app/settings.py

import os
from typing import Dict
from llama_index.core.settings import Settings


def init_settings():
    model_provider = os.getenv("MODEL_PROVIDER")
    if model_provider == "openai":
        init_openai()
    elif model_provider == "ollama":
        init_ollama()
    elif model_provider == "anthropic":
        init_anthropic()
    elif model_provider == "gemini":
        init_gemini()
    else:
        raise ValueError(f"Invalid model provider: {model_provider}")
    Settings.chunk_size = int(os.getenv("CHUNK_SIZE", "1024"))
    Settings.chunk_overlap = int(os.getenv("CHUNK_OVERLAP", "20"))


def init_ollama():
    from llama_index.llms.ollama import Ollama
    from llama_index.embeddings.ollama import OllamaEmbedding

    base_url = os.getenv("OLLAMA_BASE_URL") or "http://127.0.0.1:11434"
    Settings.embed_model = OllamaEmbedding(
        base_url=base_url,
        model_name=os.getenv("EMBEDDING_MODEL"),
    )
    Settings.llm = Ollama(base_url=base_url, model=os.getenv("MODEL"))


def init_openai():
    from llama_index.llms.openai import OpenAI
    from llama_index.embeddings.openai import OpenAIEmbedding
    from llama_index.core.constants import DEFAULT_TEMPERATURE

    max_tokens = os.getenv("LLM_MAX_TOKENS")
    config = {
        "model": os.getenv("MODEL"),
        "temperature": float(os.getenv("LLM_TEMPERATURE", DEFAULT_TEMPERATURE)),
        "max_tokens": int(max_tokens) if max_tokens is not None else None,
    }
    Settings.llm = OpenAI(**config)

    dimensions = os.getenv("EMBEDDING_DIM")
    config = {
        "model": os.getenv("EMBEDDING_MODEL"),
        "dimensions": int(dimensions) if dimensions is not None else None,
    }
    Settings.embed_model = OpenAIEmbedding(**config)


def init_anthropic():
    from llama_index.llms.anthropic import Anthropic
    from llama_index.embeddings.huggingface import HuggingFaceEmbedding

    model_map: Dict[str, str] = {
        "claude-3-opus": "claude-3-opus-20240229",
        "claude-3-sonnet": "claude-3-sonnet-20240229",
        "claude-3-haiku": "claude-3-haiku-20240307",
        "claude-2.1": "claude-2.1",
        "claude-instant-1.2": "claude-instant-1.2",
    }

    embed_model_map: Dict[str, str] = {
        "all-MiniLM-L6-v2": "sentence-transformers/all-MiniLM-L6-v2",
        "all-mpnet-base-v2": "sentence-transformers/all-mpnet-base-v2",
    }

    Settings.llm = Anthropic(model=model_map[os.getenv("MODEL")])
    Settings.embed_model = HuggingFaceEmbedding(
        model_name=embed_model_map[os.getenv("EMBEDDING_MODEL")]
    )


def init_gemini():
    from llama_index.llms.gemini import Gemini
    from llama_index.embeddings.gemini import GeminiEmbedding

    model_map: Dict[str, str] = {
        "gemini-1.5-pro-latest": "models/gemini-1.5-pro-latest",
        "gemini-pro": "models/gemini-pro",
        "gemini-pro-vision": "models/gemini-pro-vision",
    }

    embed_model_map: Dict[str, str] = {
        "embedding-001": "models/embedding-001",
        "text-embedding-004": "models/text-embedding-004",
    }

    Settings.llm = Gemini(model=model_map[os.getenv("MODEL")])
    Settings.embed_model = GeminiEmbedding(
        model_name=embed_model_map[os.getenv("EMBEDDING_MODEL")]
    )