63 lines
2.2 KiB
Python
63 lines
2.2 KiB
Python
"""Lightweight local LLM wrappers.
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This file provides simple wrappers for `llama_cpp` and `transformers` backends.
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They are intentionally minimal — adapt to your runtime and model formats.
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"""
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from typing import Optional
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import logging
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logger = logging.getLogger(__name__)
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class BaseLLM:
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def generate(self, prompt: str) -> str:
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raise NotImplementedError()
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class LlamaCPPWrapper(BaseLLM):
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def __init__(self, model_path: str):
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try:
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from llama_cpp import Llama
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self._llm = Llama(model_path=model_path)
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except Exception:
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logger.exception("llama_cpp is unavailable or model failed to load")
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self._llm = None
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def generate(self, prompt: str) -> str:
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if self._llm is None:
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raise RuntimeError("Llama model not available")
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resp = self._llm(prompt)
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return resp.get("text") if isinstance(resp, dict) else str(resp)
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class TransformersWrapper(BaseLLM):
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def __init__(self, model_name_or_path: str):
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try:
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from transformers import AutoModelForCausalLM, AutoTokenizer
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import torch
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self.tokenizer = AutoTokenizer.from_pretrained(model_name_or_path)
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self.model = AutoModelForCausalLM.from_pretrained(model_name_or_path, torch_dtype=torch.float16, device_map="auto")
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except Exception:
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logger.exception("transformers not available or model failed to load")
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self.model = None
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self.tokenizer = None
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def generate(self, prompt: str) -> str:
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if self.model is None or self.tokenizer is None:
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raise RuntimeError("Transformers model not available")
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inputs = self.tokenizer(prompt, return_tensors="pt")
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outputs = self.model.generate(**inputs, max_new_tokens=256)
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return self.tokenizer.decode(outputs[0], skip_special_tokens=True)
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def get_llm_for_domain(domain: str, prefer: str | None = None) -> BaseLLM:
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# Basic loader: choose Llama (gguf) if file exists, else fall back to transformers
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model_dir = "models" / domain
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gguf = model_dir / "model.gguf"
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if gguf.exists():
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return LlamaCPPWrapper(str(gguf))
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# fallback: try transformers
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return TransformersWrapper(str(model_dir))
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