1

backend/app/rag/llm_client.py

@@ -0,0 +1,151 @@
+import json
+from pathlib import Path
+from typing import Any
+
+import requests
+
+
+class LLMConfigManager:
+    def __init__(self, config_path: str):
+        self.config_path = Path(config_path)
+
+    def load(self) -> dict:
+        if not self.config_path.exists():
+            return {}
+        with self.config_path.open("r", encoding="utf-8-sig") as file:
+            return json.load(file)
+
+
+def _join_url(base_url: str, path: str) -> str:
+    return f"{base_url.rstrip('/')}/{path.lstrip('/')}"
+
+
+def _timeout(config: dict) -> int:
+    section = config.get("request", {}) if isinstance(config, dict) else {}
+    try:
+        return int(section.get("timeout_seconds", 45))
+    except Exception:
+        return 45
+
+
+def _extract_openai_text(payload: Any) -> str:
+    if isinstance(payload, dict):
+        choices = payload.get("choices")
+        if isinstance(choices, list) and choices:
+            msg = choices[0].get("message") if isinstance(choices[0], dict) else {}
+            if isinstance(msg, dict) and msg.get("content"):
+                return str(msg["content"])
+        if payload.get("answer"):
+            return str(payload["answer"])
+        if payload.get("data"):
+            return json.dumps(payload["data"], ensure_ascii=False)
+    return json.dumps(payload, ensure_ascii=False) if isinstance(payload, (dict, list)) else str(payload)
+
+
+def ask_fastgpt(config: dict, prompt: str, context: str = "", custom_uid: str = "") -> dict:
+    section = config.get("fastgpt", {})
+    base_url = section.get("base_url", "").strip()
+    api_key = section.get("api_key", "").strip()
+    chat_id = str(section.get("chat_id", "111"))
+    model = section.get("model", "")
+    timeout = _timeout(config)
+
+    if not base_url or not api_key:
+        return {"ok": False, "message": "FastGPT 未配置 base_url 或 api_key"}
+
+    url = _join_url(base_url, "/v1/chat/completions")
+    headers = {
+        "Authorization": f"Bearer {api_key}",
+        "Content-Type": "application/json",
+    }
+
+    content = prompt if not context else f"请基于以下本地知识库内容回答。\n\n知识库:\n{context}\n\n问题: {prompt}"
+    messages = []
+    system_prompt = section.get("system_prompt")
+    if system_prompt:
+        messages.append({"role": "system", "content": system_prompt})
+    messages.append({"role": "user", "content": content})
+
+    use_custom_uid = custom_uid or section.get("custom_uid", "")
+    payload = {
+        "chatId": chat_id,
+        "stream": False,
+        "detail": False,
+        "messages": messages,
+    }
+    if model:
+        payload["model"] = model
+    if use_custom_uid:
+        payload["customUid"] = use_custom_uid
+
+    try:
+        response = requests.post(url, headers=headers, json=payload, timeout=timeout, allow_redirects=True)
+        if response.status_code >= 400:
+            return {
+                "ok": False,
+                "message": f"FastGPT 调用失败: HTTP {response.status_code}",
+                "detail": response.text,
+            }
+
+        data = response.json()
+        return {
+            "ok": True,
+            "provider": "fastgpt",
+            "raw": data,
+            "answer": _extract_openai_text(data),
+        }
+    except Exception as exc:
+        return {
+            "ok": False,
+            "message": "FastGPT 请求异常",
+            "detail": str(exc),
+        }
+
+
+def ask_dify(config: dict, prompt: str, context: str = "", user: str = "anonymous") -> dict:
+    section = config.get("dify", {})
+    base_url = section.get("base_url", "").strip()
+    api_key = section.get("api_key", "").strip()
+    timeout = _timeout(config)
+
+    if not base_url or not api_key:
+        return {"ok": False, "message": "Dify 未配置 base_url 或 api_key"}
+
+    url = _join_url(base_url, "/v1/chat-messages")
+    headers = {
+        "Authorization": f"Bearer {api_key}",
+        "Content-Type": "application/json",
+    }
+
+    query = prompt if not context else f"知识库上下文:\n{context}\n\n用户问题:\n{prompt}"
+    payload = {
+        "inputs": {},
+        "query": query,
+        "response_mode": "blocking",
+        "conversation_id": "",
+        "user": user,
+    }
+
+    try:
+        response = requests.post(url, headers=headers, json=payload, timeout=timeout, allow_redirects=True)
+        if response.status_code >= 400:
+            return {
+                "ok": False,
+                "message": f"Dify 调用失败: HTTP {response.status_code}",
+                "detail": response.text,
+            }
+
+        data = response.json()
+        answer = data.get("answer") or _extract_openai_text(data)
+        return {
+            "ok": True,
+            "provider": "dify",
+            "raw": data,
+            "answer": answer,
+        }
+    except Exception as exc:
+        return {
+            "ok": False,
+            "message": "Dify 请求异常",
+            "detail": str(exc),
+        }