agent-platform/services/model-gateway-service/app/application/services.py

from core_domain import ChatCompletionRequestContract, ChatCompletionResponseContract

from app.bootstrap.settings import ModelGatewayServiceSettings
from app.infrastructure.provider import ModelProviderClient


class ModelGatewayApplicationService:
    def __init__(
        self,
        *,
        provider_client: ModelProviderClient,
        settings: ModelGatewayServiceSettings,
    ) -> None:
        self.provider_client = provider_client
        self.settings = settings

    def create_chat_completion(
        self,
        payload: ChatCompletionRequestContract,
    ) -> ChatCompletionResponseContract:
        resolved_payload = payload.model_copy(
            update={
                "model": payload.model or self.settings.default_model,
            }
        )
        return self.provider_client.create_chat_completion(resolved_payload)