Initial commit: InternalAuditInterprise

backend/app/llm/providers.py

@@ -0,0 +1,80 @@
+"""具体 LLM Provider 实现：DashScope（公网千问，仅 dev）、vLLM（本地，prod）。
+
+两者均走 OpenAI 兼容的 /chat/completions 协议。
+"""
+
+from __future__ import annotations
+
+import httpx
+
+from app.llm.base import ChatMessage, LLMProvider, LLMResponse
+
+
+class DashScopeProvider(LLMProvider):
+    """公网千问（DashScope，OpenAI 兼容模式）。仅限开发测试，且只允许脱敏/样例假数据。"""
+
+    name = "dashscope"
+    egress = True  # 走公网，出域
+
+    _BASE_URL = "https://dashscope.aliyuncs.com/compatible-mode/v1"
+
+    def __init__(self, api_key: str, model: str, timeout: float = 30.0) -> None:
+        self._api_key = api_key
+        self._model = model
+        self._timeout = timeout
+
+    def chat(self, messages: list[ChatMessage], **kwargs) -> LLMResponse:
+        payload = {
+            "model": self._model,
+            "messages": [{"role": m.role, "content": m.content} for m in messages],
+            **kwargs,
+        }
+        headers = {"Authorization": f"Bearer {self._api_key}"}
+        with httpx.Client(timeout=self._timeout) as client:
+            resp = client.post(
+                f"{self._BASE_URL}/chat/completions", json=payload, headers=headers
+            )
+            resp.raise_for_status()
+            data = resp.json()
+        content = data["choices"][0]["message"]["content"]
+        return LLMResponse(
+            content=content, model=self._model, provider=self.name, egress=True, raw=data
+        )
+
+    def health(self) -> bool:
+        return bool(self._api_key)
+
+
+class VllmProvider(LLMProvider):
+    """本地 vLLM（OpenAI 兼容）。生产使用，数据不出域。"""
+
+    name = "vllm"
+    egress = False
+
+    def __init__(self, base_url: str, model: str, timeout: float = 60.0) -> None:
+        self._base_url = base_url.rstrip("/")
+        self._model = model
+        self._timeout = timeout
+
+    def chat(self, messages: list[ChatMessage], **kwargs) -> LLMResponse:
+        payload = {
+            "model": self._model,
+            "messages": [{"role": m.role, "content": m.content} for m in messages],
+            **kwargs,
+        }
+        with httpx.Client(timeout=self._timeout) as client:
+            resp = client.post(f"{self._base_url}/chat/completions", json=payload)
+            resp.raise_for_status()
+            data = resp.json()
+        content = data["choices"][0]["message"]["content"]
+        return LLMResponse(
+            content=content, model=self._model, provider=self.name, egress=False, raw=data
+        )
+
+    def health(self) -> bool:
+        try:
+            with httpx.Client(timeout=5.0) as client:
+                resp = client.get(f"{self._base_url}/models")
+                return resp.status_code == 200
+        except httpx.HTTPError:
+            return False