts language
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|         :return: tts model voices
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|         """
 | |
|         if not isinstance(self.model_type_instance, TTSModel):
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|             raise Exception("Model type instance is not TTSModel")
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| 
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|         self.model_type_instance = cast(TTSModel, self.model_type_instance)
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|         return self.model_type_instance.get_tts_model_voices(
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|             model=self.model, credentials=self.credentials, language=language
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|         )
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| 
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| 
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| class ModelManager:
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|     def __init__(self) -> None:
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|         self._provider_manager = ProviderManager()
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| 
 | |
|     def get_model_instance(self, tenant_id: str, provider: str, model_type: ModelType, model: str) -> ModelInstance:
 | |
|         """
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|         Get model instance
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|         :param tenant_id: tenant id
 | |
|         :param provider: provider name
 | |
|         :param model_type: model type
 | |
|         :param model: model name
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|         :return:
 | |
|         """
 | |
|         if not provider:
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|             return self.get_default_model_instance(tenant_id, model_type)
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| 
 | |
|         provider_model_bundle = self._provider_manager.get_provider_model_bundle(
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|             tenant_id=tenant_id, provider=provider, model_type=model_type
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|         )
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| 
 | |
|         return ModelInstance(provider_model_bundle, model)
 | |
| 
 | |
|     def get_default_provider_model_name(self, tenant_id: str, model_type: ModelType) -> tuple[str, str]:
 | |
|         """
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|         Return first provider and the first model in the provider
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|         :param tenant_id: tenant id
 | |
|         :param model_type: model type
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|         :return: provider name, model name
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|         """
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|         return self._provider_manager.get_first_provider_first_model(tenant_id, model_type)
 | |
| 
 | |
|     def get_default_model_instance(self, tenant_id: str, model_type: ModelType) -> ModelInstance:
 | |
|         """
 | |
|         Get default model instance
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|         :param tenant_id: tenant id
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|         :param model_type: model type
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|         :return:
 | |
|         """
 | |
|         default_model_entity = self._provider_manager.get_default_model(tenant_id=tenant_id, model_type=model_type)
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| 
 | |
|         if not default_model_entity:
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|             raise ProviderTokenNotInitError(f"Default model not found for {model_type}")
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| 
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|         return self.get_model_instance(
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|             tenant_id=tenant_id,
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|             provider=default_model_entity.provider.provider,
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|             model_type=model_type,
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|             model=default_model_entity.model,
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|         )
 | |
| 
 | |
| 
 | |
| class LBModelManager:
 | |
|     def __init__(
 | |
|         self,
 | |
|         tenant_id: str,
 | |
|         provider: str,
 | |
|         model_type: ModelType,
 | |
|         model: str,
 | |
|         load_balancing_configs: list[ModelLoadBalancingConfiguration],
 | |
|         managed_credentials: Optional[dict] = None,
 | |
|     ) -> None:
 | |
|         """
 | |
|         Load balancing model manager
 | |
|         :param tenant_id: tenant_id
 | |
|         :param provider: provider
 | |
|         :param model_type: model_type
 | |
|         :param model: model name
 | |
|         :param load_balancing_configs: all load balancing configurations
 | |
|         :param managed_credentials: credentials if load balancing configuration name is __inherit__
 | |
|         """
 | |
|         self._tenant_id = tenant_id
 | |
|         self._provider = provider
 | |
|         self._model_type = model_type
 | |
|         self._model = model
 | |
|         self._load_balancing_configs = load_balancing_configs
 | |
| 
 | |
|         for load_balancing_config in self._load_balancing_configs[:]:  # Iterate over a shallow copy of the list
 | |
|             if load_balancing_config.name == "__inherit__":
 | |
|                 if not managed_credentials:
 | |
|                     # remove __inherit__ if managed credentials is not provided
 | |
|                     self._load_balancing_configs.remove(load_balancing_config)
 | |
|                 else:
 | |
|                     load_balancing_config.credentials = managed_credentials
 | |
| 
 | |
|     def fetch_next(self) -> Optional[ModelLoadBalancingConfiguration]:
 | |
|         """
 | |
|         Get next model load balancing config
 | |
|         Strategy: Round Robin
 | |
|         :return:
 | |
|         """
 | |
|         cache_key = "model_lb_index:{}:{}:{}:{}".format(
 | |
|             self._tenant_id, self._provider, self._model_type.value, self._model
 | |
|         )
 | |
| 
 | |
|         cooldown_load_balancing_configs = []
 | |
|         max_index = len(self._load_balancing_configs)
 | |
| 
 | |
|         while True:
 | |
|             current_index = redis_client.incr(cache_key)
 | |
|             current_index = cast(int, current_index)
 | |
|             if current_index >= 10000000:
 | |
|                 current_index = 1
 | |
|                 redis_client.set(cache_key, current_index)
 | |
| 
 | |
|             redis_client.expire(cache_key, 3600)
 | |
|             if current_index > max_index:
 | |
|                 current_index = current_index % max_index
 | |
| 
 | |
|             real_index = current_index - 1
 | |
|             if real_index > max_index:
 | |
|                 real_index = 0
 | |
| 
 | |
|             config: ModelLoadBalancingConfiguration = self._load_balancing_configs[real_index]
 | |
| 
 | |
|             if self.in_cooldown(config):
 | |
|                 cooldown_load_balancing_configs.append(config)
 | |
|                 if len(cooldown_load_balancing_configs) >= len(self._load_balancing_configs):
 | |
|                     # all configs are in cooldown
 | |
|                     return None
 | |
| 
 | |
|                 continue
 | |
| 
 | |
|             if dify_config.DEBUG:
 | |
|                 logger.info(
 | |
|                     f"Model LB\nid: {config.id}\nname:{config.name}\n"
 | |
|                     f"tenant_id: {self._tenant_id}\nprovider: {self._provider}\n"
 | |
|                     f"model_type: {self._model_type.value}\nmodel: {self._model}"
 | |
|                 )
 | |
| 
 | |
|             return config
 | |
| 
 | |
|         return None
 | |
| 
 | |
|     def cooldown(self, config: ModelLoadBalancingConfiguration, expire: int = 60) -> None:
 | |
|         """
 | |
|         Cooldown model load balancing config
 | |
|         :param config: model load balancing config
 | |
|         :param expire: cooldown time
 | |
|         :return:
 | |
|         """
 | |
|         cooldown_cache_key = "model_lb_index:cooldown:{}:{}:{}:{}:{}".format(
 | |
|             self._tenant_id, self._provider, self._model_type.value, self._model, config.id
 | |
|         )
 | |
| 
 | |
|         redis_client.setex(cooldown_cache_key, expire, "true")
 | |
| 
 | |
|     def in_cooldown(self, config: ModelLoadBalancingConfiguration) -> bool:
 | |
|         """
 | |
|         Check if model load balancing config is in cooldown
 | |
|         :param config: model load balancing config
 | |
|         :return:
 | |
|         """
 | |
|         cooldown_cache_key = "model_lb_index:cooldown:{}:{}:{}:{}:{}".format(
 | |
|             self._tenant_id, self._provider, self._model_type.value, self._model, config.id
 | |
|         )
 | |
| 
 | |
|         res: bool = redis_client.exists(cooldown_cache_key)
 | |
|         return res
 | |
| 
 | |
|     @staticmethod
 | |
|     def get_config_in_cooldown_and_ttl(
 | |
|         tenant_id: str, provider: str, model_type: ModelType, model: str, config_id: str
 | |
|     ) -> tuple[bool, int]:
 | |
|         """
 | |
|         Get model load balancing config is in cooldown and ttl
 | |
|         :param tenant_id: workspace id
 | |
|         :param provider: provider name
 | |
|         :param model_type: model type
 | |
|         :param model: model name
 | |
|         :param config_id: model load balancing config id
 | |
|         :return:
 | |
|         """
 | |
|         cooldown_cache_key = "model_lb_index:cooldown:{}:{}:{}:{}:{}".format(
 | |
|             tenant_id, provider, model_type.value, model, config_id
 | |
|         )
 | |
| 
 | |
|         ttl = redis_client.ttl(cooldown_cache_key)
 | |
|         if ttl == -2:
 | |
|             return False, 0
 | |
| 
 | |
|         ttl = cast(int, ttl)
 | |
|         return True, ttl
 | 
