server: introduce LLM backends

server/reflector/llm/llm_openai.py

@@ -0,0 +1,44 @@
+from reflector.llm.base import LLM
+from reflector.logger import logger
+from reflector.settings import settings
+import json
+import httpx
+
+
+class OpenAILLM(LLM):
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+        self.openai_key = settings.LLM_OPENAI_KEY
+        self.openai_url = settings.LLM_URL
+        self.openai_model = settings.LLM_OPENAI_MODEL
+        self.openai_temperature = settings.LLM_OPENAI_TEMPERATURE
+        self.timeout = settings.LLM_TIMEOUT
+        self.max_tokens = settings.LLM_MAX_TOKENS
+        logger.info(f"LLM use openai backend at {self.openai_url}")
+
+    async def _generate(self, prompt: str, **kwargs) -> str:
+        headers = {
+            "Content-Type": "application/json",
+            "Authorization": f"Bearer {self.openai_key}",
+        }
+
+        logger.debug(f"LLM openai prompt: {prompt}")
+
+        async with httpx.AsyncClient(timeout=self.timeout) as client:
+            response = await client.post(
+                self.openai_url,
+                headers=headers,
+                json={
+                    "model": self.openai_model,
+                    "prompt": prompt,
+                    "max_tokens": self.max_tokens,
+                    "temperature": self.openai_temperature,
+                },
+            )
+            response.raise_for_status()
+            result = response.json()
+            logger.info(f"LLM openai result: {result}")
+            return result["choices"][0]["text"]
+
+
+LLM.register("openai", OpenAILLM)