File size: 8,076 Bytes
d557d77
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
"""Response generation using local or remote LLMs."""

from typing import Optional

from coderag.config import get_settings
from coderag.generation.citations import CitationParser
from coderag.generation.prompts import SYSTEM_PROMPT, build_prompt, build_no_context_response
from coderag.logging import get_logger
from coderag.models.response import Response
from coderag.models.query import Query
from coderag.retrieval.retriever import Retriever

logger = get_logger(__name__)


class ResponseGenerator:
    """Generates grounded responses using local or remote LLMs."""

    def __init__(
        self,
        retriever: Optional[Retriever] = None,
    ) -> None:
        self.settings = get_settings()
        self.retriever = retriever or Retriever()
        self.citation_parser = CitationParser()

        self.provider = self.settings.models.llm_provider.lower()
        self._client = None
        self._local_model = None
        self._local_tokenizer = None

        logger.info("ResponseGenerator initialized", provider=self.provider)

    def _get_api_client(self):
        """Get or create API client for remote providers."""
        if self._client is not None:
            return self._client

        import httpx
        from openai import OpenAI

        api_key = self.settings.models.llm_api_key
        if not api_key:
            raise ValueError(f"API key required for provider: {self.provider}")

        # Provider-specific configurations
        provider_configs = {
            "openai": {
                "base_url": "https://api.openai.com/v1",
                "default_model": "gpt-4o-mini",
            },
            "groq": {
                "base_url": "https://api.groq.com/openai/v1",
                "default_model": "llama-3.3-70b-versatile",
            },
            "anthropic": {
                "base_url": "https://api.anthropic.com/v1",
                "default_model": "claude-3-5-sonnet-20241022",
            },
            "openrouter": {
                "base_url": "https://openrouter.ai/api/v1",
                "default_model": "anthropic/claude-3.5-sonnet",
            },
            "together": {
                "base_url": "https://api.together.xyz/v1",
                "default_model": "meta-llama/Llama-3.3-70B-Instruct-Turbo",
            },
        }

        config = provider_configs.get(self.provider, {})
        base_url = self.settings.models.llm_api_base or config.get("base_url")

        if not base_url:
            raise ValueError(f"Unknown provider: {self.provider}")

        # Set default model if not specified and it's a known provider
        if self.settings.models.llm_name.startswith("Qwen/"):
            self.model_name = config.get("default_model", self.settings.models.llm_name)
        else:
            self.model_name = self.settings.models.llm_name

        self._client = OpenAI(
            api_key=api_key,
            base_url=base_url,
            http_client=httpx.Client(timeout=120.0),
        )

        logger.info("API client created", provider=self.provider, model=self.model_name)
        return self._client

    def _load_local_model(self):
        """Load local model with transformers."""
        if self._local_model is not None:
            return

        import torch
        from transformers import AutoModelForCausalLM, AutoTokenizer, BitsAndBytesConfig

        if not torch.cuda.is_available():
            raise RuntimeError(
                "Local LLM requires a CUDA-capable GPU. Options:\n"
                "  1. Use a cloud provider (free): MODEL_LLM_PROVIDER=groq\n"
                "     Get API key at: https://console.groq.com/keys\n"
                "  2. Install CUDA and a compatible GPU"
            )

        logger.info("Loading local LLM", model=self.settings.models.llm_name)

        if self.settings.models.llm_use_4bit:
            bnb_config = BitsAndBytesConfig(
                load_in_4bit=True,
                bnb_4bit_quant_type="nf4",
                bnb_4bit_compute_dtype=torch.float16,
                bnb_4bit_use_double_quant=True,
            )
        else:
            bnb_config = None

        self._local_tokenizer = AutoTokenizer.from_pretrained(
            self.settings.models.llm_name,
            trust_remote_code=True,
        )

        self._local_model = AutoModelForCausalLM.from_pretrained(
            self.settings.models.llm_name,
            quantization_config=bnb_config,
            device_map=self.settings.models.llm_device_map,
            trust_remote_code=True,
            torch_dtype=torch.float16,
        )

        logger.info("Local LLM loaded successfully")

    def generate(self, query: Query) -> Response:
        """Generate a response for a query."""
        # Retrieve relevant chunks
        chunks, context = self.retriever.retrieve_with_context(
            query.question,
            query.repo_id,
            query.top_k,
        )

        # Handle no results
        if not chunks:
            return Response(
                answer=build_no_context_response(),
                citations=[],
                retrieved_chunks=[],
                grounded=False,
                query_id=query.id,
            )

        # Build prompt and generate
        prompt = build_prompt(query.question, context)

        if self.provider == "local":
            answer = self._generate_local(prompt)
        else:
            answer = self._generate_api(prompt)

        # Parse citations from answer
        citations = self.citation_parser.parse_citations(answer)

        # Determine if response is grounded
        grounded = len(citations) > 0 and len(chunks) > 0

        return Response(
            answer=answer,
            citations=citations,
            retrieved_chunks=chunks,
            grounded=grounded,
            query_id=query.id,
        )

    def _generate_api(self, prompt: str) -> str:
        """Generate using remote API."""
        client = self._get_api_client()

        messages = [
            {"role": "system", "content": SYSTEM_PROMPT},
            {"role": "user", "content": prompt},
        ]

        response = client.chat.completions.create(
            model=self.model_name,
            messages=messages,
            max_tokens=self.settings.models.llm_max_new_tokens,
            temperature=self.settings.models.llm_temperature,
            top_p=self.settings.models.llm_top_p,
        )

        return response.choices[0].message.content.strip()

    def _generate_local(self, prompt: str) -> str:
        """Generate using local model."""
        import torch

        self._load_local_model()

        messages = [
            {"role": "system", "content": SYSTEM_PROMPT},
            {"role": "user", "content": prompt},
        ]

        text = self._local_tokenizer.apply_chat_template(
            messages,
            tokenize=False,
            add_generation_prompt=True,
        )

        inputs = self._local_tokenizer(text, return_tensors="pt").to(self._local_model.device)

        with torch.no_grad():
            outputs = self._local_model.generate(
                **inputs,
                max_new_tokens=self.settings.models.llm_max_new_tokens,
                temperature=self.settings.models.llm_temperature,
                top_p=self.settings.models.llm_top_p,
                do_sample=True,
                pad_token_id=self._local_tokenizer.eos_token_id,
            )

        generated = outputs[0][inputs["input_ids"].shape[1]:]
        response = self._local_tokenizer.decode(generated, skip_special_tokens=True)

        return response.strip()

    def unload(self) -> None:
        """Unload models from memory."""
        if self._local_model is not None:
            del self._local_model
            self._local_model = None
        if self._local_tokenizer is not None:
            del self._local_tokenizer
            self._local_tokenizer = None

        import torch
        if torch.cuda.is_available():
            torch.cuda.empty_cache()

        logger.info("Models unloaded")